板式楼梯计算表

一、常规数据板倾角cosα=1/(1+(hstep/bstep)2)1/2面层 0.65*(bstep+hstep)/bstep踏步 25hstep/2恒荷斜板 25h/cosα载板底抹灰 0.34/cosα栏杆恒荷载标准值gK (KN/m)总荷载设计值p=1.2gK+1.4qK (KN/m)0.8811.001.885.110.390.408.7615.42混凝土轴心抗压设计值fc (N/mm2)系数α1混凝土抗拉标准值ftk (N/mm2)2混凝土弹性模量EC (N/mm)梯段板厚h=ln/25 (mm)梯段板厚实际取值h (mm)有效厚度h0=h-15-d/2 (mm)板计算跨度l0=1.05ln (mm)14.31.002.013.0E+04171.21801574494二、截面配筋弯矩M=pl02/8 (KN·m)截面抵抗矩系数αS=M/α1fcbh02γS=(1+(1-2αS)1/2)/2钢筋面积AS=M/γSfyh0 (mm2)38.920.11040.9414877.8钢筋直径d (mm)钢筋间距s (mm)钢筋实际配筋面积AS (mm2)是否满足161251608.5满足三、裂缝验算ρte=AS/0.5bh30.960.0179短期弯矩MS=(gK+qK)l02/8 (KN·m)ρte实际取值(ρte≥0.01)0.0179长期弯矩Ml=(gK+ψqqK)l02/8 (KN·m)26.542140.92受拉区纵筋等效直径deq=d/ν (mm)22.9σsk=MS/ηh0AS (N/mm)ψ=1.1-0.65ftk/ρteσsk应变不均匀系数ψ实际取值(0.2≤ψ≤1.0)0.5810.581最外层受拉钢筋外边缘至受拉底边距离c (20≤c≤65) (mm)20最大裂缝宽度ωmax=αcrψσsk/ES(1.9c+0.08deq/ρte) (mm)0.12最大裂缝宽度限值ωlim (mm)验算ωmax ≤ ωlim0.30满足四、挠度验算αEρ=ESAS/ECbh0短期刚度BS=ESASh02/(1.15ψ+0.2+6αEρ) (N·mm2)长期刚度Bl=BS*MS/(MS+Ml) (N·mm2)2挠度限值 l0/20019.50挠度f=5MSl0/48Bl (mm)验算f ≤ l0/2000.0686.20E+123.34E+1222.5满足