资源描述
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1.受弯构件:
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度等级:C30 fc = 14.33N/mm ft = 1.43N/mm
1.1.3 钢筋强度设计值 fy = 360N/mm Es = 200000N/mm
1.1.4 由弯矩设计值 M 求配筋面积 As,弯矩 M = 120kN·m
1.1.5 截面尺寸 b×h = 250*500mm ho = h - as = 500-40 = 460mm
1.2 计算结果:
1.2.1 相对界限受压区高度 ξb
ξb = β1 / [1 + fy / (Es * εcu)] = 0.8/[1+360/(200000*0.0033)] = 0.518
1.2.2 受压区高度 x = ho - [ho ^ 2 - 2 * M / (α1 * fc * b)] ^ 0.5
= 460-[460^2-2*120000000/(1*14.33*250)]^0.5 = 80mm
1.2.3 相对受压区高度 ξ = x / ho = 80/460 = 0.173 ≤ ξb = 0.518
1.2.4 纵向受拉钢筋 As = α1 * fc * b * x / fy = 1*14.33*250*80/360 = 793mm
1.2.5 配筋率 ρ = As / (b * ho) = 793/(250*460) = 0.69%
最小配筋率 ρmin = Max{0.20%, 0.45ft/fy} = Max{0.20%, 0.18%} = 0.20%
2.受剪构件:
(1)构造配筋
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度等级:C30 fc = 14.33N/mm ft = 1.43N/mm
1.1.3 箍筋抗拉强度设计值 fyv = 210N/mm 箍筋间距 s = 200mm
1.1.4 由剪力设计值 V 求箍筋面积 Asv,剪力设计值 V = 100kN
1.1.5 截面尺寸 b×h = 250×500mm ho = h - as = 500-40 = 460mm
1.2 计算结果
1.2.1 0.7 * ft * b * ho = 0.7*1.43*250*460 = 115348N ≥ V = 100000N
1.2.2 当 V ≤ 0.7 * ft * b * ho、 300 < H ≤ 500mm 构造要求:
箍筋最小直径 Dmin = 6mm,箍筋最大间距 Smax = 300mm
Dmin、Smax 的配箍面积 Asv# = Dmin ^ 2 * π / 4 * S / Smax = 19mm
最小配箍面积 Asv,min = 19mm
(2)计算配筋
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度等级:C30 fc = 14.33N/mm ft = 1.43N/mm
1.1.3 箍筋抗拉强度设计值 fyv = 210N/mm 箍筋间距 s = 200mm
1.1.4 由剪力设计值 V 求箍筋面积 Asv,剪力设计值 V = 200kN
1.1.5 截面尺寸 b×h = 250×500mm ho = h - as = 500-40 = 460mm
1.2 计算结果
1.2.1 0.7 * ft * b * ho = 0.7*1.43*250*460 = 115348N < V = 200000N
1.2.2 当 V > 0.7 * ft * b * ho、 300 < H ≤ 500mm 构造要求:
箍筋最小直径 Dmin = 6mm,箍筋最大间距 Smax = 200mm
最小配箍面积 Asv,min = (0.24 * ft / fyv) * b * S = (0.24*1.43/210)*250*200
= 82mm
1.2.3 矩形受弯构件,其受剪截面应符合下式条件:
当 ho / b ≤ 4 时,V ≤ 0.25 * βc * fc * b * ho (混凝土规范 7.5.1-1)
0.25 * βc * fc * b * ho = 0.25*1*14.33*250*460
= 412029N ≥ V = 200000N,满足要求。
1.2.4 矩形截面的一般受弯构件,其斜截面受剪承载力按下列公式计算:
V ≤ 0.7 * ft * b * ho + 1.25 * fyv * Asv / S * ho (混凝土规范 7.5.4-2)
Asv = (V - 0.7 * ft * b * ho) * S / (1.25 * Fyv * ho)
= (200000-0.7*1.43*250*460)*200/(1.25*210*460) = 140mm
3.弯剪扭构件:
(1)纯扭构件
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度:C30 fcu,k = 30N/mm fc = 14.33N/mm
ft = 1.43N/mm
1.1.3 钢筋强度:fy = 360N/mm fy' = 360N/mm fyv = 210N/mm
Es = 200000N/mm
1.1.4 弯矩设计值 M = 0kN·m 剪力设计值 V = 0kN 扭矩设计值 T = 80kN·m
箍筋间距 S = 200mm
1.1.5 矩形截面 截面尺寸 b×h = 350×600mm ho = 560mm
1.2 正截面受弯配筋计算
1.2.1 相对界限受压区高度 ξb = β1 / [1 + fy / (Es * εcu)]
= 0.8/[1+360/(200000*0.0033)] = 0.518
1.2.2 单筋矩形截面或翼缘位于受拉边的T形截面受弯构件受压区高度 x 按下式计算:
x = ho - [ho ^ 2 - 2 * M / (α1 * fc * b)] ^ 0.5
= 560-(560^2-2*0/1/14.33/350)^0.5 = 0mm ≤ ξb * ho = 0.518*560 = 290mm
1.2.3 As = α1 * fc * b * x / fy = 1*14.33*350*0/360 = 0mm
1.2.4 相对受压区高度 ξ = x / ho = 0/560 = 0 ≤ 0.518
配筋率 ρ = As / (b * ho) = 0/(350*560) = 0.00%
最小配筋率 ρmin = Max{0.20%, 0.45ft/fy} = Max{0.20%, 0.18%} = 0.20%
As,min = b * h * ρmin = 420mm
1.3 斜截面承载力计算
1.3.1 0.7 * ft * b * ho = 0.7*1.43*350*560 = 196593N ≥ V = 0N
当 V ≤ 0.7 * ft * b * ho、500 < H ≤ 800mm 构造要求:
箍筋最小直径 Dmin = 6mm,箍筋最大间距 Smax = 350mm
Dmin、Smax的配箍面积 Asv# = Dmin ^ 2 * π / 4 * S / Smax = 16mm
最小配箍面积 Asv,min = 16mm
1.3.2 一般受弯构件,其斜截面受剪承载力按下列公式计算:
V ≤ 0.7 * ft * b * ho + 1.25 * fyv * Asv/S * ho
0.7 * ft * b * ho = 0.7*1.43*350*560 = 196593N ≥ V = 0N,仅需按构造配箍
1.3.3 Asv,min = 16mm 箍筋最小直径 φ6 最大间距 @350
1.4 扭曲截面承载力计算
1.4.1 矩形截面受扭塑性抵抗矩
Wt = b ^ 2 * (3h - b) / 6 = 350^2*(3*600-350)/6 = 29604167mm
1.4.2 一般剪扭构件混凝土受扭承载力降低系数 βt 按下式计算:
βt = 1.5 / [1 + 0.5 * V * Wt / (T * b * ho)]
= 1.5/[1+0.5*0*29604167/(80000000*350*560)] = 1.5 > 1.0,取 βt = 1.0
1.4.3 验算截面适用条件
Hw / b = 560/350 = 1.6 < 6,截面高宽比满足要求
V / (b * ho) + T / (0.8 * Wt) = 0/(350*560)+80000000/(0.8*29604167)
= 3.38N/mm ≤ 0.25 * βc * fc = 3.58N/mm,
满足截面尺寸要求
V / (b * ho) + T / Wt = 0/(350*560)+80000000/29604167
= 2.70N/mm > 0.7 * ft = 1.00N/mm,需进行剪扭计算
1.4.4 验算是否要考虑剪力、扭矩的影响
当 V ≤ 0.35 * ft * b * ho 时,可仅按纯扭构件计算受扭承载力
0.35 * ft * b * ho = 0.35*1.43*350*560 = 98296N ≥ V = 0N,
可不考虑剪力的影响
当 T ≤ 0.175 * ft * Wt 时,可不进行受扭承载力计算
0.175 * ft * Wt = 0.175*1.43*29604167
= 7.423kN·m < T = 80.000kN·m,应进行受扭承载力计算
1.4.5 纯扭构件矩形截面腹板的受扭承载力应按下列公式计算:
T ≤ 0.35 * ft * Wt + 1.2 * ζ^0.5 * fyv * Ast1 * Acor / S
Acor = bcor * hcor = (350-2*30)*(600-2*30) = 156600mm
Ast1 = (T - 0.35 * ft * Wt) * S / (1.2ζ^0.5 * fyv * Acor)
= (80000000-0.35*1.43*29604167)*200/(1.2*1.2^0.5*210*156600) = 301mm
Ucor = 2 * (bcor + hcor) = 2*(290+540) = 1660mm
取 ζ = fy * Astl * S / (fyv * Ast1 * Ucor) = 1.2
受扭计算中取对称布置的全部纵向非预应力钢筋截面面积 Astl 可由下式求得:
Astl = fyv * Ast1 * Ucor * ζ / (fy * S) = 210*301*1660*1.2/(360*200)
= 1751mm
1.4.6 剪扭构件中箍筋和纵筋的最小配筋面积
箍筋最小配筋率 ρsv,min = 0.28 * ft / fyv = 0.19%
受扭纵筋最小配筋率 ρtl,min = 0.6 * [T / (V * b)] ^ 0.5 * ft / fy = 0.34%
腹板箍筋计算配筋面积 Asvt = Asv + 2 * Ast1 = 0+2*301 = 603mm
腹板箍筋最小配筋面积 Asvt,min = ρsv,min * b * S = 134mm
按受扭计算 Ast1 = 301mm,当箍筋间距为 200 时,箍筋最小直径 φ20
腹板受扭纵筋最小配筋面积 Astl,min = ρtl,min * b * h = 709mm
(2)剪扭构件:
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度:C30 fcu,k = 30N/mm fc = 14.33N/mm
ft = 1.43N/mm
1.1.3 钢筋强度:fy = 360N/mm fy' = 360N/mm fyv = 210N/mm
Es = 200000N/mm
1.1.4 弯矩设计值 M = 0kN·m 剪力设计值 V = 50kN 扭矩设计值 T = 30kN·m
箍筋间距 S = 200mm
1.1.5 矩形截面 截面尺寸 b×h = 250×500mm ho = 460mm
1.2 正截面受弯配筋计算
1.2.1 相对界限受压区高度 ξb = β1 / [1 + fy / (Es * εcu)]
= 0.8/[1+360/(200000*0.0033)] = 0.518
1.2.2 单筋矩形截面或翼缘位于受拉边的T形截面受弯构件受压区高度 x 按下式计算:
x = ho - [ho ^ 2 - 2 * M / (α1 * fc * b)] ^ 0.5
= 460-(460^2-2*0/1/14.33/250)^0.5 = 0mm ≤ ξb * ho = 0.518*460 = 238mm
1.2.3 As = α1 * fc * b * x / fy = 1*14.33*250*0/360 = 0mm
1.2.4 相对受压区高度 ξ = x / ho = 0/460 = 0 ≤ 0.518
配筋率 ρ = As / (b * ho) = 0/(250*460) = 0.00%
最小配筋率 ρmin = Max{0.20%, 0.45ft/fy} = Max{0.20%, 0.18%} = 0.20%
As,min = b * h * ρmin = 250mm
1.3 斜截面承载力计算
1.3.1 0.7 * ft * b * ho = 0.7*1.43*250*460 = 115348N ≥ V = 50000N
当 V ≤ 0.7 * ft * b * ho、300 < H ≤ 500mm 构造要求:
箍筋最小直径 Dmin = 6mm(规范10.2.11),箍筋最大间距 Smax = 300mm (规范表10.2.10)
Dmin、Smax的配箍面积 Asv# = Dmin ^ 2 * π / 4 * S / Smax = 19mm
最小配箍面积 Asv,min = 19mm
1.3.2 一般受弯构件,其斜截面受剪承载力按下列公式计算: (规范7.5.4)
V ≤ 0.7 * ft * b * ho + 1.25 * fyv * Asv/S * ho
0.7 * ft * b * ho = 0.7*1.43*250*460 = 115348N ≥ V = 50000N,仅需按构造配箍
1.3.3 Asv,min = 19mm 箍筋最小直径 φ6 最大间距 @300 (规范10.2.10、规范10.2.11)
1.4 扭曲截面承载力计算
1.4.1 矩形截面受扭塑性抵抗矩
Wt = b ^ 2 * (3h - b) / 6 = 250^2*(3*500-250)/6 = 13020833mm
1.4.2 一般剪扭构件混凝土受扭承载力降低系数 βt 按下式计算: (规范7.6.8)
βt = 1.5 / [1 + 0.5 * V * Wt / (T * b * ho)]
= 1.5/[1+0.5*50000*13020833/(30000000*250*460)]
= 1.37 > 1.0,取 βt = 1.0
1.4.3 验算截面适用条件 (规范7.6.1)
Hw / b = 460/250 = 1.84 < 6,截面高宽比满足要求
V / (b * ho) + T / (0.8 * Wt) = 50000/(250*460)+30000000/(0.8*13020833)
= 3.31N/mm ≤ 0.25 * βc * fc = 3.58N/mm,
满足截面尺寸要求
V / (b * ho) + T / Wt = 50000/(250*460)+30000000/13020833 (规范7.6.2)
= 2.74N/mm > 0.7 * ft = 1.00N/mm,需进行剪扭计算
1.4.4 验算是否要考虑剪力、扭矩的影响
当 V ≤ 0.35 * ft * b * ho 时,可仅按纯扭构件计算受扭承载力 (规范7.6.11)
0.35 * ft * b * ho = 0.35*1.43*250*460 = 57674N ≥ V = 50000N,
可不考虑剪力的影响
当 T ≤ 0.175 * ft * Wt 时,可不进行受扭承载力计算 (规范7.6.11)
0.175 * ft * Wt = 0.175*1.43*13020833
= 3.265kN·m < T = 30.000kN·m,应进行受扭承载力计算
1.4.5 纯扭构件矩形截面腹板的受扭承载力应按下列公式计算:
T ≤ 0.35 * ft * Wt + 1.2 * ζ^0.5 * fyv * Ast1 * Acor / S (规范式7.6.4-1)
Acor = bcor * hcor = (250-2*30)*(500-2*30) = 83600mm
Ast1 = (T - 0.35 * ft * Wt) * S / (1.2ζ^0.5 * fyv * Acor)
= (30000000-0.35*1.43*13020833)*200/(1.2*1.2^0.5*210*83600) = 203mm
Ucor = 2 * (bcor + hcor) = 2*(190+440) = 1260mm
取 ζ = fy * Astl * S / (fyv * Ast1 * Ucor) = 1.2
受扭计算中取对称布置的全部纵向非预应力钢筋截面面积 Astl 可由下式求得: (规范式7.6.4-2)
Astl = fyv * Ast1 * Ucor * ζ / (fy * S) = 210*203*1260*1.2/(360*200)
= 897mm
1.4.6 剪扭构件中箍筋和纵筋的最小配筋面积
箍筋最小配筋率 ρsv,min = 0.28 * ft / fyv = 0.19% (规范10.2.12)
受扭纵筋最小配筋率 ρtl,min = 0.6 * [T / (V * b)] ^ 0.5 * ft / fy = 0.34% (规范式10.2.5)
腹板箍筋计算配筋面积 Asvt = Asv + 2 * Ast1 = 0+2*203 = 407mm
腹板箍筋最小配筋面积 Asvt,min = ρsv,min * b * S = 96mm
按受扭计算 Ast1 = 203mm,当箍筋间距为 200 时,箍筋最小直径 φ18
腹板受扭纵筋最小配筋面积 Astl,min = ρtl,min * b * h = 422mm
(3)弯剪扭构件:
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 混凝土强度:C30 fcu,k = 30N/mm fc = 14.33N/mm
ft = 1.43N/mm
1.1.3 钢筋强度:fy = 360N/mm fy' = 360N/mm fyv = 210N/mm
Es = 200000N/mm
1.1.4 弯矩设计值 M = 240kN·m 剪力设计值 V = 180kN
扭矩设计值 T = 80kN·m 箍筋间距 S = 200mm
1.1.5 矩形截面 截面尺寸 b×h = 350×700mm ho = 660mm
1.2 正截面受弯配筋计算
1.2.1 相对界限受压区高度 ξb = β1 / [1 + fy / (Es * εcu)]
= 0.8/[1+360/(200000*0.0033)] = 0.518 (规范式7.1.4-1)
1.2.2 单筋矩形截面或翼缘位于受拉边的T形截面受弯构件受压区高度 x 按下式计算: (假定As’=0)
x = ho - [ho ^ 2 - 2 * M / (α1 * fc * b)] ^ 0.5 (规范式7.2.1-1)
= 660-(660^2-2*240000000/1/14.33/350)^0.5
= 77mm ≤ ξb * ho = 0.518*660 = 342mm
1.2.3 As = α1 * fc * b * x / fy = 1*14.33*350*77/360 = 1073mm (规范式7.2.1-2)
1.2.4 相对受压区高度 ξ = x / ho = 77/660 = 0.117 ≤ 0.518
配筋率 ρ = As / (b * ho) = 1073/(350*660) = 0.46%
最小配筋率 ρmin = Max{0.20%, 0.45ft/fy} = Max{0.20%, 0.18%} = 0.20% (规范表9.5.1一侧受拉钢筋)
As,min = b * h * ρmin = 490mm
1.3 斜截面承载力计算
1.3.1 0.7 * ft * b * ho = 0.7*1.43*350*660 = 231698N ≥ V = 180000N (规范式7.5.7-1)
当 V ≤ 0.7 * ft * b * ho、500 < H ≤ 800mm 构造要求: (规范表10.2.10)
箍筋最小直径 Dmin = 6mm,箍筋最大间距 Smax = 350mm
Dmin、Smax的配箍面积 Asv# = Dmin ^ 2 * π / 4 * S / Smax = 16mm (?)
最小配箍面积 Asv,min = 16mm
1.3.2 一般受弯构件,其斜截面受剪承载力按下列公式计算: (规范式7.5.4-2)
V ≤ 0.7 * ft * b * ho + 1.25 * fyv * Asv/S * ho
0.7 * ft * b * ho = 0.7*1.43*350*660
= 231698N ≥ V = 180000N,仅需按构造配箍
1.3.3 Asv,min = 16mm 箍筋最小直径 φ6 最大间距 @350
1.4 扭曲截面承载力计算
1.4.1 矩形截面受扭塑性抵抗矩
Wt = b ^ 2 * (3h - b) / 6 = 350^2*(3*700-350)/6 = 35729167mm (规范式7.6.3)
1.4.2 一般剪扭构件混凝土受扭承载力降低系数 βt 按下式计算: (规范式7.6.8-2)
βt = 1.5 / [1 + 0.5 * V * Wt / (T * b * ho)]
= 1.5/[1+0.5*180000*35729167/(80000000*350*660)]
= 1.28 > 1.0,取 βt = 1.0
1.4.3 验算截面适用条件
Hw / b = 660/350 = 1.89 < 6,截面高宽比满足要求 (规范式7.6.1-1)
V / (b * ho) + T / (0.8 * Wt) = 180000/(350*660)+80000000/(0.8*35729167)
= 3.58N/mm ≤ 0.25 * βc * fc = 3.58N/mm,
满足截面尺寸要求
V / (b * ho) + T / Wt = 180000/(350*660)+80000000/35729167
= 3.02N/mm > 0.7 * ft = 1.00N/mm,需进行剪扭计算 (规范式7.6.2-1)
1.4.4 验算是否要考虑剪力、扭矩的影响
当 V ≤ 0.35 * ft * b * ho 时,可仅按纯扭构件计算受扭承载力 (规范7.6.11)
0.35 * ft * b * ho = 0.35*1.43*350*660 = 115849N < V = 180000N,
应考虑剪力的影响
当 T ≤ 0.175 * ft * Wt 时,可不进行受扭承载力计算 (规范7.6.11)
0.175 * ft * Wt = 0.175*1.43*35729167
= 8.959kN·m < T = 80.000kN·m,应进行受扭承载力计算
1.4.5 在剪力和扭矩共同作用下矩形截面一般剪扭构件,其腹板受剪扭承载力应按下列公式计算:
1.4.5.1 剪扭构件的受剪承载力:
V ≤ (1.5 - βt) * 0.7 * ft * b * ho + 1.25 * fyv * Asv/S * ho (规范式7.6.8-1)
Asv = [V - (1.5 - βt) * 0.7 * ft * b * ho] * S / (1.25 * fyv * ho)
= [180000-(1.5-1)*0.7*1.43*350*660]*200/(1.25*210*660) = 74mm
1.4.5.2 剪扭构件的受扭承载力:
T ≤ βt * 0.35 * ft * Wt + 1.2 * ζ^0.5 * fyv * Ast1 * Acor / S (规范式7.6.4-1)
Acor = bcor * hcor = (350-2*30)*(700-2*30) = 185600mm
受扭计算中沿截面周边配置的箍筋单肢截面面积 Ast1 由下式求得:
Ast1 = (T - βt * 0.35 * ft * Wt) * S / (1.2ζ^0.5 * fyv * Acor)
= (80000000-1*0.35*1.43*35729167)*200/(1.2*1.2^0.5*210*185600) = 242mm
Ucor = 2 * (bcor + hcor) = 2*(290+640) = 1860mm
取 ζ = fy * Astl * S / (fyv * Ast1 * Ucor) = 1.2
受扭计算中取对称布置的全部纵向非预应力钢筋截面面积 Astl 可由下式求得: (规范式7.6.4-2)
Astl = fyv * Ast1 * Ucor * ζ / (fy * S) = 210*242*1860*1.2/(360*200)
= 1578mm
1.4.6 剪扭构件中箍筋和纵筋的最小配筋面积
箍筋最小配筋率 ρsv,min = 0.28 * ft / fyv = 0.19% (规范10.2.12)
受扭纵筋最小配筋率 ρtl,min = 0.6 * [T / (V * b)] ^ 0.5 * ft / fy = 0.27% (规范式10.2.5)
腹板箍筋计算配筋面积 Asvt = Asv + 2 * Ast1 = 74+2*242 = 559mm (规范7.6.12)
腹板箍筋最小配筋面积 Asvt,min = ρsv,min * b * S = 134mm
按受扭计算 Ast1 = 242mm,当箍筋间距为 200 时,箍筋最小直径 φ18 (?)
腹板受扭纵筋最小配筋面积 Astl,min = ρtl,min * b * h = 659mm
4.双向板构件:
1.1 基本资料
1.1.1 工程名称:工程一
1.1.2 边界条件(左端/下端/右端/上端): 固端 / 固端 / 固端 / 固端
1.1.3 荷载标准值(按静力计算手册考虑活荷不利布置)
1.1.3.1 永久荷载标准值
楼板自重: gk1 = 4.5kN/m
1.1.3.2 可变荷载标准值
均布荷载: qk1 = 2.5kN/m γQ = 1.4 ψc = 0.7 ψq = 0.4
1.1.4 计算跨度 Lx = 3600mm 计算跨度 Ly = 4800mm
板厚 h = 120mm (h = Lx / 30)
板底、板面纵筋合力点至近边距离:as = 20mm、as' = 20mm
1.1.5 混凝土强度等级:C30 fc = 14.33N/mm ft = 1.43N/mm
ftk = 2.01N/mm Ec = 29791N/mm
1.1.6 钢筋抗拉强度设计值 fy = 360N/mm Es = 210000N/mm
1.2 弯矩计算结果
1.2.1 平行于 Lx 方向的跨中弯矩 Mx
Mxgk1 = (0.0296+0.2*0.013)*4.5*3.6^2 = 1.88kN·m
Mxqk1 = [(0.0296+0.2*0.013)*2.5*3.6^2+(0.062+0.2*0.0317)*2.5*3.6^2]/2
= 1.63kN·m
Mx = Max{Mx(L), Mx(D)} = Max{4.53, 4.13} = 4.53kN·m
Mxk = 3.51kN·m Mxq = 2.53kN·m
Asx = 128mm ρ = 0.13% ρmin = 0.20% Asx* = 240mm
12@200 (As = 565) ωmax = 0.020mm
1.2.2 平行于 Ly 方向的跨中弯矩 My
Mygk1 = (0.013+0.2*0.0296)*4.5*3.6^2 = 1.10kN·m
Myqk1 = [(0.013+0.2*0.0296)*2.5*3.6^2+(0.0317+0.2*0.062)*2.5*3.6^2]/2
= 1.02kN·m
My = Max{My(L), My(D)} = Max{2.75, 2.49} = 2.75kN·m
Myk = 2.12kN·m Myq = 1.51kN·m
Asy = 86mm ρ = 0.10% ρmin = 0.20% Asy* = 2
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