HomeMy WebLinkAboutNORTHBROOK PATIO HOMES AT FAIRBROOKE PUD - FINAL - 7-94B - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTr
�' furnished by the contractor to the soils engineer for determination
of maximum density and optimum moisture for these materials. Tests
for this determination will be made using methods conforming to
requirements of ASTM D698. Copies of the results of these tests
will be furnished to the contractor. These test results shall be
(,•, the basis of control for compaction effort.
D E N S I T Y T E S T S
The density and moisture content of each layer of compacted fill
will be determined by the soils engineer in accordance with ASTM
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D1556 or D2167. Any material found not to comply with the minimum
specified density shall be recompacted until the required density
is obtained. The results of all density tests will be furnished to
both the owner and the contractor by the soils engineer.
4
optimum compaction. The moisture shall be uniform throughout the
fill. The contractor may be required to add necessary moisture to
the backfill material in the excavation if, in the opinion of the
soils engineer, it is not possible to obtain uniform moisture
content by adding water on the fill surface. If, in the opinion of
the soils engineer, the material proposed for use in the compaction
is too wet to permit adequate compaction, it shall be dried in an
acceptable manner prior to placement and compaction.
C O M P A C T I O N
When an acceptable uniform moisture content is obtained, each layer
shall be compacted by a method acceptable to the soils engineer and
as specified in the foregoing report as determined by the standard
Proctor test (ASTM D698). Compaction shall,be performed by rolling
with approved tamping rollers, pneumatic -tired rollers, three -wheel
power rollers, or other approved equipment well -suited to the soil
being compacted. If a sheepsfoot roller is used, it shall be
provided with cleaner bars attached in a manner which would prevent
the accumulation of material between the tamper feet. The roller
should be so designed that the effective weight can be increased.
M O I S T U R E- D E N S I T Y D E T E R M I N A T I O N
Samples of representative fill materials to be placed shall be
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P R.E P A R A T I 0 N O F S U B G R A D E
All topsoil and vegetation shall be removed to a depth satisfactory
to the soils engineer before beginning preparation of the subgrade.
The subgrade surface of the area to be filled shall be scarified
to a minimum depth of six (6) inches, moistened as necessary, and
compacted in a manner specified below for the subsequent layers of
fill. Fill shall not be placed on frozen or muddy ground.
P L A C I N G F I L L
No sod, brush or frozen material ,or other deleterious or unsuitable
material shall be placed in the fill. Distribution of material in
the fill shall be such as to preclude the formation of lenses of
material differing from the surrounding material. The materials
shall be delivered and spread on the fill surface in such a manner
as will result in a uniformly compacted fill. Prior to. compacting,
each layer shall have a maximum thickness of eight (8) inches and
its upper surface shall be relatively horizontal.
M O I S T U R E C 0 N T R 0 L
The fill material in each layer, while being compacted, shall as
nearly as practical contain the amount of moisture required for
F
APPENDIX A
Suggested Specifications for Placement of Compacted Earth Fills
and/or Backfills.
G E N E R A L
A soils engineer shall be the owner's representative to supervise
l.. and control all compacted fill and/or compacted backfill on the
project. The soils engineer shall approve all earth materials prior
to their use, the methods of placing, and the degree of compaction
obtained. A certificate of approval from the soils engineer will
be required prior to the owner's final acceptance of the filling
operations.
M A T E R I A L S
The soils used for compacted fill beneath interior floor slabs.and
backfill around foundation walls shall be impervious and non -
swelling for the depth shown on the drawings. No material shall be
placed for fill which has a maximum dimension of six (6) inches or
greater. All materials used in either compacted fill or compacted
backfill shall be subject to the approval of the soils engineer.
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FOUN OAT I O N ENGINEERING
SUMMARY OF LABORATnRY TEST RESULTS
Atterberg Limits
Unconfined
Compressive
Standard
Penetration
Soil or
Sample Location
Natural
Natural
Gradation
Percent
Passing
Hole
Depth
Naturale
Dry Density
Gravel
Sand
No. 200
Liquid
Plasticity
Strength
Blows/Ft.
Bedrock Type
(Feet)
Content (S)
PCP ).
(z)
(z)
Sieve
Limit
Inoex
* (PSF)
4
2-3
---
4
3-4
1/12
4
7-8
24.3
5/12
Clayey sand
5
2-3
20.3
101.3
---
Clayey sand
5
3-4
19.5
12/12
Clayey.sand
5
7-8
---
6/12
Clayey sand
6
1-3
23.7
21
34
45
30
12
---
7
1-3
17.1
---
8
1-3
---
Borrow
(R-val
e = 39)
i
c
*Based on Pocket Penetrometer I
FOUNOAT 10 N ENGINEERING
SUMMARY OF LABORATnRY TEST RESULTS
Sample Location
Natural
Natural
Gradation
Percent
g Passin
Atterberg Limits
Unconfined
Compressive
Standard
Penetration
Soil or
Note
Depth
Moisture
Dry Densit
(PCF).
Gravel
Sand
No. 200
Liquid
Plasticity
Strength
Blows/Ft.
Bedrock Type
(Feet)
Content (%)
(X)
(X)
Sieve
Limit
Inoex
* (PSF)
1
2-3
(R-value
= 13)
---
1
3-4
7.3
26/12
Fill
1
7-8
14.1
9/12
Clayey sand
1
14-15
24.0
8/12
Sandy clay
2
2-3
17.9
9,000+
14/12
Fill
2
7-8
12.9
128.8
16
53
31
---
Clayey sand, fil
2
8-9
15.7
12/12
Clayey sand, fil
2
14-15
22.4
9/12
Clayey sand
3
2-3
24.4
3/12
Clayey sand
3
7-8
---
3
8-9
---
i
3
14-15
8/12
*Based on Pocket Penetrometer
SWELL-CONSOLIOATION
LOAD (PSF)
500 1000 5000
Saturated at constant
pressure
V' 4
2
0
v
2
Z
C
4
Q
G
J
0 6
z
0
U
10000
SAMPLE OF FROM TEST HOLE NO. 5
7
AT DEPTH OF 2-� FEET NATURAL MOISTURE CONTENT 20.3 / NATURAL DRY DENSITY IoL3 PCF
-- —
-
J
J
l i.l
4
0
c
z
0
2
0
z
0
m
z
._.
z
m
2
m
A
z
z
�
G
F=
4
Q
C
J
0
6
-r_
O
SWELL-CONSOLIOATION
LOAD (PSF)
500 1000 5000 10000
Saturated at constant
pressure
m SAMPLE OF ;,) FROM TEST HOLE NO.. 4--
AT DEPTH OF Z-; FEET NATURAL MOISTURE CONTENT ,} NATURAL DRY DENSITY Oj(.,S PCF
0
Ln
m
0
C
Z
O
O
Z
m
Z
m
m
A
Z
`n 4
2
0
v
2
SWE L L-CON SOL I OAT ION
LOAD (PSF)
500 1000 5000 10000
Saturated at constant
pressure
SAMPLE OF FROM TEST HOLE NO. Z
c�
AT DEPTH OF ?_t�> FEET NATURAL MOISTURE CONTENT I2 NATURAL DRY DENSITY �zg.� PCF
n CD
O N
3 r+
3 O
.4
Date March 9, 1994
Commission No. 1113-05-01-01
BORING.
LOGS
-
i-1 1;AL4 If
I - G
qo-
..
. Gu:wf x( Aw.
r
gv-
9,
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-T
FOUNDATION
ENGINEER!NG FIG.4
Date March 9, 1994
Commission ni
BORING- LOGS
to
lz
Ct
L. _
177
FOUNDATION ENGINEERING
FIG- 3
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Date March 9, 1994
Commission No. 1113-05-01-01
LEGEND
OF SOI LS SYMBOLS
FILL
GRAVELS
SANDS
SHELBY TUBE SAMPLE
SILTS
GRAVELS, SAND &
SILT COMBINATIONS
STANDARD
PENETRATION
SANDY GRAVELS,
TEST
SAMPLER=
GRAVELLY SANDS
SILTY SANDS,
SANDY SILTS
SANDY CLAYS,
WATER TABLE AT
CLAYEY SANDS
TIME OF DRILLING
SAND, SILT & CLAY
COMBINATIONS
CLAYS
_
HOLE CAVED
WEATHERED BEDROCK
SILTSTONE
CLAYSTONE # 20112 indicates that 20 blows
of a 140 lb. hammer falling
SANDSTOfJE 30" was required to penetrate
12"
LIMESTONE
GRANITE
Date: March 9, 1994
BORING LOCATION MAP
FIG. 1
partly on our understanding of the characteristics of the structure
proposed, and partly on our experience with subsurface conditions
in the area. We do not guarantee the performance of the project in
1..•• any respect, only that our engineering work and judgments rendered
meet the standard of care of our profession.
I,
The test holes drilled were spaced to obtain a reasonably accurate
picture of subsurface conditions for design purposes. These
variations are sometimes sufficient to necessitate modifications
in design.
We recommend that construction be continuously observed by a
qualified soils technician trained and experienced in the field to
take advantage of all opportunities to recognize. some undetected
condition which might affect the performance of the foundation
systems.
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Northbrook Court Northbrook Drive
(DTN = 5, 18k ESAL = 36,500, o psi = 2.5, Reliability Factor = 70%,
Design Structural Number = 1.07 to 1.67)
Option 1 Option 2
HBP 3" 5"
ABC 4" --
TOTALS 7" 5"
All Hot Bituminous Pavement (HBP) shall meet Grading C (SC Type 2)
or CX (SC Type 1) or equivalent of CDOT Standards. All Aggregate
Base Course (ABC) shall meet Class 5 or 6 of CDOT Standards and be
compacted to at least 95% of standard Proctor. The subgrade shall
be stripped of vegetation and topsoil, scarified to a depth of six
(6) inches, and recompacted to at least 95% of standard Proctor at
plus or minus two percent (+2%) of optimum moisture content. The
City of Fort Collins will require a proof roll prior to placement
of pavement materials. Additional stabilization of the subgrade may
be required at this time. Stabilization techniques such as lime,
fly -ash, cement or fabric can be recommended at a later date, if
needed.
G E N E R A L I N F O R M A T I O N
The data presented herein were collected to help develop designs
and cost estimates for this project. Professional judgments on
design alternatives and criteria are presented in this report.
These are based on evaluation of technical information gathered,
15
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are to be paved. A substantial amount of fill material is to be
located underneath the roadways at the central, east and north
sides. R-value tests were conducted on the existing fill materials
along the west side and from a stockpile at Swallow Road and Dunbar
Avenue. It appears that Northbrook Court is located over existing
fill materials. It is not known if the fill material has been
compacted, tested or approved for supporting the roadways. We
recommend that the fill be evaluated by means of test pits and
compaction tests to determine the suitability of this fill for
structural, use. Ifthis is not done, we recommend that five (5)
feet of the fill be removed and recompacted to acceptable stan-
dards. The pavement will be designed for the R-value of the replace
material, either imported or on -site. The, recommendations are made
in accordance with Design Criteria and Standards for Streets - City
of Fort Collins.
Test results conducted by A.G. Wassenaar in Denver, Colorado
indicate R-values of 13 for the on -site fill and 39 for the
imported fill.
R-value of subgrade soils:
On -site fill - west side = 13 (MR) = 8215
Imported - Swallow and Dunbar = 39 (MR) = 22,645
Design Life = 20 years
Standard Deviation = 0.44
Structural Coefficients
Asphalt (HBP) = 0.44
Aggregate Base Course (ABC) = 0.11
14
(85%) to ninety percent (90%) of Standard Proctor Density as
determined by ASTM Standard Test D-698. The backfill should be
mechanically compacted in loose lifts not to exceed twelve (12)
(..; inches. Expansive soils and/or bedrock fragments should not be used
for backfill materials. If imported material is used, the soil
should be relatively impervious and non -expansive. The foundation
I_ walls should be well -cured, braced or subfloor installed prior to
backfilling. Past experience has shown that severe damage could
occur to the foundation walls if expansive material is placed for
backfill and allowed to become wet.
The backfill placed immediately adjacent to the foundation walls,
if not properly compacted, can be expected to settle with resulting
damage to sidewalks, driveway aprons, and other exterior slabs -on -
grade. To avoid settlement and disfigurement of the slabs in the
event that the backfill is not properly compacted, we recommend
that concrete slabs which must span the backfill be supported by
the foundation walls. This is conventionally done by use of a brick
ledge or haunch. Exterior slabs could be dowelled to the foundation
wall. The slab should be reinforced as necessary for the span
involved.
PAVEMENT RECOMMENDAT ION S
It is our understanding that the interior roadways for the project
13
Density ASTM D-698778.
L A N D S C A P I N G A N D D R A I N A G E
Every precaution should be taken to prevent wetting of the subsoils
and percolation of water down along the foundation elements.
Finished grade should be sloped away from the structure on all
sides to give positive drainage. A minimum of twelve (12) inches
fall in the first ten (10) feet is recommended. Sprinkling systems
should not be installed within ten (10) feet of the structure.
Downspouts are recommended and should be arranged to carry drainage
from the roof at least five (5) feet beyond the foundation walls.
Plantings are not recommended around the perimeter of the founda-
tions. However, if the owners are willing to accept the risks of
foundation and slab movement, low water use plant varieties could
be used. A horizontal impervious membrane, such as polyethylene,
should not be used next to the foundation wall. we recommend the
use of a landscape fabric which will allow normal evaporation in
lieu of a plastic membrane. All plants located next to foundations
should be hand watered only using the minimum amount of water.
Backfill around the outside perimeter of the structure, except as
noted above, should be compacted from optimum moisture to three
percent (3%) above optimum moisture, and from eighty-five percent
12
1y. Slabs on grade should be underlain with a four (4) inch layer
of clean gravel or crushed rock to help distribute floor loads and
provide a capillary break. Positive drainage should be provided
for the gravel underlayment to prevent pooling of water beneath the
slab. Exterior slabs exposed to de-icing chemicals or extreme
weathering should be constructed using a more durable concrete
containing a Type II cement with higher air contents and lower
water -cement ratios.
l:. S I T E G R A D I N G A N D U T I L I T I E S
Specifications pertaining to site grading are included below and
in Appendix A of this report. It is recommended that the upper ten
(10) inches of topsoil below building, filled and paved areas be
stripped and stockpiled for reuse in planted areas. The upper six
(6) inches of the subgrade below paved and filled areas should be
scarified and recompacted plus or minus two percent (+2%) of
optimum moisture to at least ninety-five percent (95%) of Standard
Proctor Density ASTM D-698-78 (See Appendix A of this report).
Additional fill should consist of the onsite clayey soil or
imported materials approved by the geotechnical engineer. Fill
should be placed in uniform six to eight (6-8) inch lifts and
mechanically compacted plus or minus two percent (+2%) of optimum
moisture to at least ninety-five percent (95%) of Standard Proctor
11
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to discharge all flow from the sump a minimum of five (5) feet
beyond the backfill zone.
6i
A subdrain system is recommended where future. groundwater. levels
( will be located within five (5) feet of the pavement surface or
where finished floors will be located within three (3) feet of the
groundwater. The subdrain should be designed to maintain four (4)
feet of clearance between the top of the pavement and to provide
discharge locations for perimeter drain systems. It is not known
if an adequate discharge location exists for a subdrain system at
this site. Further engineering will be needed to determine the
feasibility of the-subdrain system.
F L O O R S L A B S
Soils at proposed foundation elevations are stable at their natural
moisture condition. However, should moisture contents of the soils
increase, slight vertical movement could result, particularly at
basement elevations. This phenomenon can result in cracking of the
garage slabs or other slabs -on -grade. With the above in mind,
construction of the structure, as much as possible, should be done
to accommodate movement of.the slabs without damage.
Slabs should be constructed "free floating", isolated from all
bearing members, reinforced with wire mesh, and jointed frequent-
10
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1.
BASEMENTS AND SUBDRAINS
Basement construction is not feasible at lower areas of this site.
We understand that a substantial amount of fill material is to be
imported and placed in the lower portions of the subdivision. All
future fill materials should be placed, tested, and approved for
structural use (See Appendix A). Where basement or other habitable
lower levels are located within three (3) feet of the groundwater,
we recommend that such lower levels be provided with a perimeter
drainage system. The drainage system should contain a four (4) inch
diameter perforated drain pipe encased in a minimum of twelve (12)
inches of clean, 314 inch gravel graded in accordance with ASTM C
33-78. The drain pipe should extend around the lower level .with the
invert being placed a minimum of four (4) inches below the bottom
of the footing to facilitate moisture transfer to the perimeter
drain system. The gravel should be placed a minimum of eight (8)
inches over the pipe the full width of the trench. The whole system
should then be covered with untreated building paper or geotextile
to minimize clogging of the gravel with the backfill material.
The above drain system should be run at 118 inch per foot minimum
to either a sump constructed in the basement or "daylighted" well
beyond the foundation system. The sump should be a minimum of
eighteen (18) inches diameter by three (3) feet deep and surrounded
by at least six (6) inches of clean gravel similar to that provided
around the drain. The sump should be provided with a pump designed
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2. Foundation walls should be reinforced with rebar to span an
unsupported length of ten (10) feet or between each pad. Rebar
should be run continuously around corners and be properly
spliced. Foundations should be designed by a Registered
Engineer for the conditions described in this report.
3. it is our opinion that basement construction is feasible for
this site. However, all finished floor slabs located within
I
three (3) feet of the groundwater should be protected by a
perimeter drain as detailed in this report.
4. All footings, pads, and/or grade beams should bear on similar
strata.
5. We recommend the performance of an excavation inspection for
each lot to make a final determination on foundation type.
The foundation walls and other structural elements should be
designed by a qualified structural engineer for the appropriate
loading conditions. All footings or pads should be placed below any
topsoil or fill unless the fill has specifically been placed and
compacted for support of footings or pads. All exterior footings,
pads, and grade beams should be placed below frost depth (thirty
(30) inches in this area) to provide adequate cover for frost
protection.
I
beams should be placed on the natural, undisturbed soils. The
footings should be designed for a maximum allowable bearing
capacity of 1000 pounds per square foot (dead load plus 112 live
Lload). Where footings are expected to bear on the fill materials,
the fill should be evaluated under each structure. All fill located
under footings should be compacted to at least 95% or standard
Proctor. Footings placed on the approved fill materials should be
designed as described above.
if isolated areas of loose or soft soils are exposed during final
footing excavation, these soil areas should be removed down to
undisturbed, acceptable soils prior to placement of the footings.
Footings can then be placed directly upon the acceptable soil, or
the excavation can be backfilled up to the desired footing bearing
elevation. All fill should be placed and compacted in accordance
with the recommendations contained in the Section "Site Grading and
Utilities", and Appendix A of this report.
The following recommendations should be followed in the design of
the foundation system:
1. All footings, pads, and\or grade beams should be below frost
depth. Frost depth in this area is considered to be thirty
(30) inches.
7
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surface where fills are not found. The upper six (6) to ten (10)
( inches contain topsoil materials, laboratory and field tests
1_
indicate that these deposits exhibit very low to low bearing
capacities with no swell potential. The.sands were encountered to
the depths explored.
Groundwater observations were made as the borings were being
advanced, immediately after completion, and twenty-four hours after
the drilling operation. At the time of our field investigation,
groundwater was encountered in all deeper test holes at depths
ranging from three and one-half (3-112) feet to twelve and one-half
(12-112) feet. The groundwater table can be expected to fluctuate
throughout the year depending upon variations in precipitation,
surface irrigation and runoff on the site. The ambient groundwater
table at the site is at a level which would affect the construction
or utilization of a residence constructed over a basement and the
installation of underground utilities.
F O U N D A T I O N R E C O M M E N D A T I O N S
Spread Footings
Based upon conditions observed in the field, laboratory tests and
the anticipated loading of the structures, we feel that the
structures should be supported by a continuous balanced spread
footing and/or grade beam foundations. The footings and/or grade
6
As part of the testing program, Atterberg Limits and gradation
((� analysis were conducted on selected samples to determine the
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plasticity and texture of the soils. Two (2) R-values were
L, determined of the roadway subgrade materials for the pavement
thickness design.
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S U B S U R F A C E C O N D I T I O N S
Generally, fill materials occupy the west side and parts of the
south side of the project. Clayey sands underlie the fills on the
surface to the depths explored. Free groundwater was encountered
at relatively shallow levels where fill materials are not found.
The west side and a portion of the south edge are overlain with
fill materials. The fill is comprised of clayey, slightly gravelly
sands. The fill appears to be moderately tight. However, it is not
known if the fill has been compacted, tested, or approved for
structural use. Therefore, the fill material should not be used to
support any structures unless documentation and/or further testing
are obtained. The fill should then be evaluated on a case -by -case
basis for each structure if the fill is to be considered for
structural use.
Sands containing moderate to high amounts of clay and traces of
gravel were encountered underneath the fill materials and below the
9
L A B O R A T O R Y T E S T I N G P R O C E D U R E S
The recovered samples were tested in the laboratory to measure
their dry unit weights, natural water contents, and for classifica-
tion purposes. Selected samples were tested for strength and
stability characteristics. These include swelling, compressibility,
collapse and shear strength of the soil and/or rock.
One dimensional consolidation -swell tests were performed on
selected samples to evaluate the expansive, compressive and
collapsing nature of the soils and/or bedrock. stratum. In the
consolidation -swell test, a trimmed specimen is placed in a one-
dimensional confinement ring and a vertical load is applied. After
seating, the sample is inundated with water and the height change
of the specimen is recorded. The confining load is then incremen-
tally increased until the specimen is compressed to its original
volume. Results of :those tests are presented at the end of this
report.
A calibrated hand penetrometer was used to estimate the approximate
unconfined compressive strength of selected samples. The calibra-
ted hand penetrometer has been correlated with unconfined compres-
sion tests and provides a better estimate of soil consistency than
visual examination alone.
4
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attached boring location map, Figure 1. The locations and eleva-
tions of the borings should be considered only to the degree
implied by the methods used to make those measurements.
Complete logs of the boring operations were compiled by a represen-
tative of our firm as the borings were advanced. The approximate
location of soil and rock contacts, free groundwater levels, and
standard penetration tests are shown on each boring log. The
transition between different strata can be and most often is
gradual.
An index of soils relative density and consistency was obtained by
use of the standard penetration test, ASTM Standard Test D-1586.
The penetration test result listed on the log is the number of
blows required to drive the two (2) inch split -spoon sampler twelve
(12) inches (or as shown) into undisturbed soil by a one hundred
and forty (140) pound hammer dropped thirty (30) inches.
Undisturbed samples for use in the laboratory were taken in three
(3) inch O.D. thin wall samplers (Shelby), pushed hydraulically
into the soil in accordance with ASTM D-1587. In this sampling
procedure, a seamless steel tube with a beveled cutting edge is
pushed hydraulically into the ground to obtain a relatively
undisturbed sample of cohesive or moderately cohesive soil. All
samples were sealed in the field and preserved at natural moisture
content until time of test.
3
materials generated from a previous grading operation. Stockpiles
of fill material are located along the south side of the project.
The remainder of the site has a general slope to the east.
Vegetation was relatively sparse and consisted of grasses.
F I E L D I N V E S T I G A T I O N
The field investigation consisted of eight (8) borings at selected
locations on the site. Distances between borings are as indicated
on the attached test boring location map, Figure 1. The borings
were advanced using a four (4) inch diameter continuous flight
power auger. All borings were continued to hard bedrock or to
depths considered sufficient for the purposes of this report as set
forth in the scope.
The borings were laid out by Foundation & Soils Engineering, Inc.
personnel based on_a preliminary plat and site plan provided by
Stewart & Associates. Distances from the referenced features to the
boring locations, as indicated on the attached diagram, are
approximate and were made by pacing. Angles for locating the
borings were estimated. Elevations of the borings are approximate
and were obtained using a level and rod. The elevations were
referenced to an assumed elevation of one hundred (100) feet using
the centerline of Hampshire Road at the southwest corner of this
project. The approximate location of the benchmark is shown on the
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S C 0 P E
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The following report presents the results of our subsurface
Linvestigation on Northbrook Patio Homes P.U.D., Fort Collins,
( Colorado. This investigation was performed for Nebarado Construc-
tion at the request of Mr. Gary Mackey.
We understand the site is to be developed into forty-two (42)
single family residences. Construction is to be typical wood frame
type and brick veneer and as such, should generate only light
loading, on the order of 11000 to 2,000 PLF. Concentrated loads,
if any, should not exceed 15 to 20 KIPS.
The purpose of this investigation is to identify subsurface condi-
tions and to obtain test data to properly design and construct the
foundation systems and floor slabs. The conclusions and recommenda-
tions presented in this report are based upon the acquired field
and laboratory data and previous experience with similar subsurface
conditions in the area.
S I T E D E S C R I P T I O N
The site is located in southwest Fort Collins at the southeast
corner of Prospect Road and Hampshire Road. The west side of the
6.12+ acre site has approximately six (6) to eight (8) feet of fill
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TABLE OF CONTENTS
L
Letter of Transmittal
i
j Scope
1
-_. Site Description
1
Field Investigation.
2
Laboratory Testing Procedures
4
. Subsurface Conditions
5
Foundation Recommendations
6
Basement and Subdrains
9
Floor Slabs
10
- Site Grading and Utilities
11
Landscaping.and Drainage
12
Pavement Recommendations
13
General Information
14
Test Boring Location Map
Figure 1
Legend of Soil Symbols
Figure 2
Boring Logs
Figures 3 - 4
Consolidation Swell Tests
Figures 5 - 7
Summary of Test Results
Figures 8 - 9
Suggested Specifications for Placement
Appendix A
of Compacted Earth Fills and/or Backfills
1
FOUNDATION II Engineering,
AND SOILS Inc.
L: March 9, 1994
Commission No.: 1113-05-01-01
LNebarado Construction
6804 Aaron Drive.
Fort Collins, Colorado 80524
LGentlemen:
Theenclosed report presents the results of a subsurface
investigation, for Northbrook Patio Homes P.U..D., a proposed
subdivision of Fort Collins, Colorado.
In summary,, non-swe.11ing filland soils were encountered in the
borings. Although the site soils and/or rock are suitable for.
support of -the -proposed structures,-- care will be needed in both.
the desIgn:_.and -construction. of the buildings .,to- minimize the
'.-. potential,for foundation and floor slab iuovement.
The attached geotechnica.i z-epert presents the results o.f.6ur.�.
investigation, and .reco•mrresidat.io;a .concerning. design and cons•truc--
tion of the foundatlon system and support of floor slabs.
We appreciate the opportunity to be of service to you .on this
project. If. you have .any questions, please feel free to call.
Respectfully,
Thomas W. F7nley.)
'btu�8'tttt4lif!pryU//rr
Engineering Geologist,,,.
lz� :-,:•�QE P j
ti. F • 9
Review�dyby: L�fa��t ss'•:�`;
���23841
Kevin W. Patterson, "-
FOUNDATION & SOILS EC.
TWF/jlb
100 East 3rd Street • Loveland, Colorado 80537 • (303) 663-0138
iy 1
L
L
LSUBSURFACE: TNVEST?CAT10N
` 43.THBU., ,0K PW IO EOME S P .:; . D .
':iRT COLLINS, COLOJR-DO
L
`PrcTa -ed for
Nebar.ado Construction
6804 A-aron. r>r.ive
Fort Coili::::, Coloi-ado 80524
Marcie 9, 1994
Commission No.: .1113--05-01-01
Prepared By
FOUNDATION & SOILS ENGINEERING, YN—..
CONSULTING ENGINEERS
100 East Third Street
Loveland, CO 80537