矩形板式桩基础计算书计算依据：1、《塔式起重机混凝土基础工程技术标准》JGJ/T187-20192、《混凝土结构设计规范》GB50010-20103、《建筑桩基技术规范》JGJ94-20084、《建筑地基基础设计规范》GB50007-20115、《预应力混凝土管桩技术标准》JGJ/T406-2017一、塔机属性二、塔机荷载1、塔机传递至基础荷载标准值2、塔机传递至基础荷载设计值三、桩顶作用效应计算承台底标高d1(m) -4基础布置图承台及其上土的自重荷载标准值：G k=bl(hγc+h'γ')=6.5×6.5×(1.4×25+0×19)=1478.75kN承台及其上土的自重荷载设计值：G=1.35G k=1.35×1478.75=1996.312kN 桩对角线距离：L=(a b2+a l2)0.5=(4.82+4.82)0.5=6.788m1、荷载效应标准组合轴心竖向力作用下：Q k=(F k'+G k)/n=(558+1478.75)/4=509.188kN荷载效应标准组合偏心竖向力作用下：Q kmax=(F k'+G k)/n+(M k'+F Vk'h)/L=(558+1478.75)/4+(2322+86×1.4)/6.788=868.987kNQ kmin=(F k'+G k)/n-(M k'+F Vk'h)/L=(558+1478.75)/4-(2322+86×1.4)/6.788=149.388kN2、荷载效应基本组合荷载效应基本组合偏心竖向力作用下：Q max=(F'+G)/n+(M'+F v'h)/L=(753.3+1996.312)/4+(3134.7+116.1×1.4)/6.788=1173.132kN Q min=(F'+G)/n-(M'+F v'h)/L=(753.3+1996.312)/4-(3134.7+116.1×1.4)/6.788=201.674kN 四、桩承载力验算1、桩基竖向抗压承载力计算桩身周长：u=πd=3.14×0.5=1.571mh b/d=1×1000/500=2<5λp=0.16h b/d=0.16×2=0.32空心管桩桩端净面积：A j=π[d2-(d-2t)2]/4=3.14×[0.52-(0.5-2×0.125)2]/4=0.147m2 空心管桩敞口面积：A p1=π(d-2t)2/4=3.14×(0.5-2×0.125)2/4=0.049m2承载力计算深度：min(b/2,5)=min(6.5/2,5)=3.25mf ak=(0.55×260)/3.25=143/3.25=44kPa承台底净面积：A c=(bl-n(A j+A p1))/n=(6.5×6.5-4×(0.147+0.049))/4=10.366m2复合桩基竖向承载力特征值：R a=ψuΣq sia·l i+q pa·(A j+λp A p1)+ηc f ak A c=0.8×1.571×(2.7×12+1.5×70+6.1×40+0.7×80)+350 0×(0.147+0.32×0.049)+0.1×44×10.366=1164.715kNQ k=509.188kN≤R a=1164.715kNQ kmax=868.987kN≤1.2R a=1.2×1164.715=1397.658kN满足要求！2、桩基竖向抗拔承载力计算Q kmin=149.388kN≥0不需要进行桩基竖向抗拔承载力计算！3、桩身承载力计算纵向预应力钢筋截面面积：A ps=nπd2/4=15×3.142×10.72/4=1349mm2(1)、轴心受压桩桩身承载力荷载效应基本组合下的桩顶轴向压力设计值：Q=Q max=1173.132kN 桩身结构竖向承载力设计值：R=1500kNQ=1173.132kN≤1500kN满足要求！(2)、轴心受拔桩桩身承载力Q kmin=149.388kN≥0不需要进行轴心受拔桩桩身承载力计算！4、裂缝控制计算Q kmin=149.388kN≥0不需要进行裂缝控制计算！五、承台计算1、荷载计算承台计算不计承台及上土自重:F max=F/n+M/L=753.3/4+3134.7/6.788=650.11kNF min=F/n-M/L=753.3/4-3134.7/6.788=-273.46kN承台底部所受最大弯矩:M x= F max (a b-B)/2=650.11×(4.8-1.8)/2=975.165kN.mM y= F max (a l-B)/2=650.11×(4.8-1.8)/2=975.165kN.m承台顶部所受最大弯矩:M'x= F min (a b-B)/2=-273.46×(4.8-1.8)/2=-410.19kN.mM'y= F min (a l-B)/2=-273.46×(4.8-1.8)/2=-410.19kN.m计算底部配筋时：承台有效高度：h0=1400-50-22/2=1339mm计算顶部配筋时：承台有效高度：h0=1400-50-22/2=1339mm2、受剪切计算V=F/n+M/L=753.3/4 + 3134.7/6.788=650.11kN受剪切承载力截面高度影响系数：βhs=(800/1339)1/4=0.879塔吊边缘至角桩内边缘的水平距离：a1b=(a b-B-d)/2=(4.8-1.8-0.5)/2=1.25ma1l=(a l-B-d)/2=(4.8-1.8-0.5)/2=1.25m剪跨比：λb'=a1b/h0=1250/1339=0.934，取λb=0.934；λl'= a1l/h0=1250/1339=0.934，取λl=0.934；承台剪切系数：αb=1.75/(λb+1)=1.75/(0.934+1)=0.905αl=1.75/(λl+1)=1.75/(0.934+1)=0.905βhsαb f t bh0=0.879×0.905×1.57×103×6.5×1.339=10873.203kNβhsαl f t lh0=0.879×0.905×1.57×103×6.5×1.339=10873.203kNV=650.11kN≤min(βhsαb f t bh0，βhsαl f t lh0)=10873.203kN满足要求！3、受冲切计算塔吊对承台底的冲切范围：B+2h0=1.8+2×1.339=4.478ma b=4.8m>B+2h0=4.478m，a l=4.8m>B+2h0=4.478m角桩内边缘至承台外边缘距离：c b=(b-a b+d)/2=(6.5-4.8+0.5)/2=1.1mc l=(l-a l+d)/2=(6.5-4.8+0.5)/2=1.1m角桩冲跨比：：λb''=a1b/h0=1250/1339=0.934，取λb=0.934；λl''= a1l/h0=1250/1339=0.934，取λl=0.934；角桩冲切系数：β1b=0.56/(λb+0.2)=0.56/(0.934+0.2)=0.494β1l=0.56/(λl+0.2)=0.56/(0.934+0.2)=0.494[β1b(c b+a lb/2)+β1l(c l+a ll/2)]βhp·f t·h0=[0.494×(1.1+1.25/2)+0.494×(1.1+1.25/2)]×0.95×157 0×1.339=3403.902kNN l=V=650.11kN≤[β1b(c b+a lb/2)+β1l(c l+a ll/2)]βhp·f t·h0=3403.902kN满足要求！4、承台配筋计算(1)、承台底面长向配筋面积αS1= M y/(α1f c bh02)=975.165×106/(1×16.7×6500×13392)=0.005ζ1=1-(1-2αS1)0.5=1-(1-2×0.005)0.5=0.005γS1=1-ζ1/2=1-0.005/2=0.997A S1=M y/(γS1h0f y1)=975.165×106/(0.997×1339×300)=2434mm2最小配筋率：ρ=0.15%承台底需要配筋：A1=max(A S1, ρbh0)=max(2434,0.0015×6500×1339)=13056mm2 承台底长向实际配筋：A S1'=15824mm2≥A1=13056mm2满足要求！(2)、承台底面短向配筋面积αS2= M x/(α2f c lh02)=975.165×106/(1×16.7×6500×13392)=0.005ζ2=1-(1-2αS2)0.5=1-(1-2×0.005)0.5=0.005γS2=1-ζ2/2=1-0.005/2=0.997A S2=M x/(γS2h0f y1)=975.165×106/(0.997×1339×300)=2434mm2最小配筋率：ρ=0.15%承台底需要配筋：A2=max(A S2, ρlh0)=max(2434,0.0015×6500×1339)=13056mm2 承台底短向实际配筋：A S2'=15824mm2≥A2=13056mm2满足要求！(3)、承台顶面长向配筋面积αS1= M'y/(α1f c bh02)=410.19×106/(1×16.7×6500×13392)=0.002ζ1=1-(1-2αS1)0.5=1-(1-2×0.002)0.5=0.002γS1=1-ζ1/2=1-0.002/2=0.999A S3=M'y/(γS1h0f y1)=410.19×106/(0.999×1339×300)=1023mm2最小配筋率：ρ=0.15%承台顶需要配筋：A3=max(A S3,ρbh0,0.5A S1')=max(1023,0.0015×6500×1339,0.5×15824)=13056mm2 承台顶长向实际配筋：A S3'=15824mm2≥A3=13056mm2满足要求！(4)、承台顶面短向配筋面积αS2= M'x/(α2f c lh02)=410.19×106/(1×16.7×6500×13392)=0.002ζ2=1-(1-2αS2)0.5=1-(1-2×0.002)0.5=0.002γS2=1-ζ2/2=1-0.002/2=0.999A S4=M'x/(γS2h0f y1)=410.19×106/(0.999×1339×300)=1023mm2最小配筋率：ρ=0.15%承台顶需要配筋：A4=max(A S4, ρlh0,0.5A S2' )=max(1023,0.0015×6500×1339,0.5 ×15824)=13056mm2承台顶面短向配筋：A S4'=15824mm2≥A4=13056mm2满足要求！(5)、承台竖向连接筋配筋面积承台竖向连接筋为双向HPB300 10@500。