HomeMy WebLinkAboutFORT COLLINS LDS TEMPLE - PDP - PDP120029 - SUBMITTAL DOCUMENTS - ROUND 1 - RECOMMENDATION/REPORTGeotechnical Engineering Report
FORT COLLINS TEMPLE
Southeast of South Timberline Road and East Trilby Road
Fort Collins, Colorado
August 19, 2011
Terracon Project No. 20115025
Prepared for:
The Church of Jesus Christ of Latter-Day Saints
Salt Lake City, Utah
Prepared by:
Terracon Consultants, Inc.
Fort Collins, Colorado
TABLE OF CONTENTS
Page
EXECUTIVE SUMMARY .............................................................................................................. ii
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 Profile ........................................................................................................ 3
3.2 Groundwater .......................................................................................................... 4
4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ....................................... 4
4.1 Geotechnical Considerations................................................................................. 4
4.1.1 Shallow Groundwater ................................................................................ 4
4.1.2 Permanent Dewatering .............................................................................. 5
4.1.3 Structural Recommendations .................................................................... 7
4.2 Earthwork .............................................................................................................. 7
4.2.1 Site Preparation ......................................................................................... 7
4.2.2 Import Material Specifications .................................................................... 8
4.2.3 Compaction Requirements ........................................................................ 9
4.2.4 Excavation and Trench Construction ......................................................... 9
4.2.5 Utility Trench Backfill ............................................................................... 10
4.2.6 Grading and Drainage ............................................................................. 10
4.2.7 Construction Considerations .................................................................... 11
4.2.8 Corrosion Protection ................................................................................ 11
4.3 Foundations ......................................................................................................... 12
4.3.1 Design Recommendations – Drilled Piers ............................................... 12
4.3.2 Construction Considerations – Drilled Piers ............................................ 13
4.3.3 Design Recommendations – Driven Piles ............................................... 13
4.3.4 Construction Considerations – Driven Piles ............................................ 14
4.3.5 Design Recommendations – Spread Footings ........................................ 15
4.3.6 Construction Considerations – Spread Footings ..................................... 16
4.4 Seismic Considerations ....................................................................................... 16
4.5 Interior Floor Systems ......................................................................................... 16
4.5.1 Design Recommendations – Slabs-on-grade (President’s residence) ... 17
4.5.2 Construction Considerations .................................................................. 17
4.6 Below-grade Construction ................................................................................... 18
4.7 Lateral Earth Pressures ....................................................................................... 18
4.8 Pavement Design and Construction .................................................................... 20
4.8.1 Drainage Adjacent to Pavements ............................................................ 21
4.8.2 Compliance .............................................................................................. 22
4.8.3 Pavement Performance ........................................................................... 22
4.8.4 Construction Considerations .................................................................... 23
5.0 GENERAL COMMENTS ................................................................................................. 23
TABLE OF CONTENTS (Cont’d)
APPENDIX A – FIELD EXPLORATION
Exhibit A-1 Field Exploration Description
Exhibit A-2 Boring Location Diagram
Exhibits A-3 to A-16 Logs of Borings
APPENDIX B – LABORATORY TESTING
Exhibit B-1 Laboratory Testing
Exhibit B-2 Atterberg Limits Test Results
Exhibits B-3 to B-13 Grain Size Test Results
Exhibits B-14 to B-19 Swell Consolidation Test Results
APPENDIX C – SUPPORTING DOCUMENTS
Exhibit C-1 General Notes
Exhibit C-2 Unified Soil Classification
Exhibit C-3 Rock Classification
Exhibit C-4 Laboratory Test Significance and Purpose
Exhibits C-5 and C-6 Report Terminology
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Responsive ■ Resourceful ■ Reliable ii
EXECUTIVE SUMMARY
A geotechnical engineering exploration has been performed for the proposed Church of Jesus
Christ of Latter-day Saints Fort Collins Temple to be constructed southeast of the intersection of
South Timberline Road and East Trilby Road in Fort Collins, Colorado. Fourteen (14) borings,
designated Exhibits A-3 through A-16, were performed to depths ranging from about 10½ feet to
40 feet below the existing ground surface. This report presents geotechnical recommendations
for design and construction of the proposed Fort Collins Temple building, Temple President’s
Residence, and associated pavements.
Based on the information obtained from our subsurface exploration and the laboratory testing
completed, the site appears suitable for the proposed construction; however, the following
geotechnical conditions will need to be considered:
Soils and bedrock encountered during our field exploration generally consisted of lean
clay with sand underlain by weathered to unweathered claystone bedrock.
The proposed Temple building may be supported on a deep foundation system
consisting of either drilled piers bottomed in bedrock or driven piles. A spread footing
foundation system is considered feasible for support of the Temple President’s
residence provided the bottom of the footings are constructed at least 3 feet above
measured groundwater levels and footing subgrade is judged stable.
Considering the very soft clay soils found in the proposed building envelope, we
recommend constructing a structurally-supported floor system for the proposed Temple
building. A concrete slab-on-grade floor may be used for the basement of the Temple
President’s residence provided the basement slab is at least 3 feet above measured
groundwater levels.
The basement in the Fort Collins Temple will extend below the observed groundwater
levels. Thus, permanent dewatering will be needed to lower groundwater levels below
permanent excavations.
The 2009 International Building Code (IBC), Table 1613.5.2 IBC seismic site
classification for this site is D.
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 this 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.
Responsive ■ Resourceful ■ Reliable 1
GEOTECHNICAL ENGINEERING REPORT
Fort Collins Temple
Southeast of South Timberline Road and East Trilby Road
Fort Collins, Colorado
Terracon Project No. 20115025
August 19, 2011
1.0 INTRODUCTION
A geotechnical engineering report has been completed for the proposed Church of Jesus Christ
of Latter-day Saints Fort Collins Temple to be located southeast of the intersection of South
Timberline Road and East Trilby Road in Fort Collins, Colorado.
As part of our subsurface exploration, a total of fourteen (14) borings were drilled at the site.
Five borings (designated as Boring Nos. 1 through 5) were drilled within the approximate
footprint of the proposed Temple, one boring (designated as Boring No. 14) was drilled within
the anticipated footprint of the proposed Temple President’s Residence, and eight borings
(designated as Boring Nos. 6 through 13) were drilled in pavement areas. The Logs of Borings
and Boring Location Diagram are included in Appendix A of this report.
The purpose of these services is to provide information and geotechnical engineering
recommendations relative to:
Subsurface soil and bedrock conditions Floor system design and construction
Groundwater conditions
Foundation design and construction
Earthwork
Lateral earth pressures
Seismic considerations
Pavement construction
Grading and Drainage
2.0 PROJECT INFORMATION
2.1 Project Description
ITEM DESCRIPTION
Site layout See Appendix A, Exhibit A-2, Boring Location Diagram
Proposed construction
The project will include a Temple building, Temple President’s
residence, and associated parking lots and paved access drives.
We understand the Temple will include a baptismal font constructed
at basement level and the Temple President’s residence may or
may not have plans for a basement.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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ITEM DESCRIPTION
Building construction
We anticipate the Temple building will be metal framed with stone
or brick veneer. The Temple President’s residence will be wood
framed.
Finished floor elevation Unknown at the time that this report was prepared
Maximum loads
Columns: Assumed not to exceed 900 kips
Walls: Assumed not to exceed 25 kips per linear foot of wall
Floor systems: Assumed to be a maximum of 200 psf
Grading
Preliminary Site Grading Plans were not available at the time this
report was written. Based upon the existing topography in the area
of proposed construction, we assume cuts and fills of less than
about 6 feet will be necessary to achieve desired grades. If a
basement is planned for the Temple President’s residence, we
anticipate an excavation of about 6 to 7 feet.
Infrastructure
Installation of underground utilities within about 5 feet of finished
site grades. Installation of pavements for drives and parking.
Traffic Loading
Light-duty (parking lots): Assumed to not exceed 15,000 ESALs
Heavy-duty (truck traffic): Assumed 75,000 ESALs
2.2 Site Location and Description
ITEM DESCRIPTION
Location
The project site is located southeast of the intersection of South
Timberline Road and East Trilby Road in Fort Collins, Colorado.
Existing improvements
The site is currently occupied by irrigated, farmed grasses with two
irrigation ditches running through the site. An existing single-family
residence is located in the southwestern portion of the site and a
barn is located in the south-central portion of the site with
associated gravel-surfaced drives and parking areas. There are
several large clusters of mature trees at various locations on the
property.
The project site is bordered to the west by residential development,
to the north by an existing Church of Jesus Christ of Latter-day
Saints, to the south and east by agricultural parcels.
Current ground cover The majority of the site is covered with irrigated grasses.
Existing topography
As shown on the topographic plans of the site provided to us, the
site is relatively flat sloping away from the north-south trending
irrigation ditch running through the site. Total relief across the site
is approximately 6 feet in the west and east direction and about 10
feet from north to south.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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3.0 SUBSURFACE CONDITIONS
3.1 Typical Profile
Based on the results of the borings, subsurface conditions encountered underlying the existing
ground surface on the project site can be generalized as follows:
Material Description Approximate Depth to Bottom
of Stratum (ft.) Consistency/Density/Hardness
Topsoil About ½ foot ---
Lean clay with sand About 23 to 25 feet Very soft to very stiff
Weathered claystone bedrock
About 27 to maximum depths
explored of up to about 31½ feet
Firm to medium hard
Claystone bedrock
To the maximum explored depth
of about 40½ feet in Boring No. 2
Medium hard to very hard
Subsurface conditions encountered at each boring location are indicated on the individual Logs
of Borings. Stratification boundaries on the Logs of Borings represent the approximate depths
of changes in soil and bedrock type, the transition between materials may be gradual. The Logs
of Borings are attached in Appendix A of this report.
Laboratory testing was conducted on selected samples of the soils and bedrock collected during
our field exploration and the test results are presented in Appendix B and on the attached Logs
of Borings.
3.2 Groundwater
The borings were observed while drilling and after completion for the presence and level of
groundwater. After a minimum of one day after drilling, supplemental groundwater levels were
measured in the borings. The groundwater levels are noted on the attached Logs of Borings,
and are summarized below.
Boring No. Depth to groundwater
while drilling (ft.)
Depth to groundwater
one day after drilling (ft.)
Elevation of groundwater
several days after drilling (ft.)
1 8 7 4912.5
2 6 5.5 4913.0
3 6 5.5 4911.8
4 6 5.5 4913.7
5 6 5.5 4912.3
6 9 Backfilled Backfilled
7 6 Backfilled Backfilled
8 6 Backfilled Backfilled
9 6.5 Backfilled Backfilled
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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Boring No. Depth to groundwater
while drilling (ft.)
Depth to groundwater
one day after drilling (ft.)
Elevation of groundwater
several days after drilling (ft.)
10 8.5 Backfilled Backfilled
11 7.5 Backfilled Backfilled
12 7 Backfilled Backfilled
13 Not encountered Backfilled Backfilled
14 9.5 9.5 4907.3
These observations represent groundwater conditions at the time of the field exploration, and
may not be indicative of other times or at other locations. It is also our opinion that groundwater
below this site is significantly impacted by the irrigation activities on the site. At the time of our
field study, the irrigation ditches were running full and irrigation on the site was occurring on a
regular basis. Groundwater levels can be expected to fluctuate with varying seasonal and
weather conditions, and other factors.
Groundwater level fluctuations occur due to seasonal variations in the 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 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.
4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION
4.1 Geotechnical Considerations
Based on the results of our study, it is our opinion that the site is suitable for the proposed
construction from a geotechnical point of view provided certain precautions and design and
construction recommendations outlined in this report are followed. We have identified
geotechnical conditions that could impact design and construction of the proposed structures
and other site improvements.
4.1.1 Shallow Groundwater
The shallow groundwater condition at the site will affect the construction of the foundations and
basements for the proposed Temple and Temple President’s residence. In addition, utility
excavations will most likely encounter groundwater. If groundwater is encountered during
construction, temporary dewatering wells may be required to advance and/or complete
excavations. It is also our opinion that a permanent dewatering system will be required.
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 building foundations, floor slabs 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 tri-axial geogrid materials in
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Responsive ■ Resourceful ■ Reliable 5
conjunction with gravel could also be considered and could be more cost effective. As an
alternative, consideration could also be given to chemically treating the subgrade.
Unstable subgrade conditions should be observed by the geotechnical engineer 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. The Owner should
understand that there are very soft, wet clay soils below this site that will require stabilization
prior to construction. It may be prudent to have a budget contingency with the site grading
contractor to incorporate additional efforts that will be necessary to achieve stable subgrade
soils.
Sewer under drains. Because of the relatively shallow groundwater level, and because of the
proposed future development of the overall site on the south and west of Majestic Court, we
recommend that an underdrain be installed in the sewer excavation. The underdrain should be
independent of the sewer line but placed at or near the sewer level. Stub-outs should be
provided so that underdrains at future residences can be connected to it. Ideally, the underdrain
would discharge by gravity into a detention pond at or near the lowest elevation on the overall
site.
We do not recommend that the temple permanent dewatering discharge be connected to this
underdrain, but discharge independently.
4.1.2 Permanent Dewatering
The basement in the Fort Collins Temple will extend below the observed groundwater levels.
Thus, permanent dewatering will 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 basement sub-floor level which is the ground surface below the bottom of
the basement structural floor support beams.
The flood irrigation being used at the site contributes to the current groundwater condition and
likely raises groundwater levels above those that would otherwise occur. However, in the
absence of the on-site irrigation practices there would still be relatively shallow groundwater.
This is because of the predominantly clayey subsurface soils setting over relatively shallow
bedrock combined with residential/urban development and irrigated farmland uphill from the
site.
Because the on-site clayey soils do not freely drain, it will take some time for the groundwater
levels to lower to long-term levels once the on-site surface irrigation ceases. Even then, it is
unlikely that the on-site groundwater levels will naturally fall below the recommended levels.
Therefore it should be assumed that the recommended dewatering system will need to operate
continually through the life of the Temple.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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We suggest that the dewatering system consist of a combination of drains and sumps. The
configuration of the system will depend on the size and proposed use of the basement. The
locations of the drains and/or sumps must consider maintenance accessibility.
A possible configuration would be a subsurface drain around the exterior of the basement
perimeter wall. 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 5 feet below the subbasement excavation level. The drain pipe should discharge into two
or more sumps accessible within the basement.
The drainage gravel should extend vertically over the drain pipes to at least two feet above the
highest groundwater levels observed in the soil borings. Thus, the drain gravel will extend into
the basement wall backfill. The basement wall adjacent to the drain gravel should be properly
waterproofed. The drain gravel must be isolated from the void space under the structural floor
so as not to flood this space.
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. 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:
Disposition of the developed water, which could be to a storm water detention basin.
Because the clayey soils are not free-draining, the amount of water removed should not
be large.
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.
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.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Responsive ■ Resourceful ■ Reliable 7
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 basement crawl space that would activate a flashing
warning light in the mechanical room or the laundry. Because the water inflow into the
dewatering system should be fairly slow, this type of system should provide sufficient
warning for maintenance to take place before the crawl space below the basement or
the basement itself become flooded.
4.1.3 Structural Recommendations
Based on the geotechnical engineering analyses, subsurface exploration and laboratory test
results, the proposed Temple building should be constructed on a deep foundation system
consisting of either drilled pier foundations bottomed in bedrock or driven pile foundations. We
believe the Temple President’s residence can be supported on a spread footing foundation
system provided the bottom of footings are constructed at least 3 feet above measured
groundwater levels and footing subgrade is judged stable.
A structurally-supported floor system should be used for the proposed Temple building. A slab-
on-grade may be utilized for the basement floor of the Temple President’s residence provided
the basement slab is constructed at least 3 feet above measured groundwater levels.
Design and construction recommendations for the foundation system and other earth connected
phases of the project are outlined in subsequent sections.
4.2 Earthwork
The following presents recommendations for site preparation, 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 and testing of engineered fills, subgrade preparation, proof-rolling, and
other geotechnical conditions exposed during the construction of the project.
4.2.1 Site Preparation
Strip and remove existing concrete, vegetation, unsuitable fills and other deleterious materials
from below proposed buildings, pavements, and areas planned to receive fill prior to
construction. All exposed surfaces should be free of mounds and depressions which could
prevent uniform compaction.
Stripped materials consisting of vegetation and organic materials should be wasted from the site
or used to revegetate landscaped areas or exposed slopes after completion of grading
operations.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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A site grading plan was not provided at the time this report was prepared. Terracon assumes
that site grading cuts and fills will not exceed about 6 feet at the site. All exposed areas which
will receive fill, once properly cleared and benched, should be scarified to a minimum depth of
10 inches, moisture conditioned to near optimum moisture content and compacted.
Demolition of the existing single-family residence located in the southwestern portion of the site
should include complete removal of the foundation system within the proposed construction
area. This should include removal of any loose backfill found adjacent to the existing
foundation. All materials derived from the demolition of the existing structure should be
removed from the site and should not be allowed for use in any on-site fills. Abandoned utilities
associated with the structure should be completely removed or grouted in-place. The type of
foundation system supporting the existing residence is not known. If the building is supported by
drilled piers, the existing piers should be truncated a minimum depth of 3 feet below areas of
planned new construction.
Although evidence of significant amounts of unsuitable fills or underground facilities such as
septic tanks, cesspools, basements and utilities was not observed during the site
reconnaissance, such features could be encountered during construction. If significant amounts
of unsuitable fills or underground facilities are encountered, such features should be removed
and the excavation thoroughly cleaned prior to backfill placement and/or construction.
The stability of the subgrade may be affected by precipitation, repetitive construction traffic or
other factors. If unstable conditions are encountered or develop during construction, workability
may be improved by scarifying and drying; however, allowing the clays to dry out below the
optimum moisture content is not recommended. If such conditions occur, the affected area
should be overexcavated and replaced with granular materials and/or non- to low expansive
materials. As an alternative, chemical treatment such as lime, fly ash, kiln dust, cement or
geotextiles could also be considered as a stabilization technique. Laboratory evaluation is
recommended to determine the effect of chemical stabilization on subgrade soils prior to
construction. Lightweight excavation equipment may be required to reduce subgrade pumping.
4.2.2 Import Material Specifications
Clean on-site soils or approved imported materials may be used as fill material. 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 15-50
Liquid Limit……………………………………………………30 (max)
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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Plastic Limit…………………………………………………..15 (max)
Maximum Expansive Potential (%)………………………..non-expansive*
*Measured on a sample compacted to approximately 95 percent of the ASTM D698 maximum dry density at
optimum water content. The sample is confined under a 100 psf surcharge and submerged.
4.2.3 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 8 to 10-inches or less in loose thickness
Compaction requirements (clay)
95 percent of the maximum dry unit weight as determined by
ASTM D 698
Moisture content cohesive soil
(clay)
0 to +3 % of the optimum moisture content
-1 to +2% of the optimum moisture content in pavement
areas
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 proof-rolled.
4.2.4 Excavation and Trench Construction
Excavations into the on-site soils will encounter very soft to very stiff clay soils and can
generally be performed using conventional excavation equipment. Excavations into the clays
above groundwater levels below the site can be expected to stand on relatively steep temporary
slopes during construction. However, excavations into clays below the water table may require
sloping or shoring of the excavation sides and temporary construction dewatering. 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.
Soils penetrated by the proposed excavations may vary significantly across the site. The soil
classifications are based solely on the materials encountered in the 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.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
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As a safety measure, it is recommended that all vehicles and soil piles be kept to a minimum
lateral distance from the crest of the slope equal to no less than the slope height. The exposed
slope face should be protected against the elements.
Depending upon depth of excavation and seasonal conditions, groundwater may be
encountered in excavations on the site. Pumping from sumps and/or sloping of excavations to
collection areas may be utilized to control water within excavations.
4.2.5 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 structure 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 backfilled with relatively clean materials and is properly
backfilled. 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 building should be effectively sealed to restrict water intrusion and flow
through the trenches that could migrate below the building. We recommend constructing an
effective clay “trench plug” that extends at least 5 feet out from the face of the building exterior.
The plug material should consist of clay compacted at a water content at or above the soils
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 the geotechnical engineer provide full-time
observation and compaction testing of trench backfill within building and pavement areas.
4.2.6 Grading and Drainage
All grades must be adjusted to provide positive drainage away from the buildings during
construction and maintained throughout the life of the proposed project. Infiltration of water into
utility or foundation excavations must be prevented during construction. Landscaped irrigation
adjacent to foundations should be minimized or eliminated. Water permitted to pond near or
adjacent to the perimeter of structures (either during or post-construction) can result in greater
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.
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Responsive ■ Resourceful ■ Reliable 11
Exposed ground should be sloped at a minimum of 10 percent grade for at least 5 feet beyond
the perimeter of the 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 exterior walls and in utility and sprinkler line trenches should be well compacted
and free of all construction debris to reduce the possibility of moisture infiltration. After building
construction 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. Drip irrigation
may be considered in these areas. Roof drains should discharge on pavements or be extended
away from the structure a minimum of 10 feet through the use of splash blocks or downspout
extensions. A preferred alternative is to have the roof drains discharge to storm sewers by solid
pipe or daylighted to a detention pond or other appropriate outfall.
4.2.7 Construction Considerations
Upon completion of grading operations, care should be taken to maintain the moisture content
of the subgrade prior to construction of pavements and exterior concrete flatwork. Construction
traffic over prepared subgrade should be minimized and avoided to the extent practical.
The site should also be graded to prevent ponding of surface water on the prepared subgrades
or in excavations. In areas where water is allowed to pond over a period of time, the affected
area should be removed and allowed to dry out; however, allowing the clays to dry out below
the optimum moisture content is not recommended. If such conditions occur, the affected area
should be overexcavated and replaced with granular materials and/or non- to low expansive
materials. As an alternative, chemical treatment such as lime, fly ash, kiln dust, cement or
geotextiles could also be considered as a stabilization technique.
Terracon should be retained during the construction phase of the project to observe earthwork
and to perform necessary tests and observations during site grading operations, excavations,
subgrade preparation, proof-rolling, placement and compaction of controlled compacted fills,
backfilling of excavations into the completed subgrade, and pavement construction.
4.2.8 Corrosion Protection
Results of water soluble sulfate testing performed on the existing soils indicated a negligible
value of less than 1 mg/l. Results of soluble sulfate testing indicate that ASTM Type I Portland
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cement is suitable for all project concrete on and below grade. However, if there is no (or
minimal) cost differential, use of ASTM Type II Portland cement is recommended for additional
sulfate resistance of construction concrete. Foundation concrete should be designed in
accordance with the provisions of Section 318, Chapter 4, of the ACI Design Manual.
4.3 Foundations
Several foundation alternatives were considered for the proposed buildings at this site. We
recommend constructing the Temple building on a deep foundation system consisting of either
drilled pier foundations bottomed in bedrock or driven piles. The Temple President’s residence
can be constructed on spread footings provided the bottoms of footings are constructed at least
3 feet above measured groundwater levels. Design recommendations for drilled piers bottomed
in bedrock, driven piles, and spread footings are presented in the following paragraphs.
4.3.1 Design Recommendations – Drilled Piers
Drilled pier and grade beam foundation systems are considered a suitable deep foundation
system for support of the proposed Temple building. Design recommendations for a drilled pier
foundation system are presented in the following paragraphs.
DESCRIPTION VALUE
Minimum pier length 30 feet
Minimum pier diameter 18 inches
Minimum bedrock embedment 1 8 feet
Maximum end-bearing pressure 15,000 psf
Skin friction (for portion of pier embedded in bedrock) 1,500 psf
Void Thickness (beneath grade beams, between piers) 4 inches
1. Drilled piers should be embedded into firm or harder bedrock materials.
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 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 L-pile, piers may be designed for the following
lateral load criteria:
PARAMETER CLAY BEDROCK
Unit weight (pci) 0.0637 0.0694
Average undrained shear strength (psf) 300 5,000
Coefficient of subgrade reaction, k (pci)* 30- static
20 - cyclic
2,000- static
800 – cyclic
Strain, 50 (%) 0.020 0.005
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4.3.2 Construction Considerations – Drilled Piers
Drilling to design depth should be possible with conventional single-flight power augers. However,
very moist to wet clays encountered in our borings on the site will require temporary steel casing
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. 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.
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.
It is our opinion drilled shafts should be roughened using shear rings. We recommend shear
rings be provided in the portion of each pier in the bedrock below a depth of about 23 feet.
Shear rings should be spaced a maximum of 30 inches on-center, with a minimum width of 4
inches and a depth of 3 inches into the sidewall of the pier. Shaft bearing surfaces must be
cleaned prior to concrete placement. A representative of the geotechnical engineer should
observe the bearing surface and shaft configuration.
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.
Pier-bearing surfaces must be cleaned prior to concrete placement. A representative of
Terracon should observe the bearing surface and pier configuration.
4.3.3 Design Recommendations – Driven Piles
Driven piles may also be considered as a deep foundation alternative for the proposed Temple
structure. Piles used for foundation support transmit structural loads to a stratum of
comparatively higher bearing capacity and should experience relatively small amounts of
movement.
The design capacity of a single driven pile is a function of several factors including the size and
type of pile and the engineering properties of the subsurface soils and bedrock. The most
effective means of verifying pile capacities for either tension or axial loads is through pile load
tests. Alternatively, dynamic driving formulas can be used to assess pile capacity on actual test
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or production piles. Preliminary foundation design can be based upon calculated capacities
utilizing soil strength criteria determined from the field and laboratory testing conducted during
exploration. Design recommendations for a driven pile foundation system are presented in the
following paragraphs.
Steel H-piles driven into the claystone bedrock to virtual refusal should be designed for a
maximum allowable capacity of 75 tons per pile. This capacity is based on using HP 10 x 57 piles
with a working stress of 9 ksi. Virtual refusal criteria as defined by the Colorado Department of
Transportation Standard Specifications for Road and Bridge Construction (2005 Edition) should
be specified for construction.
Estimated pile tip depth to develop the allowable pile capacity below the proposed Temple
building is about 35 feet below the existing ground surface. Individual pile settlement should be
on the order of 1/2-inch when designed according to the criteria presented in this report.
Axial and uplift pile capacities may be increased by one-third when considering wind and/or
earthquake loading.
Piles should be designed to resist lateral loads. To satisfy forces in the horizontal direction using
L-pile, piles may be designed for the lateral load criteria presented in the 4.3.1 Design
Recommendations – Drilled Piers section of this report.
Lateral resistance to horizontal forces can be provided by battered piles. The vertical and
horizontal components of the load will depend on the batter inclinations. Batters should not
exceed 1:4 (horizontal:vertical).
Groups of piles required to support concentrated loads will require appropriate reductions of the
axial, uplift and lateral capacities based on the effective envelope of the pile group. This reduction
can be avoided by spacing piles at a minimum distance of at least three diameters center to
center. Piles spaced less than three diameters center to center should be evaluated on an
individual basis to determine appropriate reductions in axial, uplift and lateral capacities.
The pile driving system should be analyzed using the wave equation to evaluate the potential for
overstressing the pile materials during driving. Dynamic analysis may also be used to evaluate
the driving resistance required to obtain the predicted design load.
4.3.4 Construction Considerations – Driven Piles
The contractor should select a driving hammer and cushion combination which is capable of
installing the selected piling without overstressing the pile material. The contractor should submit
the pile driving plan and the pile hammer-cushion combination to the engineer for evaluation of
the driving stresses in advance of pile installation.
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Some ground heave may be experienced as a result of pile driving at each site. Therefore, it is
recommended that the top elevations of the initial piles driven be surveyed. If any heave is noted
after the driving of subsequent piles, the piles should be redriven to their original top elevation.
This problem can be particularly acute in pile groups.
The pile hammer should be operated at the manufacturer's recommended stroke when
measuring penetration resistance. All piles should be provided with driving shoes to protect the
pile tip from damage when penetrating the dense granular soils. A representative of the
geotechnical engineer should observe pile driving operations on a full-time basis. Each pile
should be observed and checked for buckling, crimping and alignment in addition to recording
penetration resistance, depth of embedment, and general pile driving operations.
It may be prudent to verify the pile capacity during construction by performing a pile load test in
accordance with ASTM D1143, Standard Test Method for Piles Under Static Pile Compressive
Load.
4.3.5 Design Recommendations – Spread Footings
We believe the proposed Temple President’s residence can be constructed on a spread footing
foundation system provided the bottoms of footings are constructed at least 3 feet above
measured groundwater levels.
DESCRIPTION VALUE
Maximum net allowable soil bearing pressure 1 1,250 psf
Minimum dimensions
Column Wall Footing
24 inches 16 inches
Minimum embedment below finished grade for
frost protection 2
30 inches 30 inches
Estimated post-construction movement 3 about 1 inch about 1 inch
1. The net allowable soil bearing pressure applies to dead loads plus design live load conditions and
is the maximum pressure that should be transmitted to the bearing soils in excess of the minimum
surrounding overburden pressure at the footing base elevation. Assumes footing subgrade will be
judged stable and if unstable conditions are encountered, subgrade will be stabilized prior to
foundation construction.
2. For perimeter footings and footings beneath unheated areas. Interior column pads in heated areas
should bear at least 12 inches below the adjacent grade (or the top of the floor slab) for
confinement of the bearing materials and to develop the recommended bearing pressure.
3. Additional foundation movements could occur if surface water infiltrates the foundation soils;
therefore, proper drainage away from the foundation system should be provided in the final design,
during construction and maintained throughout the life of the structure.
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Footings should be proportioned to reduce differential foundation movement. Proportioning on
the basis of relative constant dead-load pressure can provide a means to reduce differential
movement between adjacent footings.
Footings and foundation walls should be reinforced as necessary to reduce the potential for
distress caused by differential foundation movement.
4.3.6 Construction Considerations – Spread Footings
To reduce the potential of “pumping” and softening of the foundation soils at the foundation
bearing level and the requirement for corrective work, we suggest the foundation excavation be
completed remotely with a track-hoe.
Where soils are loosened during excavation or in the forming process for the footings, or if
soft/low strength or otherwise unsuitable soils are present at foundation bearing depth, they
should be removed and replaced with engineered fill or re-compacted to at least 95 percent of
the maximum dry unit weight as determined by ASTM D698 at optimum to 3 percent above
optimum moisture content.
Completed foundation excavations should be observed by a representative of Terracon well in
advance of forming footings to confirm satisfactory bearing materials are present and
subsurface conditions are consistent with those encountered in our borings. 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
2009 International Building Code (IBC) 1 D 2
1. In general accordance with the 2009 International Building Code, Table 1613.5.2.
2. The 2009 International Building Code (IBC) requires a site soil profile determination extending a
depth of 100 feet for seismic site classification. The current scope requested does not include the
required 100 foot soil profile determination. The borings for the Temple extended to a maximum
depth of about 40 feet and this seismic site class definition considers that similar soil and bedrock
conditions exist below the maximum depth of the subsurface exploration. Additional exploration to
deeper depths could be performed to confirm the conditions below the current depth of exploration.
Alternatively, a geophysical exploration could be utilized in order to attempt to justify a higher seismic
site class; however, we believe this is unlikely.
4.5 Interior Floor Systems
We recommend a structurally-supported floor system for the proposed Temple building. A slab-
on-grade floor may be used for the Temple President’s residence provided the basement slab is
constructed at least 3 feet above measured groundwater levels.
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Subgrade soils beneath interior and exterior slabs and beneath pavements should be scarified,
moisture conditioned and compacted to a minimum depth of 8 inches. The moisture content and
compaction of subgrade soils should be maintained until slab or pavement construction.
4.5.1 Design Recommendations – Slabs-on-grade (President’s residence only)
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 or less 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 prepared as outlined in the 4.2 Earthwork section of this report.
Additional floor slab design and construction recommendations are as follows:
Positive separations and/or isolation joints should be provided between slabs and all
foundations, columns or utility lines to allow independent movement.
Control joints should be provided in slabs to control the location and extent of cracking.
A minimum 2-inch void space should be constructed above or below non-bearing
partition walls (if any) placed on the floor slab. Special framing details should be
provided at doorjambs and frames within partition walls to avoid potential distortion.
Partition walls should be isolated from suspended ceilings.
Interior trench backfill placed beneath slabs should be compacted in accordance with
recommended specifications outlined below.
The use of a vapor retarder should be considered beneath concrete slabs on grade that
will be covered with wood, tile, carpet or other moisture sensitive or impervious
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.
Floor slabs should not be constructed on frozen subgrade.
Other design and construction considerations, as outlined in Section 302.1R of the ACI
Design Manual, are recommended.
4.5.2 Construction Considerations
Movements of slab-on-grades using the above outlined alternatives will likely be reduced and
tend to be more uniform. The estimates outlined above assume that the other
recommendations in this report are followed. Additional movement could occur should the
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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 outlined in the 4.2.6 Grading and
Drainage section of this report be followed.
4.6 Below-Grade Construction
We understand the baptismal font for the proposed Temple will extend approximately 4 to 6 feet
below grade. Therefore, the excavation to the bottom of the crawl space below the baptismal
font will extend approximately 7 to 9 feet below grade. Groundwater was encountered at depths
of about 5½ to 7 feet below existing site grade in the test borings performed in the Temple
building area at the time of field exploration. It is our opinion a permanent dewatering system
will be necessary for the proposed Temple building. Recommendations for the permanent
dewatering system are presented in the 4.1.2 Permanent Dewatering section of this report.
It is also our understanding that the proposed Temple President’s residence may or may not
have a basement. We measured groundwater at a depth of about 9½ feet below the existing
ground surface in our boring drilled in the area of the proposed residence. To help control the
water level behind basement walls for the residence, installation of a perimeter drainage system
is recommended. The drainage system should be constructed around the exterior perimeter of
the basement foundation and sloped at a minimum 1/8 inch per foot to a suitable outlet, such as
a sump and pump system.
The drainage system should consist of a minimum 4-inch diameter perforated or slotted pipe,
embedded in free-draining gravel, placed in a trench at least 12 inches in width. The edge of
the trench should be sloped at a 1:1 slope beginning at the bottom outside edge of the footing.
The trench should not be cut vertically at the edge of the footing.
The drainage system should consist of a properly sized, perforated pipe that is embedded in
free-draining gravel and placed in a trench at least 12 inches in width. Gravel should extend a
minimum of 3 inches beneath the bottom of the pipe and at least 2 feet above the bottom of the
foundation wall. The system should be underlain with a polyethylene moisture barrier that is
sealed to the foundation walls and extended to at least the edge of the backfill zone. The gravel
should be covered with drainage fabric prior to placement of foundation backfill.
4.7 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. The "at-rest" condition assumes no wall movement. The
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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)
At-Rest (Ko)
Granular - 0.50
Lean Clay - 0.64
60
75
(0.50)S
(0.64)S
(60)H
(75)H
Passive (Kp)
Granular - 3.0
Lean Clay - 2.1
360
250
---
---
---
---
Applicable conditions to the above include:
For passive earth pressure to develop, wall must move horizontally to mobilize
resistance.
Uniform surcharge, where S is surcharge pressure
In-situ soil backfill weight a maximum of 120 pcf
Horizontal backfill, compacted to at least 95 percent of maximum dry unit weight as
determined by ASTM D 698
Loading from heavy compaction equipment not included
No hydrostatic pressures acting on wall
No dynamic loading
No safety factor included in soil parameters
Ignore passive pressure in frost zone
Foundation Wall
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To control hydrostatic pressure behind the wall we recommend that a drain be installed at the
foundation wall. Recommendations for drains associated with a permanent dewatering system
and below-grade construction are presented in the 4.1.2 Permanent Dewatering and 4.6
Below-Grade Construction sections of this report, respectively.
4.8 Pavement Design and Construction
Design of privately maintained pavements for the project has been based on the procedures
outlined by the Asphalt Institute (AI) and the American Concrete Institute (ACI). If improvements
to public roadways are anticipated, a pavement design report meeting the City of Fort Collins
specifications (Larimer County Urban Area Street Standards) will need to be prepared for
submittal, subsequent to final grading.
We assumed the following design parameters for Asphalt Institute flexible pavement thickness
design:
Automobile Parking Areas
Parking stalls and parking lots for cars and pick-up trucks, up to 200 stalls
Main Traffic Corridors
Parking lots with a maximum of 25 trucks per day
Subgrade Soil Characteristics
USCS Classification – CL (Poor Subgrade)
We assumed the following design parameters for ACI rigid pavement thickness design based
upon the average daily truck traffic (ADTT):
Automobile Parking Areas
ACI Category A-1: Automobile parking with an ADTT of 1 over 20 years
Main Traffic Corridors
ACI Category B: Commercial entrance and service lanes with an ADTT of
25 over 20 years
Subgrade Soil Characteristics
USCS Classification – CL
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.
In our opinion, a full depth asphalt concrete section over a prepared clay subgrade should not
be used on this site. Recommended alternatives for flexible and rigid pavements are
summarized for each traffic area as follows:
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Traffic Area
Alternative
Recommended Pavement Thickness (Inches)
Asphalt
Concrete
Surface
Aggregate
Base
Course
Portland
Cement
Concrete
Total
Automobile Parking
(AI Class I and ACI Category A)
A 4 6 10
B 6 6
Main Traffic Corridors
(AI Class III and ACI Category B)
A 5 6 11
B 6 6
* Minimum pavement section thickness per ACI
The placement of a partial pavement thickness for use during construction is not suggested
without a detailed pavement analysis incorporating construction traffic. In addition, we should
be contacted to confirm the traffic assumptions outlined above. If the actual traffic varies from
the assumptions outlined above, modification of the pavement section thickness will be
required.
For areas subject to concentrated and repetitive loading conditions 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 7 inches underlain by at least 4 inches of
crushed stone. Prior to placement of the crushed stone, the areas should be thoroughly proof-
rolled. For dumpster pads, the concrete pavement area should be large enough to support the
container and tipping axle of the refuse truck.
For analysis of pavement costs, the following specifications should be considered for each
pavement component:
Colorado Department of
Pavement Component Transportation Criteria
Asphalt Concrete Surface ......................................................................... Grading S or SX
Aggregate Base Course ................................................................................... Class 5 or 6
Portland Cement Concrete ...................................................................................... Class P
4.8.1 Drainage Adjacent to Pavements
The clay soils will likely lose stability with increases in moisture content. Therefore, to reduce
pavement distress due to wetting of the subgrade in areas of water intensive landscaping or
other nearby water sources (or if aggregate base course is used) located adjacent to
pavements, we recommend shoulder drains be considered. The drain system should consist of
a properly sized pipe embedded in free-draining material directed to a suitable outfall such as
an underdrain or storm sewer.
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4.8.2 Compliance
Recommendations for pavement design and construction presented depend upon compliance
with recommended material specifications. To assess compliance, observation and testing
should be performed under the observation of the geotechnical engineer.
4.8.3 Pavement Performance
The performance of all pavements can be enhanced by minimizing excess moisture which can
reach the subgrade soils. Future performance of pavements at this site will be dependent upon
several factors, including:
Maintaining stable moisture content of the subgrade soils both before and after
pavement construction; and
Providing for a planned program of preventative maintenance.
Since the clay soils on the site have shrink/swell characteristics, pavements could crack in the
future primarily because of expansion of the soils and bedrock when subjected to an increase in
moisture content to the subgrade. The cracking, while not desirable, does not necessarily
constitute structural failure of the pavement, provided that timely maintenance, such as crack
sealing is performed. Excessive movement and cracking could result if the subgrade soils are
allowed to dry out before paving and subsequently become rewetted.
The performance of all pavements can be enhanced by minimizing excess moisture, which can
reach the subgrade soils. The following recommendations should be considered at minimum:
Site grading at a minimum 2 percent grade onto or away from the pavements;
Water should not be allowed to pond behind curbs;
Compaction of any utility trenches for landscaped areas to the same criteria as the
pavement subgrade;
Sealing all landscaped areas in or adjacent to pavements to minimize or prevent
moisture migration to subgrade soils;
Placing compacted backfill against the exterior side of curb and gutter; and
Placing shoulder or edge drains in pavement areas adjacent to water sources.
Preventative maintenance should be planned and provided for an ongoing pavement
management program in order to enhance future pavement performance. Preventative
maintenance activities are intended to slow the rate of pavement deterioration and to preserve
the pavement investment.
Preventative maintenance consists of both localized maintenance (e.g. crack 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
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highest return on investment for pavements.
4.8.4 Construction Considerations
Site grading is generally accomplished early in the construction phase. However, as
construction proceeds, the subgrade may be disturbed due to utility excavations, construction
traffic, desiccation, or rainfall. 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 excessive rutting. If
disturbance has occurred, pavement subgrade areas should be reworked, moisture conditioned,
and properly compacted to the recommendations in this report immediately prior to paving.
We recommend the pavement areas be rough graded and then thoroughly proof-rolled with a
loaded tandem axle dump truck prior to final grading and paving. Particular attention should be
paid to high traffic areas that were rutted and disturbed earlier and to areas where backfilled
trenches are located. Areas where unsuitable conditions are located should be repaired by
removing and replacing the materials with properly compacted fills. All pavement areas should
be moisture conditioned and properly compacted to the recommendations in this report
immediately prior to paving.
The placement of a partial pavement thickness for use during construction is not recommended
without a detailed pavement analysis incorporating construction traffic. In addition, if the actual
traffic varies from the assumptions outlined above, we should be contacted to confirm and/or
modify the pavement thickness recommendations outlined above.
.
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 should also be retained to provide testing and
observation during site grading, excavation, fill placement, as well as foundation and
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 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, bacteria) assessment of the site or identification or
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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.
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 are planned in the nature, design, or location of the project as outlined in
this report, 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
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Exhibit A-1
Field Exploration Description
The location of borings was based upon the proposed development shown on the provided site
plan. The borings were located in the field by Terracon personnel measuring from property
lines and existing site features. The accuracy of the boring locations should only be assumed to
the level implied by the methods used.
The borings were drilled with a CME-75 truck-mounted drill rig with solid-stem augers. During
the drilling operations, lithologic logs of the borings were recorded by the field engineer.
Relatively undisturbed samples were obtained at selected intervals utilizing a 2-inch outside
diameter split-spoon sampler (RS) and a 3-inch outside diameter ring-barrel sampler (RS).
Disturbed bulk samples (BS) were obtained from auger cuttings. 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 and can be correlated to the 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 soils moisture content. 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. Some settlement of the backfill may occur and
should be repaired as soon as possible.
A-2
BORING LOCATION DIAGRAM Exhibit No.
FORT COLLINS TEMPLE
Southeast of South Timberline Road and Trilby Road
Fort Collins, Colorado
Project Manager:
Drawn By:
Checked By:
Approved By:
EDB
EDB
DJJ
DJJ
Project No.
Scale:
File Name:
Date:
20115025
1”=120’
8/19/2011
301 North Howes Street Fort Collins, Colorado 80521
PH. (970) 484-0359 FAX. (970) 484-0454
0’ 60’ 120’
GRAPHIC SCALE
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND
IS NOT INTENDED FOR CONSTRUCTION PURPOSES
1
APPROXIMATE BORING LOCATION
14
2
6
8
5
4
13
11
12
10
3
7
1
9
4919
4894.5
4889
0.5
25
30.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to very stiff, moist to wet,
brown
WEATHERED CLAYSTONE BEDROCK
silty, firm to medium hard, moist, olive,
brown, gray
BOTTOM OF BORING
1650
-200 = 77
LL = 34
PI = 18
1
2
3
4
5
6
7
RS
RS
RS
SS
SS
SS
SS
CL
CL
CL
CL
CL
9
7
2
5
5
11
23
22
23
25
23
25
23
22
100
97
96
BORING STARTED 8-5-11
8 WD AD
SITE
CLIENT
WL
WL
4918
4895
4891.5
4878
0.5
23.5
27
40.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to stiff, moist to wet, brown
WEATHERED CLAYSTONE BEDROCK
silty, firm to medium hard, moist, olive,
brown, gray
CLAYSTONE BEDROCK
silty, medium hard to hard, slightly moist,
olive, brown, gray, rust
BOTTOM OF BORING
1570
-200 = 79
LL = 37
PI = 23
1
2
3
4
5
6
7
8
RS
RS
SS
SS
SS
SS
SS
SS
CL
CL
CL
CL
CL
5
3
1
6
8
18
52
29
23
25
27
22
24
22
18
23
98
4916.8
4894.3
4891.8
0.5
23
25.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to stiff, moist to wet, brown
WEATHERED CLAYSTONE BEDROCK
silty, firm to medium hard, moist, olive,
brown, gray
BOTTOM OF BORING
1180 -200 = 73
LL = 35
PI = 19
1
2
3
4
5
6
RS
RS
SS
SS
SS
SS
CL
CL
CL
CL
CL
4
4
0
2
7
23
24
24
28
29
22
22
98
98
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
4918.7
4896.2
4893.7
0.5
23
25.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to medium stiff, moist to wet,
brown
WEATHERED CLAYSTONE BEDROCK
silty, firm to medium hard, moist, olive,
brown, gray
BOTTOM OF BORING
2480 -200 = 83
LL = 45
PI = 28
1
2
3
4
5
6
RS
RS
SS
SS
SS
SS
CL
CL
CL
CL
CL
9
6
5
2
5
9
21
23
24
23
27
25
99
100
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
4917.3
4892.8
4891.8
4887.3
0.5
25
26
30.5
TOPSOIL
LEAN CLAY with SAND
silty, soft to stiff, moist to wet, brown
CLAYEY GRAVEL with SAND
medium dense, wet, brown, gray, rust
CLAYSTONE BEDROCK
silty, medium hard, slightly moist, olive,
brown, gray, rust
BOTTOM OF BORING
-200 = 75
LL = 40
PI = 25
1
2
3
4
5
6
7
RS
RS
SS
SS
SS
SS
SS
CL
CL
CL
CL
CL
7
5
3
5
3
11
33
24
23
27
25
23
16
20
100
100
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
4917.3
4907.3
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to medium stiff, moist to wet,
brown
BOTTOM OF BORING
-200 = 85
LL = 40
PI = 24
1
2
3
RS
RS
SS
CL
CL
CL
5
3
0
23
29
29
94
91
BORING STARTED 8-5-11
9 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-8
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4917.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
4916.1
4906.1
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to medium stiff, moist to wet,
brown
BOTTOM OF BORING
-200 = 80
LL = 38
PI = 23
1
2
3
RS
RS
SS
CL
CL
CL
7
5
0
21
25
27
98
95
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-9
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4916.6 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
4915.3
4905.3
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, soft, moist to wet, brown
BOTTOM OF BORING
1
2
3
RS
RS
SS
CL
CL
CL
9
4
2
19
22
26
101
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-10
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4915.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 8
PERCENT FINES
ATTERBERG LIMITS,
%
4915.3
4905.3
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, soft to medium stiff, moist to wet,
brown
BOTTOM OF BORING
-200 = 75
LL = 37
PI = 23
1
2
3
SS
SS
SS
CL
CL
CL
4
2
3
23
26
26
BORING STARTED 8-5-11
6.5 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-11
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4915.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 9
4917.7
4907.7
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, soft to stiff, moist to wet, brown
BOTTOM OF BORING
1
2
3
SS
SS
SS
CL
CL
CL
5
7
2
21
21
25
BORING STARTED 8-5-11
8.5 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-12
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4918.2 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 10
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
4913.8
4903.8
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to stiff, moist to wet, brown
BOTTOM OF BORING
-200 = 83
LL = 39
PI = 23
1
2
3
RS
RS
SS
CL
CL
CL
11
6
1
19
24
30
106
97
BORING STARTED 8-5-11
7.5 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-13
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4914.3 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
4913.8
4903.8
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, very soft to medium stiff, moist to wet,
brown
BOTTOM OF BORING
-200 = 77
LL = 39
PI = 23
1
2
3
RS
RS
SS
CL
CL
CL
9
6
1
20
21
28
99
102
BORING STARTED 8-5-11
7 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-14
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4914.3 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
4917.3
4907.3
0.5
10.5
TOPSOIL
LEAN CLAY with SAND
silty, soft to very stiff, moist to wet, brown
BOTTOM OF BORING
1
2
3
RS
RS
RS
CL
CL
CL
22
13
3
13
17
27
107
94
BORING STARTED 8-5-11
None WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-15
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
Backfilled
RIG EDB
Approx. Surface Elevation: 4917.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 13
PERCENT FINES
ATTERBERG LIMITS,
4916.3
4891.3
0.5
25.5
TOPSOIL
LEAN CLAY with SAND
silty, soft to very stiff, moist to wet, brown
BOTTOM OF BORING
-200 = 76
LL = 38
PI = 21
1
2
3
4
5
6
RS
RS
RS
SS
SS
SS
CL
CL
CL
CL
CL
CL
16
17
4
14
16
14
15
17
24
112
95
BORING STARTED 8-5-11
9.5 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-16
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
APPENDIX B
LABORATORY TESTING
Geotechnical Engineering Report
Fort Collins Temple ■ Fort Collins, Colorado
August 19, 2011 ■ Terracon Project No. 20115025
Exhibit B-1
Laboratory Testing
Samples retrieved during the field exploration were returned to the laboratory for observation by
the project geotechnical engineer, and were classified in general accordance with the Unified
Soil Classification System described in Appendix C. Samples of bedrock were classified in
accordance with the general notes for Rock Classification.
At this time, an applicable laboratory-testing program was formulated to determine engineering
properties of the subsurface materials. Following the completion of the laboratory testing, the
field descriptions were confirmed or modified as necessary, and Logs of Borings were prepared.
These logs are presented in Appendix A.
Laboratory test results are presented in Appendix B. These results were used for the
geotechnical engineering analyses and the development of foundation and earthwork
recommendations. All laboratory tests were performed in general accordance with the
applicable local or other accepted standards.
Selected soil and bedrock samples were tested for the following engineering properties:
Water content
Dry density
Expansion/Consolidation
Unconfined compression strength
Grain size
Atterberg limits
Water-soluble sulfate content
0
10
20
30
40
50
60
0 20 40 60 80 100
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
LEAN CLAY with SAND(CL)
77
79
73
83
75
85
80
75
83
77
76
Specimen Identification PI
ML
CL
MH
CH
CL-ML
P
L
A
S
T
I
C
I
T
Y
I
N
D
E
X
14.0ft
19.0ft
4.0ft
2.0ft
9.0ft
2.0ft
4.0ft
4.0ft
2.0ft
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
16
GRAIN SIZE DISTRIBUTION
22.8 77.2
1
2
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
18
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-3
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
14
GRAIN SIZE DISTRIBUTION
21.4 78.6
2
4.75
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
23
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-4
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
16
GRAIN SIZE DISTRIBUTION
26.9 73.1
3
2
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
19
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
17
GRAIN SIZE DISTRIBUTION
17.1 82.9
4
4.75
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
28
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-6
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.1
4 3 14
2 8
COBBLES
GRAVEL
15
GRAIN SIZE DISTRIBUTION
24.8 75.1
5
9.5
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
25
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-7
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
16
GRAIN SIZE DISTRIBUTION
14.8 85.2
6
2
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
24
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY(CL)
fine
Exhibit B-8
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
15
GRAIN SIZE DISTRIBUTION
19.7 80.3
7
2
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
23
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-9
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
14
GRAIN SIZE DISTRIBUTION
25.0 75.0
9
4.75
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
23
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-10
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
16
GRAIN SIZE DISTRIBUTION
16.6 83.4
11
4.75
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
23
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-11
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
16
GRAIN SIZE DISTRIBUTION
23.1 76.9
12
2
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
23
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-12
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
SAND
SILT OR CLAY
200
LL PL
D10
fine
6 1 6
3/4 1/2
3/8
PI Cc Cu
0.0
4 3 14
2 8
COBBLES
GRAVEL
17
GRAIN SIZE DISTRIBUTION
23.5 76.5
14
4.75
50 60 100
coarse
1.5
GRAIN SIZE IN MILLIMETERS
PERCENT FINER BY WEIGHT
Classification
coarse
Specimen Identification D100
4
21
10
D30
16 20
30 40
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
LEAN CLAY with SAND(CL)
fine
Exhibit B-13
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-14
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
1 2.0 ft LEAN CLAY with SAND (CL) 100 22
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-15
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
1 9.0 ft LEAN CLAY with SAND (CL) 96 25
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-16
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
2 4.0 ft LEAN CLAY with SAND (CL) 97 25
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-17
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
3 2.0 ft LEAN CLAY with SAND (CL) 98 24
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-18
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
4 4.0 ft LEAN CLAY with SAND (CL) 100 23
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
-10
-8
-6
-4
-2
0
2
4
100 1,000 10,000
AXIAL STRAIN, %
PRESSURE, psf
SWELL CONSOLIDATION TEST
Date: 8-19-11 Exhibit B-19
SpecimenClassification Identification , pcf WC,%
Notes: Water added at 1,000 psf.
5 2.0 ft LEAN CLAY with SAND (CL) 100 24
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_CONSOL_STRAIN 20115025.GPJ DENVER 031610.GDT 8/19/11
APPENDIX C
SUPPORTING DOCUMENTS
GENERAL NOTES
DRILLING & SAMPLING SYMBOLS:
SS: Split Spoon - 1-3/8" I.D., 2" O.D., unless otherwise noted HS: Hollow Stem Auger
ST: Thin-Walled Tube - 2" O.D., unless otherwise noted PA: Power Auger
RS: Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger
DB: Diamond Bit Coring - 4", N, B RB: Rock Bit
BS: Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary
The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch
penetration with a 140-pound hammer falling 30 inches is considered the “Standard Penetration” or “N-value”. For 3” O.D. ring
samplers (RS) the penetration value is reported as the number of blows required to advance the sampler 12 inches using a 140-
pound hammer falling 30 inches, reported as “blows per foot,” and is not considered equivalent to the “Standard Penetration” or
“N-value”.
WATER LEVEL MEASUREMENT SYMBOLS:
WL: Water Level WS: While Sampling
WCI: Wet Cave in WD: While Drilling
DCI: Dry Cave in BCR: Before Casing Removal
AB: After Boring ACR: After Casing Removal
Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at
other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of
groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-
term observations.
DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified 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.
FINE-GRAINED SOILS COARSE-GRAINED SOILS BEDROCK
(RS)
Blows/Ft.
(SS)
Blows/Ft.
Consistency
(RS)
Blows/Ft.
(SS)
Blows/Ft.
Relative
Density
(RS)
Blows/Ft.
(SS)
Blows/Ft. Consistency
< 3 0-2 Very Soft 0-6 < 3 Very Loose < 30 < 20 Weathered
3-4 3-4 Soft 7-18 4-9 Loose 30-49 20-29 Firm
5-9 5-8 Medium Stiff 19-58 10-29 Medium Dense 50-89 30-49 Medium Hard
10-18 9-15 Stiff 59-98 30-50 Dense 90-119 50-79 Hard
19-42 16-30 Very Stiff > 98 > 50 Very Dense > 119 > 79 Very Hard
> 42 > 30 Hard
RELATIVE PROPORTIONS OF SAND AND
GRAVEL
GRAIN SIZE TERMINOLOGY
Descriptive Terms of
Other Constituents
Percent of
Dry Weight
Major Component
of Sample Particle Size
Trace < 15 Boulders Over 12 in. (300mm)
With 15 – 29 Cobbles 12 in. to 3 in. (300mm to 75 mm)
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Soil Classification
Group
Symbol
Group NameB
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% finesC
Cu 4 and 1 Cc 3E GW Well graded gravelF
Cu 4 and/or 1 Cc 3E GP Poorly graded gravelF
Gravels with Fines More
than 12% finesC
Fines classify as ML or MH GM Silty gravelF,G, H
Fines classify as CL or CH GC Clayey gravelF,G,H
Sands
50% or more of coarse
fraction passes
No. 4 sieve
Clean Sands
Less than 5% finesD
Cu 6 and 1 Cc 3E SW Well graded sandI
Cu 6 and/or 1 Cc 3E SP Poorly graded sandI
Sands with Fines
More than 12% finesD
Fines classify as ML or MH SM Silty sandG,H,I
Fines classify as CL or CH SC Clayey sandG,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” lineJ CL Lean clayK,L,M
PI 4 or plots below “A” lineJ ML SiltK,L,M
Organic
Liquid limit - oven
dried
0.75 OL
Organic clayK,L,M,N
Liquid limit - not
dried
Organic siltK,L,M,O
Silts and Clays
Liquid limit 50 or more
Inorganic PI plots on or above “A” line CH Fat clayK,L,M
PI plots below “A” line MH Elastic siltK,L,M
Organic Liquid limit - oven dried
0.75 OH
Organic clayK,L,M,P
Liquid limit - not dried Organic siltK,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-in. (75-mm) sieve
B If field sample contained cobbles or boulders, or both, add “with cobbles
or boulders, or both” to group name.
C Gravels with 5 to 12% fines require dual symbols: GW-GM well graded
ROCK CLASSIFICATION
(Based on ASTM C-294)
Sedimentary Rocks
Sedimentary rocks are stratified materials laid down by water or wind. The sediments may
be composed of particles or pre-existing rocks derived by mechanical weathering,
evaporation or by chemical or organic origin. The sediments are usually indurated by
cementation or compaction.
Chert Very fine-grained siliceous rock composed of micro-crystalline or
cyrptocrystalline quartz, chalcedony or opal. Chert is various colored,
porous to dense, hard and has a conchoidal to splintery fracture.
Claystone Fine-grained rock composed of or derived by erosion of silts and clays or
any rock containing clay. Soft massive and may contain carbonate
minerals.
Conglomerate Rock consisting of a considerable amount of rounded gravel, sand and
cobbles with or without interstitial or cementing material. The cementing
or interstitial material may be quartz, opal, calcite, dolomite, clay, iron
oxides or other materials.
Dolomite A fine-grained carbonate rock consisting of the mineral dolomite
[CaMg(CO3)2]. May contain noncarbonate impurities such as quartz,
chert, clay minerals, organic matter, gypsum and sulfides. Reacts with
hydrochloric acid (HCL).
Limestone A fine-grained carbonate rock consisting of the mineral calcite (CaCO3).
May contain noncarbonate impurities such as quartz, chert, clay minerals,
organic matter, gypsum and sulfides. Reacts with hydrochloric acid
(HCL).
Sandstone Rock consisting of particles of sand with or without interstitial and
cementing materials. The cementing or interstitial material may be
quartz, opal, calcite, dolomite, clay, iron oxides or other material.
Shale Fine-grained rock composed of or derived by erosion of silts and clays or
any rock containing clay. Shale is hard, platy, of fissile may be gray,
black, reddish or green and may contain some carbonate minerals
(calcareous shale).
Siltstone Fine grained rock composed of or derived by erosion of silts or rock
containing silt. Siltstones consist predominantly of silt sized particles
(0.0625 to 0.002 mm in diameter) and are intermediate rocks between
claystones and sandstones and may contain carbonate minerals.
Exhibit C-3
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 Sulphate 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 possess sufficient cohesion to permit testing in the
unconfined state.
Bearing Capacity
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-5
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.
Exhibit C-6
Analysis for
Foundations
Water Content Used to determine the quantitative amount of water in a soil
mass.
Index Property Soil
Behavior
Exhibit C-4
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.
HIf 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.
MIf 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.
Exhibit C-2
Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm)
Sand
Silt or Clay
#4 to #200 sieve (4.75mm to 0.075mm)
Passing #200 Sieve (0.075mm)
RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION
Descriptive Terms of
Other Constituents
Percent of
Dry Weight Term Plasticity Index
Trace
With
Modifiers
< 5
5 – 12
> 12
Non-plastic
Low
Medium
High
0
1-10
11-30
30+
Exhibit C-1
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
14
D60
medium
4.0ft
4.0 ft 38
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
12
D60
medium
4.0ft
4.0 ft 39
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
11
D60
medium
2.0ft
2.0 ft 39
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
9
D60
medium
4.0ft
4.0 ft 37
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
7
D60
medium
4.0ft
4.0 ft 38
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
6
D60
medium
2.0ft
2.0 ft 40
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
5
D60
medium
9.0ft
9.0 ft 40
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
4
D60
medium
2.0ft
2.0 ft 45
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
3
D60
medium
4.0ft
4.0 ft 35
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
2
D60
medium
19.0ft
19.0 ft 37
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
3
%Gravel %Sand %Silt
Specimen Identification
140
%Clay
Date: 8-19-11
HYDROMETER
1
D60
medium
14.0ft
14.0 ft 34
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_GRAIN_SIZE 20115025.GPJ DENVER 031610.GDT 8/19/11
4.0ft
4.0ft
LIQUID LIMIT
1
2
3
4
5
6
7
9
11
12
14
34
37
35
45
40
40
38
37
39
39
38
16
14
16
17
15
16
15
14
16
16
17
18
23
19
28
25
24
23
23
23
23
21
LL PL %Fines
ATTERBERG LIMITS RESULTS
Classification
Project: Fort Collins Temple
Proj. No. 20115025
Site: South Timberline Road and East Trilby Road, Fort Collins, Colorado
TC_ATTERBERG_LIMITS 20115025.GPJ DENVER 031610.GDT 8/19/11
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
9.5
RIG EDB
Approx. Surface Elevation: 4916.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 14
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
GRAPHIC LOG
BORING LOG NO. 12
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
BORING LOG NO. 11
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
GRAPHIC LOG
BORING LOG NO. 7
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
GRAPHIC LOG
BORING LOG NO. 6
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-7
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
5.5
RIG EDB
Approx. Surface Elevation: 4917.8 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 5
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
30
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
8-5-11
DESCRIPTION
Exhibit A-6
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
5.5
RIG EDB
Approx. Surface Elevation: 4919.2 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 4
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
DESCRIPTION
Exhibit A-5
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
5.5
RIG EDB
Approx. Surface Elevation: 4917.3 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 3
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
97
BORING STARTED 8-5-11
6 WD AD
SITE
CLIENT
WL
WL
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-4
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
5.5
RIG EDB
Approx. Surface Elevation: 4918.5 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 2
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
30
35
40
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf
APPROVED
The stratification lines represent the approximate boundary lines
Page 1 of 1
UNCONFINED
STRENGTH, psf
TESTS
8-5-11
DESCRIPTION
Exhibit A-3
WATER LEVEL OBSERVATIONS, ft
The Church of Jesus Christ of Latter-Day Saints
20115025
CME 75
EDB PROJ. NO.
LOGGED
PROJECT
BORING COMPLETED
* 140lb. SPT automatic hammer
7
RIG EDB
Approx. Surface Elevation: 4919.5 ft
between soil and rock types: in-situ, the transition may be gradual.
Fort Collins Temple
South Timberline Road and East Trilby Road
Fort Collins, Colorado
GRAPHIC LOG
BORING LOG NO. 1
PERCENT FINES
ATTERBERG LIMITS,
%
BOREHOLE WITH ATTERBERG LIMITS 20115025.GPJ DENVER TEMPLATE 8-5-11.GDT 8/19/11
TYPE
NUMBER
DEPTH, ft.
SAMPLES
USCS SYMBOL
5
10
15
20
25
30
BLOWS / ft.*
RECOVERY, in.
WATER
CONTENT, %
DRY UNIT WT, pcf