2.1.5 梯板厚度 h1 = Lo / 27 = 274mm ,取 h1 = 270mm
2.1.6 踏步段总高度 Hs = 1750mm 楼梯踏步级数 n = 14
2.1.7 线性恒荷标准值 Pk = 1kN/m 均布活荷标准值 qk = 2kN/m ψc = 0.7
ψq = 0.4
2.1.8 面层厚度 c1 = 25mm 面层容重 γc1 =20kN/m 顶棚厚度 c2 = 20mm
顶棚容重 γc2 =18kN/m
2.1.9 楼梯自重容重 γb = 25kN/m
2.1.10 混凝土强度等级: C30 fc = 14.33N/mm ft = 1.43N/mm
ftk = 2.01N/mm Ec = 29791N/mm
2.1.11 钢筋强度设计值 fy = 360N/mm Es = 200000N/mm
纵筋合力点至近边距离 as = 25mm
2.2 楼梯几何参数
2.2.1 踏步高度 hs = Hs / n = 1750/14 = 125mm
踏步宽度 bs = Lsn / (n - 1) = 3250/(14-1) = 250mm
踏步段斜板的倾角 α = ArcTan(hs / bs) = ArcTan(125/250) = 26.6°
踏步段斜板的长度 Lx = Lsn / Cosα = 3250/Cos26.6°= 3634mm
2.2.2 踏步段梯板厚的垂直高度 h1' = h1 / Cosα = 270/Cos26.6°= 302mm
踏步段梯板平均厚度 T = (hs + 2 * h1') / 2 = (125+2*302)/2 = 364mm
2.2.3 梯板有效高度 h1o = h1 - as = 270-25 = 245mm
2.3 均布永久荷载标准值
2.3.1 梯板上的线形荷载换算成均布永久荷载 gk1 = Pk / B = 1/1.15 = 0.87kN/m
2.3.2 踏步段梯板自重 gk2' = γb * T = 25*0.364 = 9.11kN/m
gk2 = gk2' * Lsn / Ln = 9.11*3.25/7.2 = 4.11kN/m
2.3.3 低端、高端平板自重 gk3' = γb * h1 = 25*0.27 = 6.75kN/m
gk3 = gk3' * (Lln + Lhn) / Ln = 6.75*(1.95+2)/7.2 = 3.70kN/m
2.3.4 踏步段梯板面层自重
gk4' = γc1 * c1 * [n * hs + (n - 1) * bs] / Lsn
= 20*0.025*[14*0.125+(14-1)*0.25]/3.25 = 0.77kN/m
gk4 = gk4' * Lsn / Ln = 0.77*3.25/7.2 = 0.35kN/m
2.3.5 低端、高端平板面层自重 gk5' = γc1 * c1 = 20*0.025 = 0.50kN/m
gk5 = gk5' * (Lln + Lhn) / Ln = 0.5*(1.95+2)/7.2 = 0.27kN/m
2.3.6 梯板顶棚自重 gk6' = γc2 * c2 = 18*0.02 = 0.36kN/m
gk6 = gk6' * (Ln + Lx - Lsn) / Ln = 0.36*(7.2+3.634-3.25)/7.2 = 0.38kN/m
2.3.7 均布荷载标准值汇总 gk = gk1 + gk2 + gk3 + gk4 + gk5 + gk6 = 9.69kN/m
2.4 均布荷载设计值
由可变荷载控制的 p(L) = 1.2 * gk + 1.4 * qk = 14.42kN/m
由永久荷载控制的 p(D) = 1.35 * gk + 1.4 * ψc * qk = 15.04kN/m
最不利的荷载设计值 p = Max{p(L), p(D)} = 15.04kN/m
2.5 支座反力
永久荷载作用下均布反力标准值 Rk(D) = 34.87kN/m 六层现浇钢筋混凝土框架结构员工培训中心建筑与结构设计(66):http://www.youerw.com/gongcheng/lunwen_210.html