第五章横向风荷载计算5.1自然情况基本风压为0.40kN/m2,即W0=0.40kN/m2,c类粗糙度。5.2荷载计算:1.风荷载标准值Wk=βzμsμzWoAwFkiwkiβz-高度z处的风振系数2.风压高度变化系数(μz):μ5=0.84μ4=μ3=μ2=μ1=0.743.风荷载体型系数:μs=1.44.Z高度处的风振系数在实际工程中,对于高度不大于30m,高宽比小于1.5的高层建筑,取风振系数βZ=1.0层数βZμSμZiW0WkiFWkiVi51.01.40.840.400.475.635.6340.740.416.6412.2730.740.416.6418.9120.740.416.6425.5510.740.417.4132.965.Fwk5=0.47×(0.8+1.8)×4.5=5.63kNFwk4=0.41×3.6×4.5=6.642kNFwk3=0.41×3.6×4.5=6.642kNFwk2=0.41×3.6×4.5=6.642knFwk1=0.41×(1.8+2.215)×4.5=7.41kN6.层间剪力V5=5.63kNV4=12.276kNV3=18.91kNV2=25.55kNV1=32.96kN7.荷载作用分布图:5.6312.27F4F5360036003600V4V53600Fn32.9618.9125.55V3F3V14430F1F2V25.3风荷载作用下框架柱剪力和柱弯矩(D值法,取横向中框架计算)1.柱剪力Vik=D/ΣD×Vi,柱弯矩M下=Vik×Yi,M上=Vik×(1-Yi)×hi2.反弯点高度h’=(y0+y1+y2+y3)×hy0——标准反弯点高度比y1——为上、下层梁线刚度变化修正值y2——为上层层高变化修正值y3——为下层层高修正值根据框架总层数m,该柱所在层数n和梁柱线刚度比值K确定,对于地震作用,y值由按荷载表查得,并由内插法根据K值确定,并考虑层高的因素进行修正。3.边柱弯矩计算:层HΣDDD/ΣDViVikkYM下M上53.6118332233330.1975.631.1090.790.301.1982.79543.6118332233330.19712.272.4170.790.403.4805.22133.6118332233330.19718.913.7250.790.456.0357.38623.6118332233330.19725.555.0330.790.509.0599.05914.4398388219140.22332.967.3500.970.6521.16411.3964.中柱弯矩计算:层HΣDDD/ΣDViVikkYM下M上53.6118332233330.3035.631.7061.490.382.3033.83943.6118332233330.30312.273.7181.490.435.6897.69633.6118332233330.30318.915.7301.490.489.79810.83023.6118332233330.30325.557.7421.490.513.93613.93614.4398388219140.27732.969.1301.840.5722.89217.554计算过程(1)iikVDDV(2)yhVMik下;(3)hyVMik)1(上5.4荷载作用下梁端弯矩计算根据节点平衡由柱端弯矩求得梁轴线处弯矩下(上柱)上(下柱)右(左梁)左(右梁)ΣMc=M右+M左=M上+M下2111KKK;2122KKKM右(左梁)=μ1McM左(右梁)=μ2Mc求得边跨μ1=1μ2=1中跨μ1=0.531μ2=0.469风荷载作用下框架梁端剪力和柱轴力标准植楼层AB跨梁端剪力BC跨梁端剪力柱轴力LM左M右VELM左M右VE边柱中柱57.22.7952.0390.6712.71.8001.8001.3330.6710.66247.26.7195.3091.6712.74.6904.6903.4742.3422.46537.210.8568.7722.7262.77.7477.7475.7395.0685.47827.215.09412.6033.8472.711.13111.1318.2458.9159.87617.220.45516.7215.1632.714.76914.76910.9414.07815.653风荷载作用下的框架内力图如下: