HomeMy WebLinkAboutSoil Investigation Investigation - PLN General - 8/6/1996 GEOTECHNICAL
T I4ST I NC LABORATORY
Thomas Swidecki
381 Dartmoor
Shelton, WA 98584
Re: Subsurface Soils Investigation
for a garage
Gentlemen:
In compliance with your instructions, we have conducted a soils exploration and foundation
evaluation for the above mentioned addition. The results of this investigation, together with our
recommendations, are to be found in the following report. We have provided three copies for
your review and distribution.
During our exploration, three density tests and two borings were advanced and soil samples
submitted for laboratory testing from the project site. The data has been carefully analyzed to
determine soils bearing capacities and footing embedment depths. The results of the exploration
and analysis indicate that conventional spread and continuous wall footings appear to be the
most suitable type of foundation for the support of the proposed structures. Some variability
was encountered in comparing the soil profiles of the site. Net allowable soil pressures,
embedment depth, and total expected settlements have been presented for the site, later in the
report.
If you have any questions concerning the test results, the procedures used,or if we can be of any
further assistance please call on us at(360) 754-4612.
Respectfully Submitted,
GEOTECHNICAL TESTING LABORATORY
Harold Parks
Engineering Geologist
10011 Blomberg Street SW,Olympia,WA 98512
Phone#:(360)7544612 Fax#:(360)7544848
SOILS
INVESTIGATION
REPORT
381 DARTMOOR
Prepared For:
Thomas Swidecki
Shelton, WA
By:
Geotechnical Testing Laboratory
8-6-96
GEOTECHNICAL
TESTING LABORATORY
DISCRIPTION
The purpose of this section is to enumerate details of the proposed structure. The following information was provided
by the home owner. The building will be a one story wood garage structure. No basements are planned.
Conventional spread footings and slab-on-grade floors are contemplated. Differential settlements are limited to 3/4
inch. Loads of 2,000 pounds per lineal foot for wall footings and 80,000 pounds for columns were assumed for
settlement calculations.
FOUNDATION DISCUSSION AND RECOMMENDATIONS
General Notes:
Various foundation types have been considered for the support of the proposed building structure. Two requirements
must be fulfilled in the design of foundations. First, the load must be less than the ultimate bearing capacity of the
foundation soils to maintain stability; and secondly, the differential settlement must not exceed an amount that will
produce adverse behavior of the superstructure. The allowable settlement is usually exceeded before bearing capacity
considerations become important; thus, the allowable bearing pressure is normally controlled by settlement
considerations.
Considering the subsurface conditions and the proposed construction, it is recommended that the structure be
founded upon conventional spread and continuous wall footing foundations. Settlements should not exceed tolerable
limits if the following design and construction recommendations are observed.
Foundation Design Recommendations:
On the basis of the data obtained from the site and the test results from the various laboratory tests performed,
GEOTECHNICAL TESTING LAB recommends that the following guidelines be used for the net allowable soils
bearing capacity.
Net Allowable
Footing ASTM D 1557 Soils Bearing
Depth Subgrade Compaction Capacity
surface 90% 1,500 lbs./112
12 inches 90% 2,000 lbs./ft2
The footings should be proportioned to meet the stated bearing capacity and/or the Uniform Building Code 1994
minimum requirements. Total settlement should be limited to 1 inch total with differential settlement of 3/4 inch.
Any excessively loose or soft spots or areas that do not meet the compaction requirements that are encountered in the
footing subgrade will require over-excavation and backfilling with at least 2 feet of structural fill. In order to
minimize the effects of any slight differential movement that may occur due to variations in the characters of the
supporting soils and any variations in seasonal moisture contents, it is recommended that all continuous footings be
suitably reinforced to make them as rigid as possible.
10011 Blomberg Street SW,Olympia,WA 98512
Phone#: (360)754-4612 Fax#: (360)754-4848
G EOTECHNICAL
TESTING LABORATORY
Re: In-Place Density Test Report performed on 8-6-96
Project: Garage
Inspector: H. Parks
Gentlemen:
As requested Geotechnical Testing Laboratory performed on-site density testing in accordance with current applicable
standards. The results obtained were as follows:
Test Location Percent Dry Material Percent
# Moisture Density Type Compaction
1 foundation area 7.5 130.2 A 97
2 7.4 128.7 96
3 7.1 127.5 95
4
5
Required Compaction: 90%
Material Type: Gravel Fill
A: 133.8 @ 12.8% 134.5 Rock Correction
10011 Blomberg Street SW, Olympia, WA 98512
Phone#: (206)754-4612 Fax#: (206)754-4848
GEOTECHNICAL
TESTING LABORATORY
MOISTURE DENSITY
RELATIONSHIP
Source: On-site
Date Obtained: 8-7-96
Sample ID: A
ASTM D 2487 Classification: Gravel
Sample Prepared: Moist: X Manual:
Dry: Mechanical: X
Test Standard: AASHTO T 99: AASHTO T 180: Medwd
ASTM D 698: ASTM D 1557: X A
Assumed Point Percent Dry Maximum Optimum% Sieve Percent Sample
Sp.Gr. Number Moisture Density Dry Density Moisture Size Passing Specs
2.34 1 8.8 126.1 133.8 Ibs/ft^3 12.8% 3.0"
2 10.4 130.8 1.5"
3 12.2 133.8 ASTM D4718,Correction for Oversize Particles 1.25"
4 14.3 132.5 134.5 Ibs/ft^3 1.0"
7/8"
3/4" 93
Moisture Density Curve 5/8"
1/2"
135.0 3/8"
1/4"
133.0 #4
#8
131.0 410
Dry Density #16
129.0 #20
#30
127.0 - #40
#50
125.0 #60
8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0 16.0 #80
Percent Moisture #100
#200
10011 Blomberg Street SW, Olympia, WA 98512
Phone#: (360)754-4612 Fax#: (360)754-4848