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Home My WebLink AboutSubsoils Study for Foundation Design.-H l*k¡tr,1 1¡¡1'r- ¡:t u.la k i. irl¡r ct- lrn j,^-,¡ 1. j lrt 5û2'l 1...r:,unrl Rr.r¡¡¡i i -1-¡ {-,ilr¡ rrr',¡i,.1 Sl.rirrgo. t'r ¡['r : u.ì,r ¡i I 6û I I''i ror¡e: 9?l't-945 " ?!l8S Frrrr 97tl-!14-5"8454 e¡n¡il: hl:geilirrhpge*tecir.conr HËFWÕITTH - PAWLAK 6HOTEçHNITAL SUBSÛIL STÍIIiV FOR FOT'NDATION DESIGN PROPOSED RNSIDENCT AND DETACIIED GA,RAGE LOT 2, CÛULTER CREEK RANCH GARFIELÐ COUNTY, COLûRÄDO JOB NCI. N7 OO75 MARCH t9,2007 PREPAPJÐ} FOR: JOHN MOORE C/O LaBARON 4 BARS, LLC P.O. BOX 92940 SOUTITLAKE, TEXAS 7 6092 Pr'1..t:r lrll-S4l Tllt) r Crrlrrr.¿r.1. lìir¡-i'tr 7lr)-(.31,55í.,1 s Sil'er.rh(]'rr 970_46S,lq,Sg TABLE OF CONTtrNTS PURPOSE AND SCOPE OF S]'UDY.,... PROPOSED CONSTRUCTION....... SITE COND]TIONS...... FIELD ËXPLORAT]ON SUBSURFACE CONDI'TI ON S. FOLINDATI ON TìEAR]NG CONDITI ON S DESIGN RECOMMENDATIONS.....,...........,.. FOT'NDATIONS.....,^. FOL'NDATION AND RË'IAININC WALI,S FLOOR SLABS LINDERDRAIN SYSTEM.............. SITE GRADING SURFACE DRAINAGE ............... LIMI'TATIONS FIGURË I - LOCATION OF EXPLORATORY BOR]NGS FIGURE 2 - LOGS OF EXPLORA ORY BORINGS FIGURE 3 - LEGEND AND NO]'ES ITIGURES 4 through 6 - SV/ELI,-CONSOLIDATION TESI" RESUL,TS TABLE I- SUMMAITY OF LABORATORY TEST RESULI"S -t a 1-L' aJ- -3 - 4 4 5 {t 7 8 9 - l0 - PURPOSE ANÐ SCCPE OF STT,II}Y 1"his report presents the results of a subsoil sTudy ibr a proposed resiclence ancl iletachecj garage to be located on Lot 2, Coulter Creek Ranch, Garfielci County, Colorado. 'I^he project site is shown on lrigure l. T'hepuÌpose of the study r.vas to cjevelop recommendations fbr foundation design. The study was conductecl in accordance r¡ith otlr proposal for geotechnicäl engineering se rvices to John JVioore, clated Janu¡u-y 23^ ¿UU /. A field exploratiorl prograrx consisting of exploratory borings was co¡icluctecl ro obrain inlotmatinn o¡l subsurface conditions. Sanrples of the sLrbsoils obtainecl clLrring the 1ìelcl exploration were lesteci in the laboratory 1o cletel:rnine their classiJlcatioî1, cornpr.essibilitl, or swell and other engineering ch¿tracterisrics. '1'he resulrs of the lìelcJ exploration anci laboratory testing rvere analyzed to develop recommendations I'or founclation types" depths ancl allowable pressures fbr the proposeci buiÌcling fbr-¡nclaiic¡ns. I'his report summarizes thc clata obtainecl dr,rrirrg this stucly ancl presents our conclusions, clesign recommendations a¡lc1 other geclteclrnicai engineeling consiclcrations basecl on the proposed constrllcti on an cl the subsurlirce conditi olls encou¡rtered. PROPOSED CONSTRUCTIC}N 1-he proposed residence will consist t)1'a one ancl trvo sto¡y. heavy timber strlìcture over ¿ì crar,vlspace r.vjth an attached garage localed in thc aica cf'l3oríngs I tliir.rügh 4 as sliown on lrigure L A separate detachecl garage lvith a socl coverecl roof will be locatecl west ol' the resicjence in the area of ]Joring 5. We unclerst¿rncl lhat grading fbr rhe struciures will involve maximum cut anc'l fìll clepths of about 7 feelwith respect io the existing grouncl surface. Typical fbundation loads provided by Datum lJngineers" Inc. wiìl range fiom 2.5 to 7.5 kips per linear foot for r¿'alls and l 0 to 60 kips for columns ollvhich 65 perccpt is pennanent dead loaeJ. Job No. 107 0075 l-t 15G€ólech 5 If building loadings, location or grading plans are signilicantly cli{I'erent f}o¡n those described above, we should be notified to re-evaluate the recommenclations contained i¡r this report. SITE CÛNDITIONS 'fhesitewâsvâcantandcoveredrvithuptoairout 1t/zlêetof'snorvatthetimeol-ourlleld exploration. The grourtd surlace is relatively flat with a strong to ntoderately steep slope down to the e¿rst and northeast at gracles between abour l0 to 20 percent. T'here is about l5 feet of elevalion difierence ecross the pnrposecl ¡esidence fbotprin\and al¡or.l1 25 fèet across the proposeci clevelopment area. Irrigation ditchcs are located to tirc tvest and through the centerol'the proposerl building site. Vegetation co¡rsists of'mairrly grass ancl r,r,eeds with scattered clusters of oak brush and sonle juniper lrees. FIELD EXPLORATION The fieid exploration f'or the project was conductecl on lìebruary 15, 2007. Irive explor¿ìtory borings were clrillccl at the locarions shor.r,¡ì on irigure I to evaluate the sLlbsurfàce conclitions. Tlre borings lverc aclvancecl with a 4-ìnci: diameter continuous flight auger powerecl b¡, a remotc o¡;eietted, tiack-rnou¡tecl Civfll-5 SL,CßAC drill rig. 'l'he borings r.vere loggecl by a represent¿ìtive of I'lepwortil-Pawiak Ceotechnicai, lnc. Samples of the subsoils were taken rvith l% inch ancl2 inch Ll). spoon sarnpiers. 'I'he samplers r,vere clriven into the subsoils at various depths with blows .û'om a 140 pound ham¡ner fàliing 30 inches, 'l-his tcst is sinli.lar to the stanclarel penetration test eiesc¡berj by ASTM Metlrocl D-1586. The penetration resistance values ai'e an indication of the relative density or consistency of the subsoils. Depths at lvhich the samples r,vere taken and the penetration resistance values are shown on the Logs of Exploratoly Borings, Fignre 2. The satrples were re tunrecl to our latroratory lor revierv by the project engineer anc{ testing. Job No 107 0075 HÞGeibtech -)- SUBSURT'ÂCE CONDITIONS Graphic logs of the subsurfäce conditions encounteiecl at the site are shown on Figure 2. Below about i foot of organic topsoil, fhe subsoils generally consist of slightly sandy to sandy clay down to the maximum exploreei depth of 43 feet ai Boring 4. Scartered sanciy gravel lenses containing cobbles and possible boulciers tveîe encountcrecl with depth in the borings. Practical drilìing refisal wâs encountered at a clepth of 43 feet ar lSoring 4. The ciay soils possess â¡t expansion potenliai when wetted. Laboratcry testing perfìrrrried on sanrpies olrtained dr:ring tire fielcl exploration includecl natural moisture contenl, density, percent finer than No. 200 sieve (silt ancl clay fi.action) gradation analyses and Atterberg limits. Swell-consoliclation testing r.vas per{'orrnecl 6n relatively r"rndistLlrbed clrive samples oJ'the clay subsoils. The srvell-consolidation tesr results, presentecl on Figures 4 through ó, i¡rdicate lorv compres,sibiliiy uncler relatively light surcirarge loading ancl a moderate to high expansion potential rvhen wettecl under a constanl light sr-rrcharge. Sweliing pressures ranged between about 3,000 to 20,000 psf. Atterberg limits values fbr sarnples of the deeper clay soils inclicate n:ediunr to high plasticity. 'fhe laboratory resling is su¡rmarizecl in l'able l. No 1'ree water was encolìnterecl i¡l the borings at the time of clriJling ancl the subsoils rveîe slightly moist to moist. Grotrnciwaler levei is expectecl to be reiativeiy deep, ireior.r, the depth of'the borings. F'OUNDATION tsEARING CONDITIONS The subsoils encr:untered at úe site possess low tr¡ high expansion potential when wenecl. 'I'he swelli¡lg presslx^es overall are too high ro be nritigateci by loacl concentratio¡ o¡ sliallow spread fcrotings to reduce o¡ prevent fbundation movemerit in the event ol'wetti¡g below the founclation level. Cjrouncl nrodificatìon by removal of seve¡al fèet of expansive soils below the builclings does not seenl practical at the site due 1o the clepth of the expansive soils anci the need f'or intported grairular structural fìll. 1¡r our opinion- .lob No. lt)7 007.5 Cecbtectr 4 suppûrting the buildings on a cleep f'oundation, such as driilecl piers or lteavy cluty helical piles, wirich extends down into a stable (non-active) moisture zone shoulc'l prcivide tnoderate loacl capacity and relatively low risk of post-construction founclation lnovement A post-tensioned siab founclation bearing or1 several feet olmoisture treatecl, on-site clay soils could be usecl for supporl r¡f'the cletachecl galage. Spreacl lootings beari¡g o¡ the clay soils may be feasible for minor structures, such as retaining walls or other ¡o¡- nlovement sensitive stl'Ltctures, provided that the risk of movcmenl ancl clistress is acceptabic to the owrìcr. DESIGN RECOMMENDATIONS FOUNT)A1'IONS Consiclering the expansion potenlial of the clay soils cr'ìcounterecl in the borings ancl nature oltheproposed construction, we recolntncnd rhe residence and garage be founcled with a "screwpile" foundation that extends clonn into ¿r stable (non-active)moisture z'one. A"screwpile"f'or-rnclationsystemisaheavydr"rtyheìicalpiìingthathasbeenusecl in the l)enver area to rcsist heaving due lo expansive soiìs. Screw pilcs are curÌ-ently i:rrovidecl tCI lhe Westem Slopc by Alpinc .Site Selvices" Jnc. (303-42û-A048). 'l.he acrivc nloistllre variation cleptir should be taken as at ieast 20 lèet ancl we expect the piles rvill need to be at ieast 30 feet long tc acliieve the desirei,l íinclrorage, biit Aìpine Sitc Scrviccs shor-rlci be contactecl tor specifìc loaclilrg anrl ile.sign inlbrniation. We expeci allowabje pile ìoad capacity io be on the orcler of 75 kips. Pre -clrilling rlay be needed to ¿rchieve rhc minimum pile depth due to rocks. A void fbrm ai least 4 ìnches thicl< should be plovidecl below gracie beams ancl at least ó inches rhick below reinlbrced corìcr.ete stmctr:ral slabs lo prevertl r-rplift crl'the l-oundaticrn in the event of subgr"ade he.?''.,e. Test pi.les shouìd be installed to further evaluate the suitability of the screw piìes at the site. Basecl on Ihe subsoil profile ancl our previous expedence in the area, the site shouìd be takcn as Seisniic Site Class D as definecl in iBC 2Aæ. We can assist with aclclitional soil ancl site parâmeters as needecl. lf othcr lbunclation types ârc considerecl. we sheruld be contaclecj lbre aclclitional analysis arrd design recomnrendations. .lob No. 107 0075 ^ r--tP.G€<Þtecn 5- FOLINDATION AND RETAINING WALLS Foundalion walls ancl retaining stmctures which are laterally sr-rpporterl ancl c¿ut be expected to undergo oniy a slight amount of deflection should be designed for a lateral earth pressure computed o¡t the basis of an equivalent fhiid unit weight of (r5 pcf f'or backfill consisting of the on-site clay soil and 45 pcf for backfìll consisting of irnported granuiar nraterials. Cantileverecl retaining strtictures which are separate liom the residence ancl can be expected to deflect sufficientì.v to mobjlize the full active earth pressure concìition should be designccl f'or a iateral carth pressure conìputeci on thc Lrasis of an equivalent f'luid unit weigirt ol55 pcf"lbr backfill consisting of tlre on-sire ciay soil ancl 40 pcf fol backfìll consisrirrg of-inrportecl grzrnular nl¿rterials. All foundation and retaining structules should be clesigned f'or apprcpriatc ìrydrostatic ancl surcharge pressures snch as adjacent footings. rralJjc. construction nraterials and equipment. 'l"he pressures leconlmenclecl above assllme chaineci condiiions behinr1 tire walls ancl a horizonlal backfìll surfäce. 'l'he builr1up o.lr,r,ater behincl a wall or an uprvzrrcl sloping backf¡ll surface will increasc the lateral pressure inrposecl on a f-ounclation wall or. retaining structure. ¡\n unclerclrain should be provitiecl to prevent hydrostatic pressure buildup behind rvails. Backfitl shoi¡id be placecl in uniÍ'oiin lifìs and con:pactecl to at least 90%ol' iLre maximunì standard Proctor clensity at near oplimum rnoisture content. Backfill ir: pavement areas should be compactecl to at leÍìst 95% t>f lile n:aximu¡n stanriarcl Proctorclensity. Care should be taken nol to overcompact the backlìllor Lrse largc cclr-ripnlen[ near rhe wall since this could cause excessive lateral pressure on the wall. Sonlc settlenlent of deep ibun,Jatio¡t wall back-fill should Lre e.vpecled e''.,en if'tl:e malerial isplacec! correctil,and could resuh in distress to facilities constructed on the backfill, We reco¡nrnend imported granul¿u'soiis f-or back wiil help ibundation walls ancl reraining str¡:ctures because their use results in lo'tver lateral earth pressures and they wiil he1¡l irnprove stibsurfàce drainage acljacent the builciing. Imporled granular ivall backfill should conlain iess than I 5% passing the Nr,i. 200 sieve ancl have a ¡laximunr size of l: ínches. Cra¡lularmaterialsshouldbeplacecl lowithin l'/zteetofthegroundsuriàceanc'l Jolr No. ljl {)015 C'd!:tecfr 6- to a mi¡limum of 4 feet beyond tl:e walls. 'I'he upper lYz t'eet of'the wall bacl<fill shoulçl be a relatively impelvious on-site soil or ¿ì pavement structuîe shoukl be proviclecl to prevent su¡fhce lvâter infilrration into rhe backfill. Spread footings rnay be used fbr support of retaining walls separate l}om tlie rçsitleiice or garage, provided some differentjal movement and distress can be loleratecl. Footings should be sizecl ftrr a maximurn allowabìe bearing presslri.e of-2^500 psf. The soils in the area typically possess a Jorv corrosivity potential ancl "I'3;pe 1/ll portlancl cepent is typically r-rsed in the area. l"ootings shouìd be provided r,vith aclequate soil cover above their bearing elevation lor frclst prolection, Placement of fbunclations ¿lt least 42 inches below extel^ior grade is recontmended for this area. l-lre lateral rcsistance of'reraining r.vall {'ootings wilì be a comlrinatiorl olthe slicling resistance ol'rhe looting on the fbr-¡nclatio¡l materials and patssive earth pressure against the slcle of'rhe 1-oori'g. Resisiance to sliding at lhe bottoms ol'tlle f'ootings can be calculatecl basecl on a coefTìcient ol' Ir'icti0n o1'0.35. Passive pressurc against the sicles of the fbotings can be calcr-rlated using an ec¡uivalent fluicl unit r,vcight ol'350 pcf fìrrthe on-site cla1, soil. 'l-he cocfjìcicnt ol' fiiction ancì ¡rassive pressure values recomnrendecl above asslune uitirnate soil strengrh, Suitabìe fäctors of safèty shor-rlcl Lre inclr"rded in the clesign to limit the strain rvhich will occurat the ultinlale strength^ particulzrrly in the case of-passivc resistance. Fill placecì against the sides olthe fbotings 1o resist lateral loacls shoulcl be compactcci to at least 95% of the nlaxintum standarcl Proctor clensity al near optin':urn nloislure conterlt. TI,OOR Si,ABS Floor slabs present a ilroblem where expânsive materi¿rls al'e present near Jloor slab elevation Lrecause sufflcienr clead lo¿¿tl cannot be imposed on rhe¡n to resist the uplifì pressure generated when the subgrade materials are wetted ancl sweil. We recc¡ntmend that structural floors with crawlspace below {or void form for reinforcecl concrele sja6s on piles) be usccl for all floors in buildings that rvill be sensitive to r.lpwarcl nrgver¡rent. Slab-on-gracle constructiott ntay be usecl provir.led the risk of clistress is nnclersiood by the owner. We recomlnerrd placìng al leasl 4 fèet of'granular sTn-ìctural fìil (s¡ch as roael base) below' floor slabs in ordcr to help recluce slab ¡rove¡le¡rt cllle to cxpansivc se;ils. lob No. l,07 00'75 cåStecn 7- To reduce the effects of some differential movement, non-stnìctural floor slabs shorild be separated fi'om all bearing walls, columns ancl partition walls with expansion joints which aliow urrestrained verticai move¡nent. lnterior non-bearing partitions resting on floor slabs should be provided with a slip joint at the bottom of the wall so thar, if the slaìr moves, the movement cannol be transmitted to the uppeï structure. This cletail is alscr important for wallboards, stairways and door frames. Slip joints tvhich allow at least 2 inches of vertical nlovement are recomrllendeci. Fioor slab corltroljoints shor:lcl be usecl to reduce ciamage cir-re to sirrinkage crackr-ng. Joint spacing and slab reinfbrcenlenl shoulcl be established by the clesigner basecl orr experience ancl the intencJecl slaLr Lrsc. A ¡ninimum 4-inch layerof relalively lree draining gravel shoulcl bq piaced imrnedialely beneath basement level siabs-on-grade for drainage. 'l'his lnaterial shor¡lcl consist of minus 2 inch aggregate with less than 50% passing tire No. 4 sieve and iess thanZVo passing the No. 200 sieve. Required fiil beneath slabs shor-rlclconsist of-a suitable imported rìon-exp¿ìrìsive glanr-rlar material, excluding topsoil and oversizeci rocks. l'he suitability of structu¡al fill materials shoulcJ be evaluatecl by thc geotechnical engineer pr.ior to placernent. l-he 1ìll shoulcl be spread in thin horizontal lifts. adjusted 1o at or above optirnunr ntoistule content, arìd compacfed to 959¡ olthe maxiniunr slanclarci Procto¡ density^ r\ll vcgetation, topsoil ancl loose or disturbed soil shoulcl be rentoveci prior to fìlì placemenr. 'I'lte above rccclmme¡ld¿rtions r.vill r:ot prevent slab hcave if the e,vparrsive s<lils unclerlying clay subgrade soils become wet. l'lowever, the reco¡ilnie¡idaiions iviil ¡'rdiice tlie effects if slab heave occurs. All plurnbing lines should Lre pressure tested belore backfìlling to help reduce the potential for wetting. LTNÐËRDRAIN SYSTEM Although grounclr.vater was not erlcounterecl durjng our ex¡rloration. it has been our experience in mountainous areas and where clay soils are present, lhat local perched grounclwater may develop cluring times of heavy plecipirâtion or seâsoíìal runofl'" Irrozen Job Nt¡. 107 0075 cåBtecn I, ground during spring runolÏcan cr{iåte a perched conclition. fherefore, we recomi:lencl below-grade conslruction, snch as crawlspace and basement areâs, be protectecl fiom lvetting by an uncierclr¿rin systenr. 'l'he drain shoulcl also act to prevent builclup of hydrostatic pressures behincl founclation walls. J'he underdrain system should consist of a drainpipe surrounded by free-draining granular material placed at the bottom of the rvall backfill. T'he drain lines should be placecì at each level of excavation and at least i foot below lorvest acljacent frnish grade. ancl sìopecl at a nrini¡¡um,lon grade to a suitabie graviiy outlct. Free-ciraining granuiar-nlateriaÌ used in the drain system should consist of'n¡inr-rs 2 inch aggregale with less than 50% passing the No. 4 sieve ancl less than 2a/o passing the No. 200 sieve . The drain gravel should be ar least 2 fbet cleep. Void form below the gracle bearns anri slabs can act as a concluit f'or wâter flow. An irnpervior,rs membrane such as a 30 nril PVC liner sir<¡uld be placed below the clrain gravel in a trough shape ancj attachecl to the gracle bearn or lounclation wall with inastic to keep drain water fì'om flowing beneath the grade bcarn anci to other areas of the building. We should revier,v the lounclation ¡;lan l'orsubsu¡fhcc clrainage locations. SITE GRADING Fill ¡raterial useti inside bLrilcling limits (such as below sìabs) ¿¡n.i w'irhiii 3 feet of pavernent grade should consist o1'a granular material sucit as road base. Fill shouid be placecì ancl compactecl to ât least 95o/o of the maxi¡lum st¿ìncl¿x'ci Proctor clensity near the optimunl moisture content. Fill should not contain organic rnatter or other deleterious substances. The geotechnical engineer shoulcl evalu¿rte the suitability of proposecl fìll nraterìal-* nrior to nlacement. In fill aleas- the natr:ral -soil-c sþ9u¡cl be scarifieclto a denth*¡ _sù, rui.¡ ¡i ¡.vu r.v, G i¡u.p,ij¡ of 6 inches, adjusted to near optirnum nroisture content and compacted tcl provicie a unifonn base for fill placement. The clay soil encountered cluring this stucly will be expansive wiren ¡rlaceci in a compactecl condition. Consequently, this soil shoulcl not be used ¿rs fill ¡naterial beneath builcling areâs or directly benealh paverrìent areas. -l'he clay soil can be used fbr fill nlaterial near the bottonl of fills outside builciing areas. Job No. l07 0075 cåBtecn -9- A detailed slope stability evaluation and resultant recomrlendations are beyond the scope of this report. However, general guidelines are presented below so planning ancl design of the structures can be accomplished by the project ciesigners and contractor. After initial pianning ancl design are completed, we should be contacted to review the proposecl grading plan and conduct additional analysis as necclecl. f ) Pe¡lnalleni u¡uetained crli ûr Íiìì siopes shorilt-i bc gracictì at 2 hurizoritaì io I vertical. or flatter. 'l'emporary cr-lt slopes should not exceecl I horizontal to I vertical. l-he risk of siope instability',vill be increasecl if seepage is encoLìnterecl in cuts. 2) Fills shoLlld be limited to l0 feet in height provicled that they are properly compacted and clrained. l"he gror:nd sulfàce Lrnclerlying all fill shoulcl be prepared by removitrg ali organic nratter, scarif ying to a depth of 6 inches and compacting to 950/o o{ tbe maxirnum standard Proctor density prior to fill placernenl. Fills should be benched iìlto site exceeding 20{'/o s1ope. 3) Positive surfhce drainage should be plovided around all permanent cuts and fills and steep natural slopes to clirect surf'acc'runofTaway fiom tlre slope l'aces. Slilpes ancl otirer stripped areas shoulcl be protectecl ergainst erosion by re-vegetation or other methocls. 4) Site gracling, drain deiaiis and bujlding plans shouìcl be prepared by qualìfiecl engineers lirniiiar with the sulrsurfbce contjitions in the area. The constructio¡l sequence plan of'excavating. wall construction and bracing ¿lnd backfilling shoulc! be prepared by the contractor. SUF.FACE I]RAiNAGE lhe following drainage precautions should be observed during construction and maintained at all times alier the buildings have been cornpletecl: l) Excessive wetting or drying of-the firurnciation excavations ancl underslab areas should be avoided during constr'r"rc1ion. Drying could increase the expansion pCItentiâl ol'the soiìs. Job N<r. l9l 0075 HPGecbtech - r0- 2)Exterior l¡ackfill shouid be adjusted to near optintum troisture ancl compacted to at least 95Yo of the maximum sTanclarcl Proctor density in pavement areas and to at least 90% of the maxirnuin standard Proctor density in landscape areas. Free-draining wall backfìll should be cappecl with about lYzfeet of the on-site clay soil to reduce surfäce w¿ìter infìltration. The grouncl surface surrauncling the exterior of the buiìc'lings shoulcl be slopeci to drain ar,val' fì'om the fcrr"¡ndation in alJ directions, We reconrrnend a minirnum slope ol l2 inches in the {ìrst I 0 fèet in unpaved areas ancl a minirnttnl slope o1'3 inchcs in the f lrst l0 Jeel irr pavecl areÍìs. Roof clownspolìls ancJ clrain:; should dischargc r,vcll bcyoncl thc limits c¡f ali backfill. Sprinkler heacls and landscaping which requires regular heavv irligation. such as socl, should be located at least 5 f'eet fi'ont fbundation walls. ?\ 4) s) LIMITATIONS 1'his study has been conducted in accordance with gorerally acce¡rted geotechnical engincering principles and practices in this area ¿ì1 this tirle. We nrake no w¿ìrr¿lnty eirher express or impliecl. "fhe conclusions and recornrnenclations submitted in this report are based upon the data obtainecl fio¡n the exploratory borings d¡ilìed at the locations indicated on Figure i , the proposecl type of construction and our experience in the ¿lrea. Our services do not include deter¡nining the presence, prevention or possibility of ntolci or other biological contaminanis (MOBC) developing i¡r the fi-rture. If the client is concerlred about MOlltl, dlen aprofès.sional in this special field ol'practice should be consulfed. Our iìndings include interpolation and extrapolation of'the subsurfàce conditions identifìed at the exploratory borings anci variations in the subsurlace conditions may not become eviclent until excavation is perforrned. If conclitions encountered cluring construction appear to be difl-erent from those desclibed in this repcrt, u,e should be notifìed at once so re-evaluation of the recornmenclâtions may be made. Job No. 107 007-5 cåBtecrt -il- This report has been prepared for the exclusive use by our client for design purposes. We are not responsible for technical interpretations by others of our informatio¡r. As the project evolves, we should provide continued consultation and field services during construction to review and monitor the implementation of our recommendations, and to verify that the recommendations have been appropriately interpreted. Significânt clesign changes may require additional analysis or modifications of the recommendations presented herein. We recommend on-site observation of excavations and lbundation bearing stmta and testing of structulal fill by a representative of the geotechnicai engineer. Sincerely, I-IEPWORTH - PAWLAK GEOTECT{NIT]AI,, INC. Trevor L. Iúrell, P.Ë Reviewecl by: Steven L. Pawlak, P,E. TLK/vad Lake/Flato Architecis -.Attn: Kristin Wiese Datum Engineers, Inc. - Attn: Thomas W. Tayìor CC Job No. 107 0075 G'eötech u)Z \ m LOT 2 SCALÉ: 1"=100' =\*\- 1 07 0075 GEOfiCHNICAL LOCATION OF ËXPLORATORY BORINGS FIGURË 1 BORING 1 RESIDENCE ELEV.=7315' BORING 2 RESIDENCE ELEV.=7325' BORING 3 RESIDENCE ËLEV.=7325' IJUñll\tf, + RESIDENCE ELEV.:7311' BORING 5 GARAGË ELEV.-7332' 0 û FF 18112 WC= 12.6 DD:101 32/i2 ¡ryç:13 5 FF DD=115 14/12 ðÐt t¿32/12 WC:15.5 DD=i11 5 E.29112 e 42/12 wc-15.6 DD=99 -200*88 1Bl12 s/C=191 DD=9ô 11112 WC:13.9 DD=1 12 29112 10 1et12 10 WC-15.0 DD= 109 35/12 24/12 WC=22,2 DD*103 -200:96 LL*52 Pl:35 25112 27112 15 20t12 15 þ UJ t¿Jlr- IïþILul Õ þ I.U IU * Tt-L IIJÕ 40112 23/12 WC=1ô.s DD= 110 -20û=86 24/12 20 16t12- 2A t^11,?^112 21112 3Q112 WC:22.6 DD=104 LL=5/ Pl:37 25 25 2,1/12 40/12 30 13t12. 30 BOTTOM OF- BOËING AT 43 FËET Note: Explanatian af symbols is sho¿un on Figure 3. 35 35 FIGURE 2LOGS OF EXPLORATORY BORINGS HEPWOR'f H,PAWI.AK 1A7 tO75 LEGEND TOPSOIL; sandy clay, organic, upper few inches frozen to soft and moíst with depth, dark brown CLAY (CL); slightly sandy to sandy, with scattered sancly gravel lenses with depth, stiff to hard, moist, brown, calcareous in upper 15 to 20 feet, slightly porous, medium to high plasticity. Relatively undisturbed drive sample; 2-inch l.D. California liner sample. Drive sample; slandard penetration test (SPI), 1 $-inctr l.D. split spoon sampie, ASTM D-i586. Drive sample blow count; indicates that 32 blows of 140 pound hammer falling 30 inches v,rere required to drive the California or SPT sampler i 2 inches. Practical drilling refusal NOTES: 1. Expioratory borings were drilled on February 15,2A07 with 4-inch diameter continuous flight power auger 2. Locations of exploratory borings were provided by the client and measured approximately in the field by tapirrg from features shown on the site plan provided. 3. Ëlevations of exploratory borings were obtained by interpolation between contours shown on tl¡e site plan provided. 4. ïhe exploratory boring locations and elevations slrould be considered accurate only to ihe degree implied by the method used. 5. The lines between materials shown on the exploratory boring logs representthe approximate boundaries between material types and transitions may be gradual. 6. No free water was encountered in the borings at lhe time of drilling. Fluciuation in water level may occur with tirne. 7. Laboratory Testing Results: WC : Water Content (o/") DD : Dry Density ( pcf ) -200 : Percent passing No. 200 sieve LL : Liquid Limit (% ) Pl : PlasticiV fndex (% ) æ H n F LI I 19t\2 107 0075 LEGEND AND NOTES FIGURE 3 c4)c){)o-a_Q Lr¡$rdl' !U r¡il c)<-ç>L ñ ıoã--Filı's åi s^- (!) o tTYcn'rñ# I Þ;Õ>:o>ıöù{cQ-oË o':*=ärlIIIIc)O()rqfc)aOrO(JÕU)l<t¿lc3U)CNtrjco-Õt¡i:o_ô-çrUJcc3CÍ)ü)t!ELtlu:o-o-(\¡r(3ñlFq-U=ogo(JkaaH',Lc)co{f)Èt/)o) co-O)*";*- c.)l' c)\u r,ll () O')P>-(l (uo)€.,=(\cil_r!U) U]ı.È* F-.1¡roÃgçoıdötrcô >h o>ðöüI/rì.--l_-1cOnx *o)*- ìtu(.,( "2. ) ruolstrtvdx=l - Notss:tudy\¡o3C!( ø ) Nolsnvdxr - Notssfudt/ìloorf,l"-O()¡-(3rØT3U)UJgt*cntrlþzotrâJotf)z()IJJu3U)rftr¡tr:(5r coMPRE{iStoN - EXPANSTON ( % )ÕC0MPRESSION - EXPANSTON { % )è,¡l\)&Jê(¡C,)OJ()l\)c)JJt){OOT-trmü-gflrnØU)c3TXu)T}rmclTflrnØØc:ÐmxtttfiØC]<oHAo=€ çgrygä ã.; ;€ I*oYrrtolo-q*\< =ì* ,(D(Jì8lc)f)ooof,m€ -*:Y. ı q)(O-ı'ãlIII-1-fr(rcl<ciPi2o=åÈF53 ä ãã ;€ gHå,, 4<to6 llð'9.(D!oooEoI,/Tf-€-ãsè ıf=úrJ(o-ı=Jc)\¡d)O{(JlU)ãmrrnozØorU{Oz{m(t)-{:umç>Cr{v)'T1ocTm(n OoMPRE$SION - EXPANS|OÍ! ( ?; )N)CoMPRESS¡ON - ÊXPANS|ON ( % )t\)"JC)N)c,)oN}pJbo<)pJboC)Ol,Tr:mÇ'0ÐmU)a)Cmg,-UTrrnclït:Bmg){t)c:Dmx-{tä $5 ã.lJ_ri-!.Yã8: ä ã=. ¡.:'^.a Pî Yfn="4;d EÉ\<-êJ ^O (J ll.-0)d' <gJJc) (¡(ot)Ðoo'ìcc)I/IIIm<êñqà ı:1=c4=flØ(]<cj ga o--¿J_{DÍÐ vf_:(DLHX; ıJ-*-'^:i " {¿ r/.^ (^ - UX,' il :lanY'¡+;d_ g*Nc) Ir3E*€.* C)NJ!A*Ln;;bã:)(D-nı-*vv=c)(D(9)(/) +I/!TI-¿)<< -7=-U +cÕ-efJO-.¡c)!ûlU)€mrrIozØorÐ{oz-lmcn-l:ÐmU}cTçnT6)C3mct) HEPWORTH-PAWLAK GEOTECHNICAL, INC.TABLE 1SUMMARV OF LABORATCIRY TEST RESULTSJob No.107 0075SAMCATIONNATURALMoiSTURECONTENTNATI.JRALDRYDENSITYGTIONPERCENTPASSINGNO.200SIEVETTERBERGTSUNCONFINEDCOMPRESSIVESTRENGTHBORINGNO.DEPTHGRAVEL(%)SAND(%)LIQUIDLIMITPLASTICINDEXsotLTYPEi413.5H5Sandy clayI15.69988Slightly sandy clay2I19.196vStst0net422.2103965235Slightly sandy clay913 "9112r9Sandy clay16.511086Sandy claySandy claySandy ciayaySItstonentsSandy clay37itl1C)41011Crg15.522.6I 1,.Õi 5.011/1L+r0T5