,室內地面,,,C樁,M樁,地基土,,,層底,平均,

,標高,容重,浮容重,摩阻力,摩阻力,承載力,層底,層厚,埋深,容重,

,7.95,g,g′,qsi,qsi,fak,標高,hi,z,gm,

,,kN/m3,kN/m3,kPa,kPa,kPa,m,m,m,kN/m3,

基底,①雜填土,18.0,水位上,0,,0,5.6,2.35,2.35,14.3,

,①雜填土,18.0,8.0,12,5,20,4.2,1.40,3.75,,

,②1粉質粘土,19.8,9.8,24,15,100,1.0,3.20,6.95,12.2,

,②2淤泥,14.4,4.4,8,5,50,-4.0,5.00,11.95,,

M樁,②4粉質粘土,19.2,9.2,32,16,110,-6.4,2.40,14.35,9.0,

,,,,,,,,,,,,

,,,端阻力,1000,qp,,M樁長∑＝,12.0,,,

,,,,,,,,,,,,

C樁,②4粉質粘土,19.2,9.2,27,16,110,-12.4,6.0,20.35,9.0,

,,,,,,,,,,,,

,,,端阻力,1000,qp,,C樁長∑＝,18.0,,,

,,,,,,,,,,,,

,基礎或樁底面以上土的加權平均重度,,,,gm＝∑gihi／∑hi,,,﹙地下水位以下取浮容重﹚,,,

,,,,,,,,,,,,

,1.確定復合地基承載力特征值fspk,,,,,基底平均壓力,pk＝,250,kPa,,

,《GB50007—2011》5.2.4條,,,,f＝fak＋hbg﹙b－3﹚＋hdgm﹙d－0.5﹚,,,,,,

,《JGJ79—2012》3.0.4條,,,,寬度修正,hb＝,0,,深度修正,hd＝,1.0

,,則,,,,"地基承載力特征值,深度修正",f＝fak＋hdgm﹙d－0.5﹚,,,,

,,根據(jù),,,,,fsp＝fspk＋hdgm﹙d－0.5﹚≥,pk,,,

,,得,,,,,fspk＝pk－h(huán)dgm﹙d－0.5﹚,,,,

,,,,,,,,,,,,

,室內外高差,△h＝,0.45,m,填土層,,②1層,,淤泥層,,

,,,,,,,,,,,,

,,,室內埋深,D＝,2.35,,3.75,,6.95,m,

,,室外埋深,,d＝D－△h＝,1.90,,3.30,,6.50,m,

,,,,fspk＝pk－h(huán)dgm﹙d－0.5﹚＝,230,,210,,177,kPa,

,,,,,,,,,,,,

,,,取,fspk＝,230,,210,,200,kPa,

,,,,,,,,,,,,

,2.確定樁徑d、樁長l，褥墊層厚度d′,,,,,,,,取褥墊層厚度d′＝,0.3,m

,,,,,,,,,,,,

,,,C樁樁徑d＝,400,㎜＝,0.4,m,,upc＝pd＝,1.26,m

,,,C樁長l＝,18.0,m,,,,Apc＝pd2／4＝,0.13,m2

,,,,,,,,,,,,

,,,M樁樁徑d＝,400,㎜＝,0.4,m,,upm＝pd＝,1.26,m

,,,樁長l＝,12.0,m,,,,Apm＝pd2／4＝,0.13,m2

,,,,,,,,,,,,

,3.確定單樁承載力特征值Ra,,,,,,,,,,

,⑴C樁承載力特征值Rac,,,"根據(jù)《DBJ／T15—79—2011》4.3.2條,",,,,,,,

,按,,,,Rac＝upc∑qsihi＋aqpApc,確定,,,a＝,0.85,

,得，C樁,,,,Rac＝up∑qsihi＋aqpApc＝,575,kN,,,,

,,,,,,,,,,,,

,"根據(jù)《DBJ／T15—79—2011》4.3.3條,按",,,,,,,Rac＝fcuApc／3,確定,,

,,,設樁身強度,,fcu＝,20,MPa,﹙C25﹚,,,

,,則,,,Rac＝fcuApc／3＝,628,kN,,,,

,,,,,,,,,,,,

,,,,C樁，取,Rac＝,600,kN,,,,

,,,,,,,,,,,,

,⑵M樁承載力特征值Ram,,,,,,,,,,

,"根據(jù)《DBJ／T15—79—2011》4.3.5條,按",,,,,,,,Ram＝upm∑qsihi＋aqpApm,確定,

,得,,,,Ram＝upm∑qsihi＋aqpApc＝,224,kN,,a＝,0.6,

,,,,,,,,,,,,

,及,Ram＝hfcukApm確定,,,,,,,h＝,0.25,

,,,,,,,,,,,,

,,,,,填土層,,②1層,,淤泥層,,

,,,設樁身強度,fcuk＝,1.00,,1.60,,0.80,MPa,

,,,,,,,,,,,,

,,,,則Ram＝hfcukApm＝,31,,50,,25,kN,

,,,,,,,,,,,,

,,,取,Ram＝,30,,50,,25,kN,

,,,,,,,,,,,,

,4.確定樁土面積置換率m,,,按《DBJ／T15—79—2011》4.3.1條,,,,,,,

,由公式,fspk＝hcmcRac／Apc＋hmmmRam／Apm＋hs﹙1－mc－mm﹚fak,,,,,,,,,推得

,,,,,,,,,,,,

,布樁單元尺寸,,,單元長度ax＝,2.2,m,,參于工作系數(shù),,,

,,,,條基寬度ay＝,3.2,m,C樁,hc＝,0.80,,

,,,,A0＝axay＝,7.04,㎡,M樁,hm＝,0.90,,

,,,,C樁根數(shù)nc＝,3,,土,hs＝,1.00,,

,,,,M樁根數(shù)nm＝,3,,,,,,

,,,,,,,,,,,,

,,,,C樁置換率mc＝ncApc／A0＝,0.053549875,,,,,,

,,,,M樁置換率mm＝nmApm／A0＝,0.053549875,,,,,,

,,,,,,,,,,,,

,,,,,填土層,,②1層,,淤泥層,,

,,,,fak＝,20,,100,,50,kPa,

,,,,,,,,,,,,

,,,,hcmcRac／Apc＝,205,,205,,205,kPa,

,,,,hmmmRam／Apm＝,12,,19,,10,kPa,

,,,,hs﹙1－mc－mm﹚fak＝,1