五樁樁基承臺計算

1、五樁樁基承臺計算項目名稱 日 期 設計者 校對者一、設計依據(jù)建筑地基基礎(chǔ)設計規(guī)范(GB50007-2011 )&混凝土結(jié)構(gòu)設計規(guī)范(GB50010-2010)建筑樁基技術(shù)規(guī)范(JGJ 94-2008)3二、示意圖三、計算信息承臺類型：五樁承臺計算類型：驗算截面尺寸構(gòu)件編號：CT-11.幾何參數(shù)矩形柱寬bc=500mm矩形柱高hc=500mm圓樁直徑d=400mm承臺根部高度H=800mm承臺端部高度h=800mmx方向樁中心距A=1450mmy方向樁中心距B=800mm承臺邊緣至邊樁中心距C=500mm2.材料信息柱混凝土強度等級：C30 ft_c=1.43N/mm2,fc_c=14.3N/m

2、m2承臺混凝土強度等級：C30 ft_b=1.43N/mm2,fc_b=14.3N/mm2樁混凝土強度等級：C30ft_p=1.43N/mm2,fc_p=14.3N/mm2承臺鋼筋級別：HRB400fy=360N/mm23.計算信息結(jié)構(gòu)重要性系數(shù)：Y o=1.0縱筋合力點至近邊距離：as=80mm作用在承臺頂部荷載基本組合值F=2276.000kNMx=-4.000kN*mMy=18.000kN*mVx=19.000kNVy=4.000kN四、計算參數(shù)承臺總長 Bx=C+2*A+C=0.500+2*1.450+0.500=3.900m承臺總寬 By=C+2*B+C=0.500+2*0.800+

3、0.500=2.600m承臺根部截面有效高度ho=H-as=0.800-0.080=0.720mho1=h-as=0.800-0.080=0.720mh2=H-h=0.800-0.800=0.000m圓樁換算截面寬度 bp=0.8*d=0.8*0.400=0.320m五、內(nèi)力計算各樁編號及定位座標如上圖所示：號樁(x1=-A=-1.450m, y1=-B=-0.800m)號樁(x2=A=1.450m, y2=-B=-0.800m)號樁(x3=A=1.450m, y3=B=0.800m)號樁(x4=-A=-1.450m, y4=B=0.800m)號樁(x5=0, y5=0)各樁凈反力設計值，計算

4、公式：【8.5.3-2Ex =x 2*4=8.410m i 1Ey,=y12*4=2.560mN.=F/n-Mx*y./Ey.2+My*x./Ex.2+Vx*H*x./Ex.2-Vy*H*y1/Ey .2N1=2276.000/5-(-4.000)*(-0.800)/2560+18.000*(-1.450)/8.410+19.000*0.800*(-1.450)/8.410-4.000*0.800*(-0.800)/2.560 =447.226kNN2=2276.000/5-(-4.000)*(-0.800)/2.560+18.000*1.450/8.410 +19.000*0.800*1.4

5、50/8.410-4.000*0.800*(-0.800)/2.560 =458.674kNN3=2276.000/5-(-4.000)*0.800/2.560+18.000*1.450/8.410 +19.000*0.800*1.450/8.410-4.000*0.800*0.800/2.560 =463.174kNN4=2276.000/5-(-4.000)*0.800/2.560+18.000*(-1.450)/8.410 +19.000*0.800*(-1.450)/8.410-4.000*0.800*0.800/2.560 =451.726kNN5=2276.000/5=455.20

6、0kN六、柱對承臺的沖切驗算【8.5.19-1】ENi=N5=455.200kNa ox=A-bc/2-bp/2=1.450-0.500/2-0.320/2=1.040m因 a oxho,所以 a ox=ho=0.720ma oy=B-hc/2-bp/2=0.800-0.500/2-0.320/2=0.390m入 ox=a ox/ho=0.720/0.720=1.000入 oy=a oy/ho=0.390/0.720=0.542a ox=0.84/(入 ox+0.2)=0.84/(1.000+0.2)=0.700a oy=0.84/(入 oy+0.2)=0.84/(0.542+0.2)=1.1

7、33因 H=0.800m 所以 P hp=1.0Y o*Fl=Y o*(F-ENi)=1.0*(2276.000-455.200)=1820.80kN 2*a ox*(hc+a oy)+a oy*(bc+a ox)*p hp*ft_b*ho =2*0.700*(500+390)+1.133*(500+720)*1.000*1.43*720 =4128.19kNY o*Fl=1820.80kN柱對承臺的沖切滿足規(guī)范要求七、 角樁對承臺的沖切驗算【8.5.19-5】Nl=max(N1, N2, N3, N4)=463.174kNa1x=A-bc/2-bp/2=1.450-0.500/2-0.320

8、/2=1.040m因為 a1xho1 所以 a1x=ho1=0.720ma1y=B-hc/2-bp/2=0.800-0.500/2-0.320/2=0.390m入 1x=a1x/ho1=0.720/0.720=1.000入 1y=a1y/ho1=0.390/0.720=0.542P 1x=0.56/(入 1x+0.2)=0.56/(1.000+0.2)=0.467P 1y=0.56/(入 1y+0.2)=0.56/(0.542+0.2)=0.755 C1=C+1/2*bp=0.500+0.320/2=0.660mC2=C+1/2*bp=0.500+0.320/2=0.660m因 h=0.800

9、m 所以 p hp=1.0Y o*Nl=1.0*463.174=463.174kNp 1x*(C2+a1y/2.0)+p 1y*(C1+a1x/2)*p hp*ft_b*ho1= 0.467*(660+390/2)+0.755*(660+720/2)*1.000*1.43*720 =1203.764kNNY o*Nl=463.174kN角樁對承臺的沖切滿足規(guī)范要求八、 承臺斜截面受剪驗算【8.5.21-1 計算承臺計算截面處的計算寬度bx1=Bx=C+2*A+C=0.500+2*1.450+0.500=3.900m bx2=bc=0.500mbxo=1-0.5*h2/ho*(1-bx2/bx1

10、)*bx1=1-0.5*0.000/0.720*(1-0.500/3.900)*3.900=3.900mby1=By=C+2*B+C=0.500+2*0.800+0.500=2.600m by2=hc=0.500mbyo=1-0.5*h2/ho*(1-by2/by1)*by1=1-0.5*0.000/0.720*(1-0.500/2.600)*2.600=2.600m計算剪切系數(shù)因 ho=0.720mW0.800m, P hs=(0.800/0.800)1/=1.0 ax=A-bc/2-bp/2=1.450-0.500/2-0.320/2=1.040m 入 x=ax/ho=1.040/0.72

11、0=1.444P x=1.75/(入 x+1.0)=1.75/(1.444+1.0)=0.716ay=B-hc/2-bp/2=0.800-0.500/2-0.320/2=0.390m入 y=ay/ho=0.390/0.720=0.542P y=1.75/(入 y+1.0)=1.75/(0.542+1.0)=1.135計算承臺底部最大剪力【8.5.21-1 因為 N14=N1+N4=447.226+451.726=898.952kNN23=N2+N3=458.674+463.174=921.848kN所以 Vx=max(|N14|, |N23|)=max(898.952,921.848)=921

12、.848kN因為 N12=N1+N2=447.226+458.674=905.900kNN34=N3+N4=463.174+451.726=914.900kN所以 Vy=max(|N12|, |N34|)=max(905.900,914.900)=914.900kNo*Vx=1.0*921.848=921.848kNP hs*P x*ft_b*byo*ho=1.000*0.716*1.43*2600*720=1916.460kNY o*Vx=921.848kNo*Vy=1.0*914.900=914.900kNp hs*p y*ft_b*bxo*ho=1.000*1.135*1.43*3900

13、*720=4558.067kNY o*Vy=914.900kN承臺斜截面受剪滿足規(guī)范要求九、承臺受彎計算【8.5.21-1】【8.5.21-2】承臺底部彎矩最大值【8.5.21-1】【8.5.21-2因為 Mdx14=(N1+N4)*(A-1/2*bc)= (447.226+451.726)*(1.450-1/2*0.500)=1078.74kN*mMdx23=(N2+N3)*(A-1/2*bc)= (458.674+463.174)*(1.450-1/2*0.500)=1106.22kN*m所以 Mx=max(|Mdx14|, |Mdx23|)=max(|1078.74|,|1106.22|

14、)=1106.22kN*m因為 Mdy12=(N1+N2)*(B-1/2*hc)= (447.226+458.674)*(0.800-1/2*0.500)=498.25kN*mMdy34=(N3+N4)*(B-1/2*hc)= (463.174+451.726)*(0.800-1/2*0.500)=503.20kN*m所以 My=max(|Mdy12|, |Mdy34|)=max(|498.25|,|503.20|)=503.20kN*m計算配筋面積Asx=Y o*Mx/(0.9*ho*fy)=1.0*1106.22*106/(0.9*720*360)=4742.0mm2Asx1=Asx/By=4742.0/3=1824mm2/mAsy=Y o*My/(0.9*ho*fy)=1.0*503.20*106/(0.9*720.000*360)=2157.0mm2Asy1=Asy/Bx=2157.0/4=553mm2/m計算最小配筋率受彎最小配筋率為p min=0.200%承臺最小配筋面積As1min=p min*H*1000=0.200%*800*1000=1600mm2因AslminWAsxl所以 承臺底面x方向配筋面