ψ = 1.1 - 0.65 * ftk / (ρte * σsq) (混凝土规范式 7.1.2-2)
σsq = Mq / (0.87 * ho * As) (混凝土规范式 7.1.4-3)
σsq = 8.66*10^6/(0.87* 76.* 503.) = 260.478N/mm2
矩形截面,Ate=0.5*b*h=0.5*1000*100.= 50000.mm2
ρte = As / Ate (混凝土规范式 7.1.2-4)
ρte = 503./ 50000.= 0.010
ψ = 1.1 - 0.65* 2.01/( 0.01* 260.48) = 0.602
ωmax = αcr*ψ*σsq/Es*(1.9c+0.08*Deq/ρte) (混凝土规范式 7.1.2-1)
ωmax =1.9*0.602*260.478/200000.*(1.9*20.+0.08* 8.00/0.01005) = 0.151mm,满足规范要求!
⑤、右端支座跨中裂缝:
裂缝间纵向受拉钢筋应变不均匀系数 ψ, 按下列公式计算:
ψ = 1.1 - 0.65 * ftk / (ρte * σsq) (混凝土规范式 7.1.2-2)
σsq = Mq / (0.87 * ho * As) (混凝土规范式 7.1.4-3)
σsq = 12.50*10^6/(0.87* 74.* 754.) = 257.547N/mm2
矩形截面,Ate=0.5*b*h=0.5*1000*100.= 50000.mm2
ρte = As / Ate (混凝土规范式 7.1.2-4)
ρte = 754./ 50000.= 0.015
ψ = 1.1 - 0.65* 2.01/( 0.02* 257.55) = 0.764
ωmax = αcr*ψ*σsq/Es*(1.9c+0.08*Deq/ρte) (混凝土规范式 7.1.2-1)
ωmax =1.9*0.764*257.547/200000.*(1.9*20.+0.08*12.00/0.01508) = 0.190mm,满足规范要求!
3.内力计算
3.1竖向荷载计算
3.2 水平荷载计算
3.2.1 风荷载计算
已知基本风压0.55KN/m2。地面粗糙度属B类。