5300 GLENWOOD AVE 2018-01-02 MF Import

� Glemvood Tcrracc Filc Numbcr 126994 May !Z, 1994 Page IS 71�e fill surf'acc should be expcctcd to setlle ovcr timc. The design oC the surfacing in front of ihe building should talce into account the potential difl'erential settlement of this surface. These setdemcnts will largely be apparent in non-pile supported slabs and sidetitialks. Wc recommend Uiut "transition" slabs be used bctwecn pile and non•pile supportcd slabs(such ns sidewalks),to prevent vertical oETsets due to differential senlement. The Iransition slab is a reinforced structural slab thnt is doweled into the pila supported structure nnd the non-pile supported slab. As settlemcnt occurr, the dowels act as hinges allowing movement withoul vertical offsets at the slab joints. There is some risk involved with the use of auger cast-in-place piles,due to the presence of rubble or other obstructions that underlies the site wilhin the old fill. We expect, while using an auger type drill, refusal may occur in the older fill. Pilcs tertninatcd on rubblc or with shallow rcfusal dcpths will need to bc rc- drillcd. We recommend that design criteria for re-drilling should be providcd with the job plans and specifiqtions,such that the contractor may know how to spnce redrillcd holes nround lhc abandoned pile, if nceded. All abandoned piles (groutcd but not end bearing) in the fill should not bc connected with the grnde beatn system. �Ve have calculatcd pile bearing capacitics based on penelmtion into the ouRvuh and laterel pressures witl� an estimatcd detlection. We have providcd these values in Table 1 bclow, showing t}Pical pilc diamMers. 'I'hcsc valucs use soil/pile interaction only; lhe capacity oC the pile may be controlled by lhe structural design. A vcry import3nt design par.tmeter is the potcntial for do«�ndrag on Utc piles. Downdrag would be caused by the fill settling around Uie pile and trying to puU U�e pilc down��ith it. The downdmg forces are dep�:ndcnt on the dcpth of the fill. 'Il�e pile structural design oPtlic pile should account for tliae do�mdrag forces. That is, the allowablc design of die pile should be enough to take the total load shown in the pile capacity column. TFie valucs shown in Table 1, wcre calculatcd using an embeddment depths of 3 and 7 feet into the underlying glacial soils. Higlur design capacities can bc achieved using larger diamMer pilcs and more pcnctration. lf higher valucs arc ncafed, we can provide them based on actual anticipated pile loading. NE.LSON-COUVRETTE&ASSOCIATES, INC. FEB-23-1996 12� 1l1 206 481 2510 ?6: P.17