HomeMy WebLinkAboutCT 72-24; Spanish Village Unit 1; Soils Report Update; 1978-01-27P c 7z2?2 WILLIAM 5. KAOOS~KOS 6. ASSOCIATES
w 5, KR00s*05. ClVlL EIIOlNEER FOUNOATION ENGlNEERlNG
AL “ENTON. ENGlNEERlNG GEOLOGIST ENGlNEERlNG GEOLOGY
4320 “ANDEVER AVENUE . SAN rIlEGO. CAL.IFOR>IIA ‘JLIZO . PHONE 2”3650tj
CT72 -3 <f January 27, 1978
Mr . Ed Elliott
McMillin Construction Company 30th Street & "B" Avenue National City, California 92050
Job No. 78-5569
RECEIVED
SUBJECT: Report of Soil Investigation Lots 3, 4-6, 8, 10-13, 16, 20-23, 25-29, 32-36, 46, 50, 54, 59, 61-64, 68-70, JAN 2 0 ig7a
78, 79, 81, 88-91, 105 & 106 Spanish Village IJnit No. 1
Pnillo FJay & Palenquc Street CITY OF CARLSBAD
Carlsbad, California BuilW Department
Dear Mr. Elliott:
In accordance with your request, we have conducted an investigation of the surface and subsurface soils at the subject lots of Spanish Village Unit No. 1.
The enclosed report summarises the results of our investigations
and the recommendations made by our firm for the proper design of
the structures and other improvements to be located on the subject
lots.
Spanish Village Subdivision Unit No. 1 (Carlsbad Tract 72-24) is
located northerly of the intersection of Anillo bray and I'alenauc
street, Carlsbad, California.
The subdivision has been previously graded and improved with streets and curbs.
The grading work was performed in conformance with the recommendations
summarized in the Report of Preliminary Soils, Investigation of
Spanish Village Unit Nos. 1 and 2, by Renton Engineering, Inc., dated
May 10, 1973. The grading work and the relative compaction of the fill soils were certified in the Final Report on Compacted Fill Ground
of Spanish Village Unit No. 1 (Carlsbad Tract 72-24) by Aenton
Engineerinq, Inc., dated January 8, 1975, their Project No.73-11-12-D.
FIELD INSPECTIONS AND INVESTIGATIONS: ____-
Our engineering qeologist and soils enaineer, performed a visual inspection of the subject lots of Spanish Villaqe Unit Xo. 1. in
order to further classify the existinq hearinq soils a thorough
review of the aforementioned reports by Benton Engineering, Inc. was conducted.
Page 2
Report of Soil Investigation
Lots 1, 4-6, 8, 10-13, 16, 20-23, 25-29,
32-36, 46, 50, 54, 59, 61-64, 68-70,
78, 79, 81, 88-91, 105 & 106 Spanish Village Unit No. 1 Anillo Way & Palenque Street
Carlsbad, California
Job Ho. 78-5569
CONCLUSIONS AND RECOMMENDATIONS: -I_
The following summarized conclusions and recommendations are based on the analysis of all the data and information obtained from the
soil investigation. This includes our visual inspections of the
building sites; a review of the reports by Denton Engineering, Inc.; and our general knowledge and experience with the natural ground soils and compacted fill soils that exist on this subdivision site.
1. The natural ground soils and compacted fill soils on the subject lots have been classified as silty fine sands to medium sands.
These soils are non-expansive: therefore, possess less than 3.0 percent swell as measured by the County of San Diego Test for
Fxpansive Soils.
2. The natural ground soils were properly prepared to receive the
fill soils. The fill soils were properly placed and compacted to
at least 90 percent of maximum dry density.
3. The proposed single and two story dwellings may be desiqned with continuous foundations and spread footings that extend 12 inches into the compacted fill ground and the compacted natural ground. ?lo special reinforcement or treatment of the continuous founda-
tions, spread footings and concrete floor slabs is recuired.
4. The proposed continuous foundations and spread footings when founded 12 inches into the compacted fill ground and compacted natural ground may be designed with a soil bearing value of 2,000 pounds per square foot. This soil bearing value may be increased one-third for design loads that include wind or seismic analysis.
5. Existing natural ground cut slopes and compacted fill slopes of maximum inclinations of 1.5 horizontal to 1.0 vertical will be
stable for the materials native to these sites.
6. Planter areas adjacent to the structures shall be constructed to slope away from the foundations and floor slabs (minimum of one percent). Planter boxes adjacent to the structures shall be constructed with drain tile in gravel directing the subsurface
waters away from the structures towards the lower level of the sites.
7. Future swimming pools or other subsurface structures shall be properly designed and reinforced with steel to reflect any potentially expansive clay soils that could underlie these residential sites. The design of these subsurface structures shall follow the recommendations of a structural engineer and soils engineer.
Page 3
Report of Soil Investigation
Lots 1, 4-6, 8, 10-13, 16, 20-23, 25-29,
32-36, 46, 50, 54, 59, 61-64, 68-70, 78, 79, 81, 88-91, 105 & 186
Spanish Village Unit MO. 1
Anillo Way & Palenque Street Carlsbad, California
Job No. 78-5569
8.
9.
10.
11.
12.
Backfill soils behind retaining walls and in utility trenches which support structures, patios, sidewalks, driveways, asphalt pavement, etc., (other than landscaping) shall be placed and compacted to at least 90 percent of maximum dry density.
The compacted fill soils that occur within five feet of the
fill slopes possess poor lateral stability, even thouqh they have been certified to a relative compaction of 90 percent of maximum dry density or better. Proposed structures and other
improvements such as walls, fences, patios, sidewalks, swimming pools, driveways, asphalt pavement, etc., that are located
within five feet of the face of compacted fill slope could suffer differential movement as a result of the poor lateral stability of these soils.
Foundations and footings of the proposed structures, walls, etc.,
when founded five feet and further away from the top of compacted fill slopes may be of standard design meetinq the requirements of
the governing agency and designed in conformance with the
recommended soil bearing value. If proposed foundations and footings are located closer than five feet inside the top of compacted fill slope, they shall be deepened one foot below a 1.5 horizontal to 1.0 vertical line projected outward and downward from a point five feet horizontally inside the top of compacted fill slope (Refer to Figure No. II)
All compacted fill slopes and natural qround cut slopes (that do
not consist of dense soils or rocks) shall be planted with an
erosion resistant plant following the general requirements of the City of Carlsbad.
Adequate measures shall be undertaken to properly finish qrade the sites after the structures and the other improvements are in place, such that the drainage waters from the improved sites and the adjacent properties are directed away from the foundations, footings, floor slabs and tops of slopes, via surface swales and subsurface drains towards the lower level of the sites or to the
natural drainage direction for this area. Proper surface and
subsurface drainage will insure that no waters will seek the
level of the bearing soils under the foundations, footings and
floor slabs which could result in undermining and differential
settlement of the structures and the other improvements.
LIMITATIONS:
The recommendations summarised in this report are based on the evidence attained from our visual inspections of the residential sites and review of the aforementioned soils reports by Benton Engineering, Inc., and our general experience with the soils native to this subdivision site.
Page 4
Report of Soil Investigation
Lots 1, 4-6, 8, 10-13, 16, 20-23, 25-29
32-36, 46, 50, 54, 59, 61-64, 68-70, 78, 79, 81, 88-91, 105 & 106 Spanish Village Unit No. 1
Anillo Way & Palenque Street
Carlsbad, California
Job No. 78-5569
It is the responsibility of the owner or developer to insure that the recommendations summarized in this report are carried out in the
field.
This report and all subsegucnt reports and addendums automatically
become a part of the building specifications.
If you have any questions concerning this report, please do not hesitate to call us.
Respectfully submitted,
P!ILLII?M s. KROOSKOS L ASSOCIATFS
WSK:ck
(5) Addressee
RCE 11318
Concrete Floor Slab
- mpacted Fill Slope Maximum Inclination 1.5 : 1.0 -. _
-. L .- --- \ CO:
.- . _-_. - "_.
Reinforcement of . . - _,_.-', -.
Foundations and Floor Slabs:' - .+ y. U.\' following the recommendations -. 2 .*'. ': .- of the Architect or Structural- Engineer --c . -
Top of Compacted Fill Slope
Concrete
. . Compacted Fill /-. __-
TYPICAL SECTION
( Showing Proposed Foundation Located Within Five Feet of Top of Compacted Fill Slope)
Job NO. 78-5569 Figure No. II
,
Attachment 1 PJ4.E 1
GRADI:JG SPECIFICATIONS -- --
CEKERAL: The intent of this item is to properly establish procedures
for: clearing, CompaCting natural ground, preparing areas to bc filled, and placing and compacting fill material to tllc grades and slopes as
shown on the approved plans.
CL!:ARING: All vcgctation, ------- brush and debris shall be removed, piled and burned or otherwise disposed of to give the surface a neat and finished appearance.
COMPACTING NATURAL GROUND: After clearing, the natural ground s!lall
be --___ scarifiato a depth of at least 12 inches, watered to ontimum
requirements and compacted to not less than 90 percent of maximum dry
density, according to A.S.T.M. Test Method D 1557 in a four inch dia-
meter cylindrical meld of 1/30th cubic foot volume. Field den&it:>
tests shall be taken in the natural ground in accordance with ,Y.S.'l'.ll. Test Method D 1556.
FILL MATERIALS: Materials for the fill shall be approved by the soils engineer and shall be free from vegetable matter and other deleterious
substances. In the event that expansive materials arc cncountered within two feet of finish grade they should be either entirely removed or thoroughly mixed with good granular material before incorporatincj
them in fills. No footiny shall be allowed to bear on soils which in the opinion of the soils engineer arc detrimentally expansive, unless designed for this clayey condition.
PLACING AND COMPACTING FILL MATERIAL: After preparing the areas to
be f' illed, the fill mat%~ls shall be placed in layers not to exceed
six inches in compacted thickness. Each layer shall be watered to
optimum requirements and compacted to not less than 90 percent of maximum dry density in accordance with A.S.T.!l. Test Method D 1557. Compaction of the fill shall then proceed in the spccificd manner
to the grades as shown on the approved plans.
When the slope ratio of the original qround is steeper than five hor-
izontal);,to one vertical,
benched:
the oriyinal ground shall be steeped or
Ground slopes flatter than five horizontal to one vertical
shall~be benched when considered necessary by the Soils Engineer. Fill slopes shall be compacted by means of shecpsfoot roller or other suitable equipment. slopes are stabie, Slope compaction shall be continued until the
but not too dense for planting.
Field density tests shall bc taken when considered necessary by the
soils engineer in accordance with A.S.T.Y. Test Method D 1556 and shall be made not cxcecding two feet in vertical height, providing each layer is tested.
SUPERVISION: Continuous supervision of the fill shall be made by the representative of William S. lirooskos & Associates during the
grading operation so that he can certify that the fill was placed in accordance with these specifications.
SEASON LIMITS: --~ No fill material shall be placed, spread or rolled during unfavor .ablc weather conditions. When the work is interrupted
by heavy rain, the filling operation shall not be resumed until.field tests indicate that the moisture content and density of the fill arc
as previously specified.
'JlJIFIED SOIL CLASSIFICATION CHART
SOIL DESCI~IPTIOi'I GROUP SYMBOL TYPICAL NAMES -
COARSE GRAINED More than
half of material is larger
than a No. 200 sieve. GRAVELS CLEAN GRAVELS More than half of Coarse fraction is larger than
NO. 4 sieve size but smaller than 3".
GRAVELS WITII FINES
(Appreciable amount)
SANDS CLEAN SANDS
More than half of coarse fraction is smaller than a No. 4 sieve
SANDS WIT11 FI!JCS
(Appreciable amount)
GW
GP
G?1
GC
SK
SP
SM
SC
FINE GRAIKED More than
half of material is
smaller than a No. 200 sieve.
SILTS AND CLA';S ML
Liquid Limit
less than 50 -- -
SILTS AND CLAYS
Limit Liquid greater than 50
HIGBLY ORGANIC SOILS
CL
OL
Ml1
Well graded gravels, gravel
and sand mixtures, little
or no fines. Poorly graded gravels,
gravel and sand mixtures, little or no fines. Silty gravels, poorly graded gravel-sand-silt mixtures. Clayey gravels, poorly graded gravel-sand-clay
mixtures.
Well graded sand, gravelly
sands, little or no fines. Poorly graded sands, gravcll) sands, little or no fines.
Silty sands, poorly graded sand and silty mixtures.
Clayey sands, poorly graded
sand and clay mixtures.
Inorganic silts and very
fine sands, rock flour,
sandy silt or clayey-silt sand mixtures with slight plasticity. Inorganic clays of lot to Medium plasticity, gravelly
clays, sandy clays, silty
clays, lean clays. Organic silts and organic silty clays of low
plasticity.
Inoryanic silts, nicaceous
or diatomaceous fine sandy or silty soils, elastic
silts.
Cl!
OH
PT
Inorganic clays of high plasticity, fat clays. Organic clays of medium to high plasticity.
Peat and other highly
organic soils.
WLLIAM S. KROOSKOS & ASSOCIATES Soil and Foundations Engineers