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1、五活荷载内力计算(屋面布雪荷载)(一)活荷载计算1 .屋面框架梁线荷载标准值q5AB=0.653.9=2.54kNmq5Bc=O.653.O=1.95kNm2 .楼面框架梁线荷载标准值qAB=2.03.9=7.8kNmqBc=2.53.0=7.5kNm3 .屋面框架节点集中荷载标准值边节点:纵向框架梁传来的雪荷载3.920.652=4.94kN次梁传来的雪荷载(12x0.272+0.273)x0.65x3.9x7.22=7.98kN贝IJQ5A=12.92kN中节点:纵向框架梁传来的雪荷载4.94+(1-20.192+0.193)0.657.832=12.05kN则Q5B=12.05+7.98
2、=20.03kN4 .楼面框架节点集中荷载标准值边节点:纵向框架梁传来的活荷载3.922.02=15.21kN次梁传来的活荷载(1-2x0.272+0.273)x2.0x3.9x7.22=24.54kN则Qa=39.75RN中节点:纵向框架梁传来的雪荷载15.21+(1-20.192+0.193)2.07.832=42.55kN贝IJQ5B=42.55+24.54=67.09kN(二)活荷载作用下内力计算1 .计算简图见下页2 .荷载等效计算简图顶层边跨q5ia=(1-20.272+0.273)2.54=2.22kN/m顶层中跨q,5=-1.95=1.22kNm8中间层边跨*边=(1-20.2
3、72+0.273)7.8=6.82kN/m中间层中跨q,5=-7.5=4.69kN/m8荷载等效后的计算简图如下:3 .固端弯矩计算顶层边跨M5ab=2.227.22=9.59kNm*D2顶层中跨M5bc=1.221.52=0.92kNm中间层边跨Mab=6.827.22=29.46kNma12中间层中跨M5bc=4.69x1.52=3.52kNm4 .分层计算弯矩1)顶层内力计算过程如下(单位:kNm)1-41-20.4310.5692-10.4422-50.3352-30.223-9.599.59-0.924.135.462.73-2.52-5.04-3.82-2.541.091.430.
4、72-0.32-0.24-0.165.22-5.227.68-4.06-3.62M图如下(单位:kNm)2)中间层内力计算过程见下页(单位:kNm)3-60.3013-10.3013-40.3984-30.3314-20.2514-70.2514-50.167-29.4629.46-3.528.878.8711.725.86-5.27-10.53-7.98-7.98-5.311.581.582.111.06-0.35-0.27-0.27-0.1710.4510.45-20.9025.5-8.25-8.25-9M图如下(单位:kNm)3)底层内力计算过程如下(单位:kNm)3-63-13-44-
5、34-24-74-50.320.3070.3730.3280.2480.2590.165-29.4629.46-3.529.439.0410.995.50-5.160.97-0.32-0.24-0.25-0.1611.0810.62-21.7025.3-8.04-8.39-8.87M图如下(单位:kNm)56 .不平衡弯矩分配计算过程如下(单位:kNm),方框内为原不平衡弯矩左梁上柱Ttt1.221.983.48-1.980.17-1.83-2.750.61-0.321.361.74-1.351.913.48-2.08-1.72-2.750.683.481.391.S2-2.75-1.371.
6、393.48-2.78-1.37-2.750.923.481.37I.S0-2.75-1.391.433.54-2.8-1.32-2.680.913.482.410.90-2.75-2.07-1.11-1.300.710.46不平衡弯矩调整之后即可得出活荷载作用下框架弯矩图,如下(单位:kNm,括号内为调幅后的弯矩值)M图(单位:kNm)7 .跨中弯矩计算.ICCCT7.50+8.90NIC1ZM5b=-2.227.2=6.19kNm82Msbc=1.953.02-3.01=-1.55kNm5bc12M4b=-6.827.22-822.98+26.86=49.19-24.92=19.27kNm
7、M4bc.=7.53.02-8.32=5.63-8.32=-2.69kNmbc12M3ab=44.19-23.68+27.32=j8.69kN.mM3bc=5.63-8.08=-2.45kNmM.b=44.19-=18.69kNm2.fo2M2bc=5.63-8.09=-2,46kNmRIi.ir,23+26.2Mib=44.19=19.59kNmMibc=5.63-8.41=-2.78kNm因为楼面活载是按满布计算的,故跨中弯矩应乘以1.1进行放大。8 .剪力计算顶层中跨端部剪力V$bc=1.95=1.46kN其他层中跨段部剪力VBC=7.5y=5.63kN各边跨段部剪力:V5b=7,58,
8、9+2.54(7.2-)-=6.47kN39V5b=2.54(7.2-)-6.47=6.87kN,j22.98-26.86_o_3.9,1z_.1.r_ICCZMNTV4b=F7.8(7.2)0.544X40.9519.94kN4b7.2222V4ba=40.95-19.94=21.01kN23.68-27.321V3b=+-40.95=19.97kN3AB7.22V3ba=40.95-19.97kNOQ77731V2ab=3+40.95=19.98kNV2ba=40.95-19.98=20.97kNVib=232+140.95=20.04kNViba=40.95-20.04=20.91kN8
9、.轴力计算N5a=12.92+6.47=19.39kNN4a=19.39+39.75+19.94=79.08kNN3a=79.0839.75+19.97=138.80kNN2a=138.80+39.75+19.98=198.53kNNia=198.53+39.75+20.04=258.32kNN5b=20.03+1.466.87=28.36kNN4b=28.36+5.63+67.09+21.01=122,09kNN,B=122.09+72.72+20.98=215.79kNN2b=215.79+72.72+20.97=309.48kNNib=309.48+72.72+20.91=403.I1kN框架结构的剪力图和轴力图如下:(单位:kN)V,N图(单位:kN)9 .弯矩调幅边跨:端部弯矩值乘以0.85,跨中弯矩值乘以1.2中跨:端部弯矩值乘以0.85,跨中弯矩值乘以0.9将调幅后的弯矩值表于框架弯矩图的O内10 .梁端柱边剪力与弯矩V(kN)M(kNm)6.41-6.811.41-4.465.53-2.1419.76-20.835.41-13.6016.58-5.4519.79-20.85.41-14.1916.98-5.2519.80-20.795.41-14.2116.97-5.2619.83-20.75.37-13.1115.54-5.40