1505 INDUSTRY ST Geotech Report 2018-01-02 MF Import

disturbed and softencd. In addition, a signifi.ant cmount ol'mud �an be produced. Therefore, to protect [he subgradc suils and to providc an adcyuate working surface tor the contractor's cyuipment and labor, �ce recommend that a wurking pad layer be placed over the exposed snbbrade soils. The .vorking p�d laycr should be about l2 inchcs thick and should consist oF' I'/:-inch minus cican crushed gravel witit negligible s,md or silt. The working pnd laycr can be placed in one lift and should be compaetad to at le:�st 95 percen[ of thc MDD (per AS'P1f D 1557). If.t working pad laycr is uscd, and if rclatively dean immcdiatcly prior to construction of thc slab-on-gr�dc, it may bc uscd to rcplacc d�e Ginch capillary brcak I;rycc I lowcvcr, if ihc warking psd bcromcs cantaminatcd with suil,thc contamina:ed arcas shouid � bc ovcmxcavatci tu a dcpth ol'G inchcs tiir pl:�cc:mcnt o(thc capillary brcak gravcl prior to cunsuvating slabs-on-grade. Structural Fil! All �ill, whether existing ou-site glacial tilf soil or imported soi', that will suppurt �loor sl:�bs, pavemen[ nreas or f'uundations, ur be placed against retaining walls or in uulity trcnchcs should ecnerally meet the crilcria for sinictaial lill prosentcd bclow. "Thc suitability uf:;uil for asc as shlictural fill dcpcnds on its gradation and moisture contcnt. Jl:�terials. hiatcrials u,cd lo constnict building pads, cmbaukmcnts and surthcc parking areas arc classi�icd as structural filf tor the purposc of this rcport. Stnicu�ral till material quality varics depeading upun ii, use, as described bclow: I, tiuuctural �ill placed to cons'tn�ct embankmcnt and parking areas, to bachtill u[ility trcuchcs and to ,upport building and tloor slabs may consist of on-sitc glnci�l soils nrovidcd that thc soils arc cundiliuned for thc requircd compaction. On-sitc till soils will bc suitablc for usc ns structural lill during dry wcathcr wnditions in arcas nccding 95 perccnt compaction. If structural fill is pLiced during wct wcaihcr, thc stnictural lill should consis[ of impurtal gravcl borrow as dr.:cribcd in Scction z)-03.1-1(1) nf dic 2004 Nashington Statc Departmcnt of Transportation (NSDO'I') Stnnd:ad Spccilications, with the addition;il restric[ian that the �ncs content be limited tu no morc th;m 5 pera:nL IF nccdcd, building foundations should also bc sup�orted un importcd �:ravcl borrow. It is possiblc io usc on-sitc till soils during wcl wr.tthcr fur arcas rcqt�inng only 90 pereent compaction provided the cartl�work cunirnctor implements good wct wcatlicr tcchniques. 2. Structunl till placcd immcdiatcly outsidc bclow-gradc walls (2-foot-widc drniimgc zonc) shonld eon�ist of washcd 3/S inch [o No. S pca gmvcl or coniunn to Scrtion 9-03.12(4) of thc 2004 �VSDOT Stnndard Spccifir.11icns. � 3. Stnictural lill placed as r,�ushed siirfacing base course bclow pavemen�s sliould cunfi�rn� tu Scction 9-03.9(3)of tlic 2004 NSDOT Standard Spccifications'. J. Sirucwral lill placed as capillary break below slabs should consist of I!G-inch minus cican crushcd gravcl wilh ncgligiblc sand or silt in confomiancc witii Sectiot��-03.1(4)C, grading No. i i o(the 2004 \VSDOT Stand:ud Spccifien�ions. Rcusc ol' On-si[c N:�tivc Soils. 'Che till suils contain a IJgh perccntagc of fincs and �vill be sensitive to � ch:ingcs in moisturc cantcnt;md dil'licult te hmidlc mid compact during wet wcathcr. IThc densc tu very dense clacial till and outwash deposits are expected to be suitable for stn�ctural fill in nrcas rcquirin� cnmp:xtion �o ,u Icust 9� percent ol'�IDD (per ASTVl D 15�7), provided �he work is ;iccumpli;hcd during thc nnrm;dly J�}' sc.isun (Junc throuyh ScptcmUcr) anJ that !hc soil can be properly Fl;, .�,� :_ql'i.rirq.r;�:� �� l�iri�' � GEOENGINELp� L�audrr'P.:Cq9