Laserfiche WebLink
� <br />SHAidi�lOi� F:VJILSON.INC. <br />eround acceleration that may be expeiienced at the site. These pressures assume drained <br />� conditions :md a horizontal ground surface. <br />� It may bc Ibund that thc incrc:isc in latcral cmlh pressures during carthquakc loading can be <br />accommodated by the 33-percent capacity incre:�se that is allowed in thc strength of swctural <br />mcmbcrs by thc UBC. Thcrcforc, walls that arc adcqualely dcsigncd for static loads may bc <br />� capablc of withstanding thc combincd cffccts of static and carthquakc loading during thc desien <br />earthquaka Thc strucwral cngincer should considcr whether or not the seismic earthquake <br />t increment is necessary or if ihe strength of the strucwral members accounts for the increase. <br />7 <br />� <br />� <br />� <br />Notcs: pc(= poimds per cubic (unt <br />li = �eaU hcight in fcct <br />� Thc cquivcdcnt (luid unit ���cights givcn abo� c.irc bascd on thc assumptions that thc ground <br />surfacc bchinJ thc ���ail is Icvcl and thcu proper dr:�inagc is installcd to prc��ent watcr from <br />building up bchind thc wull. Por walls �vith a sloping backfill, add l pcf to thc cquivalent unit <br />� ��cights gi��cn abovc for cach upward degrcc of backfill inclination. <br />10.G Lateral Kcsislance for Ycrmanent 1\'alls <br />Por structures founded on footings, lateral loads may bc resisted by a comoination of basc <br />friction and passivc pressure against thc footings and buricd portions of building �aalls. �Vc <br />recommend that the Uase sliding resistance bc dctcmiined Uased on an allowable coefGcient of <br />fiiction of O.dS and 0.35 for advancc out��•ash/glaciai till and glaciolacustrine matcrials, <br />respcctivcl}'. \Vc rcr.ommcnd an allo���aUlc passivc pressurc of 360 pcf and 260 pcf for nativc <br />soil and compacted st�uctural fill, respecti�•ely. These passive pressures are for soil above the <br />,�roun�l��;�tcr t;ihlc. I�or natic� soil und com��:ictcd structur:il fill bclo�v thc ��round��atcr ��•c <br />I.I.U'y��1.1\15 f.lnyrll,l <br />� 1 <br />2 I -1-09G�1-1-00� <br />