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HomeMy WebLinkAboutCT 73-01; CONDOMINIUM COMPLEX SOUTH OF ADAMS STREET; SOIL INVESTIGATION; 1972-12-08• • • • • • • • • • " " . WILLIAM S,. ·IlROnSliBS'· & AS50-GIATES' W. S. KROOSKOS, CIVIL ENGINEER .AL..VENTON, ENGINEERING GEOLOGIST 432:0 VANDEVER AV'ENUE • SAN DIE;GO, CALIFORNIA 9212.0 DecemberS, 1972 Mr. William L. Zongker, President Coninmark P.O. Box ;39172. San Diego, c.alifQrnia 92109 SUBJECT: Report .of~-:e-s-t-:-i-9~~ Condominium Complex South of Adams Street, Nort~6f Agua Hedionda Lagoon Carlsbad~ California Dear Mr. Zongker: • 'FOUNOAT-ION ENGINEERING' . ENGINEERlt;C; GEOLOGY Job No. 72-3528 eT7s-o' In accordance with your request we have conducted an investigation of the surface and subsurface soils at the site' OT the proposed condomihium complex located south of the intersection. of Adams . Street and Highland' Drive 'in the City of Carlsbad, California. The enclosed report summarizes the resul;ts of the subsurface. explorations, test results of the typical bearing soils/ and' the recommendations made by our' firm for the proper design o'f the structures and the development of the site to receive.the.proposed improvements. . Our inve'stigatiO'n reveals that the ,site cOhtains exparts.ive sandy clay topsoils •. These natural ground soils·extend approximately two to three feet below the top of existing ground. It is our opi.nion, that if these expansive natural ground s·oils and the other bearing soils are properly prepared and treated as recommended in this reportl they will be sui table for the support of .the proposed structur.e.s and the other improv.ements. . This opportunity to be of servic.e is sincerely appreciated. Very truly yours, WILLIA.t-i S. KROOSKOS & ASSOCIATES WSl\:mm Willla-m S. Krooskos ,President RCE ·11318 , -;. • • • • '. • • • • • 'of, • '. ! .• REPORT OF sotL INVE'STIGATION . " . CONDOMINIUM' COMPLEX . SOUTE OF APAMS STREET, NORTH OF AGUA,HEDIONDA LAGOON CARLSBAD, CALIFORNIA Thi,s, repo.rt presepts the .findi,ngs and results of our soil inves- tigation at ',the site of the proposed condominium complex and other contemplated imprOvement~. It is our understanding that th~ proposed structures are to be constr-qcted of conventional type foundations and footings and 'of' standa;r-d type' b'uildingmaterials and n6-t exceeding three stories in height. , . With the above' in: mind, this soil i,nvestigation was unde.rtaken in order to: 1. Cla,ssify the underlying soils. and depths to the various stratas, from existing top of. ground> 2 .. Determine the al,lowable soil b~aring pressures for the natural ground and these same materials used in the compacted fill, based on analysis' o£ shear and consolidatior). tests of the encountered unQ..e.rlying so:tls. . 3. Petermine' the presenc~· apd effect of any expansive soils and. uncompact.ed fill soils that wo-qld cause detrimental damage to pr,-oposed structur~s an4 other appurtenances. 4. Predict ,the. settlement of the natural ground and compacted fill of ,the same m~terial under the proposed structural lo~ds. 5-•. Recortrrnend treatment for areas containing exp~nsi ve soils and ,Uncompacted fill soils. 6. Determine any construction problems that. may develop as a result of the soilcharac,teristics encountered. SITE: The site is l'ocated ea'st of Hoover Stre~t, south of Adams Stxeei;:, ,and north of AgUa Hedionda Lagoon in, the City of'Ca:rlsbad, California. The site occupi.es,.the south.,..facingslope of a large Pleistocene canyon that. is now occupied 'by Agua fIedionda Lagoon. The p'roperty rises relatively steeply from the lagoon to Adams.St:teet, a maximum difference in elevation of approximately -90 feet. An existing sewer main is. located adj a'cent to t1:),e lagoon and runs the ; . •• • • • .' • • • • Page 2 ~ .. . . RElPortof. S.oil·l,:aves·tiga~i9n·., .··~C.6nQ.ominiv.m· ComPlex . : South. c.f Adams,8:tieet, . North cfAgua: Hedionda Lagoon ,'¢ar~sbad, California'. Job No. 72-.3528 entir'e length of·'. t.J;le , pJ,7C?pep:::ty.. Se·veral naturally oCGurrlng wat.eJ:" seepages occur j ttst. above' the sewer main. These seepages 9.re due to. percolating water folloy-ling an impermeable geolQgi,c contact that' e~ist·s in the bluffs 'above th,.e lagoon. Recommend,atlons are made at the back of this' report £ortreatme'ht of th.ese seepages. The s:i te,is prese'ntly undeveloped' e'xcept for a small me·tal-covered building' near the wes:e:ern ,property :J..ine. FIELD EXPLORATIONS: ·Two bor lngs' and ,s'ixteen: bast trenches we:r;e exca va t.ed on: the site, 'specifi,ca:!-ly in the .loc at ion' of the proposedptiildings ~ The " excavations were'loci;l.ted in the fi~ld 'by our engineering'geQ-iogist referring 'to Preiiminary Plap:.by Shuirman-Rogoway &'Assoc;:iates, dated November 16,. 1972. . . The borings and trenc;:hes were excavated into the existing bearing soils· on November 22 and 2A and Decemper6, 1.972, by mean!;) o.f a truck mounted Q.ril=!-rig arid tractor backhoe. .' . The encountered soils from the· excavations wer.e examined continuously: and visually identified during the field operation by our engi.neering", geologist. Undisturbed cq>re samples we):e obtained of the natura,l ground soils by means of a two inch diam.eter IIsplit tube sampler". The sampler is driven in,to, the soil utilizing a 30' inch drop of a 140 pound hammer. A. record of the blow' count i,s made for advancing the sampler 12 inches in.to the natural gro1;lnd soils. The sampler is removed from the ground and the brass rings containing the sampl.ed soils are sealed in air tight plastiC containers and transported . to the labo.ratory for testing. This method of sampling'the natural ground soils is knowh as the standard PenetratioR Test. Boring and Trench Logs were prepared on the ba~is of an ihspec;::tion of the bo.ring excavations and the results are summarized on· the enclosed Figures No. II The nomenclature in' describing the soils is' outlined' in accordance with the Unified Soi],. 'Classification Sy.stem as' illustratea on the' enclosed chart in the back' .of this report,. Soil densities are given as soft, firm, and hard for clays and very loose, loose, medium dense', dense, arid very dense for silts and sands. Soil mQisture ~ontents are descrihed from a range of dry, damp, moist; wet or saturated. EARTH MATERIALS: The earth materials on the site consist of two bedrock formati.ons and four surfiCial deposits. The first bedrock unit is a medium dense to dep.se deposit of Eocene age sandstone·s. The s.econd be.arock unit which overlies ,these soils • • • .. • • • • • • • Report of Soil Investigation Condomini urn Cortlplex South of Adams Street~ N0rth of Agua Hedion~a Lagoon . Carlsbad, Cal-ifornia Page 3 Job No. 72-3528 are Pleistocene terrace deposits consisting of cobble. conglomerate and fine to coarse grained saads. . _ The surficial deposits overlie the bedrock materials described above, an<;l cons-ist of unconsolidated slopewash, qlluvi urn, recent beach terrace deposits, and topsoils. The topsoils generally contain expansive san,dy clays. The alluvium, slope\,yash, and recent beach terrace deposits consist of sands derived from the bedrock formations . LABORATORY TESTS: Laboratory tests were ~erformed on the undisturbed and disturbed soil samples in o;r-der to determine their physical and mechanical properties and their suitability for supporting the proposed structures~ The following labora:tory tests were performed on the s<;3.mpled·soils. 1. Moisture and Dehsity Determinations. 2. Direct S~ear-~estS. 3~ Consolidation TestS. 4. Mechanical Analysis. 5. Expansion. Test. . 'Moisture and Density Determinations: The moisture content a:nd.the dry density of the typical soils ~ere deter~ined to aid i~ the classifica~ion and correlation of the soils and. to obtain some qualitative ~formation reg.ard'ing their strength characteristics. The moisture and density test. results of the sampled soi Is . are shown adj acent to the sample symbols .on the boring logs. Direct Shear Tests: These tests were performed on typical soil samples remolded to 90 percent of maxim urn dry density in oreier to determine the strength 'and supporting capacity of the natural ground soils and these same soils used in the compacted fill., The shear tests were mage with a direct she·ar machine of the 'constant strain type. 'The rate of strain was approximately 0.05 inche!5 per minute. The shear machine is so designed that the tests a.re Performed' wi thout reIT10ving the specimens. from the bras.s rings in which they . . ~iere obtained or remolded thus insuring a: minimum of sampiedis"': turbance. Drainage was p.ermi tted through porous stones that are l'ocated above and below the one ihch high sampie. The.· .. ~amples {:tre sheared' under various normal loads in order to obtain the-angle of internal friction anq the .amou-nt of cohesion. Consolidation Te~ts: Consolidation tests were performed on . 'sel-eci:ed undisturbed samples to. analyze the deformation of the \. ·_·v • •• • • • • • • • • , . .. ,~. "._,,, -. . -:; , ,. , .' . Repqrt Qf So.:Li Investig~tion Condbmini urn ~qofllpl.ex, . . . g·ou·th of Adams Street, . Nbith of Agua Hediond,a .. La.goon Carlsbad, Calif,orhia Page 4 " "". , ", ,." \ '! , .. ' , ~ , ~ • \ '. ~, ',1 . '. ~: ~ soils subj acted to increased loads .. The .conso.lldomete;t:"s lik~.: . the direct shear maChine.are designed to'receive the specimen~ in th~ bra-ss rin.gs· as sampled, thus insliring: a minimum' 9fsample' . disturbance. Poro'gs· stones placed at th~ .. top and bottom 0.£ each specimen,: pe'rmit th:e free flqw of water into or from the sampl'e during the test. '. After the sp.ecimen has: been' placed in the consolidometer and allowed to become compLetely saturated, sl1coessive load increments to the upper s~rface of the soil specimen were applied and the resulting deformations were re.corded at selected time intervals for each increment of loadi,n.g. The loading increme·nt is .maintained on the test specimen until. ·the rate of deformation is rela.tively constant and less than 0.0001 inch per hour~ Mechanical Analysis·: A representative soil sample weigh.:i..ng 10.0' grcimp.was analyzed' for clay content and potential expansivity accordj,.ng to A..S.T.M. 42.2-S4T. The potential ~xpan$ivity arrived from this' tes·t is generally agreed to be a function. of percenta.ge of colloids (fines less than ~OOI mm) . Expansive 'I;'est: Repres.enta ti ve . samples of the pote'ntiallyexpansi ve soils.were prepared for the condUcting of an expansion test. The expansion test was performed in accordance with the requi.rements . ~ ... set forth in Chapter 6' .of the San Diego County Ordinance 2925, Test for Expansive Soils. The results of the expans.~on test are summarized' on ~{gure·No. IX. SOIL BEA.RING VALUE: Results of dire.ct shear tests on samples of the encounteted bearing soils indicate good shea~-res.Lstance . and cohesion properties which is a measure of good bearing support .. utilizing th~ ~ver~ge value of 33 degrees for the angle of ihternal friction and 200 pounds per square foot cohesion with the appropriate Terzaghi Equation, . theh1aximum allowable soil bearing value of these enc'ountered natural ground soils and compacted fill 90ils of these same materials is . at le.ast 2,000 pour).ds· per square.foot. A limiting factor to the above allowable soil bearing value to'be utilized in the desi~n of foo~ings and foundations of the proposed structures is' the qonsolidation of these underlying. bearing soils und~r the structural loads. Consolidation test results of .the undisturbed samples indicate that .'. the bearing .soi1s will se.ttle up to a . maximum of one-half (1/2) ihch: und~r a desiqn load of 2,000 pounds per square foot; Therefore, it is 'our recommendation that the maximqm' allowable soil,' bearing value to be used 'in the. design of foundations and fo'otings ~~ :~ •• _. t • • • • • • • • .' • • Report o,f Soil Investigation Condominium Complex, South of Adams Street, North of Agua Hedionda Lagoon Carlsbad, California PageS Job No. 72-3528 be limited to 2,000 pounds per squp,re foot. This, so:il bearing value may be increased one-thirCl (1/3) for design loads that include wind or seismic analysis~, ~ PASSIVE EARTH PRESSqRE: The passive ea~th pressure of the encountered natur~l ground soils to be used for the design of bui Iding foundations and footings to' resist the lateral forces-is l,)ased on the Rankine Formlil,a and laboratory test results as follows~ l? (Maximum) = 1 wh2x (1 + sin ¢) = 2" -'--(1 -sin 121) where, P -Passive earth pressure we h 2 2 pounds per sq. ft. W = Unit weight of soil = f26 pounds per dUo ft. h = Depth of foundation or footing into the ground -feet 121 = Angle of repose of soil (Angle of Internal Friction)=32° = Equivalent FluidPres8ure = w x (1 + sin ¢) (1 sin 0) (126) x (i + 0.53) = 4l,Opounds cubic ft. (1 -0.53) Since the natural ground soils possess excellent cohesion properties, the passive earth pressure at any depth'shall be based on an equivalent fluid pressur'e of 410 pounds per cubic foo.t. ACTIVE EARTH PRESSU:RE: The a9tive earth pr$ssur~ to be utilized ih the design, of wall,s, etc., shall be 'based on the following formula and the above summarized laboratory tes,t resu,lts. This a:ct~ ve pressure is for level backfill. P (Maximum) = w·'x (1 -si110) (1 + sin 121) = '126 'x (1 Q. 5:n '= 39 pounds per cubic ft. (1 +0.53), Thus, the active: earth pressure at. an'y depth shall be based on an, equivalent f.luid pressure qf 3-9 pounds per cubic foot. FINDINGS AND RECOMM1!!NbATIONS: The following' sun;una-riz'ed finding-s and recommendations are. b<?-,sed :.' .' . ," .~ .. • • • • • • • • .... '.<. :' Report'¢f -80:1:.1 ,Inv.es·tigatiori '. Condominium Complex South oo! AdC\.W$ .street,' , ' No::):"t.h .,0f Agua' H'eqi,bnda Lagoo~ Carlsba,d, Californ.ia Page 6 'on 'the analysis of all the data and info~mation obtained from the soil irivestigatib,n. This includes our visual inspection of the, site, field investigations and laboratory tests'on soils .samples analyz-ed, and our: general knowledg~ and experience with these n~tive soils. " ,.' 'l~The predQrninant bearing soils below the topsoils to a depth o'f 50 fE!'et below the top ofexi'sting ,ground consist of medium grained sandstones· which are non-expansive.. Overlying these sandy soils in some areas, are st;l.ndy clays. These soils ,are exparisi ve, arid, posSeSS' between , five and seven percent sweJl as mea·sured "'by the San Piego county Expansibn Test. , 2. it is 9ur understanding that the site will,be d'eveloped with a " minimum of grading and that the proposed structures will be founded essenti?lllyon the existing natura,l slopes. We, therefore, r.ecommend that all ~con.tinuous foundations and spread footin.gs be e'xtendedthrough the loose' topsoils and at least 18 inohes into the .dense natural ground (bedrock mate-rial,s).. ~hese footings and continuous fou'ndations shall be reinforced f611dwingthe recommendations of the a:t:'chitect or engineer o.f the building pr.og~am . 3. 1;£i t is the intention of ·constructing the proposed spread footings, 'foundatiQns, and cOncrete slabs on the medium expansble t9psoils, then it is recommended that the following work be performed. a. The continuous foundations and spread'footings shall extend' a minimum depth of 18 inches into the firm natural ground or .compacteq fill. The continuous foundations s·hall be rein-. forced witbat least tWQ No., 5 steel b.;:l.rSi one bar, located near' . the top of the foundations and the other bar· near the bottom.' b. ~he ooncrete floor slabs shall be founded oti at least six' inches thick'of non-expansive soils such as on-sit~ silty· sands, ,decomposed granit.e, etc~, or equal, and be reinforced with 6x6 -lOxlO steel wire'mesh. 4. Portions of the site are underlain by uncompacted fill soi~s, ,compressible alluvial soils, r,ecent beach deposits, and· slo.p~wa·sh. It,: is ou;r recommendation that these soils be excavated in the building areas and for a distance of at least ten fee't beyond, their perimeters to a depth of at least fiVe feet below the existing ground grade, or to a depth where firmsoils~re eficountered , a:s approved by the field soil technician;· The, bot.tom 'of the e~cavation shall then be scarified to a depth of 18 inches,· watered to optimum moistur~e content I and compacted to 90 percent of maximum dry density. All trash and other .debris shall oe' segregated from the excavated f1.11 soils and hauled.from the site. The reusable fill soils shall then be replaced and compacted following the,~ttached ~rading Specifications. . I ,·1 .' • • •• • • • • • .' • ~eport of Soil Investigatioh Condominium Complex South of Adams, Street, 'Page 7 North of Agua Hedionda Lagoon Carlsbad, California J'ob N.o. 72-3528 5. The isolated existing areas containing surficial materials on this site which are to'support parking, roadways, and other non-structural improvements shall be prepared in the following manner. ~. The existing fillso~ls and loose natural grDund soils shall be excavated a minimum depth of two feet. Any vegetation, trash, and debris found in the excavate'd fill soils shall be segregated and removed from the site . b. The bottom of thee'Xcavation sha;Ll be scarified a minimum depth of 12 inches ,watered to optimum r'equirements and compacted to at lea$t 90 percent of maximum dry density. c. Th~ reusable excavated fill soils as well as imported fill soils (if iequired) shall be s~read in layers not exceeding eig~t inches in compacted.thickness, watered to optimum requirements and compacted with a heavy duty vij:;)ratory roller to at lec3.st 9b percent of 'maximum dry density. 6'. In the traveling areas and parking areas for automobiles and light trucks, it i.s re,cornrriended that the pavement section consist of at least two inche,sthick of asphalt cQncrete over at least four inches thick of' crus'her run base, de.composed granite (graded) or equal. In areas where heavy trucks load or unload or park, it is, recommended that the pavement section cohsist of either of the following: a. Eight ihches thick of concrete pavement founded on the firm non-expansive compacted natural ground or nOh-expansive compacted fill ground. b. Three inches thick of asphalt concrete founded over at least nine inches thick of crusher run base, decomposed granite (graded) or equal. 7. Compacted fill slopes and cut slopes not ,exceedihg 15 feet .in , he'ight' will be stahle Sit inclinations of 1.5 ho-rizontal to 1.0 vertical. Cut and :l;i),l; slQ-pes of ,greater heights should be analyzed individual,ly'afte.r the"SJ,:rading PL3,n i,$ completed~ . . 8. if imported fill soil$': are . reqtlir~d to' bring the site to grade, they shall'be obtained from an' approved off-site borrow area and. shall be no.n-ex;pansi ve., Non-exp'ansi ve ·soils .;t·re those which hp.ve a li.quid limit less than 30,pexcent; 9-plasticity • < 'index of les's than;. 15 .p:ercentj'an,d a swell less·' than three per- 'c,ent when' 9,ompi;cted to.' a"\: "least ,'~Op.ercen t of maximum dry dens:i ty , ':':and subj·e.o.ted :tQ' a, nO:l;'.maJ,·'load of ,'1 psi. These imported, fill soils shall pe compacted, to at least' "9.0 ,p~rcent 'of maximum dr.y. den$.i ty .. t, • • • • • • • • .' ~ fage B :Rep6r:t;.',6f Soil I,nvesi;:igation Job 'No .:1'2~352,8 ,Gpnd9m~;hi uincomp lex S'out:h of Adams Street, North ,of Ag,u,a Hetl;ionda J,:..ag:oon c:ar lsbad I Cali'forni a .,' , '9., Ace-ording' to the Preliminary Bite Plan, several building,s will be ~06atedadjacent to the existing sewer ~ain along th~ edge of the lag;gon. It is OlJr recommendation that no' foundations lie closer 'tfhcm 15 teet to this easement. If this ,is not possible I we , "recommend that the footings be extended to a depth where no 'sur- ,charge load is placed upon the sewer pipe or backfilled trench soils. ,: io. Severa:I.,,?ater seepages were noted on the site during the inve~­ tig,ation" I.f these' seepages ocCur in the building "areas or ~ 'areas 'where other s',tructural improvements are to be made, then, it will be ne'ces'Sary to insta:1l perforated pipe drains. The d~sign and exact location of these drains will be determined upon' , comple:t;ion of a final site or Grading Plan. The approximate .location. of these seepages are shown on the Plot Plan, Figure No. I. 11. The natural ground soils and the £ill soils when compacted to ~t least 90 peTcent of maximum dry density have the adequate, bearing qualities t.o safely support the, proposed structural loads. The m<'?-ximum allowable soils bearing value to be used in the design of spread footings and continuous foundations ""nich includes all-0'£ the induced loads I dead and live, is 2,,000 pounds per square foot,. This soif. bearing value may be increased one-"third (1/3) ,for design'loads that include wind and/or seismic analysis. 1,2 .. ' S~ttlement of th~ natural groUl1d and compacted fill soils \irlder thepropqsed structural-loads will be in the magnitude o£ one- half (1/2) inch and will be uniform. It is predicted that at , least one-half of the <;l.nticipated settlement will occur during ,,"the, period of, construction. ' 13. In order to minimize the qifferential settlement that cou,ld OC,C'U17 to tne proposed, structures founded in the "daylight areas" or in areas where the 'depth of fill varies greatly from one !'?ide .of ,'the St;.ructUl;:e to the other, it is recommended (but not . requ,ired),tha:t the concrete foundations, footings and floor slabs be reinforced with steel bars and wire mesh resp~ctively, fb;I.low- ing, t.he recommenc;iatibns'of the architect or engineer of the b~ildin9:p~og~am. 14. The ,compacted fill soils that will occur wi thin five fe'et of the proposed ;fill slope will possess poor lateral stability, even though t'hey will be certified to a relative compaction of 90 percerrt of maximum dry de'hsity or better. 'Proposed structur.es a:nd ot,her ,improvements such as walls, fences, patios, sidewa;Lks, ·swi.mming pool, driveways, asphalt pavement; etc., that are located within five feet of the' face o.f compacted fill slope COuld suf'f,er differential movement as a result of the poor lateral stability of 'these soils. 1'5. Founda~ions and footings of the proposed structures, walls, etc . .f • • .' e e, • • ., • •• Report of Soil Investigation Condominium Complex South of Adams Street, North of Agua Hedioncta Lagoon Carlsbad, California Page 9 job No. 72-3528 when founded, five feet and further away from the top of compacted fill slope may be of standard design meeting the requirements of the governing a'gency, aIld designed in conformance with the recom"": mended soii bearing value.' ,If proposed foundations and footings are located closer than five feet inside the top of compacted fiil slope, they shall be deepened'one foot below a 1.5 horizontal to 1.0 v·ertical line proj ec~ed outward and downward from a point five feet ho~izontally inside the top of compacted fill slope. (Refer to F19ure No. XI) , 16: It is recommended that. all non-structural concrete slabs such as patios ,driveways , sidewalks, etC., be founded on at leas't four inches thick of non-expansive soils. 17. No swiffiI\ling ·poo.ls or other subsurface s,tructures shall be constructe¢! in these expansive ,soils, unless their design reflects theseexpan·s-:Lv.e conditions, and are properly reinforced, and in ,general follow the reQommendatiotls' of' the Boils Engineer. 18. Any ~ackfill soils placed in utility trenches or behind retaining ,walls which suppbr't St;.r.Uci;:ures and other improvements such as patiq·s, sidewalks, driveways 1 pavement, etc., (other than:, land- scaping) shall be compacted to at least 90 percent of maximum dry density. 19.' Adequate meClsures shall be undertaken to properly finish grade the site after the structures and the other improvements are in place such that the 'drainage wate,rs from this improved site and the adjClcen.t properties are directed away from the found'ations'" footings r floor slabs and tops' of slopes, via s'urface swales and subsurface drains towards ,the lower level of the site, or to the natural drainage direction for thi,$, area. Proper surface and subsurf:a;ce dr'aina,g'e wili insure that no w:aters will seek tpe level of the' bearing SGi.ls under the foundations, footings ,and' .. floor slabs. ~hich coul-d result in unde.rmini;ng and dif';ferehti.al settlement or uplift to the structures and' ·the other;Lmp.rovements~ 2()~ PIa'nter bci~es adjacent t·o the building foundations shall be ,coD'structeSi ,wi til 9. ,grave,l base and/or drain with, the direction of ,drainage water, -away. -from 'the building foundations, footii}gs and floor .slabs ,to the, ;;treetor the lower level of the site. 2,1. 'l;'he passiv~, earth pres$ure to pe used for the' design 'of fOl,1ndat,j.on$ .andf00tin~rs., to. r;6$ist the lat.eral forces (wind or seismicLshall , ,be, bqsed on an eq1Jivaleht fluid pressure of 410: pounds per ci;1bic ' foot'. The a~t,ive earth pres'sure: for the. use and desig'n of found·a.,-, tions, wal:L$ ~ ,et,c~ i ~hall ,be based. ',on, an equival,ent flt!lid pressu;t,e 'of 39 pO\lnds pel;7.C1Jbic .:foot. '(level"backfill) , . -'. . . A coer£ic.ient of frictfo!J.., may 'be 'use~ ,betw,e~n tbe ,;80il and, th~ ~ • '. '. '~*"\'\I ,," • J~ I: . .. ,.,' . • .r .' '.:'. ' • .' • •• •• • Re.port ·of· Soii Investigation' Condominium Complex . , S!Outh of "Ad~s' Street, ',No·rt:h of ·A~,U:a H:~dipnda. Lagoon Cctl;"lsbad, California . .~ . ~~ ... Pa,ge· .10 Job No. 7Z-3528 concrete f01;l:ndations'and floo+, slabs ·on a factor 0:£ '0.4 times. the dead load. This value meri .be used in, conjunction with the " passiveeart0-pres'l;?ure in, dete:rmil'1ing the laterai -re&istance· o,f the comp~cted fill soils and the natural ground soilS. GRADING SPECIFICATIONS:. ,The grading oper'ation shCill be performed in aGcordanc~ with the .enGlosed "Grading SpeG:i;fica.tions'!, a·ttachmeht l,aho. with the .. ' general requirements 6£ the City of Carlsbad and the summarized 'r~commendattons in this report. The fill materials spall be tested by members of our f'irm to insure tha·t they were compacted'to at least 90 percent of maximum dry d'ensity. Upoh completion of; the grCiQ.ing ope~ation a Report of Certifi·cation of Compact.e¢l. Fill will be prepared hy our firm and a copy filed with the: R~.sident Engineer of the City of Carlsbad. LIMI.TATIONS: . Th$ 'recommendations sUI\!ffiariz.ed in this. report are based on the evidence obtaj.ned f.rom ·the boring excavations, . laboratory tests of the typical' bearing soils, examination of the site by our engineering geologist and soi.ls engineer and experience with the soils that are native to this si,te. Uni.formity of the soils has bee~ assumed between ,the borings that were excav~ ted. ',', Dl:1ii.ng·,. the grading.' operation, qualified perso·nnelfrom our firm perfori\1 an ihspectiona£ the underlying soils to'substantiate the findings .!=l-nd recommendations as ,outlined in our report:., If any irregulari ties are o.bserved, specific action will be ui1;dertak~n to :provide an adequate remedy . It is the. re-sponsibili ty' ,Of the owner and/or .the devel.oper to ini?ure .t::hq:tths: recommendations summarized in this report are carried out in the field operation. This report and,all subsequent reports./and addendurns automatically. become a par~ of the b~ilding spec~fications~ if' you h~ve p.~hy. que:stlon,s donc~rning this report I please do not hesitate to call us. W8K:mm (5) En,closu;res Respec-t'fully 'submi tted, ~VILLI.¢v,f S .. KROOSKOS' & ASS-OCIATES william S. RCE. 11318 Krooskos, President " • .. • • • • • •• • • • BORl N'G S UMM A Ft.Y" ',S:HEET Boring No. -±-E'le,v,ofi o.n , __ ' o ,;:.:.0 . l V77A\ Med. dense, damp, brow,rl# ,fine to roed. ~\ sand and some cobble (S·P) 'TO~SOIL--:f . "'!\ Soft, moist, gray-brown, cl.ay 5 "'" (cL) " - 10 -0 Dense, damp, tan., fine to cO?lrse sand '" 15 .. ,,~' " .. .20... . ~~~:--::--Dense, damp, gray-black, very fine :, \ S,il ty sand (8M) -~---.. ----..,.....,.---- 25 ..... . 30 - 35- - ~ 40~ . ' . .! . . , ,', i . . Dense, dantp, tan" f.ine t'o med., sand (SP) " pense, damp, gray-black, very fine 4' • 1\ silty san,d (SH) I 45 -, ~ ~ \. ___ ...... , _________ ~ __ --..,...,.........-'. _-'---.......... ----l ! I?epse .. , damp, tan', fine to med.l t ,. ' sand /7 B.ot.tom of Hole,-I Jr LE,G,'EN 0 (D Un.disJurbed Sample !' Water Ta,bJe ,l:Jnified Soi I ©, D! s tu rb e d S ci m p Ie (S M ) C I a ss Hi c'ot,j on ' t 117 117 4.3 1.3 17 '-~ Job No. 72--3528 Figure II • • • • • • • • • • • "ORING SUMMARY SHEET Borl og N.o. ~ E leva tl on U . <>" •• . ~.-:--:-: >,Med. dense t : ", ... \c layey sand moist, dark bt'OWT1, I I and some cobble (Sc) TOP8L, . t f 5-'.' -\Med; qer..se, damp, light gray-brown, 1 . r<" '~ layey -s._a_n_d __ ( 8_C_)_~ ______ " ___ "":"~_1 j .. '. Dense, damp, tan I fine to med. sand .10 ~ . {SF} '. ·1 l;; .... r-:-_~-r=.. . ---..--____ . __ ~~~.--------I _ L. " Dense, damp, tan, fine "CO med. to . ' .. ' _ coarse sand (SP) J":-:., .. '--~1 20-'.~~''-I\ 'Densel d(lmp, gray-black, silty sand l' -••. ' > I \ (8M) I o 0,' '--,-..,.,...... ___ ........... _____ . _____ ~-~ ___ _ , .. . . " , I Dense, damp, tap, fine to med. to coa.rse sand (SP) LEGEND I f I t I f, .. , .- CD Und·Isturbed -·S ample ©. Di·st.urbed Sample ~ . Water Table Unifie,d Soi'! C1.dSSlfi ca.ti on . Job No; 72-,.)528 Figure III (SM) I i 1 ! t J 1 I l j f i < 1 1 1 1 1 1 1 1 • 1 1 1 1 1 1 1 1 1 J 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 '1 \1 1 1 1 1 .1 .1 1 1 1 1 • • • • • 140 \ so.il Type I . Classification-T.an PiI e 1\ to Coarse Sand .\ Boring N.o. 1, Depth 1< 1\ \ 130 /, / \ \ \ 1\ 'H .\ 0 120 . I.J 1\ .jJ \ f!. -~ [\ Q) \ 3: .jJ L\ -.-4 \ .:: .0 \ . ~ \ p .. !\ t\ . \ tJl . .:: -,..{ UJ UJ n:l Cl.. 110 100 "-,.r\ .jJ m u ~ . ' \ Q) Cl< 90 T\ I\. , ~ 80 Moisture Content % 1 10 20. 30 40 LABORATORY COMPACTION TEST Maximum Dry Density 127 pef Optimum Moisture Content 9.8 % • • .jJ ~ Q48 . ~ ~ " W a 6 ~ . -.-4 \~ Ul 0.4 fJ:1 Q) 1-1 .jJ CIJ 0 • .2 1-1 cO Q) .c:: U) o 100 90 80 , 70 . 60 50 40 30 20 10 o 1000 • • •• • • DIRECT SHEAR TEST' , " . " V ... '. ~. ./ , v/ /' ~ 1/ r /, V. , . .. Jj. I IF ngle. of,' nternal riction = 33. 0.2 0.4 D.6 0.8 1.0' 1.2 Normal P~esaure, .Kips/Sq.Pt. MECHANIC1\L ANALYSIS .' '3," 3 '4 ·4 10 ,4Q 200 "-'. , .. ' i ',=, . ' \ \. .\ \ '. i, ~, .,. ... .' " \'; . .. ' '-'I .\ .~l:::::::::..:. 1,00 10 1.·0 .05 ".005' .• 001 \.' Graih Size in Millime~ers. .' I &c~~~;:~s; Ie t:ni F Imt ICla{ FILL .SU:J;TABIJ:,I1;'Y "'rESTS Job ·No. 72-3528 FIGtmE' NO ~-YJ:i:ht . ' • 140 130 120 110 LOO 90 BO •• • • • '\ Soil Type'!I Classi.ficatiol1.'"'"Brown si;Lty Sand r\ '" " T~~nch No.9, Depth 1 ~ .. \ 1\ " / v \1\ 0 :\ I-J \ 1\ +l \ .c: ' , Cl 1\ .,-i <U ~ , \ +l 1\ .,-i . \ s:: :::> -. f\ , ? \ .~ 0 II 1\: r\ " . ,,\ r\. " \ ; ., .-r,10istur~ C()nt:~Iit % 10 20 30' LABORATORYCOM,PACTIGNTEST Maximum D~Y ,.Dens,ity 122, pcf OP:t:imumMoisture Content .;;;1=2"--_ % 1'\ ~ ),. Tl 40 tn s:: ''-; Ul Ul ro p. +l s:: (1), u ~ (1) p. • +l ~ (J1 Cfl ~ Ul 0.. .,-i ~ Ul (J) (1) ~ +l Cfl ~ ((j (1) .c U:l LOO 9Q 80 70 60 50 40 30 , 20 10 Q.B 0.6 0.4 0.2. o o 1000 .' , . /' ~--~- • • DIRECT SHEAR TEST v- ,/' ./' , . / / / '1 ! • • Angle of Internal Friction= 300 0.2 0.4 0.6 0.8 1.0 1.2 Normal Pressure, Kips/Sq.Ft. MECHANICAL ANALYSIS j"j/4, ,,q lU' 4U LUU '" .', ' , "", \, \ \ \ i \: f\ ,'" "" r-.... 100 10 1.0 .05 .005 .001 Grain Size in Mil1imeters IC~bbles I Sand I Silt I Cla~ . & Gra,vels C' I '~ IF. '_ . FILL ,SUITABILITY TESTS Job No. 72-3528 FIGURE NO. VI.II Ie 140 130 120 , 110 100 90 80 '.' • • \ • • .j.J ~ 0' tI) .' .' • • • DIRECT SHEAR TEST 0.81 I I I I lEI II 1'1 $oil Type III 1\ C1assif ic'atiorl-Brow "'-til P. l: Sandv'~ _t ~ Q .61 II Ufi I I I III Angl'e"'of rnt.ernal ,Friction= 27 , Clay % r\ Tr1'?l1ch 4, Depth 11 \ Percent. SWell = 5.1' \ \ ~ 0 \ \.l V , ~ .j.J \ \ .c: .~ 1\ ,(1) '\ ~ ..-, , .j.J r\ -M \ C p 1\ ~ b ,1\ r\ ' \ " 1\ " "-~ l~isture Content % ' 'f ') ~ 10 20 30 40 ~BORATORYCOMPACTION~EST Maximum Dry Density 118 'f ' pc Optimum Moisture Content 13 % tTl C -rl Ul !J) -m 0.. +l C Q) 0 !--l Q) Cl.i til Ul (1) !--l .j.J en !--l rtl Q) .c: Cf) 100 90 80 70 60 50' 40 30 20 10 v 0'. 4 Jz 1 I I I I I I II'·'. I I 0.2 o ""I 0.2 0.4 0.6 0.8 1.0 1.2 Normal Pressure, Kips/Sq.Ft. MECHANICALANALYSlS --.,..--- , -----~ "" \ \' ~, .~. ""' I---- o 1000 100 10 1.0 , - .05 .005 .001 Grain S.ize in Mi.l1imeters [--CObbleS 1 Sand. I silt I claj & Gr a ve 1 sci M I ' F " " , FILL SUITABILITi T~~TS JOQ No. 72-3528 . FIGURE NO. IX I I • • • • • • • • e .. ' • . '---:' ·;:'.~r...... • C D N SOL IDA T ION -~ R £ S SUR E CUR V E 'Normal Pressure -Lbs./Sq.Ft. 0 0 0 0 0 0 0 0 0 ,0 0 a 0 0> 0 0 0 <;:> 0 0 0 0 0 0 o· 6 0 0 0 0 0 0 0 ..--' N C"") o::T U"> N (V') o::T LD r-N .- <V ~ I 'I ~. . I I I I I I I I I 1 .! : T.-.. , ____ I I ' , l. _ ' ' --.... '-..... ~--, ---I I 1 ' ':l I V) ~ a I ~< I----r---:---r;-I I I : r---~ :--'---r-,.,. , " I '---... ; i"--~ t--I ----. I . I , ' , "I:,' I -...... f-. t--l I 1 I ~, i--,,'~~ I r::::::::: --:---I I f_ ,,",_, ' T I, . , """: -+ .. _:..._., 't--. ' ' 'I ~-, ' I Bor~n' I " ~ .... --I [~,-I r---' ! I. ~ I ---~ I t--- I r' --f-., -=f'--:-~ , I -~ ~ 1 ~1""-f------r---..I Borin~ 1 I +l 2 s::: OJ u s... OJ 3 a.. : ' ,I I ~ I I , "" ' , I . I I 1 "',-: I J 1 "-,I I I· I, I' },. ' I I I -, 'I 1 I 1 I ! '-, r, I Trend j I r---i:-. ~ : --------.-~-"I .. ~I remo.iC .1 ~ , i 1- I ". , I I ! I I .: s::: 4 0 -r- ~ to "1:) 5 0 VI s::: 6 0 w I I I I 'I 'I I I I I I i: I ' I J 7 I . I ! : J .-'I' \. I I , i I I T J' I I I 1 8 I I I T Ii ! " I : I . 1 I 'I , I 9 I i ( : I; l 10 WILLIAM S. -KROOSKOS & ASSOClATES . " 1, I, 3, W D epth 10 D epth 16 D epth 2 I 90% Job No. 72-3528', F l' 9 u r'e No. :X\ . '. ' . • • . proposea S~ruct,ure ~ concrete Fl,oor Slab 5'-0" .. '. .'." ., ~ --:0----:-;-; .... ..... , "- , - Reinforcement of . Foundations and Floor Slab~-' -', 'followi,ng the recommendations - of the Architect or Structural- E~gi:neer 'C,onc·rete Foundation / • Comppcted TYPICAL· • • Top of Compacted Pill 5:lope ·1.~nim~lIn ~ SECTION . ' • • Compacted Fill Slope Maximum Inclination 1.5 : 1.0 -5"-6~ ~ .. ~ ( Showing proposed Foupdation Located Within Five Feet of. Top of Compacted Fill Slope) . ... " Job ·No. 72-3528 FiClu~e No. X[ ':.: • .... -". ~ ~ -~ ........ t.. f~ ~ ~ '/;.... ..~ '.. ,':!,.! .... '.,. ,.' .>-• : • .. j • ", ":":<' " ' ,> " ,:, ,', , ,<' ' .> ,::, " A,tta,chm¢,h:t 1. . ~~ :~";:,, ;;'.:, . ; ;')J ;.;~ : .J:,;, .. '....... .' .' , )?<:>.>J e '.).',;' : ,~~,~,j ,::;:.' -.' • ' r ::<'?,'" ,':.~ '~,' ... ~':~~~~';;~" ... GE~rrr'NG' S,P.ECIFISA'fJ;'OW~ ",' ':, . . .' '0, .' .,... .' ' • . ". ,: "':, '··-G'ElN:E.IB~~.:·\-': :The' ~ntent Q£' ,this item is to .p~Gperly· ~-stablislJl procec,lu~,~·.$.:-, . , .. ' tot';: . &;L;e'i;I.l:ing / __ . compacting natural. ground,. preparing ,:areas to' be. fi.l~~d~,", • ':) ". ':·'~~h'ct':;p).,~c,ing· an9. c6mpa¢ting fillm~terial to, the g:t~d~s a.l\d sl.Qp~s a:s':' '.: , " ',./ .:··s~qwn,·'o.n .tl:(e appl;'oved ·plan,s. ' " ':. " . )" , . '. -.... ~ " ~. . . -' . : .!'" ~ • !, ~ . ~ '> _ • _. ..?£' 4 _ ,:.";; ,,' . ,,'. C~E~J:NG:·· ~J:l veg~tation,.' brpsh anq 'd'ebris, s];lall be remove.d, piled",. , " "./' ,arid' burnea ,qrotherwise' dispos'ed of to, giv:e tbe' surface a' ne,a,tand .' "~,'." "., ... '~ ;finish~d app~·aranoe.,' '.::::, ':: . ',,; ... ', ' , .', '. ,'.' '. '. . "; /." OOMPACTlNG NATURAL GROUND,: After clearing,' th~ natural grdt,lnd'~?"hC'l-i.i· .-, "" be' 'scatified' to' a 'dep,th df at lea.st 12, ipches I' watered to .optim~m " ';' .' ,l;eqU'irem.eht,s ,and compact~d to ncit less ih~p 90' per9'ertt of· maximum .<iry . , d:en$.,i 1:1, '~c90rd~n.g· to. A. S·. T .M. 'T'e s t ~1etho4" DIS 5 7 ;i.I:j.a· fotlrj,nc)i 'd'La:-. ",' ' , ... ",: mete~ cyl-;Lndrical Indid of 1/30th cubic' ;foot Volume,.' Field. de.ns.ity' tests -•. ,,·:./,-·;:~s,hall pe ,taken' in the natural grou:nq in accordance' with A.~,S:T,.M. Test' . Method, D 155·6: . , . . '/ : . '. . J;ILL "MATERIALS:' Mq,teria,ls for ·the fil·l shallbe approved by:the '. spil& , :'~ .. ~eng.in~er.,aho.shall 'be fr.ee ,from veget.abl'e matter and other deleterid.us supstances'.. In t.he event that expansive tna:terialsare encountered' :w-ith;i..nb\To. fE?etof' finish grade theysnatl 'be . either entir~,ly' retno-v:ed ' .. or ·t~.brbugbly mixed with good grap.ular· mC,1terial before, incorpotatirig .'. " t.heitl' in' fi.l-ls. No footing .$hail be allowed to pear on' soils 'which in'.: the~pj,i;li,on of the soils, engineer are d:etrimenta1.1yexpansive'l '~nle:ss, desi.gneQ:. f,or-·thi.s cl,ayey 'condition ." . :.' .. l· '.1 I I, I, . !: ') . '. PLAciNG 'AND COMPACTING FILL 'MATERIAL: After preparing, the a.r;"easto: . ~~e::f,;i.l,~.ed,; the ,fill materialsshal'l' be plaoed in .layers not to ~xceed: ... ' ': 'six, .;i,.1;iches in compacted. thickness. RaCfl layer shall. be watered to " optimu.m" ,;requirements a·nd compac.ted to not less: tha'n .90 percent o,f • • . ';0. roaxtmUrtl d;ry density in 'aqcordance with A. S. T. M. Test Methad·'D 15'57.' 'Compa.c,tion 'Qf the fill 'shall then proceed in the specified: manner' ,. ,to 'i;He grad~$ ~$ shown an the aPl?+,oved plans. ' , 'Whe'n: the s.:tope ratio O'f the o.rigina.l g,round is steeper than fiv~:hor.:.. izoi'i-tal to· o-rj.e vertical, the original, ground shall be steeped or : l;>enched·. GToi.:!,nd slopes flat.te;r th:arifive horizontal t6 one vertical' ~rhal~l be beil.c:hed when cons,idere¢t necess,ary by the-Soils Engineer. _ ' ,Fill-'slopes, $hal,l ,be compacted. by meahs of sheepstoot ro,ller ..or other ;'S:u;i.table _~guipment. Slope Gompact:ion $hq,ll be, continued until the' . "~ , s:lqpes are, stable, but not too den-se forplanting~ " .. ~ '" '-'·Field. density' tests sha.ll be' t~ken when Qohsidered necessary by the, '.' ,'soils ,engineer. in ·accorda·nce wtth lLS.T.M. Test Method D 1556 and shall . be ,1t!a,de'r not exceeding two: feet in vertical heigh·t, providing ,each .J::ayer is t~st;ed. " S(JPE~VISIQN:' ContinuOJ,ls superv'ision of tne fill shall .be made by ·the ·.repregent~tive of William S .:. Kroosk.os & Associa::-es <;luring'the' gJ:a:d~ng ope:ration so t:hat he can certify that the f~ll was plaeed in a.cco~<;lance with these specifications. . 1· . 'j ': . ; '; .,' -~ ..... .. , J '\ "SEASON LIMITS: ~O fill material..,. shall be placed,' spread or rol~ed during, un;fi:rvor;;ibLe weat,her' cOl1di tions. When' the work is interrupted by heavy , r.ain, the filling operation shall not be resum~d until field· 'tests ' ' . iuclicq.te· 'tilat the moisture content and density of the fill are as 1 , previou,~i'y· specified. •• • •• • • • • .. ~ " , .' . .··.r >' ' ~ . ~ : •...... : -:;,.' .. ~ '. . I .' .. ,< • UNIFIED SOIL, C.LA,SSIFIC,ATIONCHART· SQ;IL DESCR;IPTION G~OUP.SYMBOL ~Y1?IC~L'l'1~MES COARSE G.RA'1;NED More than '·h..;:tlf of material is larger . than a No. 2,00 s·ieve • dRAV~LS CLEAN G~VELS MO.re than half of· Coa-rse. fraction is larger than No.:.4 sieve size but $mal1er them ,3". GRAVELS WXTH F:LNES (,Appreciable ':amount) SAN'ElS. C+.sEAN SANDS More than half of' coarse fractiop' is $rnaller thah a NO. 4 sieve· SANDS WI'TH 'FINES '(Appr~ciable amoun·t) F:tNE GRAINED More than hali 6f m~t~rlalis " sr,na],.ler than a ·No. 200 . SILTS' AND CLAYS' Liquc:i,d Linl'~t l·ess. than 5:0 -'.-'--'-" . . L1 quid' .'L,iI!li,t gr~ater bhari .. 50 -,'. -... , ' HI~HLY'qRGANIq.SOILS . ", ,', ,l ',' . . . ~ , k'.~'" ! .' sieve. GW GP GM '. GC sw 'sp SM,' SC ML CL OL Clf OR . PT' 'Well graded gravels, gravel and ~arid mixtures, ritfle. or no fines. Poorly grCl.ded gravels, . gravel ,and'sand 'mixtur~s, .little·or no fines.' Silty.gravels, poorly. graded gravel-sand-sllt mixtures,. CICl.xey,gravels, poorly grad~<l gravel-sand-clay mixtur:es. Wel.l graded s,anq, gravelly sC\.nds, little. or no fines. , Poorly .graded sands, gravelly' sands, little or rio fines. Silty, sands, 'poqrly graded .sand and silty mixtures. C).ayey sanQ:s, poorly gr.a.d.ed.,· sand ·and ciay mixture~. Inorgani.c silts and very fine sands, roc:k flour ,. ... sanqy s·ilt or c:).ayey .... s;i.J,t S2lDd mixtures with·sJ,.ight plasticity... ,,:i::norqanic clays .or l<?t ;t;Q ' ... M'edium plasticity, gravel1y clays', s.i;wdy ;cl.ays·"" ~iJ:t:y:-:: ' .. clays, lea,n clays .. ' , ' ' . .'Organic .si;tt;s ·.and ~:)l;gar:lic' .' .'." sil ty clays-o'f lo~t , ... '. . :' , ~ ,.p.Ul;$tici ty. ' :. . .'" : . I.~9,;r"ga·n·±c'silt:s, ·~micace6us; .. ':: . ,.' . <Q.r· diat9mace~),\.1s· fip.e' s'a::gdy' . '.' . ''.-p:r' sil.,t.y soi1s.#: ·ela<$'tic· . ' .. ,: ' sil. i;:s.. . , , ...... i •• - .' " , Inorgan,:Lc cJaY·'S· .. of. h.igh .: . pla~'tici ty, . fa,t c~t?tX s ~.' ..., ~-'-.... ..' . . Qr'ga:hic c.1ays of' ·medium· to .. _. h?-,gh plas,t,icity. ' . p,eat. qnd' other highl,y· . ·orgqni.c .. so.ils'. .' . ,". " -." " '. WJ.:LLlk.l'1. S.' l{ROO.8KOS .& ,A,SSOCIATES, : . Soil and FQundatiojl~ :'~ngine,e-rs, ,'. , {-!., ~ . -.-~ .. ..' .~~-:~ .. ~ ~