1315 PACIFIC AVE 2018-01-01 MF Import

DnJnaye Drainage behind the permanent beloH� grade walls is typically provided using s[rips o(drainage material attachcd to the lagging betw�een the soldier piles. The drainage material strips should he wnnected to weep pipes which exicnd through the perimcter building wall at thc footing elevation. The wecp pipes should be hydraulically connected to the sump, and may be designed for a hard connection to the perimeter footing drains discussed above in"Below Slab Drainage." Thc catth pressures presented in Figurc 4 assume thal adequate drainage is provided behind the wall. As discussed prcviously, prcfabricated geocomposite drainage strips, such as MiraDrain'*', should t�e installed vMically betn•ecn the soldier pilcs. The drainage strips should be installed on the excavation side o(the lagging with Ihe fabric adjacent m thc lagging. The drainagc strips are typically a minimum oC 16 inches wide and extcnd the cntirc hcight of the walL Additional drainagc strips may be necessary in wet arcas. EARTHWORK Subprade Preparation The in-sim soils at thc planned parking Icvel finished tloor and faoting clevations may consist oCdense to vcry densc sand with variaUlc silt conlcnt ovcr thc majority of thc site, except whcre deep fill associated with the sewcr pipe exists. Gxisting fill may also cxtend b.:low thc parking slab in local areas. The cxposed subgradc should bc cvalualcd aflcr sitc cxca��ation is completc as dacribed in the slab-on-gradc subgradc prcparation scetion of this rcport. Sbuctural Fl11 Fill placed io support foundations, thc parking slah•on-gradc, placcd brhind rctaining sttuctures, and placed below sidewalks H�ill necd lo bc spccificd as swcwral fill as dcscribed below: • Structural fill placcd lo support building foundations designcd for no more than 4,000 psf bearing pressure should consist of imporled Gravel Dorrow per WSDOT Standard Specification Scction 9-03.14(1). • Structural fill placcd to support thc parking levcl concrctc slab•omgradc should consist of importcd gravcl if placed during wcl weather; however, if work is performcd during the drier summcr months then impoAcd common borrow per WSDUT scction 9-03.14(2) or suitablc on- sitc soil may bc used. • Structural fill placcd around perimetcr footing drains and undenlab drains should meet the requirements oC 1A�SDOT Spccification 9-03.12(4), Gravel Dackfill tor Drains or consist o(pca gravcl. • Swctural fill placcd as capillary brcak material below the parking Ievcl slab-on-grade should mcc�thc rcquircmcnls of WSDOT Spccification 9-03.1(4�,Grading No. 57. • Strucwral fill placcd as crushcd surfacing basc coursc bclow pavcmcnts and sidcwalks should mcet Ihe rcquirements of N'SDOT Specification 9-039(3),Crushed Surfacing Base Course. On-sitc Soils. 7hc on-sitc soils arc moisture scnsitivc, finc-greincd soils that will bccome wsily dis�urbcd w�hen wct. 13ased on our laboratory tcsting, the majority of thc cxcavated soils will likely havc in-sihi moisture con�ents ncar or abovc the optimum requircd for compaction. Suitable on-sile soils may be used during the drier summer months as structural fill bclow the parking level slab to backfill F71r.\b. I71C-001-INI raR�'/3 �7[OEMO�MEE�� Junr M1.1011,1' I�