(提示:T1?2?T?Giui2,?T?0.6)(2009-10第40题、5章P257) ?Giui
40.(1)各层层间侧移刚度
?Di?1.2?104?2?2.4?104?2?7.2?104kNm (1分)
n(2)各层层间剪力 Vi??Gi
i?1则:V6?1440kN;V5?2880kN;V4?4320kN
V3?5760kN;V2?7200kN;V1?8640kN (1分)
(3)各层层间侧移
?ui?Vi D?i则:?u1?0.12m;?u2?0.10m;?u3?0.08m
?u4?0.06m;?u5?0.04m;?u6?0.02m (1分)
(4)各层质点i处的侧移
ui???ui
i?1n则:u1?0.12m;u2?0.22m;u3?0.30m
u4?0.36m;u5?0.40m;u6?0.42m (1分)
(5)自振周期
T1?2?T?Giui2?Giui1440?0.122?0.222?0.302?0.362?0.402?0.422?2?0.6?1440??0.12?0.22?0.30?0.36?0.40?0.42??2?0.6?0.5831?0.700s???2分?
6.如题37图所示框架结构的重力荷载代表值G1=G2=……=G5=1500kN,各层边柱D值均为1.5×104kN/m,各层中柱D值均为2.0×104kN/m。试按顶点位移法计算其自振周期。(提示:T1=1.7?TuT,?T?0.6)(2011-01第37题、5章P257)
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题37图
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