3003 W CASINO RD BLDG 40-56 2018-01-02 MF Import

n ercd within the fill or within renular ockets in the lacinl tili. The weter ( weter mey be encou t B P 8 mey contribute to local sloughing of the wall of the caisson hole, but is not expected to require _ significnnt dewetering eCforts We have mnde observetions during the field investigntion progrem regerding the tendency for caving of open borehoies. 7'hese observetions were mede to eveluate the viability of caisson installation. Some ceving has been noted,end would seem to indicate thet temporary casing used to facilitete construction of the ceissons should be promptly installed during drilling. The cesing may be removed es concrete is pleced. We rccommend thet caissan bottoms be inspected by a representetive from Dames & Moore I _ prior to plecement of concrete in order to verify the suitabiliry of the bearing soil end bottom i conditions. 1 FLOOR SLAB We rocommend thet the Cloor slab be constructed on grade in the existing fill soil. However, the heavy floor loads throughout a significant portion of the floor area will require that strict -" preperetion measures be teken during construction to ensure satisfecrory perfurmance of the sleb during it+service life. The existing fill soil should be overexcevated by et least IS inches end recompected to 95 percent maximum dry density as measured using ASTM-1557 methods. Soft -' soils should be should be replaced with on-site or imported grenular soils. Prior to placement of - any compected fill, the exDosed subgrade should be thoroughly proofrolled, end soft zones ;,) further overexcevated and repiaced with grenular soils. � We estimete that total settlements of uniformly loaded ereas of the sleb mey be on the order ��; of 3/8 inch. Differential settlements of 3/8 inch may accur over distences of approaimetely SO feet where transitions from light to heavy loads occur. PEDESTRiAN TUNNEL Foundation Suonort — We recommend thnt the tunnel be designed es e rigid member end that the base of the tunnel be constructed on grede in the existing fill soil or in the glaciel till. The tunnel will then ect as a met founda[ion. The elloweble bearing cepacity of the fill soil if properly prepared should be I -- taken es 2500 psf. Proper preparation of the subgrede soil includes overexcavation below the floor level by at iesst I foot and replecement with select, free-draining granuler soil compacted to 9596 of the meximum dry density es measured by ASTM D-1557. Prior to the placement of any compacted fill, the exposed subgrade shoutd be thoroughiy proof-rolled, and nny soft zcnes excavated end repleced. 6 Dames 8 Moore