Loading...
HomeMy WebLinkAboutTract Map 3929 Lot 257 Grading Compaction Tests "' e RECEIVED OCT 2 1 2002 CITY OF TEMECULA ENGINEERING DEPARTMENT Mrs. Kim Grobler 30290 Church Hill Ct. Temecula, CA 92591 Subject: . !l ?AZ~ L.o, Z::S 1 WAC GEDTECHNICAL -mc. October 16, 2002 W.O. 00576 Report of Grading Compaction Tests for Intended Residential Building Construction, Property Known as Lot 257, Tract 3929, City of Temecula, County of Riverside, California A.P.N.921-232-003 Dear Ms. Grobler: This report presents the results of our grading observation and compaction testing conducted during the placement and compaction of the fill for the property known as Lot 257, Tract 3929, City of Temecula, County of Riverside, California. The property is programmed to host residential construction. The results of fill compaction tests performed are presented herein. The results of the laboratory determined Maximum Dry Density-Optimum Moisture Content of the soil type used during grading are shown within tabulations of soil compaction tests. Approximate locations of fill compaction testing are shown on Plate 1. Grading Observations and Compaction Testing: The opinions presented herein are based upon our compaction testing and observations of the grading procedures used, and represent our opinion as to the contractor's compliance with the project plans and specifications, and did not include any supervision or direction of the actual work performed by the contractor, or his workmen at the site. In general, following site clearance, surficial soils were cut to expose competent natural subgrades on which to place new structural fill to support fill slope/pad construction. Removal depths reached, on average, 3.0 feet below original grade for exposure of competent subgrade materials (minimum 90% relative dry density as compared to the prevailing maximum dry density). Upon exposing .competent natural bearing soils, a minimum of 15 feet in width keyway with heel founded I foot deeper than toe was constructed; exposed surface was scarified to a depth of 6-inches and compacted to a minimum of90% of the laboratory Maximum Dry Density. Local soils were used .as fill blanket material compacted to a minimum of 90% relative compaction for '.a. IDZ 3&. . nUl NDrtb Sbm ar. . 'IWDSkID, CISII33 (8m 888-m? . (SaSl m-III? . '11 (SDBl m.m? \ Page 2 . A.P.N.9.-003 the fill placed. During grading, line and grade for planned pad and slope areas were supplied by the project civil engineers. WAC Geotechnical, Inc. assumes no responsibility pertaining to the correctness of the building pad locations and/or of the finished grade elevations supplied. In general, mass grading and compaction testing of the fill placed within the limits of grading were performed as described below: I. Vegetation, surface trash and other miscellaneous debris were cleared off the areas to be graded and such were disposed of, outside the grading area, prior to actual grading. 2. The exposed surface area to receive fills was overexcavated 3 feet. Slopes were founded upon 15 foot wide keyways with heel founded I foot deeper than toe. Prior to fill placement, exposed surface was scarified, moisture conditioned and compacted to at least 90 percent of the applicable laboratory Maximum Dry Density as determined per ASTM D1557-91 test method. Slope face was track rolled every 4 vertical feet. 3. Approved on site stockpiled soils were placed in thin lifts by using a 6H dozer, moisture conditioned by water truck and compacted. Each layer was compacted to at least the specified density before the next layer was added. 4. Placement of compacted fill continued to the approximate limits and grades as determined by the project surveyor and/or by the grading contractor. 5. Building pad was constructed as a cut pad. Conclusions and Recommendations Based upon the observation of the construction sequences used during grading, it is our opinion that the compacted fill for slope and pad construction has been placed in accordance with the requirements set forth in current UBC, the project plans specifications and the local governing agency. The compacted fill placed for pad area is intended to support graded pad area. Cut building pad is intended to support concrete slab-on-grade and foundations for residential structure and is approved for such use by this firm. Foundation recommendations and soil values presented are applicable to subject project. It is suggested that future earthwork, if any, requiring additional fill placement beyond the limits and above the current finished grades for building pad, should be performed under direct review , of the project soils engineering consultant. Should additional structures for the subject site, ; beyond the area of the structural pad for residential structure be planned, it is recommended that : additional subsurface soils engineering investigation be conducted followed by a report and : recommendations specific to planned buildings. WAC Geotechnical, Inc. 2- Page 3 . A.P.N.94.003 It is recommended that all load bearing footings should be located only within the areas of the prepared graded cut pad building footprint. Footing excavations should be approved by WAC Geotechnical, Inc. to ensure that suitable soils have been penetrated and that excavations are free of loose or disturbed soils. At time of covering, subgrades for paving and floor slabs should be moisture conditioned and should be firm, unyielding and protected by vapor barrier where required. To prevent futUre cracking of concrete slabs-on-grade, ids recommended that no dumping of loose and/or excess soils derived from footing and utility trench excavations be allowed on the individual subgrades prepared to receive concrete slabs-on-grade. WAC Geotechnical, Inc. will assume no responsibility, whatsoever, inthe event concrete is poured without proper field review of slab-subgrades and foundation excavations by this firm. Foundation trenches should be constructed only in prepared cut pad area and should be free of loose soil prior to concrete pour. Foundation excavations should be approved by this office and be corrected, if necessary, prior to further construction. Prior to pouring concrete, foundation excavations should be pre-moistened. To prevent foundation distress due to water migration, use of planters adjacent to footings should be avoided. WAC Geotechnical, Inc. assumes no responsibility in event foundations are , distressed during lifetime use of the property due to foundation soil saturation from planters. If planting of landscaping around structural footing areas cannot be avoided, a concrete planter box : should be constructed with drainage collection points which allows for removal of water away from footings. A landscape architect should be contacted for design. Design of planter boxes : adjacent to footings should be forwarded to this office for review and comment. Care should be I taken to assure that drainage is directed away from structural foundation areas. The soil materials underlying proposed foundation areas are considered to have very low I expansion potential. I Spread Foundations i For adequate support, the proposed structures may be constructed on continuous and/or isolated , spread footings founded exclusively into field approved, compacted fill materials. Conventional shallow foundation system is considered suitable for planned residential and . ancillary structures. Sulfate content is considered to negligible (less than 100 ppm) for site.soils. Type II cement is considered to be acceptable for the subject project. . Foundations may be designed based upon the following values: Allowable Bearing: Lateral Bearing: .sliding Coefficient: 1500 Ibs./sq.ft. 255 Ibs./sq.ft. per foot of depth to a maximum of 1500 Ibs./sq.ft. 0.28 WAC Geotechnical, Inc. :? Page 4 . A.P.N.94.003 The above values may be increased as allowed by Code to resist transient loads such as wind or seismic. Building code and structural design considerations may govern depth and reinforcement requirements and should be evaluated. 2. Other Design Recommendations * FOOTING DEPTH Exterior 12-inches below lowest adjacent grade in approved bedrock materials for one story and IS-inches below adjacent grade in approved bedrock materials for 2-story . Interior 12-inches below lowest adjacent grade in approved bedrock materials for one story and IS-inches below adjacent grade in approved bedrock materials for 2-story . * FOOTING WIDTH Exterior 12-15 inches minimum for one and 2-story, respectively. Interior 12-15 inches minimum for one and 2-story, respectively. * FOOTING REINFORCEMENT Exterior & Interior All continuous; four No.4 bars, two near the top, two near the bottom for exterior and two No.4 bars, one near the top and one near the bottom for the interior. Concrete Slabs Slab Thickness: 4-inches net, reinforced with 6x6-6/6 WWF, or with #3 rebar at 16-inch o/c, is recommended. Reinforcement should be installed at mid-height in the slab. * Under-Slab Treatment Living Areas 10-mil Visqueen; cover with at least 2 inches of sand. Subgrade soils should be presoaked to contain at least optimum moisture content immediately prior to placing Visqueen and to be verified by the soils engineering consultant. The sand cover should be moistened prior to placing concrete. Grade Beam A grade beam reinforced continuously with the garage footings should be constructed across all garage entrances, tying together the ends of the garage footings. This grade beam should be embedded at the same depth as the adjacent perimeter footings WAC Geotechnical, Inc. .\ Page 5 Garage Slab . * Fireplace Footings - A.P.N.94.003 Optimum moisture content in subgrade soil verified by the soils engineering consultant. Fireplace footings shall have a minimum embeddment depth of 12-inches measured from the lowest adjacent grade and should be an integral part of the building foundation system. Fireplace slabs shall be treated in the same manner as the living area slabs. .Prior to pouring footings, soils should be pre-moistened and field approved by the project soils engineering consultant or his representative. The settlement of properly designed and constructed foundations supported on approved earth materials, carrying maximum anticipated vertical loadings, are expected to be within tolerable limits. Estimated total and differential settlements are about 3/4 and 1I2-inch for 40 lineal feet, respectively. WAC Geotechnical, Inc. 5' . . Closure Compacted fill placed is in accordance with the prevailing state-of the-art in the field of soil mechanics and foundation engineering and as recommended in by this firm. Fill materials placed are intended to support prepared slope and pad areas and driveway construction. Prepared cut pad is to support concrete slabs-on-grade and load bearing foundations. Soils used during grading are considered to be silty fine to very coarse-grained sand. The soil material for building support is considered to have very low expansion potential. To minimize potential differential settlement to footings, it is suggested that following excavations, excavated trenches shall be verified to ensure presence of only native soil materials underneath foundation bottoms. As recommended herein, use of planters adjacent to footings shall be restricted to minimize potential foundation settlement due to water migration. Should planters be placed in proximity to footings, planters should be within a sealed box area equipped with drainage system to direct excess water away from footing area. To prevent moisture migration to moisture sensitive areas, it is recommended that a vapor barrier, in the form of Vis queen or other commercially available similar products, should be used with proper protective coverings (sand, no gravel or rock) prior to concrete pour. The recommendations and opinions provided herein are based upon our observation of grading conducted during fill placement. We offer no other warranty other than striving to perform in a manner as generally used during site preparation and grading .for similar grading projects within the County of Riverside. . Thank you for the opportunity to be of service on this project. Should you have any questions regarding this report, please call the undersigned at your convenience. '" . . c Table 1 Compaction Testing Field Density Test Results (ASTM: D 2922-96) Test No. Test Depth In Place Moisture Max. Relative (elevation below Density Content Dry Compaction finish grade, feet) (PCt) (%) Density (%) (pct) Test Date 10/2/02 I, Slope 122.8 8.7 127.3 96.5 2, Slope 123.9 8.9 127.3 97.3 3, Slope 121.5 9.2 127.3 95.4 4, Slope 121.0 9.0 127.3 95.0 5, Slope 118.1 8.8 127.3 92.8 6, Slope 120.3 8.6 127.3 94.5 7, slope 119.7 9.1 127.3 94.0 8, Slope 119.6 9.0 127.3 94.0 9, Slope 118.2 8.8 127.3 92.9 10, Slope 117.4 9.1 127.3 92.2 Test Date 10/11/02 II, Pad 121.2 9.0 127.3 95.2 12, Pad 120.5 8.8 127.3 94.7 13, Pad 120.3 9.2 127.3 94.5 14,Pad 122.4 8.9 127.3 96.2 15, Pad 118.6 9.1 127.3 93.2 16, Pad 119.4 8.7 127.3 93.8 Maximum Dry Density/Optimum Moisture Content Relationship (ASTM Dl557-91) 127.3 @ 9.0% WAC Geotechnical, Inc. 1 .--t==:<_.........~ . . . - . . aTE .....,'-_...". .. -. -. .J' ...~............ .... " _,;. _.',. '9_;._, .....; ._ :"',"_' . t. AVENIDA",--'BARCA .'-. ,= [. 1~ "s;' .n,tj> -. .. ifT'J :~;:g"~3-" ;::0 -' -~ ~~1-- -=.L..~~-=--=--=-~=_-=- ~. R:'1B" ,__ '__. "'. -=:. --=----......:.. I'Ve --... \' J\A:. . N 27-42'34" W \: 79.80' D."".Ol' 22" ~'~!2 '~ _ ~4~' ._ ~- / ~ .' '_',",. ".,., .--1" L ".2(" -.. IV,. . -IJ.;/'J ~ _ _ __ _ -- S 35'12" &"',r. ~ /I tI ..it - _. ,l '.' 1"1 23.68" W :;'~"':+.I ; ,,~. 3' f/l(l) . "". "C<\st, . Wlo~*~ :\ \I; . - '..ITIKS .,:}Y II ~ I' (9: I " ~f II!? '7<.) ij ~T~ ~, "D"~j ~ ~ ,.., > w a: ~ w I- Z 0 ~ <1 > R" ES ~ .. U[ ~ Z-1 Ill' To ... - ;.. . ... .. Z j!t1'!.<I ~ --e -; .If-,-- <$ oN; '" . .. . .. '" l? z ,..' UGT pa:. / "'1~1 o.T.~.7.D1. r"llo.l )RESS' i READ THIS'NOTICE I I UANCE OF TMIS PERMIT BY THE CITY OF TEMECULA I lOT IMPLY _ OR. PROVIDE A1JY CLEARANCES FROM !JR FEDERAL W1LCUFE AGENCIES REGULATING'THE , ONS OF THE CALIFORNIA OR NATIONAL ENDANGERED iACTS. ,. , I o , G,O i 11.,' "'~ !,~'1 OfS."-I"""'TtlI!: \ i>l ~ """\ "- \ " ' ... "- ~ ~ . r~ ~) ~ VIA Ft'otl1El2BY i!. t-'l(':-~":; ,~'~_ , '~. , . _ -L . .,y:-- (h~C) E:ERI I:~.. " <;CAl.E.' I". Wi Eros i on Contra I & GR.A.DING PLA.N iD 2P AD l!<J , . 1 Lc.<jcnol X -4 :::. ,Q fprol< i Y~\C~+e / ocatl 01"\ o~ . ~Oj'Ylpac.tion fe.sf ~ PLAT f '~