当前位置:文档之家› 某楼梯计算书(结构设计)

某楼梯计算书(结构设计)

1 板式楼梯: TB11.1 基本资料1.1.1 工程名称: 工程一1.1.2 楼梯类型: 板式 A 型 ( ╱ ),支座条件: 两端弹性1.1.3 踏步段水平净长 L sn = 2520mm ,梯板净跨度 L n = L sn = 2520mm , 梯板净宽度 B = 2350mm1.1.4 低端支座宽度 d l = 200mm ,高端支座宽度 d h = 200mm计算跨度 L 0 = Min{L n + (d l + d h ) / 2, 1.05L n } = Min{2720, 2646} = 2646mm 1.1.5 梯板厚度 h 1 = 120mm1.1.6 踏步段总高度 H s = 1500mm ,楼梯踏步级数 n = 101.1.7 线性恒荷标准值 P k = 1kN/m ; 均布活荷标准值 q k = 3.5kN/m ψc = 0.7, ψq = 0.41.1.8 面层厚度 c 1 = 25mm ,面层容重 γc2 = 20kN/m 顶棚厚度 c 2 = 20mm , 顶棚容重 γc2 = 18kN/m 楼梯自重容重 γb =25kN/m 1.1.9 混凝土强度等级为 C30, f c = 14.331N/mm f t = 1.433N/mm f tk = 2.006N/mm E c = 29791N/mm 1.1.10 钢筋抗拉强度设计值 f y = 360N/mm E s =200000N/mm 纵筋的混凝土保护层厚度 c = 15mm1.2 楼梯几何参数1.2.1 踏步高度 h s = H s / n = 1500/10 = 150mm踏步宽度 b s = L sn / (n - 1) = 2520/(10-1) = 280mm踏步段斜板的倾角 α = ArcTan(h s / b s ) = ArcTan(150/280) = 28.2° 踏步段斜板的长度 L x = L sn / Cos α = 2520/Cos28.2° = 2859mm1.2.2 踏步段梯板厚的垂直高度 h 1' = h 1 / Cos α = 120/Cos28.2° = 136mm 踏步段梯板平均厚度 T = (h s + 2h 1') / 2 = (150+2*136)/2 = 211mm 1.2.3 梯板有效高度 h 10 = h 1 - a s = 120-20 = 100mm1.3 均布永久荷载标准值1.3.1 梯板上的线载换算为均布恒荷 g k1 = P k / B = 1/2.35 = 0.43kN/m 1.3.2 梯板自重 g k2 = γb ·T = 25*0.211 = 5.28kN/m 1.3.3 踏步段梯板面层自重g k3 = γc1·c 1·(n - 1)(h s + b s ) / L n = 20*0.025*(10-1)*(0.15+0.28)/2.52 = 0.77kN/m1.3.4 梯板顶棚自重 g k4' = γc2·c 2 = 18*0.02 =0.36kN/m g k4 = g k4'·L x / L n = 0.36*2.859/2.52 = 0.41kN/m1.3.5 均布荷载标准值汇总 g k = g k1 + g k2 + g k3 + g k4 = 6.88kN/m1.4 均布荷载的基本组合值由可变荷载控制的 Q(L) = γG ·g k + γQ ·q k = 1.2*6.88+1.4*3.5 = 13.16kN/m 由永久荷载控制的 Q(D) = γG1·g k + γQ ·ψc · q k = 1.35*6.88+1.4*0.7*3.5 = 12.72kN/m最不利的荷载基本组合值 Q = Max{Q(L), Q(D)} = Max{13.16, 12.72} = 13.16kN/m1.5 梯板的支座反力永久荷载作用下均布反力标准值 R k (D) = 8.67kN/m 可变荷载作用下均布反力标准值 R k (L) = 4.41kN/m 最不利的均布反力基本组合值 R = 16.58kN/m1.6 梯板斜截面受剪承载力计算 V ≤ 0.7·βh ·f t ·b ·h 0V = 0.5·Q ·L n ·Cos α = 0.5*13.16*2.52*Cos28.2° = 14.6kNR = 0.7·βh ·f t ·b ·h 0 = 0.7*1*1433*1*0.1 = 100.3kN ≥ V = 14.6kN ,满足要求。

1.7 正截面受弯承载力计算1.7.1 跨中 M max = Q ·L 02 / 10 = 13.16*2.6462/10 = 9.21kN ·m A s = 262mm a s = 19mm ,ξ = 0.065,ρ = 0.26%; 实配纵筋:10@200 (A s = 393); 最大裂缝宽度 ωmax = 0.209mm1.7.2 支座 M min = -Q ·L 02 / 20 = -13.16*2.6462/20 = -4.61kN ·m A s = 129mm a s = 19mm ,ξ = 0.032,ρ = 0.13%; ρmin = 0.20%, A s,min = 240mm 实配纵筋:10@200 (A s = 393); 最大裂缝宽度 ωmax = 0.054mm1.8 跨中挠度验算 1.8.1 挠度验算参数按荷载效应的标准组合计算的弯矩值 M k = 7.27kN ·m 按荷载效应的准永久组合计算的弯矩值 M q = 5.80kN ·m 1.8.2 荷载效应的标准组合作用下受弯构件的短期刚度 B s 1.8.2.1 裂缝间纵向受拉钢筋应变不均匀系数 ψσsk = M k / (0.87h 0·A s ) (混凝土规范式 8.1.3-3) σsk = 7267478/(0.87*101*279) = 296N/mm矩形截面,A te = 0.5·b ·h = 0.5*1000*120 = 60000mm ρte = A s / A tk (混凝土规范式 8.1.2-4)ρte = 279/60000 = 0.00465 <0.01,取 ρte = 0.01ψ = 1.1 - 0.65f tk / (ρte ·σsk ) (混凝土规范式 8.1.2-2) ψ = 1.1-0.65*2.01/(0.01*296) = 0.661.8.2.2 钢筋弹性模量与混凝土模量的比值: αE = E s / E c = 200000/29791 = 6.71 1.8.2.3 受压翼缘面积与腹板有效面积的比值 γf ' 矩形截面,γf ' = 01.8.2.4 纵向受拉钢筋配筋率 ρ = A s / (b ·h 0) = 279/(1000*101) = 0.00276 1.8.2.5 钢筋混凝土受弯构件的短期刚度 B s 按混凝土规范式 8.2.3-1 计算:B s = E s ·A s ·h 02/ [1.15ψ + 0.2 + 6·αE ·ρ / (1 + 3.5γf ')]= 200000*279*1012/[1.15*0.66+0.2+6*6.71*0.00276/(1+3.5*0)] = 532.42kN ·m 1.8.3 考虑荷载长期效应组合对挠度影响增大影响系数 θ按混凝土规范第 8.2.5 条,当 ρ' = 0 时,取 θ = 2.0 1.8.4 受弯构件的长期刚度 B 按混凝土规范式 8.2.2 计算:B = B s ·M k / [M q ·(θ - 1) + M k ] = 532.42*7.27/[5.8*(2-1)+7.27] = 296.17kN ·m 1.8.5 跨中挠度 f挠度验算时考虑踏步刚度,踏步段等效高度 h eq = 131mm ,挠度折减系数 η = 0.7957f = 0.7957·2.9/384·Q k ·L 04 / B = 0.00601*10.38*2.6464/296.17*1000 = 10.3mm f/L 0 = 10.3/2646 = 1/2561.9 板式楼梯平面整体表示方法的注写内容 AT1, h = 120 150X10 =1500 10@2002 板式楼梯: TB22.1 基本资料2.1.1 工程名称: 工程一2.1.2 楼梯类型: 板式 A 型 ( ╱ ),支座条件: 两端弹性2.1.3 踏步段水平净长 L sn = 3920mm ,梯板净跨度 L n = L sn = 3920mm , 梯板净宽度 B = 1400mm2.1.4 低端支座宽度 d l = 200mm ,高端支座宽度 d h = 200mm计算跨度 L 0 = Min{L n + (d l + d h ) / 2, 1.05L n } = Min{4120, 4116} = 4116mm 2.1.5 梯板厚度 h 1 = 150mm2.1.6 踏步段总高度 H s = 2250mm ,楼梯踏步级数 n = 152.1.7 线性恒荷标准值 P k = 1kN/m ; 均布活荷标准值 q k =3.5kN/m ψc = 0.7, ψq = 0.42.1.8 面层厚度 c 1 = 25mm ,面层容重 γc2 = 20kN/m 顶棚厚度 c 2 = 20mm , 顶棚容重 γc2 = 18kN/m 楼梯自重容重 γb =25kN/m 2.1.9 混凝土强度等级为 C30, f c = 14.331N/mm f t = 1.433N/mm f tk = 2.006N/mm E c = 29791N/mm 2.1.10 钢筋抗拉强度设计值 f y = 360N/mm E s =200000N/mm 纵筋的混凝土保护层厚度 c = 15mm2.2 楼梯几何参数2.2.1 踏步高度 h s = H s / n = 2250/15 = 150mm踏步宽度 b s = L sn / (n - 1) = 3920/(15-1) = 280mm踏步段斜板的倾角 α = ArcTan(h s / b s ) = ArcTan(150/280) = 28.2° 踏步段斜板的长度 L x = L sn / Cos α = 3920/Cos28.2° = 4447mm2.2.2 踏步段梯板厚的垂直高度 h 1' = h 1 / Cos α = 150/Cos28.2° = 170mm 踏步段梯板平均厚度 T = (h s + 2h 1') / 2 = (150+2*170)/2 = 245mm 2.2.3 梯板有效高度 h 10 = h 1 - a s = 150-20 = 130mm2.3 均布永久荷载标准值 2.3.1 梯板上的线载换算为均布恒荷 g k1 = P k / B = 1/1.4 = 0.71kN/m 2.3.2 梯板自重 g k2 = γb ·T = 25*0.245 =6.13kN/m 2.3.3 踏步段梯板面层自重g k3 = γc1·c 1·(n - 1)(h s + b s ) / L n = 20*0.025*(15-1)*(0.15+0.28)/3.92 = 0.77kN/m2.3.4 梯板顶棚自重 g k4' = γc2·c 2 = 18*0.02 = 0.36kN/m g k4 = g k4'·L x / L n = 0.36*4.447/3.92 =0.41kN/m2.3.5 均布荷载标准值汇总 g k = g k1 + g k2 + g k3 + g k4 = 8.02kN/m2.4 均布荷载的基本组合值由可变荷载控制的 Q(L) = γG ·g k + γQ ·q k = 1.2*8.02+1.4*3.5 = 14.52kN/m 由永久荷载控制的 Q(D) = γG1·g k + γQ ·ψc · q k = 1.35*8.02+1.4*0.7*3.5 = 14.26kN/m最不利的荷载基本组合值 Q = Max{Q(L), Q(D)} = Max{14.52, 14.26} = 14.52kN/m2.5 梯板的支座反力永久荷载作用下均布反力标准值 R k (D) = 15.72kN/m 可变荷载作用下均布反力标准值 R k (L) = 6.86kN/m 最不利的均布反力基本组合值 R = 28.47kN/m2.6 梯板斜截面受剪承载力计算 V ≤ 0.7·βh ·f t ·b ·h 0V = 0.5·Q ·L n ·Cos α = 0.5*14.52*3.92*Cos28.2° = 25.1kNR = 0.7·βh ·f t ·b ·h 0 = 0.7*1*1433*1*0.13 = 130.4kN ≥ V = 25.1kN ,满足要求。

相关主题