1135 CRAFTSMAN WAY 2018-01-02 MF Import

� Prclimina�y I�indings from Rc��iew of Gcotechnical Rcports North Marina Dc�clopmcnt ICvcrct�, �Vashington March 24, 2004 CG Projcct No. 157G � Pagc 4 • Thc loosc s;md zoncs arc c�pectcd to liqucf:v during a sienificant scismic evcnt. In Qie centrnl portion of � thc site, this will be rc(lected in aerial settlement, probably of at Ieasi several inches. Differential setNcment will bc on the ordcr of scvcral inches. Near �he outcr edges of the sitc, lateral sp-cading could � occur. "l�his would not bc cxpccicd to significantly impact the condominium structures, but could impact thc commcrcial buildings cxpccted to be on the northem sidc of the sitc. We have not completcd a � liquefactian analysis for thc sitc. 1Ve have bcen informed Uy thc Port that dcsigning thcir portion of the projcct to resist thc dcsign seismic evcnt was too cosdy and thc risk of latcral sprcndinc and movcment of � the bulkhcad walls following a seismic cvcnt would be acceptcd. � Anticipated dcsign considcrations for thc abovc itcros are as follows: • Pill to bc placed on thc sitc should bc schcdulcd such that it is in placc scccral months bcfore construction 1 ofsettlement scnsiti�e structures ur utilitics. '1'his ��ould allow consolidation oCsubsurface soils duc to thc � �vcight of thc fill. ' • Using stand�rd dasign, Ihc stnictures will necd to be suppurted on pilcs. 7'he piles �tiould minimire diffcrcntial sctdcmcnt and also prcvent setdement duc to liqucfaction. Since the espceted depths of thc Ipilcs arc on thc ordcr of 100 fcet, �vc anticipatc that steel pipc piles will bc required. �Ve estimate that the capacity of Qie piles would be 100 to 150 kips or even highec These piles �vould not be expected to resist � significant latcral movement during a seismic cvenL \1'e ��crc quoted a rough price of S25 per foot of instaUed driven pipc pile by a local cuntractor. Ilo��c�'er, «c note that stccl prices h��•c rcccndy incre�scd, � this would incrcasc matcrial cost,. • M altcrnativc ro thc dccp pilrs is tu usc stonc cohmms. Thcsc arc �•ibrated into placc, probably on thc � order of 40 fcct deep. The colwnns provide stnuwre support to reduce sctUcment, and also improve thc ground conditions to rcducc liqucfaction potcntial. If this approach is taken dic columns �vould bc � required throughout building footprints. 1Ve were provided a rou�h cost estimate of S 10 ro S 12 per squarc foot of trcated ground ro install thc stone columns by a ground improvement contractor. If it ��as desired to rc�ist liqucfaction, thc srone column vestment «•ould estcnd outside of Ihe building footprint. i fhc aho�e di;cussiun is intrndcd to pruvidc gcncral dircction of gcotcchnical aspccts ofthc projcct and possiblc � solutions. We have only complcted a literature research to date. A more in depth subsurface exploration and analysis program is rcquircd to evaluate the site to provide specific design details. Wc havc provided you with a � S i Cornerstone Geolechnical, Inc. /�1