HomeMy WebLinkAboutTHE STANDARD AT FORT COLLINS - PDP - PDP160035 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTGeotechnical Engineering Report
Standard at Fort Collins
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
September 8, 2016
Terracon Project No. 20165058
Prepared for:
Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Prepared by:
Terracon Consultants, Inc.
Fort Collins, Colorado
TABLE OF CONTENTS
Page
EXECUTIVE SUMMARY ............................................................................................................ i
1.0 INTRODUCTION .............................................................................................................1
2.0 PROJECT INFORMATION .............................................................................................1
2.1 Project Description ...............................................................................................1
2.2 Site Location and Description...............................................................................2
3.0 SUBSURFACE CONDITIONS ........................................................................................3
3.1 Typical Subsurface Profile ...................................................................................3
3.2 Laboratory Testing ...............................................................................................3
3.3 Corrosion Protection (Water-Soluble Sulfates) .....................................................4
3.4 Groundwater ........................................................................................................4
3.5 Seismic Refraction ...............................................................................................5
3.6 Pressuremeter Testing .........................................................................................5
4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ......................................6
4.1 Geotechnical Considerations ...............................................................................6
4.1.1 Existing, Undocumented Fill .....................................................................6
4.1.2 Groundwater .............................................................................................6
4.1.3 Expansive Soils and Bedrock ...................................................................7
4.1.4 Permanent Dewatering .............................................................................7
4.1.5 Foundation and Floor Slab Recommendations .........................................8
4.2 Earthwork.............................................................................................................9
4.2.1 Site Preparation ........................................................................................9
4.2.2 Demolition ................................................................................................9
4.2.3 Excavation ................................................................................................9
4.2.4 Subgrade Preparation .............................................................................10
4.2.5 Fill Materials and Placement ....................................................................11
4.2.6 Compaction Requirements ......................................................................12
4.2.7 Utility Trench Backfill ..............................................................................12
4.2.8 Grading and Drainage .............................................................................13
4.2.9 Exterior Slab Design and Construction ...................................................14
4.3 Foundations .......................................................................................................14
4.3.1 Drilled Piers Bottomed in Bedrock - Design Recommendations ..............14
4.3.2 Drilled Piers Bottomed in Bedrock - Construction Considerations ...........15
4.3.6 Helical Pile Foundations .........................................................................16
4.3.7 Spread Footings - Design Recommendations .........................................17
4.3.8 Spread Footings - Construction Considerations ......................................18
4.4 Seismic Considerations......................................................................................18
4.5 Floor Systems ....................................................................................................18
4.5.1 Floor System - Design Recommendations ..............................................19
4.5.2 Floor Systems - Construction Considerations .........................................19
4.6 Lateral Earth Pressures .....................................................................................20
4.7 Pavements .........................................................................................................21
4.7.1 Pavements – Subgrade Preparation .......................................................21
4.7.2 Pavements – Design Recommendations ................................................21
4.7.3 Pavements – Construction Considerations .............................................24
4.7.4 Pavements – Maintenance .....................................................................24
5.0 GENERAL COMMENTS ...............................................................................................24
TABLE OF CONTENTS (continued)
Appendix A – FIELD EXPLORATION
Exhibit A-1 Site Location Map
Exhibit A-2 Exploration Plan
Exhibits A-3 and A-4 Field Exploration Description
Exhibits A-5 to A-11 Boring Logs
Exhibit A-12 ReMI Profile
Exhibits A-13 to A-17 Pressuremeter Test Results
Appendix B – LABORATORY TESTING
Exhibit B-1 Laboratory Testing Description
Exhibit B-2 Atterberg Limits Test Results
Exhibits B-3 to B-5 Grain-size Distribution Test Results
Exhibits B-6 to B-10 Swell-consolidation Test Results
Exhibit B-11 Unconfined Compression Test Results
Exhibits B-12 to B-13 Corrosivity Test Results
Appendix C – SUPPORTING DOCUMENTS
Exhibit C-1 General Notes
Exhibit C-2 Unified Soil Classification System
Exhibit C-3 Description of Rock Properties
Exhibit C-4 Laboratory Test Significance and Purpose
Exhibits C-5 and C-6 Report Terminology
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
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EXECUTIVE SUMMARY
A geotechnical investigation has been performed for the proposed Standard at Fort Collins project
to be constructed northeast of the intersection of West Prospect Road and Sheely Drive in Fort
Collins, Colorado. Seven (7) borings, presented as Exhibits A-5 through A-11 and designated as
Boring No. 1 through Boring No. 7, were performed to depths of approximately 35 to 63 feet below
existing site grades. This report specifically addresses the recommendations for the proposed
structures. Borings performed in these areas are for informational purposes and will be utilized by
others.
Based on the information obtained from our subsurface exploration, the site can be developed for
the proposed project. However, the following geotechnical considerations were identified and will
need to be considered:
n Existing undocumented fill was encountered to depths up to about 5½ feet in the borings
drilled at the Blue Ridge Apartment site (Boring Nos. 1 through 4). Considering the site
has been developed for many years prior to our study, it is also likely other areas of the site
are underlain by fill materials of varying thickness. The existing fill soils should be removed
and replaced with engineered fill beneath proposed foundations and floor slabs.
n Groundwater was measured at depths ranging from about 14.4 to 22 feet below existing
site grades. Depending on the final design and depth of below-grade areas, groundwater
may impact construction as well as require management throughout the life of the project.
n The proposed parking structure and buildings that will include heavy to moderate
foundation loads may be supported on either drilled piers bottomed in bedrock or helical
piles bottomed in bedrock. Based on the building loads provided, 1 and 2-story structures
will impart comparatively lower foundation loads; thus, we believe a spread footing
foundation system bearing on properly prepared on-site soils or properly placed
engineered fill can be utilized for support of these structures.
n A slab-on-grade floor system is recommended for the proposed buildings, provided that
some movement of the floor system can be tolerated. Floor system performance is directly
related to the subgrade soils. The soils on-site consist of clayey sand fill and native sandy
lean clay, which offer fair to poor subgrade support. To reduce risk for movement and
enhance floor slab performance, we recommend placing at least 12 inches of CDOT Class
1 structure backfill below floor slabs.
n The amount of movement of foundations, floor slabs, pavements, etc. will be related to the
wetting of underlying supporting soils. Therefore, it is imperative the recommendations
discussed in the 4.2.8 Grading and Drainage section of this report be followed to reduce
potential movement.
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September 8, 2016 ■ Terracon Project No. 20165058
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n The 2012 International Building Code, Table 1613.5.2 IBC seismic site classification for this
site is D.
n Close monitoring of the construction operations discussed herein will be critical in achieving
the design subgrade support. We therefore recommend that Terracon be retained to
monitor this portion of the work.
This summary should be used in conjunction with the entire report for design purposes. It should
be recognized that details were not included or fully developed in this section, and the report must
be read in its entirety for a comprehensive understanding of the items contained herein. The section
titled GENERAL COMMENTS should be read for an understanding of the report limitations.
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GEOTECHNICAL ENGINEERING REPORT
Standard at Fort Collins
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
Terracon Project No. 20165058
September 6, 2016
1.0 INTRODUCTION
This report presents the results of our geotechnical engineering services performed for the
proposed Standard at Fort Collins student housing development to be located northeast of the
intersection of West Prospect Road and Sheely Drive in Fort Collins, Colorado (Exhibit A-1). The
purpose of these services is to provide information and geotechnical engineering
recommendations relative to:
n subsurface soil and bedrock conditions n foundation design and construction
n groundwater conditions n floor slab design and construction
n grading and drainage n pavement construction
n lateral earth pressures n earthwork
n seismic considerations
Our geotechnical engineering scope of work for this project included the initial site visit, the
advancement of 7 test borings to depths ranging from approximately 35 to 63½ feet below existing
site grades, surface seismic testing (ReMI), pressuremeter testing within 2 of the test borings,
laboratory testing for soil engineering properties and engineering analyses to provide foundation,
floor system and pavement design and construction recommendations.
Logs of the borings along with an Exploration Plan (Exhibit A-2) are included in Appendix A. The
results of the laboratory testing performed on soil and bedrock samples obtained from the site
during the field exploration are included in Appendix B.
2.0 PROJECT INFORMATION
2.1 Project Description
Item Description
Site layout Refer to the Exploration Plan (Exhibit A-2 in Appendix A)
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
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Item Description
Structures
Information provided to us indicates the project will include
construction of a parking structure and two (2) student housing
structures. The existing structures currently occupying the site will
be demolished and removed prior to the proposed construction. An
access drive will be constructed from West Prospect Road to the
center of the site.
Parking Structure: This precast structure will consist of 524 parking
spaces on 6 levels of parking at 28,800 square feet per level. A
rooftop pool and amenity terrace is also planned for the upper level
of the structure. One basement level is planned for the parking
structure with the other five levels extending above grade.
Building A: This building will consist of 5 levels of residential with a
footprint of about 51,900 square feet. No basement is planned for
this building.
Building B: This building will include 5 levels of residential with 4
levels over a podium. Also, below-grade parking is possible for this
building.
A sky bridge is also planned between the two buildings.
Maximum loads
Wood on grade wall loads (provided): 2 to 7 klf
Transfer podium column loads (provided): 300 to 500 kips
Parking deck wall loads (provided): 35 to 65 klf
Parking deck column loads (provided): 300 to 1000 kips
Grading in building area
We anticipate cuts and fills on the order of 10 feet or less will be
required to adequately complete demolition of existing buildings,
utilities, and other site preparation efforts. The basement level for
the parking structure will likely require excavation to depths of about
12 to 15 feet.
Traffic loading
We anticipate traffic loading will consist of passenger vehicles,
refuse disposal vehicles, delivery trucks, and various other types of
vehicles.
2.2 Site Location and Description
Item Description
Location The project site is located at northeast of West Prospect Road and
Sheely Drive in Fort Collins, Colorado.
Existing site features
The Blue Ridge Apartment complex currently occupies the northern
portion of the proposed project area. Single-family residences are
present along the southern edge of the proposed development area.
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Item Description
Surrounding developments
There are several properties included within the project site currently
occupied by single-family and multi-family residences. The site is
surrounded by residential development and structures associated
with the Colorado State University main campus to the north.
Current ground cover The ground surface in our areas of exploration were covered with
landscaping materials, asphalt, bare ground and gravel-surfacing.
Existing topography The site is relatively flat.
3.0 SUBSURFACE CONDITIONS
3.1 Typical Subsurface Profile
Specific conditions encountered at each boring location are indicated on the individual boring logs
included in Appendix A. Stratification boundaries on the boring logs represent the approximate
location of changes in soil types; in-situ, the transition between materials may be gradual. Based
on the results of the borings, subsurface conditions on the project site can be generalized as
follows:
Material Description Approximate Depth to
Bottom of Stratum Consistency/Density/Hardness
Fill materials consisting of lean clay,
sand, and gravel (Boring Nos. 1
through 4)
About 5½ feet below existing
site grades. --
Clayey sand to sandy clay About 15 feet below existing
site grades. Dense to very dense
Lean clay with varying amounts of
sand
About 25½ to 42 feet below
existing site grades
Medium stiff to stiff
Sand, well to poorly graded About 15½ 35 feet below
existing site grades
Loose to dense
Interbedded sandstone and
claystone bedrock
To the maximum depth of
exploration of about 63½ feet. Weathered to very hard
3.2 Laboratory Testing
Representative soil samples were selected for swell-consolidation testing and exhibited slight to
2.5 percent compression when wetted. A sample of lean clay soil exhibited an unconfined
compressive strength of approximately 3,000 pounds per square foot (psf). Samples of site soils
and bedrock selected for plasticity testing exhibited low to moderate plasticity with liquid limits
ranging from non-plastic to 47 and plasticity indices ranging from non-plastic to 30. Laboratory
test results are presented in Appendix B.
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3.3 Corrosion Protection (Water-Soluble Sulfates)
Results of water-soluble sulfate testing indicate that ASTM Type II, portland cement should be
specified for all project concrete on and below grade. Foundation concrete should be designed
for moderate sulfate exposure in accordance with the provisions of the ACI Design Manual,
Section 318, Chapter 4.
Terracon was requested to perform laboratory testing on soil and bedrock samples collected from
the site to determine the potential corrosive characteristics of the on-site soils and bedrock with
respect to contact with the various underground materials that will be used for project
construction. Laboratory test results for select samples tested exhibited the following properties:
Sample
Identification
Water-Soluble
Sulfate
Redox
Potential Sulfide
Water-
Soluble
Chloride
Electrical
Resistivity1 pH
(%) (mV) (Presence) (%) (ohm-cm)
Boring No. 1
at 24 feet 0.007 302 Negative 0.0015 1,372 8
Boring No. 3
at 9 feet
0.005 282 Negative 0.005 1,437 8
Boring No. 7
at 49 feet
0.034 269 Negative 0.0009 975 8
1. Resistivity determined on saturated samples.
Terracon recommends providing the laboratory test results regarding potential corrosive
characteristics of the on-site soils and bedrock materials encountered below this site to a
corrosion specialist to interpret the data and incorporate the test results into the final design of
the selected foundation system.
3.4 Groundwater
The boreholes were observed while drilling and after completion for the presence and level of
groundwater. In addition, delayed water levels were also obtained in some borings. The water levels
observed in the boreholes are noted on the attached boring logs, and are summarized below:
Boring Number Depth to groundwater
while drilling, ft.
Depth to groundwater
on 7/14/16, ft.
Elevation of
groundwater on 7/14/16,
ft.
1 19 14.4 5008.5
2 21 19.4 5004.1
3 19 18.7 5002.9
4 19 Backfilled after drilling Backfilled after drilling
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Boring Number Depth to groundwater
while drilling, ft.
Depth to groundwater
on 7/14/16, ft.
Elevation of
groundwater on 7/14/16,
ft.
5 24 Backfilled after drilling Backfilled after drilling
6 21 22.0 5005.1
7 20 20.6 5004
These observations represent groundwater conditions at the time of the field exploration, and may
not be indicative of other times or at other locations. Groundwater level fluctuations occur due to
seasonal variations in the water levels present in nearby water features, amount of rainfall, runoff
and other factors not evident at the time the borings were performed. Therefore, groundwater
levels during construction or at other times in the life of the proposed structures may be higher or
lower than the levels indicated on the boring logs. The possibility of groundwater level fluctuations
should be considered when developing the design and construction plans for the project.
Fluctuations in groundwater levels can best be determined by implementation of a groundwater
monitoring plan. Such a plan would include installation of groundwater piezometers, and periodic
measurement of groundwater levels over a sufficient period of time. If the proposed project will
include multiple levels of below-grade construction that will encroach upon measured groundwater
levels, Terracon is available to assist with the design of the excavation shoring, construction
dewatering, and/or permanent dewatering systems.
3.5 Seismic Refraction
In addition to soil borings, surface seismic testing was performed (Exhibit A-2). Terracon utilized
the SeisOpt®ReMi™ method to develop the full-depth (100 feet) shear wave profile at the site for
use in determining the seismic site class as described in the 2009/2012 International Building Code
(IBC). This method employs non-linear optimization technology to derive one-dimensional S-wave
velocities from refraction microtremor (ambient noise) recordings using a seismograph and low
frequency, refraction geophones. We performed a single ReMi survey) across the site due to access
constraints. We utilized 12 receivers (geophones) set along a relatively straight-line array with a
15±foot receiver spacing for a 300±foot long transverse. A number of unfiltered, 30 second records
were collected using the background noise (traffic).
The collected data, the response spectrum in the 5 to 40 Hz range, was processed using computer
software (SeisOpt® ReMi™ by Optim, LLC) with the results plotted as a conventional shear wave
vs. depth profile. The shear wave dispersion curve and the selected point plot of the data is
presented as (Exhibit A-12).
3.6 Pressuremeter Testing
Pressuremeter testing was performed at two (2) locations (PMT 1 and PMT 2 as shown on Exhibit
A-2). Two (2) tests were performed at PMT 1 and three (3) tests were performed at PMT 2 at
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
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varying depths within the bedrock strata. Pressuremeter testing was performed using a cylindrical
probe with an inner rubber membrane and an outer protective sheath that were inflated using
fluid, against the sidewalls of the borings at predetermined depths. The deformation of the bearing
strata was measured periodically while increasing pressures until the bedrock failed in shear.
Using the data collected during pressuremeter testing, in-situ strength parameters were obtained
including Young’s Moduli, limit pressures, and Menard deformation moduli. Using these values, the
soil and bedrock was modeled more accurately than conventional methods, and values for deep
foundation design and construction criteria were calculated. Pressuremeter test results are included
as Exhibits A-13 through A-17 of this report.
4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION
4.1 Geotechnical Considerations
Based on subsurface conditions encountered in the borings, the site appears suitable for the
proposed construction from a geotechnical point of view provided certain precautions and design
and construction recommendations described in this report are followed. We have identified
geotechnical conditions that could impact design and construction of the proposed structures,
pavements, and other site improvements.
4.1.1 Existing, Undocumented Fill
As previously noted, existing undocumented fill was encountered to depths up to about 5½ feet
in the borings drilled at the site Blue Ridge Apartment site (Boring Nos. 1 through 4). We do not
possess any information regarding whether the fill was placed under the observation of a
geotechnical engineer. Considering the site has been developed for many years prior to our study,
it is also likely other areas of the site are underlain by fill materials of varying thickness.
Support of foundations, floor slabs, and pavements on or above existing fill soils is discussed in
this report. There is an inherent risk for the owner that compressible fill or unsuitable material
within or buried by the fill will not be discovered. This risk of unforeseen conditions cannot be
eliminated without completely removing the existing fill, but can be reduced by performing
additional testing and evaluation.
4.1.2 Groundwater
As previously stated, groundwater was measured at depths ranging from about 14.4 to 22 feet
below existing site grades. Depending on the final design and depth of below-grade areas,
groundwater may impact construction as well as require management throughout the life of the
project. In addition, depending on final design, Terracon recommends maintaining a separation
of at least 3 feet between the bottom of proposed below-grade footing foundations and measured
groundwater levels. It is also possible and likely that groundwater levels below this site may rise
as water levels in nearby water features rise.
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September 8, 2016 ■ Terracon Project No. 20165058
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4.1.3 Expansive Soils and Bedrock
Laboratory testing indicates the native clay soils and claystone bedrock exhibited low expansive
potential at the samples in-situ moisture content. However, it is our opinion these materials will
exhibit a higher expansive potential if the clays and claystone undergo a significant loss of
moisture.
This report provides recommendations to help mitigate the effects of soil shrinkage and
expansion. However, even if these procedures are followed, some movement and cracking in
the structures, pavements, and flatwork should be anticipated. The severity of cracking and other
damage such as uneven floor slabs will probably increase if any modification of the site results in
excessive wetting or drying of the clay soils and/or claystone bedrock. Eliminating the risk of
movement and distress is generally not feasible, but it may be possible to further reduce the risk
of movement if significantly more expensive measures are used during construction. It is
imperative the recommendations described in section 4.2.8 Grading and Drainage of this report
be followed to reduce movement.
4.1.4 Permanent Dewatering
Preliminary site concepts indicate the proposed construction may extend below the observed
groundwater levels. Thus, permanent dewatering may be needed to lower groundwater levels
below permanent excavations. We recommend that on a long term basis, groundwater levels be
maintained at least 3 feet below the floor slab.
If a permanent dewatering system is judged necessary by the project team, we suggest the
dewatering system consist of a combination of drains and sumps. The configuration of the system
will depend on the size of the below-grade structures. The locations of the drains and/or sumps
must consider maintenance accessibility. Although our services did not include an official design
of the dewatering system, we have included some conceptual drain considerations for preliminary
planning purposes. Terracon is available to assist with design of temporary and/or permanent
dewatering system for this project, if needed.
A possible configuration would be a subsurface drain around the exterior of the structures. The
drain pipe should be properly sized, perforated PVC or other type of hard pipe embedded in
properly graded drainage gravel. The invert of the drain pipe should be at least 3 feet below the
bottom of the floor slab the proposed structures. The drain pipe should discharge into a sump(s)
accessible within the below-grade areas.
The drainage gravel should extend vertically over the drain pipes to at least 2 feet above the
highest groundwater levels observed in the soil borings. Thus, the drain gravel will likely extend
into the foundation wall backfill. The foundation walls adjacent to the drain gravel should be
properly water-proofed.
Provision must be made to prevent migration or piping of the native soils into the drainage gravel.
Ideally this would be by a properly graded sand filter. Alternatively, a filter fabric could be used.
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If a filter fabric is used, we strongly recommend that installation be in the dry. That is, the
Contractor should dewater the excavation so that it is free of standing water during installation of
the drain components.
Other issues to be considered include:
n Disposition of the developed water, which could be to a storm water detention basin.
Evaluation of the amount of water likely to be discharged from a permanent dewatering
system was not included in our scope of services for this study but should be evaluated,
if a permanent dewatering system is selected.
n Possible permitting requirements. If the dewatering system is considered to be a well,
permits would be required at a minimum from the Colorado State Engineer’s Office and
the State of Colorado Department of Public Health and Environment. The permits, should
they be needed, will require regular reporting of discharge water quality. Adequate time
should be included in the project schedule to obtain the permits.
n Maintenance. All permanent dewatering systems require regular maintenance to assure
the drains and pumps are in proper operating condition. Underground drains associated
with the system should have cleanouts so that the system can be flushed/ cleaned
periodically as underground dewatering systems can become clogged with anaerobic
microbial and other growth. The cleanout locations should be readily accessible and a
source of high pressure (water main pressure) water available to flush the drains.
n Monitoring. By their nature, permanent dewatering systems tend to be “out of sight and
out of mind”. Therefore, we recommend that there be a monitoring system to alert
maintenance personnel if the pumps have failed and water levels are rising in the sumps.
A simple monitoring system would be to install a water detector in a sump about 2 feet
below the bottom of the rail pit floor slab that would activate a flashing warning light in the
control building.
4.1.5 Foundation and Floor Slab Recommendations
The proposed parking structure and buildings that will require heavy to moderate foundation loads
may be supported on either drilled piers bottomed in bedrock or helical piles bottomed in bedrock.
For the 1 and 2-story buildings that will require comparatively low foundation loads, we believe a
spread footing foundation system bearing on properly prepared on-site soils or properly placed
engineered fill can be utilized for support of these structures. We recommend a slab-on-grade for
the interior floor system of the proposed buildings. Even when bearing on properly prepared soils,
movement of the slab-on-grade floor system is possible should the subgrade soils undergo an
increase in moisture content. We estimate movement of about 1 inch is possible. If the owner
cannot accept the risk of slab movement, a structural floor should be used.
Geotechnical Engineering Report
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4.2 Earthwork
The following presents recommendations for site preparation, demolition, excavation, subgrade
preparation and placement of engineered fills on the project. All earthwork on the project should
be observed and evaluated by Terracon on a full-time basis. The evaluation of earthwork should
include observation of over-excavation operations, testing of engineered fills, subgrade
preparation, subgrade stabilization, and other geotechnical conditions exposed during the
construction of the project. Terracon should be retained on a full-time basis to confirm complete
removal and recompaction of the existing, undocumented fill below portions of the site.
4.2.1 Site Preparation
Prior to placing any fill, strip and remove existing vegetation, any undocumented existing fill, and
any other deleterious materials from the proposed construction areas. Stripped organic materials
should be wasted from the site or used to re-vegetate landscaped areas or exposed slopes after
completion of grading operations. Prior to the placement of fills, the site should be graded to create
a relatively level surface to receive fill, and to provide for a relatively uniform thickness of fill beneath
proposed structures.
4.2.2 Demolition
Demolition of the existing Blue Ridge Apartments and residences should include complete removal
of all foundation systems, below-grade structural elements, pavements, and exterior flat work within
the proposed construction area. This should include removal of any utilities to be abandoned along
with any loose utility trench backfill or loose backfill found adjacent to existing foundations. All
materials derived from the demolition of existing structures and pavements should be removed from
the site. The types of foundation systems supporting the existing structures are not known. If some
or all of the existing buildings are supported by drilled piers, the existing piers should be truncated
a minimum depth of 3 feet below areas of planned new construction.
Consideration could be given to re-using the asphalt and concrete provided the materials are
processed and uniformly blended with the on-site soils. Asphalt and/or concrete materials should
be processed to a maximum size of 2-inches and blended at a ratio of 30 percent asphalt/concrete
to 70 percent of on-site soils.
4.2.3 Excavation
It is anticipated that excavations for the proposed construction can be accomplished with
conventional earthmoving equipment. The soils to be excavated can vary significantly across the
site as their classifications are based solely on the materials encountered in widely-spaced
exploratory test borings. The contractor should verify that similar conditions exist throughout the
proposed area of excavation. If different subsurface conditions are encountered at the time of
construction, the actual conditions should be evaluated to determine any excavation modifications
necessary to maintain safe conditions.
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Although evidence of fills or underground facilities such as septic tanks, vaults, and utilities was not
observed during the site reconnaissance, such features could be encountered during construction.
If unexpected fills or underground facilities are encountered, such features should be removed and
the excavation thoroughly cleaned prior to backfill placement and/or construction.
Any over-excavation that extends below the bottom of proposed footing foundation elevations
should extend laterally beyond all edges of the foundations at least 8 inches per foot of over-
excavation depth below the foundation base elevation. The over-excavation should be backfilled
to the foundation base elevation in accordance with the recommendations presented in this report.
Depending upon depth of excavation and seasonal conditions, surface water infiltration and/or
groundwater may be encountered in excavations on the site. It is anticipated that pumping from
sumps may be utilized to control water within excavations. The subgrade soil conditions should be
evaluated during the excavation process and the stability of the soils determined at that time by the
contractors’ Competent Person. Slope inclinations flatter than the OSHA maximum values may
have to be used. The individual contractor(s) should be made responsible for designing and
constructing stable, temporary excavations as required to maintain stability of both the excavation
sides and bottom. All excavations should be sloped or shored in the interest of safety following
local, and federal regulations, including current OSHA excavation and trench safety standards. If
any excavation, including a utility trench, is extended to a depth of more than 20 feet, it will be
necessary to have the side slopes and/or shoring system designed by a professional engineer.
As a safety measure, it is recommended that all vehicles and soil piles be kept a minimum lateral
distance from the crest of the slope equal to the slope height. The exposed slope face should be
protected against the elements
4.2.4 Subgrade Preparation
After the undocumented existing fill and demolition debris has been removed from the
construction area, the top 8 inches of the exposed ground surface should be scarified, moisture
conditioned, and recompacted to at least 95 percent of the maximum dry unit weight as
determined by ASTM D698 before any new fill or foundation or pavement is placed.
If pockets of soft, loose, or otherwise unsuitable materials are encountered at the bottom of the
foundation excavations and it is inconvenient to lower the foundations, the proposed foundation
elevations may be reestablished by over-excavating the unsuitable soils and backfilling with
compacted engineered fill or lean concrete.
After the bottom of the excavation has been compacted, engineered fill can be placed to bring the
building pad and pavement subgrade to the desired grade. Engineered fill should be placed in
accordance with the recommendations presented in subsequent sections of this report.
The stability of the subgrade may be affected by precipitation, repetitive construction traffic or
other factors. If unstable conditions develop, workability may be improved by scarifying and
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drying. Alternatively, over-excavation of wet zones and replacement with granular materials may
be used, or crushed gravel and/or rock can be tracked or “crowded” into the unstable surface soil
until a stable working surface is attained. Lightweight excavation equipment may also be used to
reduce subgrade pumping.
4.2.5 Fill Materials and Placement
The on-site soils or approved granular and low plasticity cohesive imported materials may be used
as fill material. Granular fill placed below floor slabs should meet the specifications of the Colorado
Department of Transportation (CDOT) Class 1 structure backfill, presented in the following table:
Gradation Percent finer by weight (ASTM C136)
2” 100
No. 4 Sieve 30-100
No. 50 Sieve 10-60
No. 200 Sieve 5-20
Soil Properties Values
Liquid Limit 35 (max.)
Plastic Limit 6 (max.)
The soil removed from this site that is free of organic or objectionable materials, as defined by a
field technician who is qualified in soil material identification and compaction procedures, can be
re-used as fill for the building pad and pavement subgrade. It should be noted that on-site soils
will require reworking to adjust the moisture content to meet the compaction criteria.
Imported soils (if required) should meet the following material property requirements:
Gradation Percent finer by weight (ASTM C136)
4” 100
3” 70-100
No. 4 Sieve 50-100
No. 200 Sieve 50 (max.)
Soil Properties Values
Liquid Limit 35 (max.)
Plastic Limit 6 (max.)
Maximum Expansive Potential (%) Non-expansive1
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Soil Properties Values
1. Measured on a sample compacted to approximately 95 percent of the maximum dry unit weight as
determined by ASTM D698 at optimum moisture content. The sample is confined under a 100 psf
surcharge and submerged.
4.2.6 Compaction Requirements
Engineered fill should be placed and compacted in horizontal lifts, using equipment and
procedures that will produce recommended moisture contents and densities throughout the lift.
Item Description
Fill lift thickness
9 inches or less in loose thickness when heavy, self-
propelled compaction equipment is used
4 to 6 inches in loose thickness when hand-guided
equipment (i.e. jumping jack or plate compactor) is used
Minimum compaction requirements 95 percent of the maximum dry unit weight as
determined by ASTM D698
Moisture content cohesive soil (clay) -1 to +3 % of the optimum moisture content
Moisture content cohesionless soil (sand) -3 to +3 % of the optimum moisture content
1. We recommend engineered fill be tested for moisture content and compaction during placement.
Should the results of the in-place density tests indicate the specified moisture or compaction limits
have not been met, the area represented by the test should be reworked and retested as required
until the specified moisture and compaction requirements are achieved.
2. Specifically, moisture levels should be maintained low enough to allow for satisfactory compaction to
be achieved without the fill material pumping when proofrolled.
3. Moisture conditioned clay materials should not be allowed to dry out. A loss of moisture within these
materials could result in an increase in the material’s expansive potential. Subsequent wetting of
these materials could result in undesirable movement.
4.2.7 Utility Trench Backfill
All trench excavations should be made with sufficient working space to permit construction including
backfill placement and compaction.
All underground piping within or near the proposed structures should be designed with flexible
couplings, so minor deviations in alignment do not result in breakage or distress. Utility knockouts
in foundation walls should be oversized to accommodate differential movements. It is imperative
that utility trenches be properly backfilled with relatively clean materials. If utility trenches are
backfilled with relatively clean granular material, they should be capped with at least 18 inches of
cohesive fill in non-pavement areas to reduce the infiltration and conveyance of surface water
through the trench backfill.
Utility trenches are a common source of water infiltration and migration. All utility trenches that
penetrate beneath the buildings should be effectively sealed to restrict water intrusion and flow
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through the trenches that could migrate below the buildings. We recommend constructing an
effective clay “trench plug” that extends at least 5 feet out from the face of the building exteriors.
The plug material should consist of clay compacted at a water content at or above the soil’s optimum
water content. The clay fill should be placed to completely surround the utility line and be compacted
in accordance with recommendations in this report.
It is strongly recommended that a representative of Terracon provide full-time observation and
compaction testing of trench backfill within building and pavement areas.
4.2.8 Grading and Drainage
All grades must be adjusted to provide effective drainage away from the proposed building and
nearby existing structures during construction and maintained throughout the life of the proposed
project. Infiltration of water into foundation excavations must be prevented during construction.
Landscape irrigation adjacent to foundations should be minimized or eliminated. Water permitted
to pond near or adjacent to the perimeter of the structures (either during or post-construction) can
result in significantly higher soil movements than those discussed in this report. As a result, any
estimations of potential movement described in this report cannot be relied upon if positive
drainage is not obtained and maintained, and water is allowed to infiltrate the fill and/or subgrade.
Exposed ground (if any) should be sloped at a minimum of 10 percent grade for at least 10 feet
beyond the perimeter of the proposed buildings, where possible. The use of swales, chases
and/or area drains may be required to facilitate drainage in unpaved areas around the perimeter
of the buildings. Backfill against foundations and exterior walls should be properly compacted and
free of all construction debris to reduce the possibility of moisture infiltration. After construction
of the proposed buildings and prior to project completion, we recommend verification of final
grading be performed to document positive drainage, as described above, has been achieved.
Flatwork and pavements will be subject to post-construction movement. Maximum grades
practical should be used for paving and flatwork to prevent areas where water can pond. In
addition, allowances in final grades should take into consideration post-construction movement
of flatwork, particularly if such movement would be critical. Where paving or flatwork abuts the
structures, care should be taken that joints are properly sealed and maintained to prevent the
infiltration of surface water.
Planters located adjacent to structures should preferably be self-contained. Sprinkler mains and
spray heads should be located a minimum of 5 feet away from the building line(s). Roof drains
should discharge on to pavements or be extended away from the structures a minimum of 10 feet
through the use of splash blocks or downspout extensions. A preferred alternative is to have the
roof drains discharge by solid pipe to storm sewers or to a detention pond or other appropriate
outfall.
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4.2.9 Exterior Slab Design and Construction
Exterior slabs on-grade, exterior architectural features, and utilities founded on, or in backfill or
the site soils will likely experience some movement due to the volume change of the material.
Potential movement could be reduced by:
n Minimizing moisture increases in the backfill;
n Controlling moisture-density during placement of the backfill;
n Using designs which allow vertical movement between the exterior features and
adjoining structural elements; and
n Placing control joints on relatively close centers.
4.3 Foundations
The proposed parking structure and multi-story buildings that will require heavy to moderate
foundation loads may be supported on either drilled piers bottomed in bedrock or helical piles
bottomed in bedrock. Based on the building loads provided, 1 and 2-story structures will impart
comparatively lower foundation loads; thus, we believe a spread footing foundation system
bearing on properly prepared on-site soils or properly placed engineered fill can be utilized for
support of these structures. Design recommendations for foundations for the proposed structures
and related structural elements are presented in the following sections.
4.3.1 Drilled Piers Bottomed in Bedrock - Design Recommendations
Description Value
Estimated pier length1 30 to 50 feet
Minimum pier diameter 18 inches
Minimum bedrock embedment 2 6 feet
Maximum allowable end-bearing pressure 60,000 psf
Allowable skin friction (for portion of pier embedded into bedrock) 2,500 psf
Void thickness 4 inches
1. Estimated from existing ground level.
2. Drilled piers should be embedded into hard or very hard bedrock materials. Actual structural
loads and pier diameters may dictate embedment deeper than the recommended minimum
penetration.
Site grading details were not fully understood at the time we prepared this report. If below grade
areas are planned in the proposed building areas, drilled pier lengths will likely be reduced. Piers
should be considered to work in group action if the horizontal spacing is less than three pier
diameters. A minimum practical horizontal clear spacing between piers of at least three diameters
should be maintained, and adjacent piers should bear at the same elevation. The capacity of
individual piers must be reduced when considering the effects of group action. Capacity reduction
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is a function of pier spacing and the number of piers within a group. If group action analyses are
necessary, capacity reduction factors can be provided for the analyses.
To satisfy forces in the horizontal direction using LPILE, piers may be designed for the following
lateral load criteria:
Parameters Clay Sand and
Gravel Bedrock
LPILE soil type Soft clay
Sand
(submerged)
Stiff clay
Effective unit weight (pcf) above groundwater 120 125 125
Effective unit weight (pcf) below groundwater 60 65 --
Average undrained shear strength (psf) 500 N/A 9,000
Average angle of internal friction, F (degrees) N/A 35 N/A
Coefficient of subgrade reaction, k (pci)*
100 - static
30 - cyclic
60
2,000- static
800 – cyclic
Strain, e50 (%) 0.010 N/A 0.004
1. For purposes of LPILE analysis, assume a groundwater depth of about 15 feet below existing
ground surface (approximately Elev. 5,007 feet).
Piers should have minimum diameter of 18 inches and a preferred maximum length to diameter
ratio (L/D) of 20 to 25, with 30 considered the typical limit. Larger pier diameters may be needed
to accommodate actual foundation loads and other structural design requirements.
4.3.2 Drilled Piers Bottomed in Bedrock - Construction Considerations
Drilling to design depth should be possible with conventional single-flight power augers on the
majority of the site; however, specialized drilling equipment may be required for very hard bedrock
layers. In addition, caving soils and groundwater indicate that temporary steel casing will be
required to properly drill the piers prior to concrete placement.
Groundwater should be removed from each pier hole prior to concrete placement. Pier concrete
should be placed immediately after completion of drilling and cleaning. If pier concrete cannot be
placed in dry conditions, a tremie should be used for concrete placement. Free-fall concrete
placement in piers will only be acceptable if provisions are taken to avoid striking the concrete on
the sides of the hole or reinforcing steel. The use of a bottom-dump hopper, or an elephant's
trunk discharging near the bottom of the hole where concrete segregation will be minimized, is
recommended. Due to potential sloughing and raveling, foundation concrete quantities may
exceed calculated geometric volumes.
Casing should be withdrawn in a slow continuous manner maintaining a sufficient head of
concrete to prevent infiltration of water or caving soils or the creation of voids in pier concrete.
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Pier concrete should have a relatively high fluidity when placed in cased pier holes or through a
tremie. Pier concrete with slump in the range of 5 to 7 inches is recommended.
We recommend the sides of each pier should be mechanically roughened in the claystone bearing
strata. This should be accomplished by a roughening tooth placed on the auger. Shaft bearing
surfaces must be cleaned prior to concrete placement. Excessive remolding and caking of
bedrock on pier walls must be removed. A representative of Terracon should observe the bearing
surface and shaft configuration.
4.3.3 Helical Pile Foundations
We believe helical piles bottomed in bedrock are a viable alternative appropriate for support of
the proposed project. The helical pile foundation system will offer reduced drilling lengths
(compared to conventional drilled piers) by anchoring into the upper portions of the bedrock
versus competent bedrock. In addition, the installation torque can be used to verify the capacity
of a helical pile, which will provide an indication of allowable bearing pressure and may result in
reduced pile lengths. Design recommendations for helical pile foundations and related structural
elements are presented in the following paragraphs.
Description Value
Anticipated pile length About 20 to 50 feet from existing
grade(s)
Net allowable end-bearing pressure1
Bottomed in site soils 10,000 psf
Bottomed in weathered bedrock 25,000 psf
Bottomed in competent, hard to very hard, bedrock 60,000 psf
Individual pile settlement About ½ inch
1. The design bearing pressure applies to dead loads plus design live load conditions. The design
bearing pressure may be increased by one-third when considering total loads that include wind
or seismic conditions.
We do not recommend using vertically installed helical piles to resist lateral loads without
approved lateral load test data, as these types of foundations are typically designed to resist axial
loads. Only the horizontal component of the allowable axial load should be considered to resist
the lateral loading and only in the direction of the batter. Terracon should be retained to observe
helical pile installation to verify that proper bearing materials have been encountered during
installation.
If a helical pile foundation system is selected by the project team, we recommend the helical pile
designer follow the recommendations presented in Chapter 18 of the current International Building
Code (IBC). We recommend the helical bearing plates for each helical pile bear in the design
bearing stratum encountered below the site. The helical pile designer should select the size and
number of helical bearing plates for each helical pile based on planned loads and bearing materials
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described in our exploratory boring logs. Torque measurements during installation of helical piles
should be used to verify the axial capacity of the helical piles. We recommend the helical pile
installation contractor provide confirmation that the installation equipment has been calibrated within
one year of installation at this project. The helical foundations should be installed per the
manufacturer’s recommendations.
4.3.4 Spread Footings - Design Recommendations
Description Values
Bearing material Properly prepared on-site soil
Maximum allowable bearing pressure 1 2,000 psf
Lateral earth pressure coefficients 2
Active, Ka = 0.35
Passive, Kp = 2.88
At-rest, Ko = 0.52
Sliding coefficient 2 µ = 0.35
Moist soil unit weight ɣ = 120 pcf
Minimum embedment depth below finished
grade 3 30 inches
Estimated total movement 4 About 1 inch
Estimated differential movement 4 About ½ to ¾ of total movement
1. The recommended maximum allowable bearing pressure assumes any unsuitable fill or soft soils, if
encountered, will be over-excavated and replaced with properly compacted engineered fill. The
design bearing pressure applies to a dead load plus design live load condition. The design bearing
pressure may be increased by one-third when considering total loads that include wind or seismic
conditions.
2. The lateral earth pressure coefficients and sliding coefficients are ultimate values and do not include
a factor of safety. The foundation designer should include the appropriate factors of safety.
3. For frost protection and to reduce the effects of seasonal moisture variations in the subgrade soils.
The minimum embedment depth is for perimeter footings beneath unheated areas and is relative to
lowest adjacent finished grade, typically exterior grade.
4. The estimated movements presented above are based on the assumption that the maximum footing
size is 5 feet for column footings and 3 feet for continuous footings.
Footings should be proportioned to reduce differential foundation movement. As discussed, total
movement resulting from the assumed structural loads is estimated to be on the order of about 1
inch. Additional foundation movements could occur if water from any source infiltrates the
foundation soils; therefore, proper drainage should be provided in the final design and during
construction and throughout the life of the structure. Failure to maintain the proper drainage as
recommended in the 4.2.8 Grading and Drainage section of this report will nullify the movement
estimates provided above.
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4.3.5 Spread Footings - Construction Considerations
Spread footing construction should only be considered for lightly to moderately-loaded structures
and if the estimated foundation movement can be tolerated. Subgrade soils beneath footings
should be moisture conditioned and compacted as described in the 4.2 Earthwork section of this
report. The moisture content and compaction of subgrade soils should be maintained until
foundation construction.
Footings and foundation walls should be reinforced as necessary to reduce the potential for distress
caused by differential foundation movement. Unstable subgrade conditions are anticipated as
excavations approach the groundwater surface. Unstable surfaces will need to be stabilized prior
to backfilling excavations and/or constructing the building foundation, floor slab and/or project
pavements. The use of angular rock, recycled concrete and/or gravel pushed or “crowded” into the
yielding subgrade is considered suitable means of stabilizing the subgrade. The use of geogrid
materials in conjunction with gravel could also be considered and could be more cost effective.
Unstable subgrade conditions should be observed by Terracon to assess the subgrade and
provide suitable alternatives for stabilization. Stabilized areas should be proof-rolled prior to
continuing construction to assess the stability of the subgrade.
Foundation excavations should be observed by Terracon. If the soil conditions encountered differ
significantly from those presented in this report, supplemental recommendations will be required.
4.4 Seismic Considerations
Code Used Site Classification
2012 International Building Code (IBC) 1 D 2
1. In general accordance with the 2012 International Building Code, Table 1613.5.2.
2. The 2012 International Building Code (IBC) requires a site soil profile determination extending a
depth of 100 feet for seismic site classification. The current scope requested includes a shear wave
profile to estimate site class. The seismic refraction results are presented in Appendix A.
4.5 Floor Systems
A slab-on-grade may be utilized for the interior floor system for the proposed buildings, provided
the floor slabs are constructed on at least 12 inches of CDOT Class 1 structure backfill and the
existing fill is completely removed and recompacted below the buildings. All backfill should be
placed following the recommendations in this report for minimum compaction and moisture
content. If the estimated movement cannot be tolerated, a structurally-supported floor system,
supported independent of the subgrade materials, is recommended.
Subgrade soils beneath interior and exterior slabs should be scarified to a depth of at least 8
inches, moisture conditioned and compacted. The moisture content and compaction of subgrade
soils should be maintained until slab construction is completed.
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4.5.1 Floor System - Design Recommendations
Even when bearing on properly prepared soils, movement of the slab-on-grade floor system is
possible should the subgrade soils undergo an increase in moisture content. We estimate
movement of about 1 inch is possible. If the owner cannot accept the risk of slab movement, a
structural floor should be used. If conventional slab-on-grade is utilized, the subgrade soils should
be over-excavated and prepared as presented in the 4.2 Earthwork section of this report.
For structural design of concrete slabs-on-grade subjected to point loadings, a modulus of
subgrade reaction of 200 pounds per cubic inch (pci) may be used for floors supported on
imported CDOT Class 1 structure backfill.
Additional floor slab design and construction recommendations are as follows:
n Positive separations and/or isolation joints should be provided between slabs and all
foundations, columns, or utility lines to allow independent movement.
n Control joints should be saw-cut in slabs in accordance with ACI Design Manual, Section
302.1R-37 8.3.12 (tooled control joints are not recommended) to control the location and
extent of cracking.
n Interior utility trench backfill placed beneath slabs should be compacted in accordance
with the recommendations presented in the 4.2 Earthwork section of this report.
n Floor slabs should not be constructed on frozen subgrade.
n The use of a vapor retarder should be considered beneath concrete slabs that will be
covered with wood, tile, carpet or other moisture sensitive or impervious floor coverings,
or when the slab will support equipment sensitive to moisture. When conditions warrant
the use of a vapor retarder, the slab designer and slab contractor should refer to ACI
302 for procedures and cautions regarding the use and placement of a vapor retarder.
n Other design and construction considerations, as outlined in the ACI Design Manual,
Section 302.1R are recommended.
4.5.2 Floor Systems - Construction Considerations
Movements of slabs-on-grade using the recommendations discussed in previous sections of this
report will likely be reduced and tend to be more uniform. The estimates discussed above assume
that the other recommendations in this report are followed. Additional movement could occur
should the subsurface soils become wetted to significant depths, which could result in potential
excessive movement causing uneven floor slabs and severe cracking. This could be due to over
watering of landscaping, poor drainage, improperly functioning drain systems, and/or broken utility
lines. Therefore, it is imperative that the recommendations presented in this report be followed.
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4.6 Lateral Earth Pressures
Reinforced concrete walls with unbalanced backfill levels on opposite sides should be designed
for earth pressures at least equal to those indicated in the following table. Earth pressures will be
influenced by structural design of the walls, conditions of wall restraint, methods of construction
and/or compaction and the strength of the materials being restrained. Two wall restraint
conditions are shown. Active earth pressure is commonly used for design of free-standing
cantilever retaining walls and assumes wall movement. The "at-rest" condition assumes no wall
movement. The recommended design lateral earth pressures do not include a factor of safety
and do not provide for possible hydrostatic pressure on the walls.
EARTH PRESSURE COEFFICIENTS
Earth Pressure
Conditions
Coefficient for Backfill
Type
Equivalent Fluid
Density (pcf)
Surcharge
Pressure,
p1 (psf)
Earth
Pressure,
p2 (psf)
Active (Ka)
Imported Fill - 0.27
Lean Clay - 0.35
35
42
(0.27)S
(0.35)S
(35)H
(42)H
At-Rest (Ko)
Imported Fill - 0.43
Lean Clay - 0.52
56
62
(0.43)S
(0.52)S
(56)H
(70)H
Passive (Kp)
Imported Fill - 3.69
Lean Clay - 2.88
480
346
---
---
---
---
Applicable conditions to the above include:
n For active earth pressure, wall must rotate about base, with top lateral movements of about
0.002 H to 0.004 H, where H is wall height;
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n For passive earth pressure to develop, wall must move horizontally to mobilize resistance;
n Uniform surcharge, where S is surcharge pressure;
n In-situ soil backfill weight a maximum of 130 pcf;
n Horizontal backfill, compacted between 95 and 98 percent of maximum dry unit weight as
determined by ASTM D698;
n Loading from heavy compaction equipment not included;
n No hydrostatic pressures acting on wall;
n No dynamic loading;
n No safety factor included in soil parameters; and
n Ignore passive pressure in frost zone.
To control hydrostatic pressure behind the wall we recommend that a drain be installed at the
foundation wall with a collection pipe leading to a reliable discharge. If this is not possible, then
combined hydrostatic and lateral earth pressures should be calculated for lean clay backfill using
an equivalent fluid weighing 90 and 100 pcf for active and at-rest conditions, respectively. For
granular backfill, an equivalent fluid weighing 85 and 90 pcf should be used for active and at-rest,
respectively. These pressures do not include the influence of surcharge, equipment or floor
loading, which should be added. Heavy equipment should not operate within a distance closer
than the exposed height of retaining walls to prevent lateral pressures more than those provided.
4.3 Pavements
4.3.1 Pavements – Subgrade Preparation
On most project sites, the site grading is accomplished relatively early in the construction phase.
Fills are typically placed and compacted in a uniform manner. However as construction proceeds,
the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, or
rainfall/snow melt. As a result, the pavement subgrade may not be suitable for pavement
construction and corrective action will be required. The subgrade should be carefully evaluated
at the time of pavement construction for signs of disturbance or instability. We recommend the
pavement subgrade be thoroughly proofrolled with a loaded tandem-axle dump truck prior to final
grading and paving. All pavement areas should be moisture conditioned and properly compacted
to the recommendations in this report immediately prior to paving.
4.3.2 Pavements – Design Recommendations
Design of new privately-maintained pavements for the project has been based on the procedures
described by the National Asphalt Pavement Associations (NAPA) and the American Concrete
Institute (ACI).
We assumed the following design parameters for NAPA flexible pavement thickness design:
n Automobile Parking Areas
• Class I - Parking stalls and parking lots for cars and pick-up trucks, with
Equivalent Single Axle Load (ESAL) up to 7,000 over 20 years
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n Main Traffic Corridors
• Class II – Parking lots with a maximum of 10 trucks per day with Equivalent
Single Axle Load (ESAL) up to 27,000 over 20 years (Including trash trucks)
n Subgrade Soil Characteristics
• USCS Classification – CL, classified by NAPA as poor
We assumed the following design parameters for ACI rigid pavement thickness design based
upon the average daily truck traffic (ADTT):
n Automobile Parking Areas
• ACI Category A: Automobile parking with an ADTT of 1 over 20 years
n Main Traffic Corridors
• ACI Category A: Automobile parking area and service lanes with an ADTT of
up to 10 over 20 years
n Subgrade Soil Characteristics
• USCS Classification – CL
n Concrete modulus of rupture value of 600 psi
We should be contacted to confirm and/or modify the recommendations contained herein if actual
traffic volumes differ from the assumed values shown above.
Recommended alternatives for flexible and rigid pavements are summarized for each traffic area
as follows:
Traffic Area
Alternative
Recommended Pavement Thicknesses (Inches)
Asphaltic
Concrete
Surface
Aggregate
Base Course1
Portland
Cement
Concrete
Total
Automobile Parking
(NAPA Class I and ACI Category A)
A 4 6 -- 9
B - - 5 5
Service Lanes
(NAPA Class II and ACI Category A)
A 4½ 8 - 12½
B - - 6 6
Aggregate base course (if used on the site) should consist of a blend of sand and gravel which
meets strict specifications for quality and gradation. Use of materials meeting Colorado
Department of Transportation (CDOT) Class 5 or 6 specifications is recommended for aggregate
base course. Aggregate base course should be placed in lifts not exceeding 6 inches and
compacted to a minimum of 95 percent of the maximum dry unit weight as determined by ASTM
D698.
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Asphaltic concrete should be composed of a mixture of aggregate, filler and additives (if required)
and approved bituminous material. The asphalt concrete should conform to approved mix
designs stating the Superpave properties, optimum asphalt content, job mix formula and
recommended mixing and placing temperatures. Aggregate used in asphalt concrete should
meet particular gradations. Material meeting CDOT Grading S or SX specifications or equivalent
is recommended for asphalt concrete. Mix designs should be submitted prior to construction to
verify their adequacy. Asphalt material should be placed in maximum 3-inch lifts and compacted
within a range of 92 to 96 percent of the theoretical maximum (Rice) density (ASTM D2041).
Where rigid pavements are used, the concrete should be produced from an approved mix design
with the following minimum properties:
Properties Value
Compressive strength 4,000 psi
Cement type Type I or II portland cement
Entrained air content (%) 5 to 8
Concrete aggregate ASTM C33 and CDOT section 703
Concrete should be deposited by truck mixers or agitators and placed a maximum of 90 minutes
from the time the water is added to the mix. Longitudinal and transverse joints should be provided
as needed in concrete pavements for expansion/contraction and isolation per ACI 325. The
location and extent of joints should be based upon the final pavement geometry.
Proper joint spacing will also be required for PCC pavements to prevent excessive slab curling
and shrinkage cracking. All joints should be sealed to prevent entry of foreign material and
dowelled where necessary for load transfer.
For areas subject to concentrated and repetitive loading conditions (if any) such as dumpster
pads, truck delivery docks and ingress/egress aprons, we recommend using a portland cement
concrete pavement with a thickness of at least 6 inches underlain by at least 4 inches of granular
base. Prior to placement of the granular base, the areas should be thoroughly proofrolled. For
dumpster pads, the concrete pavement area should be large enough to support the container and
tipping axle of the refuse truck.
Pavement performance is affected by its surroundings. In addition to providing preventive
maintenance, the civil engineer should consider the following recommendations in the design and
layout of pavements:
n Site grades should slope a minimum of 2 percent away from the pavements;
n The subgrade and the pavement surface have a minimum 2 percent slope to promote proper
surface drainage;
n Consider appropriate edge drainage and pavement under drain systems;
n Install pavement drainage surrounding areas anticipated for frequent wetting;
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n Install joint sealant and seal cracks immediately;
n Seal all landscaped areas in, or adjacent to pavements to reduce moisture migration to
subgrade soils; and
n Placing compacted, low permeability backfill against the exterior side of curb and gutter.
4.3.3 Pavements – Construction Considerations
Openings in pavement, such as landscape islands, are sources for water infiltration into
surrounding pavements. Water collects in the islands and migrates into the surrounding subgrade
soils thereby degrading support of the pavement. This is especially applicable for islands with
raised concrete curbs, irrigated foliage, and low permeability near-surface soils. The civil design
for the pavements with these conditions should include features to restrict or to collect and
discharge excess water from the islands. Examples of features are edge drains connected to the
storm water collection system or other suitable outlet and impermeable barriers preventing lateral
migration of water such as a cutoff wall installed to a depth below the pavement structure.
4.3.4 Pavements – Maintenance
Preventative maintenance should be planned and provided for an ongoing pavement
management program in order to enhance future pavement performance. Preventive
maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching)
and global maintenance (e.g. surface sealing). Preventative maintenance is usually the first
priority when implementing a planned pavement maintenance program and provides the highest
return on investment for pavements.
5.0 GENERAL COMMENTS
Terracon should be retained to review the final design plans and specifications so comments can
be made regarding interpretation and implementation of our geotechnical recommendations in
the design and specifications. Terracon also should be retained to provide observation and testing
services during grading, excavation, foundation construction and other earth-related construction
phases of the project.
The analysis and recommendations presented in this report are based upon the data obtained
from the borings performed at the indicated locations and from other information discussed in this
report. This report does not reflect variations that may occur between borings, across the site, or
due to the modifying effects of construction or weather. The nature and extent of such variations
may not become evident until during or after construction. If variations appear, we should be
immediately notified so that further evaluation and supplemental recommendations can be
provided.
The scope of services for this project does not include either specifically or by implication any
environmental or biological (e.g., mold, fungi, and bacteria) assessment of the site or identification
or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about
the potential for such contamination or pollution, other studies should be undertaken.
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
Responsive ■ Resourceful ■ Reliable 25
This report has been prepared for the exclusive use of our client for specific application to the
project discussed and has been prepared in accordance with generally accepted geotechnical
engineering practices. No warranties, either express or implied, are intended or made. Site
safety, excavation support, and dewatering requirements are the responsibility of others. In the
event that changes in the nature, design, or location of the project as described in this report are
planned, the conclusions and recommendations contained in this report shall not be considered
valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this
report in writing.
APPENDIX A
FIELD EXPLORATION
TOPOGRAPHIC MAP IMAGE COURTESY OF
THE U.S. GEOLOGICAL SURVEY
QUADRANGLES INCLUDE: HORSETOOTH
RESERVOIR, CO (1975) and FORT COLLINS,
CO (1984).
SITE LOCATION MAP
Standard at Fort Collins
Northeast of West Prospect Road and Sheely Drive
Fort Collins, CO
1901 Sharp Point Dr Ste C
Fort Collins, CO 80525-4429
20165058
DIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
KFS
EDB
EDB
EDB
7/28/16
Project No.
File Name:
Date:
A-1
Exhibit
SITE
1”=2,000’
Scale:
LEGEND
1 Approximate boring location (Boring elevation
referenced to BM 19-97 at the southeast corner of
West Elizabeth and South Shields Street; Elevation
5025.74, NAVD88)
Approximate location of resistivity survey
EXPLORATION PLAN
1901 Sharp Point Dr Ste C
Fort Collins, CO 80525-4429
20165058
AERIAL PHOTOGRAPHY PROVIDED BY
MICROSOFT BING MAPS
Pressuremeter Test
Standard at Fort Collins
Northeast of West Prospect Road and Sheely Drive
Fort Collins, CO
DIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
KFS
EDB
EDB
EDB
7/28/16
Scale:
Project No.
File Name:
Date:
AS SHOWN A-2
Exhibit
Pressuremeter Test
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
Responsive ■ Resourceful ■ Reliable Exhibit A-3
Field Exploration Description
The locations of borings were based upon the proposed development shown on a provided site
plan as well reasonably accessible locations for our truck-mounted drill rig. The borings were
located in the field by measuring from existing site features. The ground surface elevation was
surveyed at each boring location referencing the City of Fort Collins’ benchmark 19-97 at the
southeast corner of West Elizabeth Street and South Shields Street using an engineer’s level.
The borings were drilled with a CME-550 truck-mounted rotary drill rig with solid-stem augers,
hollow-stem augers, and NX rock core. During the drilling operations, lithologic logs were
recorded for each the boring by the field engineer. Disturbed samples were obtained at selected
intervals utilizing a 2-inch outside diameter split-spoon sampler and a 3-inch outside diameter
ring-barrel sampler. NX core was collected and stored in core boxes. Penetration resistance
values were recorded in a manner similar to the standard penetration test (SPT). This test consists
of driving the sampler into the ground with a 140-pound hammer free-falling through a distance
of 30 inches. The number of blows required to advance the ring-barrel sampler 12 inches (18
inches for standard split-spoon samplers, final 12 inches are recorded) or the interval indicated,
is recorded as a standard penetration resistance value (N-value). The blow count values are
indicated on the boring logs at the respective sample depths. Ring-barrel sample blow counts are
not considered N-values.
A CME automatic SPT hammer was used to advance the samplers in the borings performed on this
site. A greater efficiency is typically achieved with the automatic hammer compared to the
conventional safety hammer operated with a cathead and rope. Published correlations between the
SPT values and soil properties are based on the lower efficiency cathead and rope method. This
higher efficiency affects the standard penetration resistance blow count value by increasing the
penetration per hammer blow over what would be obtained using the cathead and rope method. The
effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of
the subsurface information for this report.
The standard penetration test provides a reasonable indication of the in-place density of sandy
type materials, but only provides an indication of the relative stiffness of cohesive materials since
the blow count in these soils may be affected by the moisture content of the soil. In addition,
considerable care should be exercised in interpreting the N-values in gravelly soils, particularly
where the size of the gravel particle exceeds the inside diameter of the sampler.
Groundwater measurements were obtained in the borings at the time of site exploration and
several days after drilling. After subsequent groundwater measurements were obtained, the
borings were backfilled with auger cuttings and sand (if needed) and patched (if needed). Some
settlement of the backfill and/or patch may occur and should be repaired as soon as possible.
In addition to soil borings, surface seismic testing was performed (Exhibit A-2). Terracon utilized
the SeisOpt®ReMi™ method to develop the full-depth (100 feet) shear wave profile at the site for
use in determining the seismic site class as described in the 2009/2012 International Building Code
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
Responsive ■ Resourceful ■ Reliable Exhibit A-4
(IBC). This method employs non-linear optimization technology to derive one-dimensional S-wave
velocities from refraction microtremor (ambient noise) recordings using a seismograph and low
frequency, refraction geophones. We performed a single ReMi survey (array) across the site due to
access constraints. We utilized 12 receivers (geophones) set along a relatively straight-line array
with a 15±foot receiver spacing for a 300±foot long transverse. A number of unfiltered, 30 second
records were collected using the background noise (traffic).
The collected data, the response spectrum in the 5 to 40 Hz range, was processed using computer
software (SeisOpt® ReMi™ by Optim, LLC) with the results plotted as a conventional shear wave
vs. depth profile. The shear wave dispersion curve and the selected point plot of the data is included
as Exhibit A-11 in this appendix.
Pressuremeter testing was performed at two (2) locations (Boring Nos. 4 and 5, Exhibit A-2).
Three (3) tests were performed at Boring No. 4 and two (2) tests were performed at Boring No. 5
at varying depths within the bedrock strata. Pressuremeter testing was performed using a
cylindrical probe with an inner rubber membrane and an outer protective sheath that were inflated
using fluid, against the sidewalls of the borings at predetermined depths. The deformation of the
bearing strata was measured periodically while increasing pressures until the bedrock failed in
shear.
Using the data collected during pressuremeter testing, in-situ strength parameters were obtained
including Young’s Moduli, limit pressures, and Menard deformation moduli. Using these values,
the soil and bedrock was modeled more accurately than conventional methods, and values for
deep foundation design and construction criteria were calculated. Pressuremeter test results are
included in this Appendix of this report.
37
11
32
13
18
22
30
33
20
15
109
92
23-13-10
5022.5+/-
5017.5+/-
5007.5+/-
5002.5+/-
4981+/-
4962.5+/-
-2.5/1,000
4-4-5
N=9
5-7
3-3-3
N=6
2-3-5
N=8
3-3-4
N=7
3-4-7
4-6
3-5-5
N=10
8-12-16
N=28
10-21
50/5"
0.5
5.5
15.5
20.5
42.0
60.4
ASPHALT: 5.5 inches
FILL: Clayey Sand, fine to coarse grained,
reddish-brown to brown red
CLAYEY SAND (SC), fine to coarse
grained, brown to reddish-brown, loose
WELL GRADED SAND, fine to coarse
grained, reddish-brown to yellowish-brown,
loose
LEAN CLAY WITH SAND, reddish-brown,
medium stiff to stiff
no recovery
INTERBEDDED SANDSTONE and
CLAYSTONE, grayish-brown to
greenish-brown, laminated bedding,
weathered to very hard, iron oxides
Boring Terminated at 60.4 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
31
9
9
7
22
13
23
26
13
101
24-15-9
NP
5023
5018
5009.5
5004.5
4999.5
4993
4988.5
3-3-4
N=7
2-2-2
N=4
4-3-2
N=5
6-5-5
N=10
7-8
3-3-5
N=8
9-15-15
N=30
10-11
0.5
5.5
14.0
19.0
24.0
30.5
35.0
ASPHALT: 4.5 inches
FILL: Clayey Sand, fine to coarse grained,
reddish-brown to brown red
CLAYEY SAND, fine to coarse grained,
brown to reddish-brown, loose
POORLY GRADED SAND WITH SILT
AND GRAVEL, fine to medium grained,
reddish-brown to yellowish-brown, medium
dense
SANDY LEAN CLAY/CLAYEY SAND, fine
to medium grained, yellowish-brown,
stiff/medium dense
POORLY GRADED SAND WITH SILT
AND GRAVEL (SP-SM), brown to light
brown, loose
WELL GRADED SAND WITH GRAVEL,
fine to coarse grained, reddish-brown,
medium dense to dense
no recovery
Boring Terminated at 35 Feet
7
11
18
20
23
28
18
117
107
5021
5016
5012.5
4996
4987.5
4986
0.0/1,000
5-6-8
N=14
10-11
2-4-4
N=8
5-7
3-3-2
N=5
3-3-5
N=8
4-7-8
N=15
4-3-5
N=8
0.5
5.5
9.0
25.5
34.0
35.5
ASPHALT: 6 inches
FILL: Clayey Sand, fine to coarse grained,
reddish-brown to brown red
CLAYEY SAND, fine to coarse grained,
light brown to reddish-brown, loose
LEAN CLAY WITH SAND, fine to coarse
grained, reddish-brown to yellowish-brown,
medium stiff to stiff
POORLY GRADED SAND WITH SILT
AND GRAVEL, reddish-brown, medium
dense
LEAN CLAY WITH SAND, reddish-brown,
stiff, no recovery
Boring Terminated at 35.5 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4-inch solid-stem auger
Abandonment Method:
58
50
82
78
49
70
15
10
18
14
19
23
25
17
17
27-19-8
31-14-17
5022
5017
5003.5
4993.5
4988.5
4964
96
100
100
100
3-5-6
N=11
4-7-8
N=15
3-5-5
N=10
3-4-4
N=8
4-5-7
N=12
2-2-3
N=5
4-10-7
N=17
10-17-21
N=38
17-28-32
N=60
0.3
5.5
19.0
29.0
34.0
58.5
ASPHALT: 4 inches
FILL: Clayey Sand (SC), fine to coarse
grained, reddish-brown to brown red
LEAN CLAY WITH SAND (CL), brown to
reddish-brown, medium stiff to stiff
WELL GRADED SAND WITH CLAY AND
GRAVEL, fine to coarse grained,
reddish-brown to yellowish-brown, loose to
medium dense
62
96
94
85
75
18
10
20
12
25
25
21
24
24
22
31-18-13
41-17-24
5014
5009
4990
4975.5
4961
87
100
100
3-5-6
N=11
4-7-8
N=15
9-5-4
N=9
4-5-4
N=9
3-4-4
N=8
3-3-3
N=6
3-4-5
N=9
5-5-8
N=13
3-5-5
N=10
3-4-9
N=13
20-21-23
N=44
10.5
15.5
34.5
49.0
63.5
CLAYEY SAND, brown to reddish-brown,
loose to medium dense
POORLY GRADED SAND WITH CLAY,
fine to coarse grained, reddish-brown to
yellowish-brown, loose
LEAN CLAY WITH SAND (CL),
reddish-brown, medium stiff to stiff
WETHERED BEDROCK: Completely to
91
87
93
9
9
16
18
8
22
23
113
34-17-17
22-16-6
47-17-30
5023.5
5013
5008
5002
4996.5
4991.5
-0.2/1,000
5-6-6
N=12
6-6-6
N=12
8-12
4-6-9
N=15
19-24
5-4-3
N=7
5-6-8
N=14
3-7-13
N=20
3.5
14.0
19.0
25.0
30.5
35.5
LEAN CLAY WITH SAND, reddish-brown,
stiff
CLAYEY SAND, fine to medium grained,
reddish-brown to brown red, medium dense
LEAN CLAY (CL), brown to
reddish-brown, stiff
SILTY CLAY (CL-ML), reddish-brown to
yellowish-brown, very stiff
LEAN CLAY (CL), yellowish-brown,
medium stiff to hard
WEATHERED BEDROCK: LEAN CLAY
WITH SAND, brown to greenish-brown,
stiff to very stiff (weathered)
Boring Terminated at 35.5 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
3073 38
51
9
9
15
13
29
27
20
25
19
15
14
101
102 45-17-28
30-16-14
5021
5015.5
5004.5
5000.5
4997.5
4995.5
4987
4965
-0.5/1000
-1.4/1000
4-4-5
N=9
4-6-5
N=11
3-4-5
N=9
3-3-5
N=8
2-3-4
N=7
3-4
3-5-6
N=11
6-9
10-10-16
N=26
31
50/5"
50/5"
3.5
9.0
20.0
24.0
27.0
29.0
37.5
59.4
LEAN CLAY WITH SAND, reddish-brown,
medium stiff
CLAYEY SAND, fine to coarse grained,
reddish-brown to brown red, medium dense
LEAN CLAY WITH SAND, reddish-brown
to brown red, medium stiff to stiff,
micaceous, increasing sand content with
15080 A Circle Omaha, Nebraska 68144
PH. (402) 330-2202 FAX. (402) 330-7606
A-12
ProjectProfile Manager: Shear Wave EXHIBIT #
Drawn by:
Checked by:
Approved by:
RMK
Project No.
Scale:
File Name:
Date:
20165058
N.T.S.
NS.xlsx
JULY 2016
North-South ReMi Profile
CMW
EDB
EDB
Standard at Fort Collins
NE of West Prospect Road and Sheely Drive
Fort Collins, Colorado
Average Shear Wave Velocity to 100 ft (rounded) = 1,150 ft/s
No
44.00 ft
3.28 ft
0.33
Probe size: 1.000
Pressure Volume Pressure Volume DR/R0
psi in³ psi in³ %
0 0.0 20 0.0 0.00 8,715 psi
58 32.6 75 32.4 14.00
116 37.9 132 37.3 15.99 ◄ 690 psi
174 41.3 190 40.4 17.21
232 43.7 248 42.5 18.06 12.62
290 46.7 306 45.2 19.11 ◄
348 50.1 364 48.4 20.32 306 psi
392 54.3 407 52.3 21.85
#N/A #N/A #N/A #N/A #N/A #N/A 2.26
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Raw Readings
Project name:
Borehole name:
Test number:
Test date: (mm/dd/yyyy)
TEXAM Pressuremeter Test
Test depth:
Manometer height above ground:
Standard at Fort. Collins
B-4
7/12/2016
Use of a slotted casing:
PRESSIO COMPANION V.15
Ratio E / PL
:
Yield pressure PF
:
Ratio PL
/ PF
:
Calibration Sheet Reference
2
Remarks
Ultimate pressure PL
:
1
N Fluid density:
Corrected Readings
No
50.00 ft
3.28 ft
0.33
Probe size: 1.000
Pressure Volume Pressure Volume DR/R0
psi in³ psi in³ %
0 0.0 23 0.0 0.00 16,371 psi
58 28.1 77 27.8 12.15
116 31.1 135 30.5 13.23 856 psi
174 32.8 193 31.9 13.81 ◄
232 34.2 251 33.0 14.26 19.13
290 35.9 309 34.5 14.86
348 37.7 367 35.9 15.43 ◄ 367 psi
406 40.0 425 37.9 16.24
450 42.7 468 40.5 17.24 2.33
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Raw Readings
Project name:
Borehole name:
Test number:
Test date: (mm/dd/yyyy)
TEXAM Pressuremeter Test
Test depth:
Manometer height above ground:
Standard at Fort Collins
B-4
7/12/2016
Use of a slotted casing:
PRESSIO COMPANION V.15
Ratio E / PL
:
Yield pressure PF
:
Ratio PL
/ PF
:
Calibration Sheet Reference
2
Remarks
Ultimate pressure PL
:
2
N Fluid density:
Corrected Readings
No
60.00 ft
3.28 ft
0.33
Probe size: 1.000
Pressure Volume Pressure Volume DR/R0
psi in³ psi in³ %
0 0.0 27 0.0 0.00 40,534 psi
44 25.4 67 25.2 11.04
87 27.0 111 26.5 11.61 2,155 psi
131 28.4 154 27.7 12.10
174 29.2 198 28.3 12.34 18.81
218 29.8 241 28.7 12.52 ◄
261 30.6 285 29.3 12.74 763 psi
305 31.9 328 30.3 13.17
348 32.3 372 30.6 13.28 2.83
392 32.8 415 30.9 13.39
435 33.4 459 31.2 13.53
479 33.9 502 31.5 13.66
522 34.4 545 31.8 13.77
566 35.0 589 32.1 13.91
609 35.4 632 32.3 13.99
653 36.0 676 32.7 14.15
696 36.6 719 33.1 14.31
740 37.2 763 33.5 14.47 ◄
783 37.8 806 33.8 14.60
827 38.6 850 34.4 14.83
870 39.2 893 34.8 14.99
914 40.0 937 35.4 15.22
957 40.9 980 36.1 15.50
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Ultimate pressure PL
:
3
N Fluid density:
Corrected Readings
Poisson's coefficient:
Pressiometric modulus E:
Test Results
PRESSIO COMPANION V.15
Ratio E / PL
:
Yield pressure PF
:
Ratio PL
/ PF
:
Calibration Sheet Reference
2
Remarks
TEXAM Pressuremeter Test
Test depth:
Manometer height above ground:
Standard at Fort Collins
B-4
7/12/2016
Use of a slotted casing:
Raw Readings
Project name:
No
50.00 ft
3.28 ft
0.33
Probe size: 1.000
Pressure Volume Pressure Volume DR/R0
psi in³ psi in³ %
0 0.0 23 0.0 0.00 15,488 psi
58 23.2 78 22.9 10.09
116 26.2 136 25.7 11.25 ◄ 769 psi
174 27.9 193 27.1 11.83
232 29.3 251 28.1 12.27 20.15
290 31.1 309 29.7 12.90
348 32.8 367 31.1 13.48 ◄ 367 psi
406 35.6 425 33.5 14.48
464 41.0 483 38.7 16.54 2.09
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
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#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Raw Readings
Project name:
Borehole name:
Test number:
Test date: (mm/dd/yyyy)
TEXAM Pressuremeter Test
Test depth:
Manometer height above ground:
Standard at Fort Collins
B-5
7/12/2016
Use of a slotted casing:
PRESSIO COMPANION V.15
Ratio E / PL
:
Yield pressure PF
:
Ratio PL
/ PF
:
Calibration Sheet Reference
3
Remarks
Ultimate pressure PL
:
5
N Fluid density:
Corrected Readings
No
60.00 ft
3.28 ft
0.33
Probe size: 1.000
Pressure Volume Pressure Volume DR/R0
psi in³ psi in³ %
0 0.0 27 0.0 0.00 25,600 psi
73 23.2 97 22.8 10.06
145 25.7 169 25.0 10.96 1,950 psi
218 27.0 241 25.9 11.36 ◄
290 28.4 314 27.0 11.79 13.13
363 29.8 386 28.0 12.22
435 31.1 459 28.9 12.60 604 psi
508 32.5 531 29.9 13.00
580 34.0 604 31.1 13.48 ◄ 3.23
653 35.8 676 32.5 14.08
725 37.8 748 34.2 14.74
798 40.3 821 36.3 15.58
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Ultimate pressure PL
:
4
N Fluid density:
Corrected Readings
Poisson's coefficient:
Pressiometric modulus E:
Test Results
PRESSIO COMPANION V.15
Ratio E / PL
:
Yield pressure PF
:
Ratio PL
/ PF
:
Calibration Sheet Reference
3
Remarks
TEXAM Pressuremeter Test
Test depth:
Manometer height above ground:
Standard at Fort Collins
B-5
7/12/2016
Use of a slotted casing:
Raw Readings
Project name:
APPENDIX B
LABORATORY TESTING
Geotechnical Engineering Report
Standard at Fort Collins ■ Fort Collins, Colorado
September 8, 2016 ■ Terracon Project No. 20165058
Responsive ■ Resourceful ■ Reliable Exhibit B-1
Laboratory Testing Description
The soil and bedrock samples retrieved during the field exploration were returned to the laboratory
for observation by the project geotechnical engineer. At that time, the field descriptions were
reviewed and an applicable laboratory testing program was formulated to determine engineering
properties of the subsurface materials.
Laboratory tests were conducted on selected soil and bedrock samples. The results of these
tests are presented on the boring logs and in this appendix. The test results were used for the
geotechnical engineering analyses, and the development of foundation and earthwork
recommendations. The laboratory tests were performed in general accordance with applicable
locally accepted standards. Soil samples were classified in general accordance with the Unified
Soil Classification System described in Appendix C. Rock samples were visually classified in
general accordance with the description of rock properties presented in Appendix C. Procedural
standards noted in this report are for reference to methodology in general. In some cases variations
to methods are applied as a result of local practice or professional judgment.
n Water content n Plasticity index
n Grain-size distribution
n Consolidation/swell
n Compressive strength
n Water-soluble sulfate content
n Dry density
n pH
n Resistivity
0
10
20
30
40
50
60
0 20 40 60 80 100
CL or OL CH or OH
ML or OL
MH or OH
Boring ID Depth PL PI Description
CLAYEY SAND
CLAYEY SAND
POORLY GRADED SAND with SILT and GRAVEL
CLAYEY SAND
LEAN CLAY with SAND
LEAN CLAY
LEAN CLAY with SAND
LEAN CLAY
SILTY CLAY
LEAN CLAY
CLAYEY SAND
SANDY LEAN CLAY
SC
SC
SP-SM
SC
CL
CL
CL
CL
CL-ML
CL
SC
CL
Fines
P
L
A
S
T
I
C
I
T
Y
I
N
D
E
X
LIQUID LIMIT
"U" Line
"A" Line
23
24
NP
27
31
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
100 10 1 0.1 0.01 0.001
1
2
2
4
4
23
24
NP
27
31
0.3
0.261
0.595
1.108
0.127
19
25
25
25
19
6 16
20 30
40 50
1.5 6 200
810
6.9
13.1
15.5
12.1
2.4
0.082
14
37.0
30.6
9.3
48.7
70.3
%Fines
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
100 10 1 0.1 0.01 0.001
5
5
6
6
6
31
41
34
22
47
4.75
9.5
2
4.75
4.75
6 16
20 30
40 50
1.5 6 200
810
0.0
0.3
0.0
0.0
0.0
14
85.1
75.2
91.5
87.1
93.2
%Fines
LL PL PI
1 4
3/4 1/2
60
fine
5
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
100 10 1 0.1 0.01 0.001
7
7
45
30
0.241
0.094
19
4.75
6 16
20 30
40 50
1.5 6 200
810
12.2
0.0
14
37.6
50.9
%Fines
LL PL PI
1 4
3/4 1/2
60
fine
7
7
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
coarse fine
U.HYDROMETERS. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
17
16
28
14
D100
Cc Cu
SILT OR CLAY
4
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited 2.5 percent compression at an applied load of 1,000 psf.
1901 Sharp Point Dr Ste C
Fort Collins, CO
PROJECT: Standard at Fort Collins PROJECT NUMBER: 20165058
SITE: Northeast of West Prospect
Road and Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate
Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-6
Specimen Identification Classification , pcf
109 32
WC, %
1 9 - 10 ft LEAN CLAY with SAND
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. 65155045-SWELL/CONSOL 20165058.GPJ TERRACON2012.GDT 7/28/16
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited no movement at an applied load of 1,000 psf.
1901 Sharp Point Dr Ste C
Fort Collins, CO
PROJECT: Standard at Fort Collins PROJECT NUMBER: 20165058
SITE: Northeast of West Prospect
Road and Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate
Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-7
Specimen Identification Classification , pcf
107 20
WC, %
3 14 - 15.5 ft LEAN CLAY with SAND
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. 65155045-SWELL/CONSOL 20165058.GPJ TERRACON2012.GDT 7/28/16
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibit 0.2 percent compression at an applied load of 1,000 psf.
1901 Sharp Point Dr Ste C
Fort Collins, CO
PROJECT: Standard at Fort Collins PROJECT NUMBER: 20165058
SITE: Northeast of West Prospect
Road and Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate
Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-8
Specimen Identification Classification , pcf
113 16
WC, %
6 9 - 10 ft SANDY CLAY/CLAYEY SAND
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. 65155045-SWELL/CONSOL 20165058.GPJ TERRACON2012.GDT 7/28/16
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited 0.5 percent compression at an applied load of 1,000 psf.
1901 Sharp Point Dr Ste C
Fort Collins, CO
PROJECT: Standard at Fort Collins PROJECT NUMBER: 20165058
SITE: Northeast of West Prospect
Road and Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate
Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-9
Specimen Identification Classification , pcf
101 27
WC, %
7 24 - 25 ft LEAN CLAY with SAND
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. 65155045-SWELL/CONSOL 20165058.GPJ TERRACON2012.GDT 7/28/16
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited 1.4 percent compression at an applied load of 1,000 psf.
1901 Sharp Point Dr Ste C
Fort Collins, CO
PROJECT: Standard at Fort Collins PROJECT NUMBER: 20165058
SITE: Northeast of West Prospect
Road and Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate
Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-10
Specimen Identification Classification , pcf
103 23
WC, %
7 34 - 35 ft LEAN CLAY with SAND
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. 65155045-SWELL/CONSOL 20165058.GPJ TERRACON2012.GDT 7/28/16
0
500
1,000
1,500
2,000
2,500
3,000
3,500
0 2 4 6 8 10 12 14 16
2.39
5.63
3073
Assumed Specific Gravity:
45 17 28
Unconfined Compressive Strength (psf)
Undrained Shear Strength: (psf)
Calculated Void Ratio:
Height / Diameter Ratio:
SPECIMEN FAILURE MODE SPECIMEN TEST DATA
2.36
15.00
Moisture Content: %
Dry Density: pcf
COMPRESSIVE STRESS - psf
DESCRIPTION: LEAN CLAY with SAND
25
1536
LL PL PI Percent < #200 Sieve
38
AXIAL STRAIN - %
Remarks:
ASTM D2166
UNCONFINED COMPRESSION TEST
Failure Mode: Bulge (dashed)
Diameter: in.
Height: in.
Calculated Saturation: %
Failure Strain: %
Strain Rate: in/min
102
SAMPLE TYPE: D&M RING SAMPLE LOCATION: 7 @ 34 - 35 feet
PROJECT NUMBER: 20165058
PROJECT: Standard at Fort Collins
SITE: Northeast of West Prospect Road and
Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-11
1901 Sharp Point Dr Ste C
Fort Collins, CO
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. UNCONFINED 20165058.GPJ TERRACON2012.GDT 7/28/16
TASK NO: 160720033
Analytical Results
Terracon, Inc. - Fort Collins
Eric D. Bernhardt
Company:
Report To:
Company:
Bill To:
1901 Sharp Point Drive
Suite C
Fort Collins CO 80525
Accounts Payable
Terracon, Inc. - A/P
18001 W. 106th St
Suite 300
Olathe KS 66061
Standard at Fort Collins 20165058
Date Reported: 8/2/16
Task No.: 160720033
Matrix: Soil - Geotech
Date Received: 7/20/16
Client Project:
Client PO:
Customer Sample ID 20165058 B1 @ 24 Ft.
Test Method
Lab Number: 160720033-01
Result
Chloride - Water Soluble 0.0015 % AASHTO T291-91/ ASTM D4327
pH 8.0 units AASHTO T289-91
Redox Potential 302 mv ASTM D1498
Resistivity 1372 ohm.cm AASHTO T288-91
Sulfate - Water Soluble 0.007 % AASHTO T290-91/ ASTM D4327
Sulfide NegativeC105 AWWA
Customer Sample ID 20165058 B3 @ 9 Ft.
Test Method
Lab Number: 160720033-02
Result
Chloride - Water Soluble 0.0060 % AASHTO T291-91/ ASTM D4327
pH 8.0 units AASHTO T289-91
Redox Potential 282 mv ASTM D1498
Resistivity 1437 ohm.cm AASHTO T288-91
Sulfate - Water Soluble 0.005 % AASHTO T290-91/ ASTM D4327
Sulfide NegativeC105 AWWA
240 South Main Street / Brighton, CO 80601-0507 / 303-659-2313
Mailing Address: P.O. Box 507 / Brighton, CO 80601-0507 / Fax: 303-659-2315
DATA APPROVED FOR RELEASE BY
Abbreviations/ References:
160720033
AASHTO - American Association of State Highway and Transportation Officials.
ASTM - American Society for Testing and Materials.
ASA - American Society of Agronomy.
DIPRA - Ductile Iron Pipe Research Association Handbook of Ductile Iron Pipe.
TASK NO: 160720033
Analytical Results
Terracon, Inc. - Fort Collins
Eric D. Bernhardt
Company:
Report To:
Company:
Bill To:
1901 Sharp Point Drive
Suite C
Fort Collins CO 80525
Accounts Payable
Terracon, Inc. - A/P
18001 W. 106th St
Suite 300
Olathe KS 66061
Standard at Fort Collins 20165058
Date Reported: 8/2/16
Task No.: 160720033
Matrix: Soil - Geotech
Date Received: 7/20/16
Client Project:
Client PO:
Customer Sample ID 20165058 B7 @ 49 Ft.
Test Method
Lab Number: 160720033-03
Result
Chloride - Water Soluble 0.0009 % AASHTO T291-91/ ASTM D4327
pH 8.0 units AASHTO T289-91
Redox Potential 269 mv ASTM D1498
Resistivity 975 ohm.cm AASHTO T288-91
Sulfate - Water Soluble 0.034 % AASHTO T290-91/ ASTM D4327
Sulfide NegativeC105 AWWA
240 South Main Street / Brighton, CO 80601-0507 / 303-659-2313
Mailing Address: P.O. Box 507 / Brighton, CO 80601-0507 / Fax: 303-659-2315
DATA APPROVED FOR RELEASE BY
Abbreviations/ References:
160720033
AASHTO - American Association of State Highway and Transportation Officials.
ASTM - American Society for Testing and Materials.
ASA - American Society of Agronomy.
DIPRA - Ductile Iron Pipe Research Association Handbook of Ductile Iron Pipe.
APPENDIX C
SUPPORTING DOCUMENTS
Exhibit: C-1
1,000 to 2,000
4,000 to 8,000
Unconfined
Compressive
Strength
Qu, (psf)
500 to 1,000
2,000 to 4,000
> 8,000
less than 500
Non-plastic
Low
Medium
High
DESCRIPTION OF SYMBOLS AND ABBREVIATIONS
SAMPLING
WATER LEVEL
FIELD TESTS
GENERAL NOTES
Over 12 in. (300 mm)
12 in. to 3 in. (300mm to 75mm)
3 in. to #4 sieve (75mm to 4.75 mm)
#4 to #200 sieve (4.75mm to 0.075mm
Passing #200 sieve (0.075mm)
Particle Size
< 5
5 - 12
> 12
Percent of
Dry Weight
Descriptive Term(s)
of other constituents
RELATIVE PROPORTIONS OF FINES
0
1 - 10
11 - 30
> 30
Plasticity Index
Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry
weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have
less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and
silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be
added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined
on the basis of their in-place relative density and fine-grained soils on the basis of their consistency.
LOCATION AND ELEVATION NOTES
Percent of
Dry Weight
Major Component
of Sample
Trace
With
Modifier
RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY
Trace
With
Modifier
DESCRIPTIVE SOIL CLASSIFICATION
Boulders
Cobbles
UNIFIED SOIL CLASSIFICATION SYSTEM
Exhibit C-2
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A
Soil Classification
Group
Symbol Group Name B
Coarse Grained Soils:
More than 50% retained
on No. 200 sieve
Gravels:
More than 50% of
coarse fraction retained
on No. 4 sieve
Clean Gravels:
Less than 5% fines C
Cu 4 and 1 Cc 3 E GW Well-graded gravel F
Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F
Gravels with Fines:
More than 12% fines C
Fines classify as ML or MH GM Silty gravel F,G,H
Fines classify as CL or CH GC Clayey gravel F,G,H
Sands:
50% or more of coarse
fraction passes No. 4
sieve
Clean Sands:
Less than 5% fines D
Cu 6 and 1 Cc 3 E SW Well-graded sand I
Cu 6 and/or 1 Cc 3 E SP Poorly graded sand I
Sands with Fines:
More than 12% fines D
Fines classify as ML or MH SM Silty sand G,H,I
Fines classify as CL or CH SC Clayey sand G,H,I
Fine-Grained Soils:
50% or more passes the
No. 200 sieve
Silts and Clays:
Liquid limit less than 50
Inorganic:
PI 7 and plots on or above “A” line J CL Lean clay K,L,M
PI 4 or plots below “A” line J ML Silt K,L,M
Organic:
Liquid limit - oven dried
0.75 OL
Organic clay K,L,M,N
Liquid limit - not dried Organic silt K,L,M,O
Silts and Clays:
Liquid limit 50 or more
Inorganic:
PI plots on or above “A” line CH Fat clay K,L,M
PI plots below “A” line MH Elastic Silt K,L,M
Organic:
Liquid limit - oven dried
0.75 OH
Organic clay K,L,M,P
Liquid limit - not dried Organic silt K,L,M,Q
Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat
A Based on the material passing the 3-inch (75-mm) sieve
B If field sample contained cobbles or boulders, or both, add “with cobbles
or boulders, or both” to group name.
DESCRIPTION OF ROCK PROPERTIES
Exhibit C-3
WEATHERING
Fresh Rock fresh, crystals bright, few joints may show slight staining. Rock rings under hammer if crystalline.
Very slight Rock generally fresh, joints stained, some joints may show thin clay coatings, crystals in broken face show
bright. Rock rings under hammer if crystalline.
Slight Rock generally fresh, joints stained, and discoloration extends into rock up to 1 in. Joints may contain clay. In
granitoid rocks some occasional feldspar crystals are dull and discolored. Crystalline rocks ring under hammer.
Moderate Significant portions of rock show discoloration and weathering effects. In granitoid rocks, most feldspars are dull
and discolored; some show clayey. Rock has dull sound under hammer and shows significant loss of strength
as compared with fresh rock.
Moderately severe All rock except quartz discolored or stained. In granitoid rocks, all feldspars dull and discolored and majority
show kaolinization. Rock shows severe loss of strength and can be excavated with geologist’s pick.
Severe All rock except quartz discolored or stained. Rock “fabric” clear and evident, but reduced in strength to strong
soil. In granitoid rocks, all feldspars kaolinized to some extent. Some fragments of strong rock usually left.
Very severe All rock except quartz discolored or stained. Rock “fabric” discernible, but mass effectively reduced to “soil” with
only fragments of strong rock remaining.
Complete Rock reduced to ”soil”. Rock “fabric” not discernible or discernible only in small, scattered locations. Quartz may
be present as dikes or stringers.
HARDNESS (for engineering description of rock – not to be confused with Moh’s scale for minerals)
Very hard Cannot be scratched with knife or sharp pick. Breaking of hand specimens requires several hard blows of
geologist’s pick.
Hard Can be scratched with knife or pick only with difficulty. Hard blow of hammer required to detach hand specimen.
Moderately hard Can be scratched with knife or pick. Gouges or grooves to ¼ in. deep can be excavated by hard blow of point of
a geologist’s pick. Hand specimens can be detached by moderate blow.
Medium Can be grooved or gouged 1/16 in. deep by firm pressure on knife or pick point. Can be excavated in small
chips to pieces about 1-in. maximum size by hard blows of the point of a geologist’s pick.
Soft Can be gouged or grooved readily with knife or pick point. Can be excavated in chips to pieces several inches in
size by moderate blows of a pick point. Small thin pieces can be broken by finger pressure.
Very soft Can be carved with knife. Can be excavated readily with point of pick. Pieces 1-in. or more in thickness can be
broken with finger pressure. Can be scratched readily by fingernail.
Joint, Bedding, and Foliation Spacing in Rock
a
Spacing Joints Bedding/Foliation
Less than 2 in. Very close Very thin
2 in. – 1 ft. Close Thin
1 ft. – 3 ft. Moderately close Medium
3 ft. – 10 ft. Wide Thick
More than 10 ft. Very wide Very thick
a. Spacing refers to the distance normal to the planes, of the described feature, which are parallel to each other or nearly so.
Rock Quality Designator (RQD) a Joint Openness Descriptors
RQD, as a percentage Diagnostic description Openness Descriptor
Exceeding 90 Excellent No Visible Separation Tight
90 – 75 Good Less than 1/32 in. Slightly Open
75 – 50 Fair 1/32 to 1/8 in. Moderately Open
50 – 25 Poor 1/8 to 3/8 in. Open
Less than 25 Very poor 3/8 in. to 0.1 ft. Moderately Wide
a. RQD (given as a percentage) = length of core in pieces Greater than 0.1 ft. Wide
4 in. and longer/length of run.
References: American Society of Civil Engineers. Manuals and Reports on Engineering Practice - No. 56. Subsurface Investigation for
Design and Construction of Foundations of Buildings. New York: American Society of Civil Engineers, 1976. U.S.
Department of the Interior, Bureau of Reclamation, Engineering Geology Field Manual.
Exhibit C-4
LABORATORY TEST
SIGNIFICANCE AND PURPOSE
Test Significance Purpose
California Bearing
Ratio
Used to evaluate the potential strength of subgrade soil,
subbase, and base course material, including recycled
materials for use in road and airfield pavements.
Pavement Thickness
Design
Consolidation
Used to develop an estimate of both the rate and amount of
both differential and total settlement of a structure. Foundation Design
Direct Shear
Used to determine the consolidated drained shear strength
of soil or rock.
Bearing Capacity,
Foundation Design,
and Slope Stability
Dry Density
Used to determine the in-place density of natural, inorganic,
fine-grained soils.
Index Property Soil
Behavior
Expansion
Used to measure the expansive potential of fine-grained soil
and to provide a basis for swell potential classification.
Foundation and Slab
Design
Gradation
Used for the quantitative determination of the distribution of
particle sizes in soil. Soil Classification
Liquid & Plastic Limit,
Plasticity Index
Used as an integral part of engineering classification
systems to characterize the fine-grained fraction of soils, and
to specify the fine-grained fraction of construction materials.
Soil Classification
Permeability
Used to determine the capacity of soil or rock to conduct a
liquid or gas.
Groundwater Flow
Analysis
pH Used to determine the degree of acidity or alkalinity of a soil. Corrosion Potential
Resistivity
Used to indicate the relative ability of a soil medium to carry
electrical currents. Corrosion Potential
R-Value
Used to evaluate the potential strength of subgrade soil,
subbase, and base course material, including recycled
materials for use in road and airfield pavements.
Pavement Thickness
Design
Soluble Sulfate
Used to determine the quantitative amount of soluble
sulfates within a soil mass. Corrosion Potential
Unconfined
Compression
To obtain the approximate compressive strength of soils that
Exhibit C-5
REPORT TERMINOLOGY
(Based on ASTM D653)
Allowable Soil
Bearing Capacity
The recommended maximum contact stress developed at the interface of the foundation
element and the supporting material.
Alluvium
Soil, the constituents of which have been transported in suspension by flowing water and
subsequently deposited by sedimentation.
Aggregate Base
Course
A layer of specified material placed on a subgrade or subbase usually beneath slabs or
pavements.
Backfill A specified material placed and compacted in a confined area.
Bedrock
A natural aggregate of mineral grains connected by strong and permanent cohesive forces.
Usually requires drilling, wedging, blasting or other methods of extraordinary force for
excavation.
Bench A horizontal surface in a sloped deposit.
Caisson (Drilled
Pier or Shaft)
A concrete foundation element cast in a circular excavation which may have an enlarged base.
Sometimes referred to as a cast-in-place pier or drilled shaft.
Coefficient of
Friction
A constant proportionality factor relating normal stress and the corresponding shear stress at
which sliding starts between the two surfaces.
Colluvium
Soil, the constituents of which have been deposited chiefly by gravity such as at the foot of a
slope or cliff.
Compaction The densification of a soil by means of mechanical manipulation
Concrete Slab-on-
Grade
A concrete surface layer cast directly upon a base, subbase or subgrade, and typically used
as a floor system.
Differential
Movement Unequal settlement or heave between, or within foundation elements of structure.
Earth Pressure The pressure exerted by soil on any boundary such as a foundation wall.
ESAL
Equivalent Single Axle Load, a criteria used to convert traffic to a uniform standard, (18,000
pound axle loads).
Engineered Fill
Specified material placed and compacted to specified density and/or moisture conditions
under observations of a representative of a geotechnical engineer.
Equivalent Fluid
A hypothetical fluid having a unit weight such that it will produce a pressure against a lateral
support presumed to be equivalent to that produced by the actual soil. This simplified
approach is valid only when deformation conditions are such that the pressure increases
linearly with depth and the wall friction is neglected.
Existing Fill (or
Man-Made Fill) Materials deposited throughout the action of man prior to exploration of the site.
Existing Grade The ground surface at the time of field exploration.
Exhibit C-6
REPORT TERMINOLOGY
(Based on ASTM D653)
Expansive Potential The potential of a soil to expand (increase in volume) due to absorption of moisture.
Finished Grade The final grade created as a part of the project.
Footing A portion of the foundation of a structure that transmits loads directly to the soil.
Foundation The lower part of a structure that transmits the loads to the soil or bedrock.
Frost Depth The depth at which the ground becomes frozen during the winter season.
Grade Beam
A foundation element or wall, typically constructed of reinforced concrete, used to span between
other foundation elements such as drilled piers.
Groundwater Subsurface water found in the zone of saturation of soils or within fractures in bedrock.
Heave Upward movement.
Lithologic The characteristics which describe the composition and texture of soil and rock by observation.
Native Grade The naturally occurring ground surface.
Native Soil Naturally occurring on-site soil, sometimes referred to as natural soil.
Optimum Moisture
Content
The water content at which a soil can be compacted to a maximum dry unit weight by a given
compactive effort.
Perched Water
Groundwater, usually of limited area maintained above a normal water elevation by the
presence of an intervening relatively impervious continuous stratum.
Scarify To mechanically loosen soil or break down existing soil structure.
Settlement Downward movement.
Skin Friction (Side
Shear)
The frictional resistance developed between soil and an element of the structure such as a
drilled pier.
Soil (Earth)
Sediments or other unconsolidated accumulations of solid particles produced by the physical
and chemical disintegration of rocks, and which may or may not contain organic matter.
Strain The change in length per unit of length in a given direction.
Stress The force per unit area acting within a soil mass.
Strip To remove from present location.
Subbase A layer of specified material in a pavement system between the subgrade and base course.
Subgrade The soil prepared and compacted to support a structure, slab or pavement system.
possess sufficient cohesion to permit testing in the
unconfined state.
Bearing Capacity
Analysis for
Foundations
Water Content
Used to determine the quantitative amount of water in a soil
mass.
Index Property Soil
Behavior
C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded
gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly
graded gravel with silt, GP-GC poorly graded gravel with clay.
D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded
sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded
sand with silt, SP-SC poorly graded sand with clay
E Cu = D60/D10 Cc =
10 60
2
30
D x D
(D )
F If soil contains 15% sand, add “with sand” to group name.
G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.
H If fines are organic, add “with organic fines” to group name.
I If soil contains 15% gravel, add “with gravel” to group name.
J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.
K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,”
whichever is predominant.
L If soil contains 30% plus No. 200 predominantly sand, add “sandy” to
group name.
M If soil contains 30% plus No. 200, predominantly gravel, add
“gravelly” to group name.
N PI 4 and plots on or above “A” line.
O PI 4 or plots below “A” line.
P PI plots on or above “A” line.
Q PI plots below “A” line.
Gravel
Sand
Silt or Clay
Descriptive Term(s)
of other constituents
N
(HP)
(T)
(DCP)
(PID)
(OVA)
< 15
15 - 29
> 30
Term
PLASTICITY DESCRIPTION
Water levels indicated on the soil boring
logs are the levels measured in the
borehole at the times indicated.
Groundwater level variations will occur
over time. In low permeability soils,
accurate determination of groundwater
levels is not possible with short term water
level observations.
Water Level After
a Specified Period of Time
Water Level After a
Specified Period of Time
Water Initially
Encountered
Rock Core
Modified
Dames &
Moore Ring
Sampler
No
Recovery
Standard
Penetration
Test
Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracy
of such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey was
conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic
maps of the area.
Standard Penetration Test
Resistance (Blows/Ft.)
Hand Penetrometer
Torvane
Dynamic Cone Penetrometer
Photo-Ionization Detector
Organic Vapor Analyzer
Very Hard
CONSISTENCY OF FINE-GRAINED SOILS
(More than 50% retained on No. 200 sieve.)
Density determined by
Standard Penetration Resistance
(50% or more passing the No. 200 sieve.)
Consistency determined by laboratory shear strength testing, field
visual-manual procedures or standard penetration resistance
Standard
Penetration or
N-Value
Blows/Ft.
_ 15 - 30
> 30
> 119
< 20
30 - 49
50 - 79
>79
Hard
STRENGTH TERMS
BEDROCK
Loose
Medium Dense
Dense
0 - 3
4 - 9
10 - 29
30 - 50
7 - 18
19 - 58
Very Soft
Soft
Medium-Stiff
Stiff
Very Stiff
Standard
Penetration or
N-Value
Blows/Ft.
2 - 4
4 - 8
8 - 15
< 3
5 - 9
19 - 42
> 42
30 - 49
50 - 89
20 - 29
Medium Hard
Very Dense
RELATIVE DENSITY OF COARSE-GRAINED
SOILS
Descriptive
Term
(Density)
Very Loose
> 50
Ring
Sampler
Blows/Ft.
0 - 6
59 - 98
> 99
Descriptive
Term
(Consistency)
Hard
0 - 1
Ring
Sampler
Blows/Ft.
3 - 4
10 - 18
Ring
Sampler
Blows/Ft.
< 30
90 - 119
Standard
Penetration or
N-Value
Blows/Ft.
Descriptive
Term
(Consistency)
Weathered
Firm
D30 D10 %Gravel %Sand
34 - 35
39 - 40.5
3/8 3 100
3 2 140
COBBLES GRAVEL SAND
USCS Classification
50.2
49.1
D60
coarse medium
Boring ID Depth
Boring ID Depth
GRAIN SIZE DISTRIBUTION
34 - 35
39 - 40.5
CLAYEY SAND (SC)
SANDY LEAN CLAY (CL)
ASTM D422 / ASTM C136
PROJECT NUMBER: 20165058
PROJECT: Standard at Fort Collins
SITE: Northeast of West Prospect Road and
Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-5
1901 Sharp Point Dr Ste C
Fort Collins, CO
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 20165058.GPJ 35159097 - ATTERBERG ISSUE.GPJ 7/26/16
5
6
6
6
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
coarse fine
U.HYDROMETERS. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
18
17
17
16
17
13
24
17
6
30
D100
Cc Cu
SILT OR CLAY
4
D30 D10 %Gravel %Sand
19 - 20.5
34 - 35.5
14 - 15.5
19 - 20
29 - 30.5
3/8 3 100
3 2 140
COBBLES GRAVEL SAND
USCS Classification
14.9
24.6
8.5
12.9
6.8
D60
coarse medium
Boring ID Depth
Boring ID Depth
GRAIN SIZE DISTRIBUTION
19 - 20.5
34 - 35.5
14 - 15.5
19 - 20
29 - 30.5
LEAN CLAY (CL)
LEAN CLAY with SAND (CL)
LEAN CLAY (CL)
SILTY CLAY (CL-ML)
LEAN CLAY (CL)
ASTM D422 / ASTM C136
PROJECT NUMBER: 20165058
PROJECT: Standard at Fort Collins
SITE: Northeast of West Prospect Road and
Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-4
1901 Sharp Point Dr Ste C
Fort Collins, CO
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 20165058.GPJ 35159097 - ATTERBERG ISSUE.GPJ 7/26/16
LL PL PI
1 4
3/4 1/2
60
fine
1
2
2
4
4
13.58
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
coarse fine
U.HYDROMETERS. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
13
15
NP
19
14
10
9
NP
8
17
1.00
D100
Cc Cu
SILT OR CLAY
4
D30 D10 %Gravel %Sand
14 - 15.5
4 - 5.5
29 - 30.5
4 - 5.5
9 - 10.5
3/8 3 100
3 2 140
COBBLES GRAVEL SAND
USCS Classification
56.2
56.2
75.2
39.1
27.3
D60
coarse medium
Boring ID Depth
Boring ID Depth
GRAIN SIZE DISTRIBUTION
14 - 15.5
4 - 5.5
29 - 30.5
4 - 5.5
9 - 10.5
CLAYEY SAND (SC)
CLAYEY SAND (SC)
POORLY GRADED SAND with SILT and GRAVEL (SP-SM)
CLAYEY SAND (SC)
LEAN CLAY with SAND (CL)
ASTM D422 / ASTM C136
PROJECT NUMBER: 20165058
PROJECT: Standard at Fort Collins
SITE: Northeast of West Prospect Road and
Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-3
1901 Sharp Point Dr Ste C
Fort Collins, CO
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 20165058.GPJ 35159097 - ATTERBERG ISSUE.GPJ 7/26/16
31
41
34
22
47
45
30
13
15
NP
19
14
18
17
17
16
17
17
16
10
9
NP
8
17
13
24
17
6
30
28
14
37
31
9
49
70
85
75
91
87
93
38
51
LL USCS
1
2
2
4
4
5
5
6
6
6
7
7
ATTERBERG LIMITS RESULTS
ASTM D4318
14 - 15.5
4 - 5.5
29 - 30.5
4 - 5.5
9 - 10.5
19 - 20.5
34 - 35.5
14 - 15.5
19 - 20
29 - 30.5
34 - 35
39 - 40.5
PROJECT NUMBER: 20165058
PROJECT: Standard at Fort Collins
SITE: Northeast of West Prospect Road and
Sheely Drive
Fort Collins, Colorado
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
EXHIBIT: B-2
1901 Sharp Point Dr Ste C
Fort Collins, CO
LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. ATTERBERG LIMITS 20165058.GPJ TERRACON2015.GDT 7/26/16
CL-ML
Borehole name:
Test number:
Test date: (mm/dd/yyyy)
0
20
40
60
80
100
120
140
160
180
0 500 1000 1500 2000 2500
Volume (in³)
Pressure (psi)
Pressuremeter Test - Corrected Curve
Poisson's coefficient:
Pressiometric modulus E:
Test Results
0
20
40
60
80
100
120
140
160
180
0 100 200 300 400 500 600 700 800 900
Volume (in³)
Pressure (psi)
Pressuremeter Test - Corrected Curve
Borehole name:
Test number:
Test date: (mm/dd/yyyy)
0
20
40
60
80
100
120
140
160
180
0 500 1000 1500 2000 2500
Volume (in³)
Pressure (psi)
Pressuremeter Test - Corrected Curve
Poisson's coefficient:
Pressiometric modulus E:
Test Results
0
20
40
60
80
100
120
140
160
180
200
0 100 200 300 400 500 600 700 800 900
Volume (in³)
Pressure (psi)
Pressuremeter Test - Corrected Curve
Poisson's coefficient:
Pressiometric modulus E:
Test Results
0
20
40
60
80
100
120
140
160
180
200
0 100 200 300 400 500 600 700 800
Volume (in³)
Pressure (psi)
Pressuremeter Test - Corrected Curve
depth
POORLY GRADED SAND WITH SILTY
CLAY, fine to coarse grained,
yellowish-brown to brown, loose
LEAN CLAY WITH SAND, fine to coarse
grained, reddish-brown to yellowish-brown,
medium stiff
Sand and Gravel lense, inferred from drill
response
CLAYEY SAND (SC), reddish-brown to
yellowish-brown, stiff
INTERBEDDED SANDSTONE and
CLAYSTONE, grayish-brown to gray,
laminated bedding, firm to very hard; highly
weathered at 39 (CL)
Boring Terminated at 59.4 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4.25-inch (ID) hollow-stem auger
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/13/2016
BORING LOG NO. 7
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/13/2016
Exhibit: A-11
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5024.6 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
40
45
50
55
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.567821° Longitude: -105.091519°
20 feet while drilling
20.6 feet on 7/14/16
WATER LEVEL OBSERVATIONS
SITE:
Page 1 of 1
Advancement Method:
4-inch solid-stem auger
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/13/2016
BORING LOG NO. 6
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/13/2016
Exhibit: A-10
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5027.1 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.567387° Longitude: -105.091975°
21 feet while drilling
22 feet on 7/14/16
WATER LEVEL OBSERVATIONS
highly weathered, lean clay with sand
seams (CL), greenish-brown to
greenish-gray, stiff
INTERBEDDED SANDSTONE and
CLAYSTONE, yellowish-brown, laminated
bedding, medium hard to very hard, iron
oxides
Boring Terminated at 63.5 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4.25-inch (ID) hollow-stem auger (50.5 feet)
NX wireline core (50.5-63.5 feet)
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/12/2016
BORING LOG NO. 5
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/12/2016
Exhibit: A-9
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5024.6 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
40
45
50
55
60
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.567766° Longitude: -105.092389°
24 feet while drilling
WATER LEVEL OBSERVATIONS
WETHERED BEDROCK: Completely
weathered , interbedded sand with clay
seams, reddish-brown to greenish-gray,
weathered
INTERBEDDED SANDSTONE and
CLAYSTONE, grayish-brown to
greenish-brown, medium hard to very hard,
fine to medium-grained, laminated bedding,
iron oxides
Boring Terminated at 58.5 Feet
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4.25-inch (ID) hollow-stem auger (40 feet)
NX wireline core (40-58 feet)
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/12/2016
BORING LOG NO. 4
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/12/2016
Exhibit: A-8
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5022.4 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
40
45
50
55
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.568114° Longitude: -105.090574°
19 feet while drilling
WATER LEVEL OBSERVATIONS
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/13/2016
BORING LOG NO. 3
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/13/2016
Exhibit: A-7
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5021.6 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.568555° Longitude: -105.090427°
19 feet while drilling
18.7 feet on 7/14/16
WATER LEVEL OBSERVATIONS
Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4-inch solid-stem auger
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/13/2016
BORING LOG NO. 2
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/13/2016
Exhibit: A-6
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Surface Elev.: 5023.5 (Ft.)
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.568097° Longitude: -105.091181°
21 feet while drilling
19.4 feet on 7/14/16
WATER LEVEL OBSERVATIONS
GRAPHIC LOG
THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165058.GPJ TERRACON2015.GDT 7/29/16
Northeast of West Prospect Road and Sheely Drive
Fort Collins, Colorado
SITE:
Page 1 of 1
Advancement Method:
4.25-inch (ID) hollow-stem auger
Abandonment Method:
Borings backfilled with soil cuttings upon completion.
1901 Sharp Point Dr Ste C
Fort Collins, CO
Notes:
Project No.: 20165058
Drill Rig: CME-550
Boring Started: 7/13/2016
BORING LOG NO. 1
CLIENT: Landmark Collegiate Acquisitions, LLC
Athens, Georgia
Driller: B. Bradberry
Boring Completed: 7/13/2016
Exhibit: A-5
See Exhibit A-3 for description of field procedures.
See Appendix B for description of laboratory
procedures and additional data (if any).
See Appendix C for explanation of symbols and
abbreviations.
PROJECT: Standard at Fort Collins
RQD
(%)
UNCONFINED
COMPRESSIVE
STRENGTH (psf)
PERCENT FINES
WATER
CONTENT (%)
DRY UNIT
WEIGHT (pcf)
ATTERBERG
LIMITS
LL-PL-PI
Approximate Surface Elev: 5022.9 (Ft.) +/-
ELEVATION (Ft.)
SAMPLE TYPE
WATER LEVEL
OBSERVATIONS
DEPTH (Ft.)
5
10
15
20
25
30
35
40
45
50
55
60
RECOVERY (%)
SWELL-CONSOL /
LOAD (%/psf)
FIELD TEST
RESULTS
DEPTH
LOCATION See Exhibit A-2
Latitude: 40.568396° Longitude: -105.091401°
19 feet while drilling
14.4 feet on 7/14/16
WATER LEVEL OBSERVATIONS