HomeMy WebLinkAboutWEBERG PUD - FINAL - 76-88G - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTAnDENDUM TO REPORT
OF A
GEOTECHNICAL INVESTIGATION
FOR
PROPOSED WEBERG P.U.D.
FORT COLLINS, COLORADO
MURRAY AND STAFFORD, INC.
WHEAT RIDGE, COLORADO
PROJECT NO. 8042-89
Am
EMPIRE LABORATORIES, INC.
301 NORTH HOWES STREET
FORT COLLINS, COLORADO 80521
TABLE OF CONTENTS
Tableof Contents ..............................................
i
Letterof Transmittal ..........................................
Report.........................................................
1
AppendixA ....................................................
A-1
Test Boring Location Plan ....................................
A-2
Keyto Borings ................................................
A-3
Logof Borings ...............................................
A-4
Appendix B....................................................
B-1
Consolidation Test Data ......................................
B-2
Hveem Stabi lometer Data
B-3
.....................................
Summary of Test Results .....................................
B -4
Appendix C....................................................
C-1
Empire LaMoratories, Inc.
GEOTECHNICAL ENGINEERING & MATERIALS TESTING
June 5, 1989
Murray and Stafford, Inc.
4891 Independence Street, Suite 149
Wheat Ridge, Colorado 80033
Attention: Mr. Bob Stafford
Gentlemen:
CORPORATE OFFICE
PO BOx 503 • (303) 484 0359
301 No. Howes • Fort Collins. Colorado 80522
We are pleased to submit an addendum to our Report of a Geotechnical
Investigation prepared for the proposed Weberg Furniture Store located
on South College Avenue, Fort Collins, Colorado.
Based upon our findings in the subsurface, it is our opinion the site is
suitable for the proposed construction, providing the design criteria and
recommendations set forth in this report are met. The accompanying
report presents our findings in the subsurface and our recommendations
based upon these findings.
Very truly yours,
EMPIRE LABORATORIES C
Neil R. Sherrod
Senior Engineering Geologist
Reviewed by:
Chester C. Smith, P.E.
President
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cc: RBD, Inc. - Mr. Stan Myers
Vaught Frye Architects - Mr. Tony Hughes (3)
Weberg Enterprises - Mr. John P. Weberg
Branch Offices
P.O. Box 16859 PO Box 1135 PO Box 1744
Colorado Springs, CO 80935 Longmont. CO 80502 Greeley, CO 80632
(719) 597-21 16 (303) 776 3921 (303) 351 0460
Member of Consulting Engineers Council
P O Box 5659
Cheyenne. VVY 82003
(307) 632-9224
ADDFNDUM TO REPORT
OF A
GEOTECHNICAL INVESTIGATION
SCOPE
This report presents the results of an addendum to our geotechnical
evaluation prepared for the proposed retail furniture store located on
South College Avenue, south of Hickory House one-half mile south of
Harmony Road, Fort Collins, Colorado. The additional investigation
included test borings and laboratory testing of samples obtained from
these borings.
The objectives of this addendum were to (1) provide additional
subsurface data for the additional area of construction and (2) provide
recommendations regarding pavement thicknesses for proposed streets
and parking and driveway areas.
SITE EXPLORATION
The additional field exploration, carried out on May 30, 1989,
consisted of drilling, logging, and sampling five (5) test borings.
Fifteen (15) test borings were originally drilled at the site by Empire
Laboratories, Inc. on September 9, 1988. The test borings were located
by Empire Laboratories, Inc. from existing' property corners using
conventional chaining methods. The locations of the test borings are
shown on the Test Boring Location Plan included in Appendix A of this
report. Boring logs prepared from the field logs are shown in Appendix
A. These logs show soils encountered, location of sampling, and ground
water at the time of the exploration.
The borings were advanced with a four -inch diameter, continuous -
type, power -flight auger drill. During the drilling operations, a
geotechnical engineer from Empire Laboratories, Inc. was present and
made continuous observations of the soils encountered.
-1-
SITE LOCATION AND DESCRIPTION
The site is located at the southwest corner of South College Avenue
and Fairway Lane in south Fort Collins, Colorado. More particularly,
the site is described as the Weberg P.U.D. , situate in the Northeast 1 /4
of Section 2, Township 7 North, Range 69 West of the Sixth P.M., City
of Fort Collins, Larimer County, Colorado.
The site is currently occupied by residences and several corrals and
outbuildings. The property is located on the west side of South College
Avenue. The existing residence is a single -story frame structure
surrounded by a cyclone fence. The outbuildings and corrals are
located in the northeast corner of the property. A gravel drive
bordered by a wood fence extends from College Avenue to the residence
in the center of the site. The property is fenced and consists of
irrigated pasture land. Several small irrigation laterals are located
throughout the site. The area is currently vegetated with grass and
weeds. Several large trees are located adjacent to the existing
residence. The property slopes uniformly to the southeast and has
positive drainage in this direction.
LABORATORY TESTS AND EVALUATION
Samples obtained from the test borings were subjected to testing in
the laboratory to provide a sound basis for evaluating the physical
properties of the soils encountered. Moisture contents, dry unit
weights, unconfined compressive strengths, water soluble sulfates,
swelling potentials, and the Atterberg limits were determined. A
summary of the test results is included in Appendix B. Consolidation
and Hveem stabilometer characteristics were also determined, and curves
showing this data are included in Appendix B.
-2-
SOIL AND GROUND WATER CONDITIONS
The soil profile of the additional test borings at the site consists of
strata of materials arranged in different combinations. In order of
increasing depths, they are as follows:
(1) Silty Topsoil: The additional area tested is overlain by a six
(6) inch layer of silty topsoil. The topsoil has been penetrated
by root growth and organic matter and should not be used as a
bearing soil or as a fill and/or backfill material.
(2) Sandy Silty Clay: This stratum underlies the topsoil and
extends to the bedrock below. The silty clay is plastic,
contains varying amounts of sand and traces of gravel, is damp
to moist and exhibits generally moderate bearing characteristics.
When wetted, the clay stratum exhibits slight swell potential;
and upon loading, consolidation occurs.
(3) SiItstone- Sandstone Bedrock: The bedrock was encountered in
Borings 1 through 4 at depths of six (6) to seventeen (17) feet
below the surface and extends to greater depths. The upper
one-half (1/2) to two and one-half (2-1/2) feet of the bedrock
is highly weathered; however, the underlying sandstone
interbedded with siltstone is firm to dense and exhibits very
high bearing characteristics.
(4) Ground Water: Twenty-four hours after drilling, free ground
water was encountered in Borings 1 through 4 at the site at
depths of eight and one-half (8-1/2) to ten and one-half
(10-1 /2) feet below the surface. Water levels in this area are
subject to change due to seasonal variations and irrigation
demands on and/or adjacent to the site.
-3-
RECOMMENDATIONS AND DISCUSSION
It is our understanding the proposed furniture facility is to consist
of 35,000 square foot warehouse and 35,000 square foot showroom. The
finished first floor of the building will be placed at elevation 4997.
Fairway Lane will extend across College Avenue along the north side of
the site, and Fossil Boulevard will be constructed in a north -south
direction along the west edge of the property. Fossil Boulevard and
Fairway Lane have been classified as industrial commercial streets by the
City of Fort Collins. A parking area is planned adjacent to College
Avenue on the east side of the building, and loading, driveway and
employee parking areas are planned along the west side of the building.
Site Gradinq and Utilities
Finished subgrade below
building and
paved areas should
be placed
a minimum of three (3) feet
above existing
ground water, or
dewatering
systems should be provided
to lower ground
water levels.
All other
recommendations for site grading and utilities
set forth in our original
"Report of a Geotechnical
Investigation"
prepared for the
site dated
September 22, 1988 should
be followed
during construction of the
proposed Weberg furniture store.
In view of the loads transmitted by the proposed furniture facility
and the soil conditions encountered at the site, it is recommended that
the structure be supported by conventional -type spread footings and/or
grade beams. All footings and/or grade beams should be founded on the
original, undisturbed soil or on a structural fill extended to the
undisturbed soil. All exterior footings should be placed a minimum of
thirty (30) inches below finished grade for frost protection. The
structural fill should be constructed in accordance with the
recommendations discussed in the "Site Grading, Excavation and Utilities"
-4-
section of our original report. The structural integrity of the fill as
well as the identification and undisturbed nature of the soil should be
verified by the geotechnical engineer prior to placement of any
foundation concrete. Footings and/or grade beams founded at the above
levels may be designed for a maximum allowable bearing capacity of one
thousand five hundred (1500) pounds per square foot (dead load plus
maximum live load). To counteract swelling pressures which will develop
if the subsoils become wetted, all footings and/or grade beams should be
designed for a minimum dead load of five hundred (500) pounds per
square foot.
The predicted settlement under the above maximum loading, as
determined by laboratory consolidation tests, should be less than
three -fourths (3/4) inch, generally considered to be within acceptable
tolerances.
A feasible foundation alternate would be to support the structure by
a drilled pier foundation system. Using this type of foundation system,
the structure is supported by piers drilled into the bedrock stratum and
structural grade beams spanning the piers. Piers should be
straight -shaft and should be drilled within plumb tolerances of one and
one-half percent (1-1 /2%) relative to the length of the pier. The piers
are supported by the bedrock stratum partially through end bearing and
partially through skin friction. It is recommended that all piers have
minimum ten (10) foot lengths and that they be drilled a minimum of
three (3) feet into the firm bedrock stratum. Piers founded at the
above level may be designed for a maximum allowable end bearing
pressure of forty thousand (40,000) pounds per square foot. It is
estimated that a skin friction of four thousand (4000) pounds per square
foot will be developed for that portion of the pier embedded three (3)
feet into the firm bedrock stratum. To counteract swelling pressures
which will develop if the subsoils become wetted, all piers should be
designed for a minimum dead load of five thousand (5000) pounds per
square foot. Where this minimum dead load requirement cannot be
satisfied, it is recommended that skin friction from additional embedment
into the firm bedrock be used to resist uplift. To help provide the
required skin friction, the sides of the pier drilled into the bedrock
-5-
stratum should be roughened. All piers should be reinforced their full
length to resist tensile stresses created by swelling pressures acting on
the pier. It is recommended that all grade beams have a minimum four
(4) inch void between the bottom of the beam and the soil below. The
predicted settlement under the above maximum loading should be
negligible. All other recommendations contained in our original report
for the design and construction of the pier foundation should be
followed.
Slabs on Grade
Subgrade below slabs on grade should be prepared in accordance
with the recommendations discussed in the "Site Grading and Utilities"
section of our original report. Slabs on grade supporting heavy floor
loads in the warehouse portion of the structure should be underlain by
at least six (6) inches of crushed gravel base course, compacted at
optimum moisture to at least ninety-five percent (95$) of Standard
Proctor Density ASTM D 698-78. ( See Appendix C.) Floor areas
transmitting light floor loads should be underlain by a minimum of four
(4) inches of clean gravel or crushed rock devoid of fines. The gravel
base course and/or gravel should help to distribute floor loads and
should act as a capillary break. Slabs on grade should be designed for
the imposed loading, and it is recommended that they be designed
structurally independent of bearing members. To minimize and control
shrinkage cracks which may develop in slabs on grade, we suggest that
control joints be placed every fifteen (15) to twenty (20) feet and that
the total area contained within these joints be no greater than four
hundred (400) square feet.
In addition, if building construction is done during winter months,
it is recommended that the slab on grade not be poured until the
building has been enclosed and heat is available within the building
area so that slab -on -grade concrete is not placed on frozen ground.
This will also aid in proper curing of the slab concrete.
In addition, all recommendations for backfill, retaining wall and light
standard construction set forth in our original report should be followed.
Flexible Pavement
It is our opinion that flexible pavement is suitable for the proposed
street construction at the site. A flexible pavement alternate should
consist of asphalt concrete underlain by crushed aggregate base course
or asphalt concrete underlain by plant mix bituminous base course.
Using the City of Fort Collins "Design Criteria and Standards for
Streets" dated July 1986, a serviceability index of 2.0 for parking and
driveway areas and 2.5 for streets, a regional factor of 1, an "R" value
of 6, a twenty (20) year design life, eighteen (18) kip equivalent daily
load applications of 5 for parking areas, 10 for driveway areas, 30 for
Fossil Boulevard and 40 for Fairway Lane as provided by the City of
Fort Collins, and weighted structural numbers of 2.35 for parking areas,
2.60 for driveway areas, 3.20 for Fossil Boulevard and 3.35 for Fairway
Lane, the following minimum pavement thicknesses are recommended:
Passenger Car Parking
Asphalt Concrete 2}"
Crushed Aggregate Base Course 11"
Total Pavement Thickness 13111
Asphalt Concrete 21"
Crushed Aggregate Base Course 4"
Select Subbase 8"
Total Pavement Thickness 141"
Asphalt Concrete 3"
Plant Mix Bituminous Base Course 44"
Total Pavement Thickness 7}"
Driveways and Truck Loading Areas
Asphalt Concrete 3"
Crushed Aggregate Base Course 12"
Total Pavement Thickness 15"
-7-
Asphalt Concrete 3"
Crushed Aggregate Base Course 6"
Select Subbase 6"
Total Pavement Thickness 15"
Asphalt Concrete 2"
Plant Mix Bituminous Base Course 5"
Total Pavement Thickness 7"
Fossil Boulevard
Asphalt Concrete 4"
Crushed Aggregate Base Course 13"
Total Pavement Thickness 17"
Asphalt Concrete 4"
Crushed Aggregate Base Course 6"
Select Subbase 811
Total Pavement Thickness 18"
Asphalt Concrete 211
Plant Mix Bituminous Base Course 7"
Total Pavement Thickness 9"
Fairway Lane
Asphalt Concrete 4"
Crushed Aggregate Base Course 15"
Total Pavement Thickness 19"
Asphalt Concrete 4"
Crushed Aggregate Base Course 6"
Select Subbase 10"
Total Pavement Thickness 20"
lu
Asphalt Concrete 211
Plant Mix Bituminous Base Course 7}"
Total Pavement Thickness 94"
The select subbase should meet City of Fort Collins Class 1 specifications,
and the crushed aggregate base course should meet City of Fort Collins
Class 5 or 6 specifications. The subgrade below the proposed asphalt
pavement should be prepared in accordance with the recommendations
discussed in the "Site Grading and Utilities" section of the original
report. Finished subgrade below building and paved areas should be
placed a minimum of three (3) feet above existing ground water, or a
dewatering system should be provided to lower water levels. Upon
proper preparation of the subgrade, the subbase and base course should
be placed and compacted at optimum moisture to at least ninety-five
percent (950) of Standard Proctor Density ASTM D 698-78. (See
Appendix C. )
It is recommended that the asphalt concrete and/or plant mix
bituminous base course be placed in two (2) to three (3) inch lifts. All
plant mix bituminous base course and asphalt concrete shall meet City of
Fort Collins specifications and should be placed in accordance with these
specifications. All subbase material shall have an "R" value between 50
and 69, the crushed aggregate base course shall have an "R" value
between 70 and 77, the plant mix bituminous base course shall have an Rt
value of 90 or greater, and the asphalt concrete shall have an Rt value of
95 or greater. The "R" value of the pavement materials used should be
verified by laboratory tests. Field density tests should be taken in the
aggregate base course, bituminous base course, and asphalt concrete
under the direction of the geotechnical engineer.
Rigid Pavement
A feasible pavement alternate at the site would be rigid pavement.
Using the eighteen (18) kip equivalent daily load application described
above, a modulus of subgrade reaction of one hundred (100) pounds per
square inch per inch based on an "R" value of 6, a design life of twenty
(20) years, and concrete designed with a modulus of rupture of six
hundred (600) pounds per square inch, the following minimum pavement
thicknesses are recommended:
Passenger Car Parking and Driveway Areas
Nonreinforced Concrete - S"
Fossil Boulevard and Fairway Lane
Nonreinforced Concrete - 6"
Subgrade below proposed streets should be prepared in accordance with
the recommendations discussed in the "Site Grading and Utilities" section
of our original report. Concrete pavement should be placed directly on
the subgrade that has been uniformly and properly prepared in
accordance with the above recommendations. All concrete used in the
paving shall meet ASTM specifications, and all aggregate shall conform to
ASTM C-33 specifications. The concrete should be designed with a
minimum modulus of rupture of six hundred (600) pounds per square
inch in twenty-eight (28) days. It is recommended that laboratory mix
designs be done to determine the proper proportions of aggregates,
cement, and water necessary to meet these requirements. It is essential
that the concrete have a low water -cement ratio, an adequate cement
factor, and sufficient quantities of entrained air. Joints should be
carefully designed and constructed in accordance with the City of Fort
Collins "Design Criteria and Standards for Streets" to ensure good
performance of the pavement. It is recommended that all concrete
pavement be placed in accordance with City of Fort Collins
specifications. If paving is done during cold weather, acceptable cold
weather procedures as outlined in the City specifications should be
utilized. The concrete pavement should be properly cured and protected
in accordance with the above specifications. Concrete injured by frost
should be removed and replaced. It is recommended that the pavement
not be opened to traffic until a flexural strength of four hundred (400)
-10-
pounds per square inch is obtained or a minimum of fourteen (14) days
after the concrete has been placed.
GENERAL RECOMMENDATIONS AND COMMENTS
All general recommendations and general comments set forth in our
original report should be followed.
APPENDIX A.
El
TEST BORING ' LOCATION PLAN
• 1a
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21 L� • u.
A-2
EMPIRE LABORATORIES. INC
•
KEY TO BORING LOGS
'77
L� �,
TOPSOIL
U
GRAVEL
®
FILL
SAND & GRAVEL
SILT
:��
��
SILTY SAND & GRAVEL
CLAYEY SILT
ov o
COBBLES
i�
SANDY SILT
-
:
SAND, GRAVEL & COBBLES
®
CLAY
WEATHERED BEDROCK
SILTY CLAY
= _
®
SILTSTONE BEDROCK
SANDY CLAY
®
CLAYSTONE BEDROCK
aSAND
SANDSTONE BEDROCK
SILTY SAND
®
LIMESTONE
CLAYEY SAND
"_LLIJ ■ xGRANITE
P..
SANDY SILTY
CLAY ❑
'
SHELBY TUBE SAMPLE
STANDARD PENETRATION DRIVE SAMPLER
WATER TABLE
24 HRS. AFTER DRILLING
C
HOLE CAVED
5/12 Indicates
that 5 blows of a 140 pound hammer falling
30 inches was required to penetrate 12 inches.
A-3
LOG Of BOW NGS
_I ELEVfk,TION .NL Na.2 No
95
90
tl
75
F
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EMPIRE IAIORATORIM INC.
•
LOG Of BMNGS
E L E VATION _ N� No 5
100
95
90
a
75
70
A-5
LMPIRG LAIQRATORIM INC,
A-5
LMPIRG LAIQRATORIM INC,
APPENDIX B.
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SWILL - CONSOLIDATION TEST F F, 0 . c-1, 0 4 2
PC'PlHG 1-10. : 4
DEPTH: "I . 0
DP,( DEHc;lT,,,: 1 10.8 PCF
1101STI-IRE: %
0.25 0.5 1.0
APPLIED PRESSURE — TSF
bw
1IRTER RDDED
0.1 0.25 0.5 1.0
APPLIED PRESSURE — TSF
EHPIRE LRBORATOPIES IHC.
B-2
RESISTHNCE R-VALUE AND EXPRNSION PRESSURE
OF COMPACTED SOIL
ASTM - D 2844
CLIENT: HURRAY & STRTFORD
PROJECT: WEBER..G P.U.D.
LOCATION OF SAMPLE: BORING NO. 5 @ 0.5'-4.0'
SAMPLE DATA
l t5 i 5rtU i NEN
1
2
COMPACTION PRESSURE
- PSI
0
0
DENSITY - PCF
102.5
98.7
MOISTURE - %
22.8
26.6
EXPANSION PRESSURE
- PSI
0.00
0.00
HORIZOt4TAL PRESSURE
@ 160 psi
142
148
SAMPLE HEIGHT - in.
2.47
2.50
E:;UDATIOtl PRESSURE
- PSI
318
159
Ut1CORRECTED R-VALUE
6.7
4.3
CORRECTED R-VALUE
6.7
4.3
R-VALUE AT 300 PSI
EXUDATION
PRESSURE =
6.3
1013
-
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Q� 40
20
3
60
104.4
19.8
0.00
135
2.53
477
9.9
9.9
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APPENDIX C.
APPENDIX C.
Suggested Minimum Specifications for Placement of Compacted
Earth Fill and/or Backfills
GENERAL
The geotechnical engineer shall be the owner's, architect's,
engineer's or contractor's representative to observe placement of
compacted fill and/or backfill on the project. The geotechnical engineer
or his representative shall approve all earth materials prior to their use,
the method of placement and the degree of compaction.
MATERIALS
Soils used for all compacted fill and backfill shall be approved by
the geotechnical engineer or his representative prior to their use. Fill
material shall be free from organic matter, frozen material and other
unsuitable substance and shall not contain rocks or lumps having a
diameter greater than six (6) inches.
SUBGRADE PREPARATION
All topsoil,
vegetation, trees, brush, timber, debris, rubbish and all
other unsuitable
material shall be removed to a depth satisfactory to the
geotechnical engineer or his representative. The material shall be
disposed of by
suitable means prior to beginning preparation of the
subgrade. The
subgrade shall be scarified a minimum depth of six (6)
inches, moisture
conditioned as necessary and compacted in a suitable
manner prior to
placement of fill material. Fill shall not be placed until
approval by the
geotechnical engineer or his representative; and in no
case, shall fill
material be placed on frozen or unstable ground.
Subgrade which
is not stable may require the use of imported granular
material, geotextiles
or other methods for stabilization as approved by the
geotechnical engineer.
FILL PLACEMENT
Fill material shall not
be placed during unfavorable weather
conditions. Material
proposed
for use as fill shall be
approved by the
geotechnical engineer
or his representative prior to use.
Proposed import
material shall be
approved
by the geotechnical
engineer or his
representative prior
to hauling
to the project site. Fill
material shall be
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uniformly mixed such as to preclude the formation of lenses of material
differing from the surrounding material. All clods shall be broken Into
small pieces. The contractor shall construct the fill in approximately
horizontal lifts extending the entire length of the fill. The thickness of
the layers before compaction shall not be greater than eight (8) Inches.
Fill being placed on slopes or hillsides shall be benched Into the existing
slope. A minimum two (2) foot horizontal bench shall be cut into the
existing excavated slope for each four (4) feet vertical of fill, or each lift
should be benched slightly into the existing grade.
MOISTURE CONTROL
Prior to and during compaction operations, the fill material being
placed shall be maintained within the range of optimum moisture specified.
A general recommendation is to maintain the fill material within two
percent (2%) plus or minus of optimum moisture so that proper compaction
to the specified density may be obtained with a minimal effort. In
building pad and paved areas, material exhibiting swelling potential shall
be maintained between optimum moisture and two percent (2%) wet of
optimum moisture content. The moisture content of the fill material shall
be maintained uniform throughout the fill. The contractor may be
required to add necessary moisture to the fill material and to uniformly
mix the water with the fill material If, in the opinion of the geotechnical
engineer, it is not possible to obtain uniform moisture content by adding
water on the fill surface. If, in the opinion of the geotechnical engineer,
the material proposed for use in the compacted fill is too wet to permit
adequate compaction, it shall be dried in an acceptable manner prior to
placement and compaction. Uniform mixing may require discing, blading
or other methods approved by the geotechnical engineer or his
representative.
Adjustments of moisture content shall be made on the basis of
determinations of moisture content by field tests as construction
progresses.
COMPACTION
The contractor shall furnish and operate the necessary types and
kinds of equipment to perform the operations required to obtain the
specified compaction. This equipment may include approved tamping
rollers, rubber tired rollers, smooth wheeled rollers and vibratory
rollers. If a sheepsfoot roller is used, it shall be provided with cleaner
bars so attached as to prevent the accumulation of material between the
tamper feet. Fill areas which are not accessible to full-sized construction
equipment shall be placed in maximum four (4) Inch lifts and compacted
with power tampers to the specified density.
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Compaction should meet the minimum percentages of maximum density
as set forth in the project specifications or the recommendations of the
report. The contract specifications supercede the recommendations given
in this report.
MOISTURE DENSITY RELATIONSHIP DETERMINATION
Samples of representative fill materials to be placed shall be
furnished by the contractor to the geotechnical engineer for determination
of maximum density and optimum moisture or relative density. Sufficient
laboratory moisture density or relative density curves will be made to
determine the optimum moisture content and maximum density for the
various soils placed as fill. Tests for this determination will be made
using the apbropriate method conforming to the requirements of ASTM D
698 (Standard Proctor), ASTM D 1557 (Modified Proctor) or ASTM D 4253,
D 4254 (Relative Density). The materials used for fill shall be classified
in accordance with ASTM D 2487 in order to permit correlation between
the moisture density relationship data and the material being placed and
compacted. Copies of the results of these tests will be furnished to the
client and others as directed by the client. These test results shall be
the basis of control for all compaction effort.
FIELD DENSITY AND MOISTURE TESTS
The in -place density and moisture content of compacted fill will be
determined by the geotechnical engineer or his representative in
accordance with ASTM D 1556 (sand cone method) or ASTM D 2922, D
3017 (nuclear methods). Material not meeting the required compaction
and/or moisture specifications shall be recompacted and/or moisture
conditioned until the required percent compaction and/or moisture content
is obtained. Sufficient compaction tests shall be made and submitted to
support the geotechnical engineer's or his representative's
recommendations. The results of density tests will also be furnished to
the client and others as directed.
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