HomeMy WebLinkAboutPOTTS PUD PRELIMINARY - 6 92 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTPRELIMINARY SUBSURFACE
SOILS INVESTIGATION
FOR
AN APARTMENT PROJECT IN
A PORTION OF MATADOR 4TH ADDITION,
FORT COLLINS, COLORADO
Prepared for
Mr. John Freeman
Architecture One, P.C.
150 East 29th Street
Palmer Gardens, Ste 200
Loveland, Colorado 80538
February 7, 1992
Commission No. 1044-04-01-01
CONSULTING ENGINEERS
I FOUNDATION & SOILS ENGINEERING, INC.
100 East Third Street
r Loveland, CO 80537
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i
FOUNDATION Engineering,
AND SOILS II Inc.
February 7, 1992
Commission No. 1044-04-01-01
Mr. John Freeman
Architecture One, P.C.
150 East 29th Street
Palmer Gardens, Ste 200
Loveland,. Colorado 80538
Dear Mr. Freeman:.
The enclosed report presents the preliminary results of a
subsurface soils investigation for a portion of Matador Fourth
Addition, located in Fort Collins, Colorado.
In summary, moderate to nonswelling plastic and granular soils and
bedrock strata were encountered in the borings. Care should be
taken during and after construction to minimize the potential. for
foundation and floor movement.
The attached geotechnical report presents the results of our
investigation and recommendations concerning design and construc-
tion of the foundation 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 call.
Respectfully,
trill
Kevin W. Patt
FOUNDATION &
KWP/sbs
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100 East 3rd Street • Loveland, Colorado 80537 • (303) 663-0138
TABLE OF CONTENTS
Letter of Transmittal i
1
Scope 2
Site Description 2
Field Investi.gati.on
Laboratory Testing Procedures 4
Subsurface Recommendations 5
Foundation Recommendations 6
Floor Slabs 9
Site Grading and utilities 11
Landscaping and Drainage 11
Preliminary Pavement Recommendations 13
General Information 14
Consolidation Swell Tests Figures 1 - 4
Test Boring Location Map Figure 5
Legend of Soil Symbols Figure 6
Boring Logs Figures 7 - 8
Suggested Specifications for Placement Appendix A
of Compacted Earth Fills and/or Backfills
S C O P E
The following report presents the preliminary results of our
subsurface soils investigation on a portion of Matador Fourth
Add.iti.on, situate in Section 15, Township 7 North, Range 69 West,
of the 6th Prime Meridian, Larimer County, Colorado. This inves-
tigation was performed for Architecture One, P.C. at the request
Of Mr. John Freeman.
We understand the site is to be developed into three (3) 6-plex and
two (2) 4-plex apartment units. Construction is to be typical wood
frame type and brick veneer and as such, should generate only light
loading, on the order of 1,000 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 develope preliminary feasibility
and cost estimates for the construction of the foundation system,
floor slabs, and parking area. The conclusions and recommendations
presented in this report are based upon the acquired field and
laboratory data and previous experience with similar subsurface
conditions in the area.
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S I T E D E S C R I P T I O N
The site is located in West Fort Collins, south of West Elizabeth
Street and Taco Bell. The Matador Apartments are located east of
the project. The Latimer County Canal borders the west and
southwest sides of the property.
Stockpiles of soil, concrete and debris were located at the west
and central portions of the site. The site appears to have been
relatively flat prior to placement of the stockpiled materials.
F I E L D I N V E S T I_G A T I 0 N
The field investigation consisted of five (5) borings at selected
locations on the site. Distances between borings are as indicated
on the attached test boring location map, Figure 4. 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.
Complete logs of the boring operation are shown on the attached
figures and include visual classifications of each soil, location
of soil changes, standard penetration test results, and water table
measurement at the time of this investigation.
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The borings were laid out by Foundation & Soils Engineering Inc.
personnel based on a site plan provided by Architecture One. `
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. The
locations of the borings should be considered only to the degree
implied by the methods used to make those measurements.
As the boring operation advanced, 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 one (1) foot into undisturbed
soil by a one hundred and forty (140) pound hammer dropped thirty
(30) inches.
Specific conditions at each boring location are indicated on each
individual boring log. The stratification boundaries shown on the
boring logs represent the approximate location of changes in soil
and rock types. In situ, the transition between the different
strata can and often is gradual.
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
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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.
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 and natural water contents. A calibrated
hand penetrometer was used to estimate the approximate unconfined
strength of selected samples. The calibrated hand penetrometer has
been correlated with unconfined compression tests and provides a
better estimate of soil consistency than visual examination alone.
One-dimensional consolidation swell tests were performed on
selected samples to evaluate the expansive nature of the natural
cohesive soils. 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 incrementally increased until the specimen is compressed
to its original volume. Results of those tests are presented in the
end of this report.
The laboratory testing program was undertaken to measure critical
shear and consolidation -swelling characteristics of the soil.
Additional testing included tests necessary to verify visual
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classification and moisture content of soils from borings.
S U B S U R F A C E C O N D I T I O N S
The subsurface conditions were relatively uniform throughout the
site. A minor to moderate amount of fill (with the exception of the
stockpiles) appears to have been placed at the north end of the
project. Underlying the fills and the surface are sandy clays over
clayey sands and gravel over a siltstone type bedrock to the depths
explored.
The stockpiles located at the site consist of sandy clays with high
amounts of organic matter and concrete. These stockpiles should not
be used for fill under buildings, slabs or pavement.
A small amount of fill was located at the north end of the project.
PLacement conditions of the fill are not known at this time.
Therefore, foundation should be placed on this fill.
Clays containing moderate amounts of sand were found below the
fills. The clays are relatively plastic, exhibiting low to moderate
bearing capacities, have a low to moderate swell potential. These
deposits range in depths of approximately three to six (3-6) feet
at the site.
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