13-0546 (SFD) Geotechnical ReportsSladden Engineering
45090 Golf Center Parkway, Suite F, Indio, CA 92201 (760) 863-0713 Fax (760) 863-0727
6782 Stanton Avenue, Suite A, Buena Park, CA 90621 (714) 523-0952 Fax (714) 523-1369
450 Egan Avenue, Beaumont, CA 92223 (951) 845-7743 Fax (951) 845-8863
800 E. Florida Avenue, Hemet, CA 92543 (951).76678777 Fax (951) 766-8778
August 9, 2013
Discovery Builders California
80955 Avenue 52
La Quinta, California 92253
Attention: Mr. Rick Miller
Project: Lippman Residence
Project No. 522-13109
13-08-388
81-663 Baffin Way
Lots 101B & 102B
Madison Club
La Quinta, California
Subject: Compaction Testing — Building Pad
Ref: Geotechnical Update prepared by Sladden Engineering dated May 10, 2013; Project
No. 544-13109, Report No. 13-05-168
Summarized in this report are the results of in-place density testing performed at the subject site
as requested. Testing was performed subsequent to the fine grading of the previously rough
graded building pad. The project site is located at 81-663 Baffin Way within the Madison Club
development in the City of La Quinta, California.
Compaction testing was performed on July 30, 2013. Testing indicates that a minimum of 90
percent relative compaction was attained in the areas tested. The passing test results indicate
compliance with the compaction requirements of the California Building Code (CBC) and the
City of La Quinta at the tested locations and depths but are no guarantee or warranty of the
contractors work.
Field Tests: In-place moisture/density testing was performed using a nuclear density gauge in
accordance with ASTM Test Method D6938-08. A total of 7 density tests were performed. The
test results are summarized on the attached data sheet.
Laboratory Tests: The moisture -density relationships for the soil were determined in the
laboratory in accordance with ASTM -D Test Method 1557-91.
August 9, 2013 -2- Project No. 522-13109
13-08-388
If there are any questions regarding this report or the testing summarized herein, please contact
the undersigned.
Respectfully submitted
SLADDEN ENGINEERING
h� REIT L.
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AND
Brett L. Anderson c�
No. 045389
Principal Engineer
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ENGNEERING
Compaction/gvm
Copies. 4 / Discovery Builders California
Gladden Fnoineerina
TEST RESULTS
Project Name: Lippman Residence
Location: 81633 Baffin Way, La Quinta, Ca.
PROJECT NO: 522-13109
REPORT NO: 13-08-388
Test No.
Date Tested
Location
Elevation
Dry Density
in place
% Moisture
in place
Relative
Compaction
Maximum
Density
House Pad
1
07/30/13
Lot 1018
PG
106.9
8.4
93
115.0
2
07/30/13
Lot 101B
PG
108.5
7.5
94
115.0
3
07/30/13
Lot 1018
PG
107.9
9.0
94
115.0
4
07/30/13
Lot 102B
PG
105.8
10.1
92
115.0
5
07/30/13
Lot 102B
PG
107.1
8.5
93
115.0
6
07/30/13
Lot 1028
PG
107.5
8.2
93
115.0
7
07/30/13
Lot 102B
PG
109.1
9.3
95
115.0
PG = Pad Grade
August 9, 2013
Sodden Engineering
Sladden Engineering
45090 Golf Center Parkway, Suite F, Indio, CA 92201 (760) 863-0713 Fax (760) 863-0847
6782 Stanton Avenue, Suite A, Buena Park, CA 90621 (714) 523-0952 Fax (714) 523-1369
450 Egan Avenue, Beaumont, CA 92223 (951) 845-7743 Fax (951) 845-8863
800 E. Florida Avenue, Hemet, CA. 92543 (951) 766-8777 Fax (951) 766-8778
May 10, 2013 Project No. 544-13109
13-05-168
tt
Discovery Land Company
80955 Avenue 52 CITY O F LA Q U I NTA
La Quinta, California 92253
BUILDING & SAFETY DEPT.
Attn; Mr. Scott Birdwell APPROVED
FOR CONSTRUCTION
Subject: Geotechnical Update
DA By,,_4
Project: Custom Residence 1?�/�5'"
Lots 101B & 102B
The Madison Club
La Quinta, California
Ref: Geotechnical Investigation Report prepared by Sladden Engineering dated January
28, 2005; Project No. 544-4810, Report No. 05-01-101
Report of Testing and Observation During Rough Grading prepared by Sladden
Engineering dated March 2, 2006; Project No. 522-4810; Report No. 06-02-120
As requested, we have reviewed the above referenced geotechnical reports as they relate to the
design and construction of the custom residence proposed for Lots 101B & 102B within the
Madison Club development in the City of La Quinta, California. It is our understanding that the
proposed residential structure will be of relatively lightweight wood -frame construction and will
be supported by conventional shallow spread footings and concrete slabs on grade.
The lots were previously graded during the rough grading of the Madis
.rough grading included over -excavation and recompaction of the native
RIV)W
the placement of engineered fill material to construct the building pads. The site grading is
summarized in the referenced report of Testing and Observation During RQ1 Wft along
with the compaction test results.
Because the lots have been previously rough graded, the remedial grading i r QUr��
should be minimal provided that the building area that falls within the previously assume
building envelopes. The building areas should be cleared of surface vegetation, scarified and
moisture conditioned prior to precise grading. The exposed surface should be compacted to a
minimum of 90 percent relative compaction prior to fill placement. The previously removed soil
and any fill material should be placed in thin lifts at near optimum moisture content and
compacted to at least 90 percent relative compaction.
May 10, 2013 -2- Project No. 544-13109
13-05-168
The referenced reports include recommendations pertaining to the construction of residential
structure foundations. The previous reports also address the potential for liquefaction,
subsidence and differential settlement. Based upon our review of the referenced reports, it is our
opinion that the structural values included in these reports remain applicable for the design and
construction of the proposed residential structure foundations.
The allowable bearing pressures recommended in the referenced Geotechnical Investigation
report remain applicable. Conventional shallow spread footings should be bottomed into
properly compacted fill material a minimum of 12 inches below lowest adjacent grade.
Continuous footings should be at least 12 inches wide and isolated pad footings should be at least
2 feet wide. Continuous footings and isolated pad footings should be designed utilizing
allowable bearing pressures of 1500 psf and 2000 psf, respectively. Allowable increases of 300 psf
for each additional 1 foot of width and 300 psf for each additional 6 inches of depth may be
utilized, if desired. The maximum allowable bearing pressure should be 3000 psf. The
recommended allowable bearing pressures may be increased by one-third for wind and seismic
loading.
Lateral forces may be resisted by friction along the base of the foundations and passive resistance
along the sides of the footings. A friction coefficient of 0.48 times the normal dead load forces is
recommended for use in design. Passive resistance may be estimated using an equivalent fluid
weight of 300 pcf. If used in combination with the passive resistance, the frictional resistance
should be reduced by one third to 0.33 times the normal dead load forces.
The bearing soil is generally non -expansive and falls within the "very low" expansion category in
accordance with the 2010 (CBC) classification criteria. Pertinent 2010 CBC Seismic Design
parameters are summarized on the following page.
Based on our field observations and understanding of local geologic conditions, the soil profile
type judged applicable to this site is SD, generally described as stiff soil. The site is located within
UBC Seismic Zone 4. The additional coefficients and factors relevant to seismic mitigation for
new construction in accordance with the 2010 California Building Code (CBC) are provided in
this report.
Sladden Engineering
May 10, 2013 -3- Project No. 544-13109
13-05-168
The seismic design category for a structure may be determined in accordance with Section 1613
of the 2010 CBC or ASCE7. According to the 2010 CBC, Site Class D may be used to estimate
design seismic loading for the proposed structures. The period of the structures should be less
than I/2 second. This assumption should be verified by the project structural engineer. The 2010
CBC Seismic Design Parameters are summarized below.
Occupancy Category (Table 1604.5): II
Site Class (Table 1613.5.2): D
Ss (Figure 1613.5.1): 1.5008
S1 (Figure 1613.5.1): 0.600g
Fa (Table 1613.5.3(1)):1.0
Fv (Table 1613.5.3(2)):1.5
Sms (Equation 16-36 (Fa X Ss)): 1.5008
Sm1 (Equation 16-37 {Fv X Si)): 1.9008
SDS (Equation 16-38 (2/3 X Sms)): 1.000g
SDI (Equation 16-39 {2/3 X Sm1}): 0.600g
Seismic Design Category: D
We appreciate the opportunity to provide service to you on this project, if you have any
questions regarding this letter or the referenced reports please contact the undersigned.
Respectfully submitted,
SLADDEN ENGINEERING
SRETT L.
ANDERSON
Brett L. Anderson E'pA97,T07r4-
CIVIL
Principal Engineer ENGINEERING
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SER/gvm CAi
Copies: 4/ Discovery Land Company
Sladden Engineering
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LA QUINTA
Please verify that soils reports contain all of the above information. In addition, to assure
continuity between the investigation/reporting stage and the execution stage, please use
the following checklist to verify that the conclusions and recommendations in the report
cover all the required elements. Only then. can we be assured that the construction
documents address all of the site soil conditions.
La Quinta Geotechnical Report'Checklist
Does the "Conclusions and Recommendations" section of the report address each of the
following criteria?
"Address" means:
(a) the criterion is considered significant and mitigation measure(s) noted, or,
(b) the criterion is considered insignificant and explicitly so stated.
Yes No Criterion
❑ Foundation criteria based upon bearing capacity of natural or compacted soil.
❑ Foundation criteria to mitigate the effects of expansive soils.
❑ Foundation criteria based upon bearing capacity. of natural or -compacted soil.
❑ Foundation criteria to mitigate the effects of liquefaction.
❑ Foundation criteria. to mitigate the effects of seismically induced differential
settlement.
❑ Foundation criteria to mitigate the effects of long-term differential settlement.
❑ Foundation criteria to mitigate the effects of varying soil strength.
❑ Foundation criteria to mitigate expected total and differential settlement.
Any "No" answers to the above checklist should be noted as specific required
corrections.
BRETT L.
ANDERSON
No. 045389
Exp_ 9/30/14