M1(0.0268+0.2*0.0159)*6.36*3.62+(0.0456+0.2*0.0358)*1.3*3.62=3.36 (0.0387+0.2*0.045)*6.36*2.32+(0.0892+0.2*0.0210)*1.3*2.32=2.24 (0.0291+0.2*0.0224)*6.36*3.72+(0.0456+0.2*0.0358)*1.3*3.72=3.86 M2(0.01
M1 (0.0268+0.2*0.0159)*6.36*3.62+(0.0456+0.2*0.0358)*1.3*3.62=3.36
(0.0387+0.2*0.045)*6.36*2.32+(0.0892+0.2*0.0210)*1.3*2.32=2.24
(0.0291+0.2*0.0224)*6.36*3.72+(0.0456+0.2*0.0358)*1.3*3.72=3.86
M2 (0.0159+0.2*0.0268)*6.36*2.32+(0.0358+0.2*0.0456)*1.3*2.32=1.02
(0.045+0.2*0.0387)*6.36*2.32+(0.0210+0.2*0.0892)*1.3*2.32=2.04
(0.0224+0.2*0.0291)*6.36*3.72+(0.0358+0.2*0.045)*1.3*3.72=3.26
屋面E块板(120mm板厚):
q=1.3*2.0=2.6KN/㎡,g=1.2*4.22=5.06KN/㎡,g+q/2=5.06+2.6/2=6.36KN/㎡
q/2=1.3KN/㎡,g+q=5.06+2.6=7.66KN/㎡
E板属于內跨故l_0=l_c L01=2.3m L02=3.1m。
跨中最大弯矩为内支固定时,在g+q/2作用下的跨中弯矩值与内支座铰接时在q/2作用下的跨中弯矩值之和,μ取0.2,支座最大负弯矩为当内支座固定时g+q作用下的支座弯矩。
M1=(0.0302+0.2*0.0126)×6.36*2.32+(0.0631+0.2*0.0307)*1.3*2.32=1.58
M2=(0.0126+0.0302*0.2)*6.36*2.32+(0.0307+0.2*0.0631)*1.3*2.32=0.927
M1'=-0.0708*7.66*2.32=-2.87
M2'=-0.0565*7.66*2.32=-2.29
一类环境中的最小混凝土保护层厚度为15mm,假定选用HRB400直径为10的钢筋,则
LO1方向跨中截面的ho1=120-15=105mm
LO2方向跨中截面的ho2=105-10=95mm
支座截面的h_0=80mm。
截面设计用的弯矩:因楼该周边有梁与板整浇,故所有去个的跨中弯矩及A-A支座弯矩减少20%,配筋如下:
E区格X方向:
α_s = M/(α_1 f_c bh_0 ) = 1.58*106/1.0*14.3*1000*1052=0.01
ξ =1-√ (1-2*αs) = 1-√(1-2*0.01) = 0.01<0.55
Ys= 0.5*(1+√ (1-2*αs) )= 0.995
As = α1*fc*b*ho*ξ/fy = 1.000*14.3*1000*105*0.01/360
= 41.7mm2
5) 验算最小配筋率
ρ = As/(b*h) = 41.7/(1000*100) = 0.042%
ρ<ρmin = 0.200% 不满足最小配筋要求
所以取面积为As = ρmin*b*h = 0.200%*1000*100 = 200 mm2
采取方案8@200, 实配面积251 mm2
E区格Y方向:
α_s = M/(α_1 f_c bh_0 ) =0.927*106/1.0*14.3*1000*952=0.007
ξ =1-√ (1-2*αs) = 1-√(1-2*0.007) = 0.01=0.007<0.55
Ys= 0.5*(1+√ (1-2*αs) )= 0.997
As = α1*fc*b*ho*ξ/fy = 1.000*14.3*1000*95*0.007/360
=26mm2
5) 验算最小配筋率
ρ = As/(b*h) = 26/(1000*100) =0.026%
ρ<ρmin = 0.200% 不满足最小配筋要求
所以取面积为As = ρmin*b*h = 0.200%*1000*100 = 200 mm2
采取方案8@200, 实配面积251 mm2
F
G
H
Lo1(m)
3.6
2.3
3.7
Lo2(m)
4.0
4.1
4.1
Lo21/Lo2
0.90
0.56
0.90
M1 (0.0268+0.2*0.0159)*6.36*3.62+(0.0456+0.2*0.0358)*1.3*3.62=3.36
(0.0387+0.2*0.045)*6.36*2.32+(0.0892+0.2*0.0210)*1.3*2.32=2.24
(0.0291+0.2*0.0224)*6.36*3.72+(0.0456+0.2*0.0358)*1.3*3.72=3.86
M2 (0.0159+0.2*0.0268)*6.36*2.32+(0.0358+0.2*0.0456)*1.3*2.32=1.02
(0.045+0.2*0.0387)*6.36*2.32+(0.0210+0.2*0.0892)*1.3*2.32=2.04
(0.0224+0.2*0.0291)*6.36*3.72+(0.0358+0.2*0.045)*1.3*3.72=3.26
M1´' -0.0663*7.66*3.62=-6.58 -0.0824*7.66*2.32=-3.34 -0.0776*7.66*3.72=-8.14
M2' -0.0563*7.66*3.62=-5.59