梁抗扭计算表

1.基本参数,,单位,,,,单位,

混凝土强度等级,25,,,弯矩M=,18.8,kN.m,

扭矩T=,7.3,kN.m,,V=,16,kN,

Astl=,804,mm2,,Ast1=,50.3,mm2,

保护层厚度c=,25,mm,,as=,35,mm,

ft=,1.27,N/mm2,,fc=,11.9,N/mm2,

fyv=,300,N/mm2,,fy=,300,N/mm2,

b=,250,mm,,h=,400,mm,

bcor=,200,mm,,hcor=,350,mm,

Acor=,70000,mm2,,Ucor=,1100,mm,

Wt=b2/6*(3h-b),9895833.333,mm3,,,,,

ρtl=Astl/b/h=,0.804,,,,,,

,,,,,,,,

2.验算截面尺寸,,,,,,,

hw=h0=,365,mm,,hw/b=,1.46,<,4

V/bh0+T/0.8Wt=,1.097447729,N/mm2,<,0.25βcfc=,2.975,N/mm2,截面符合要求

3.验算是否可不考虑剪力,,,,,,,

0.35ftbh0=,40.560625,kN,>,V=,16,kN,可忽略剪力

4.验算是否可不考虑扭矩,,,,,,,

0.175ftWt=,2.199348958,kN.m,<,扭矩T=,7.3,kN.m,不能忽略扭矩

5.验算是否按计算配置抗剪、抗扭钢筋,,,,,,,

V/bh0+T/Wt=,,N/mm2,>,0.7ft=,0.889,N/mm2,应按计算配置抗剪、抗扭钢筋

6.计算剪扭构件混凝土承载力降低系数βt,,,,,,,

βt=1.5/(1+0.5VWt/Tbh0=,1.340666406,,>,,1,取βt=,1

7.计算箍筋用量,,,,,,,

1）计算抗扭箍筋用量,,,,,,,

取ζ=,1,,,,,,

Ast1/s=(T-0.35ftWt)/(1.2*ζ^0.5*fyv*Acor)=,0.115,,,s=,436.5936816,,

2）计算抗剪箍筋用量,,,,,,,

Asv1/s=(V-0.7(1.5-βt)ftbh0)/(1.25fyvh0)=,-0.090,,,,,,

3）抗剪和抗扭箍筋用量,,,,,,,

Asv1'/s=Asv1/s+Ast1/s=,0.296,,,,,,

选用箍筋直径φ=,8,mm,,单支箍筋面积Asv1'=,50.3,,

箍筋间距s=,169.6248002,mm,,取s=,160,,

4）验算配箍率,,,,,,,

"ρsv,min=0.28*ft/fyv=",0.118533333,,<,配箍率ρsv=Asv/bs=,0.251327412,,满足要求

8.计算抗扭纵筋用量,,,,,,,

1）求Astl,,,,,,,

Astl=ζ*fyv*Ast1*ucor/fy/s=,343.1,,抗扭纵筋根数,2,,,

选=,2,φ,16,,,,

As=,402.1238597,>,343.1,满足要求,,,

2）验算配筋率,,,,,,,

受扭纵向钢筋的配筋率ρtl=Astl/bh=,0.40212386,,,,,,

T/Vb=,1.825,T=,1.825,,