The URL can be used to link to this page

Home My WebLink AboutTract Map 3883 Lot 324 Limited Geotechnical Study Fr;,lay. ,Ma".h 02, 2001 6;04 .~~,1 . . Ken Schaomann 909-694-1401 . r:.C2 -m .3843 I.e'r 3 ! , C . .S~dt'.'.k1~",(,CGMtJ~SIr\_.EIIl~h;t0. G'~TtI:i"9 . N~~g.... C~$UUCl'onMller~f_~ .~~. "'II'~ O!"QOratlon .,_....IUuq"... . "'''''.IIt'''...""."",,-_ ENVIRONMENTAL & GEOTECHN'CAL ENGINEiRING NEiWORK January 4,2001 RECEIVED MAR 1 2 2001 CITY OF TEMECULA ENGINEERING DEPARTMENT Mr. Ken Schaumaon 40420 ClIllo Toreide Tem,cula, California 92591 (909)699-5113 I FAX (909) 694-1401 Regarding: LIMITED GEOTECHNICAL STUDY Proposed Single Family Residence South Comer.of Called Madeno and La Colima Road City of Temecula, County of Riverside, California F'roject Number: T2252-LGS Reference: 1. Acaclemv Consulting Corporatlon, Rough Grading Plen for Ken Shaumann. plans undated. , Cear Mr. Schaumann: ~ Per your request and signed authoriZation. a representative of this firm hes visited the slJbject site on : December 29. 2000 to vial.lally observe the Sl.Irface within the subject lot. Baaed on this finn's I eXpllrience with this type of project and on the well known and relatively cimplictio underlying ; geologic conClilfona of the site end Immediate vicinity, subsurface exploration was not considered 'necessary. However, in lieu of subsurface exploration, additional 9r'llding beyond that anticipatild In .this report may be'necessary depending on exposed conditiollll encountered durIng grading. 11.0 SITE I PROJECT DESCRIPTION 1.1 Loc.tion I :Proiect CBBcrIDUon: The subject property is localed at the south oorner .of Calle Msdero and La Colima Road in the Cily of Temecula. The proposed development is a one or two atOlY. :slab-on-grede residential structl.lre. The remainder of th~ site wW consist of hardscape and landscape improvements, Relativeiy minor cuts and fills are proposed. 1.2" - - \ F,i;loy,Mo",h 02, 2001 6;04 AM '. Ken Sohoomonn 909.894-1401 . ~.05 I I I I I I I I I I - I I I - I I I .. '. '. II . 3.0 3.1 4.0 4.1 2.2 Mr. Kin Schaum.nn Projoct No; T22S2-LGS January 2001 Page 3 · An expansion tes1 should be performed on a representative solllample retrieved from tI1e flnished pad area subgrade so that foundation recommendations can be verified. Structural FIIl.i All fill meterial, whether on-eite material or Import, should be approved by the Project Geotechnlc;ll Engineer and/or his representatfve before placement All fill should be free from vegetation, organio material, and other debris. Import fill should be no more exp:mcivl;I than the exioting on-site material. Approved fill materIal should be placed in horizontal lifts not exceeding a.o to e.o-Inches In thickness and watered or aerated to obtain nOllr-optimum moIsture COntent (2.0 perc:ent of optimum). Each lift should be lipread evenly and should be thonoughly mflCed to enlure uniformity of soil motsMe. Structural fill should meet a mInimum relative compaction of 90 percent of maximum dry density based upon ASTM 01557-78 (90) procedures. Moisture contant of fill materials should not vary more than 2.0 pefCllnt of optimum, unless eppnoved by the Project Geotechnical EngIneer. FOUNDATION DESIGN RECOMM~NDATIONS aeneral: Foundations for the propoSed structure may consist of conventional' column footings and contlnuol.ls wall footings founded in competent engineered fill. Minimum footing depth should be lS-lnches below lowest adjacent grade. Recommendations for foundation design and construction should be pnovldad tly the Structural Engineer In accordance with the latest edition of the UBC and should ba based on geotElchnlcal characteristics for competent fill consisting of silly sand (SM) and a very low expansion pctantial (EI:rO) for the supporting salls and shOUlc:l not preclude more restrictive structural requirements. The following seismic parameters apply: Typo or Fault: Typa B Fault Closaat Dlstanoe to Known Fault: Less than 2Km Soli Profile Type: So . RETAINING WALL RECOMMENDATIONS Earth Pressures: RetaInIng walls backfillec/. with non-expansivEl granUlar soil (EI-O) or very low expansive potential mallriala (Expansion Index of 20 or less) within a zone elClending I.Ipward and away. from the he.1 of the footing at a ,lope of 0.5:1 (horizontal to vertical) or flatter can be deSigned to rellst the following static lateral sOil preasures: EDGEN Corp""",lo. 2.. . . p.04 Mr. Ken SChaum.n" Prcject No: T2252-LOS January 200' Page 4 Condition leVa Backfill Active 30 cf At Rest eo F\ll1her exps",slon testing of pOlel}Ual backfill material should be. performed at the lime or ,reialning will construction to detarmine suitability. Walls that are free to deflect 0,001 I'lldia.~ '.' .,' .... , . at the top lIhould be designed for the above-recommended actiVe condition. Walls that are not capable of this movement should be sSlIumed rigid and designed'for th. Gt-reet condition, The abovlij values assume well drained backfill and no buildup of hydrostatio pressure. Surcharge loads_ dead snd/or IiV!l. acting on the bar;kfill within a horizontal distance behind the wall should also be oonsidered in the design. Uniform surcharge pressures Should be ~pplied 80 en additional unifolT11 (rectllngular) pressure distrlbution, The lateral earth preasure coefficient for a uniform vartical surcharge load behind the wallis 0.50, 14.2 FOl&ndatlon Ollslan: Retaining wall footings should be founded to the same depths into properly compacted fill, or firm, complltent, undisturbed, natural SOllllS standard foundations and may be designed for the same allowable bearing value as determined psr Section 3.1 (as long as the resultant force Is located in the middle one-third of the fOOling). and with the 8llm. allowable static Ia:teral, bearlng pressure and allowable sliding resistance as determined per Section 3.1. HOWever, retaining wall footings determined to be fully embedded in unweathered bedrock may be designed for an allowable besrtng value of 3,000 pounds per squire foot and lateral bearing of ,3~O pounds per equare foollfoot of d~plh. Whlin using the allowable lateral preseure and Illlowable aI/ding resistance, a factor of safely of 1.5 should be ., achieved. , 4.3 Subdraln: A lubdrain system should be constructed !:>ehind and at the base of all retaining wslls.to allow drainage and 10 prevent the buildup of excessive hydrostatic pressures. Typical subdrains may include weep holes with a continuous gravel gallery, perforated pipe sUr/,?und8d by filter. rock, or some other approvecl system. Gravel galleries and/or filter nock, if not properly designed and graded for the on-sije and/or Import matertals. should b. enclcsad in is geotextile fabric such as Miraii 140N. Supac 4NP, or a suitable substitute In order to prevent Infiltration ,of fines and Clogging of the system. The perforated pipe. choulci be at least 4.0 inches In diameter. Pipe perforations ahol.lld be placed downward. Grevel filters should have voluma of at least 1.0 cubic foot per lineal foot of ~ip.. Subdraln. ehould ...- - -.-. _. - --. -_. -. _. - ..-.,-. .. EnGEN CorpOtati... . c3 ~ _riday, Ma..h OZ, 2001 8;04 AM . Ken Scha'J:nann 909-694-1401 . 1>.03 Mr. Ken Schaumann Project No: T22S2-LGS January 2001 Pave 2 associated with liquefaction is considered low. No known active feults traverse the site. Base6 On favorable topography, the potential for hazards associated with nockfalls or landslides is considered low. No unusual geologioal concilllons were noted. 2.0 EARTHWORK RECOMMENCATIONS 2.1 All Aress; · All veglltation should be removed from areas to be graded and not used in flUs. · The proposed structure lIrea and areas to rec9ive fl1l will reQl.lire the removal of slopewash and weathered bedrock. Depths of removals are elCpecied to be up to two (2) to three (3) feet below existing grades. Deeper removals mOlY be required depending on exposed conditions encountered. . Based on th.. Referenced No. 1 plllflS, a cul/flll transition traverses the proposed structure aree. Therefore, after removals, the cut portion (and shaliow fiU portion) will need to be overexcavsted so that a minimum of 18-inchss of engineered fill exists below the bottom of all footings. Horizontal eXlent of overelCcavation should be e minimum of five (5) feet outside of the perfmeter footings or equal to the depth of the deepeat fill below pad grade, whichever is greater_ . All removal and overexcavation bolloms should be Inspected and tested by the Soil Engineer's representative prior to pladng flll. Rarnoval Elnd overexclIvlltion bottoms whiCh test at 85% reletive compaction, or better, will be considered acceptable, After bottom approval. all bottoms IIMould be soarifled 12-inohes, moisture conditioned to near optimum moisture and then racompacled to a minimum of 90 percent re!etive compaction. . Ail pnoposed hardscape areas shol.lld be removed two (2) feet below Proposed grades or exIsting grades, whichever is deeper. RemOVals will not be required If proposed grades expose competent bedrock or competent native soils. The expOSed bottoms should be scarified a minimum of 12-inches, moisture conditioned to near optimum moisture and then rscompacted to at ieast 90 perCQnt relative oompaction prior to placing fill, , , EnGEN Co<porotioo --'-"-' -"- .." -- .- -. - --. .-. -.- .. .._- -\