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tsr��d«n, <br />Patixive Pressurc Mc�hnd: The pnssivc pressurc nppronch is conscrvntivc by ncglcc�ing Ihc rcdistribulinn <br />of verlical stresses and sliear li�rces Ihat dc��clup nc:u' Ilic boltom of Ihe pier :md contributc lo resislir�g <br />la�cral londs. \Vc reconuncnd using Ihc allo�vahlc p�ssivc carih pressure (expressed as equivalcul �uid <br />unit �veighls) lisled in "I';ibic 3. '1'lic allo�vablc passi��c pressure I'or soils Uelo�v Ihe maxinmm deplh of lhc <br />tcst boring nny hu assumed tn he as that sho�vn for �hc lotvest depih incrcmcnl bclo�v. <br />r-ao <br />30-37.5 <br />'1'nblc 3 <br />Allo�rablc P:issive I'ressu� es <br />Allowablc 1'assivc Pressinc (pcQ <br />0 <br />3uo <br />iao <br />200 <br />Thc allo�vable passi��c carth pressurc prescnlcd in Table 3 m,iy bc assumed to be ucting �ver mi nrca <br />mcnsuring 2 picr diameters in ���idth hy R picr diamelers in dr.ptl�, neglecting Ihe uppermosl 2 fecl of <br />cmbcclmcnt hclo�v the ground surfacc. Accuiding lo Ihe NAVI�AC Dcsign ivlamril i.02 (19R6), a I;ita.d <br />dcllectiun eyual Io about 0.01 �imes �lie ��ar Iengtl� woulcl bc required lo mobilize the allomab!e passive <br />pressure presenled abo��e. Highcr dellect�ons ���oulcl mobilizc higlter passive pressures. \Vhen developind <br />Ihc allo���nblc passivc pressurc lisicd in Tnhlc 3, wc havc incrnpnratcd a safcry f�ctnr of al least 1.5, which <br />is commonly applicd to transicnt or scismic loadins cnnditions. <br />Modulus ol' Suberade Rcactirni t�4cthod: Usin� this melhod, Ihc pier is designed to resist L•IlL'I'ilI IUIlfIti <br />bascd un acceptable laleril dcllcctioa liutiis. For sandy soils, Ihc cocflicicnt of horir.ontal suhgrade <br />rr,iction (kh) is con�idered �o be dircclly prupurliuu:d to llic dcpth .ilong Ihc pier. l'he fonnula lo <br />Jetennine kh is kh= ni,x, �vhere x is �hc dcplh bclom Ihc graund sin•f:�ce in inches. 1\�c reconunend using <br />the valuc for Ihe constnnl of Itoritonl;d subgr;idc rc�iclion (nn) for the various soil q�pcs prescnicd in'Cnblc <br />4 belot��. <br />7':iblc 4 -- __ <br />Cmisnuil nf Hnrizuntal Subgradc Rcaclion (n�) <br />Deplh ('feeQ nn (�rei) <br />O'L 0 <br />2-fi 5 <br />(-30 3 <br />30-37.5 25 <br />Consuvction Considcralions: Ow' crpluration rcecalcd �hc site soils to typically cousis� of ��ciy luosc <br />sauu'a�ed sands along n�ilh ��eiy soll silts o��crl;iping mcdium densc sands. 13ccnusc of Ihc ��c�y sofl <br />stn lici�l sile suils, Ihc tound,ition-drilling cantractor shnuld bc �xcparcd lu cnse ;:�c excavation lo prcvcnl <br />\'rriion \Yiidc•: .4ugus14.20J3 <br />rldnpt Ihoi�ci T'a. \CA07.9i72 Po�c 8 � <br />y� <br />