HomeMy WebLinkAboutObservation of Excavation 06.20.2019•
Kumar & Associates. lam,
Geolechnicai and Materials Engineers
and Environmental Scientists
An Employee Owned Company
5 120 County Road 154
Glenwood Springs, CO 8160 ]
phone: (9 70) 945-7988
fax: (970) 945-8454
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: Deriver (FR)), Parker, Colorado Springs, Fort Collins, Glenwood Springs. in 1 S
June 20, 2019
Design Source Build, LLC
Attn: Slawek Wojciuch
P.O. Box D
Aspen, Colorado 81612
sirlwekla)Aesig[1sourcebui] .eitIn
Subject:
Dear Slawek:
Aorado
Project No. 17-7-896
Observation of Excavation, Proposed Residence, Lot 15, Spring Ridge Reserve,
Spring View Drive, Garfield County, Colorado
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on June 14, 2019 to evaluate the soils exposed for foundation support. The findings
of our observations and recommendations for the foundation design are presented in this report.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated February 5, 2018, Project No. 17-7-896.
At the time of our visit to the site, the foundation excavation had been cut in multiple levels from
1 to 5 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of stiff, sandy silty clay. Results of swell -consolidation testing performed on samples
taken from the site, shown on Figures 1 to 3, indicate the soils have low to moderate
compressibility under loading and wetting. No expansion potential was indicated when the
samples were wetted. No free water was encountered in the excavation and the soils were moist.
The soil conditions exposed in the excavation are generally consistent with those previously
encountered on the site and suitable for support of spread footings designed for the
recommended allowable bearing pressure of 2,000 psf. Loose and disturbed soils should be
removed in the footing areas to expose the undisturbed natural soils. Other recommendations
presented in our previous report which are applicable should also be observed.
The recommendations submitted in this letter are based on our observation of the soils exposed
within the foundation excavation and the previous subsurface exploration at the site. Variations
in the subsurface conditions below the excavation could increase the risk of foundation
movement. We should be advised of any variations encountered in the excavation conditions for
possible changes to recommendations contained in this letter. Our services do not include
determining the presence, prevention or possibility of mold or other biological contaminants
Design Source Build, LLC
June 20, 2019
Page 2
(MOBC) developing in the fUture. If the client is concerned about MOBC, then a professional in
this special field of practice should be consulted.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, inc
Daniel E. Hardm, P. .•
43'. 6 '•?// /41)=.1
Rev. by: SLP
• Sr
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DEH/kac
Attachments: Figures 1 through 3 — Swell -Consolidation Test Results
Kumar & Associates, Inc. Project No. 174496
CONSOLIDATION - SWELL
Timis Wol molts 40* only 10 w
MITpM. t.it.d. Tll. l..l'wl r.p.r<
i I not ho w0rodund, Mwp4 In
lop, rphout the wMbn o Snell of
manL N
humor nod Msnvla.c- Snnl
occord do l unrnp p.rtwm.d In
occordonn ,Nlh 1511 D-4046.
SAMPLE OF: Sandy Silty Clay
FROM: Westside ® Footing Grade
WC = 14.2 %, DD = 104 pcf
ADDITIONAL COMPRESSION
UNDER CONSTANT PRESSURE
DUE TO WETTING
1
1.0 APPLIED PRESSURE - KSF 10
100
17-7-896
H-PKUMAR
SWELL -CONSOLIDATION __TES_T___RESULTS
Flg. 1
.. 0
CONSOLIDATION - SWELL
ihaep tut nada epplY on ' la Sher.
mo lepled. The teetlng espwl
»ol ee Ie wItead, eepl In
Ku r ondl the .nlltan nppn nbl of
Kana one Afo
inloe, Inc. Sec
ccMondobon letting Wormed to
xcardanca nllh autiA 13-1546.
SAMPLE OF: Sandy Silty Clay
FROM: Center 0 Footing Grade
WC = 11.0 %, DD = 115 pcf
NO MOVEMENT UPON
WETTING
APPLIED PRESSURE - KSF 10 100
17-7-896
H-P�KUMAR
SWELL -CONSOLIDATION TEST RESULTS
Fig. 2
1
.. 0
CONSOLIDATION - SWELL
—1
SAMPLE OF: Sandy Silty Clay
FROM: Southeast Corner ® Footing Grade
WC = 10.5 %, DD = 105 pcf
Theis teal notate appy only 10 Om
samples tested. The lasting upon:
shall not be ',produced, peapt In
full, without the written approval of
Kumar and hsiockthee. Inc. Sall
Consolidation teeing oerfarmed b,
accordance with OSTIA 0-4540.
ADDITIONAL COMPRESSION
UNDER CONSTANT PRESSURE
DUE TO WETTING
1.0 APPLIED PRESSURE — KSF 10 100
17-7-895
H -P- KUMAR
SWELL -CONSOLIDATION TEST RESULTS
Fig. 3
if . ;