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i <br /> �, <br /> � r)nce thc tici,ack; urc in�uillcd. Ihc pulluui c;ipacit}� u(ruch ticb;ick i; tr,tcd ;md thr ticback i� lucl.��6uf�f <br /> to the suldier pilc at or near ihc de�i tn tieback loud. "I�icbucl:; ty�ic:ilh cun�ist of stecl ;tr:md, or bar, <br /> that are installcd into pre-drilled holcs and then cither tremie or pressure erouted. "limber la�_gim, is <br /> i typically installed b�hind the ilanees of the stccl beams to retain the suil loc,rted bet�cecn the soldier pilrs. <br /> Geotechnic�l desi�sn recommendations for e;ich of these eomponents of the soldier pile �nd tiebuck �c:ill <br /> s��stcm arc presented in thc follo���ing sections. <br /> I tiuldier Piles. Nc recommend that soldier pile ��:tlls be dcsicned using [hc eanh press'urc dia_rams <br /> � presen�cd in Pi�urcs 7 ,md S. 'I�he eartlt pressures prosrnted in Pieurc 7 arc for cantilecer walls ���ith <br /> � partial shorim, and sloping bucklill. Pi�,ure S prescnu rccommen��ed :ipp:ucnt earth pressure; lor <br /> full-hcigh[ soldi�r pile wnlls wilh ticbacks. fhc ;ipparcnt c;irth pre;,ure� in I i�we S arc c�pre..cd ;u an <br /> em�elope of the load anJ do not requirc lo;�d factors. <br /> � �I�he ear[h pressures presented in I�igurc 8 includc ihc lu;idin_ fr��m tra(iic surch;�r���. 1��c anticipate tlu �� <br /> partial shorin!s alt�rn;uivc dcpictcd on I�igurc i m:il' bc cconomic;il lur thc c;ut ��;ill uf thc ear:igc �vhiclt is <br /> � off.;et from Oaks Street (if soil nailing is not utiiized). Olher surcharge loacls, such us cranes, construction <br /> � cquipmcnt. or construction staging arc:is. should bc considcrcd b� thc shoring dcsi,,ner on a casc-by-casc <br /> basis. Pigure 9 presents resultine Interal pres,ures from poin[. line, and uniform loads. Seismic pressures <br /> � arc not i�idudcd in Pigures 7 and 3 bccaiisc thc shoring walls will bc tcinporury. <br /> \V'�• recommcnJ that thc embedded purtion ol the soldicr pilcs be tll Icast 2 feet in diametcr and e�[end a <br /> mininwm distancc of 10 �cct bclo�� thc b.isc of thc e�cavation to resist "kick-out.., l hc asial capatit� of <br /> � thc soldicr piles must resist the do�cnw;u'd component of the anchor luads and other ��erticul loads. :�s <br /> � appropriate. �1'c recommend wing an allo�cable end-bearing value of d0 ksf for piles suppo�ticJ un the <br /> J ��cry dense nati�c soils. "I'hc allo��able end bcaring �aluc should be appli�d to tlie base ama o�the drilkd <br /> holc into ��liich Ihc soldi�r pilc is gruutcd. This �aluc incluJcs a ��l'lOf 0� S:t�in of abuut '_.�. If <br /> nccessnry, an allo«�tible pile skin f�riction oF I S ks�ma}' bc us�d en thc embedded portion of the soldicr <br /> piles tu resist dic certical loads. <br /> 1 <br /> iLagging. \1'c recumm�nd that thc tcmporar< timber la!_gin� thickncss (rouehcut) be sized using the tablc <br /> bclo�v as a function ul suldicr pilc clear span and escavatiun depth. T hc la��ein!! thickncsses presen[ed in <br /> f the follu�ving tnblc arc based un procedures outlincd in the Fedcral Fliglt��;iy Administr;ition's <br /> i Gcutcchnical I:ncineerin^ Circular \'o. 3 and �n e.cpu'ience Gom simil:ir es�acations in do��n[own <br /> Sc;udc (scc Grant ct. al, 195-!). <br /> � P 99 9 ( g ) or Gear Spans of: <br /> Df��) 5 feet Recom6 feeded I� '7 feei icknless r8ofee1cut f . �-9 feet � 10 feet�� � <br /> I0 co 25 2 inches 3 inches I 3 inches I 3 inches I�� 4 inches I 4 inches <br /> , 25 to 100 3 inches � 3 inches � 3 inches � 4 inches 4 inches I 5 inches <br /> f I hc �pxc bchinJ thc la�s��ine should be tilled widt soil ur permeable sand slurry as soon a� practical. <br /> � Placcmen[ o( Utis matcrial ��ill help mduce the risk o( coids dc�'�lopim� beLind the ��all and resultant <br /> dam.�ge tu existing improcements' lor,itcd behind the ��';ill. The �corkmanship ,issocia[ed with luegin'� <br /> ! in,tallalion is impor�;mt for m:iintaining the inteerit} ol thc esca�'ation. Lae�im_ should be installed <br /> ; prumptly after esarvation. especiall�� in areas �chere perched :=roundwater is present or �chere clean sand <br /> and �sr.iczl suils .u� present and ca�ine �oils conditions arc likely. <br /> i <br /> i '1'icbacl:s. Tieback ;mchors can be useJ Ibr �vall heighu ��here cantile�er soldier pile �valls are not cost <br /> e(fcctive. Cinback :u�chors shuuld cztcnJ Lu cnough hchind the �vall to develop anchor;ige be}onJ thc <br /> i <br /> nu-load" zone (defincd on Pigure S) �.ind ���ithin a �tuble soil m�ss. �Th� anchors should be inclined <br /> � <br /> � , .,, Ab lll'i.S'-+10�-i�n� Png� 10 GEOENGINEERS� <br /> � �i:iqusT l8. :011l, <br />