瞬时冲击荷载作用RC构件直剪破坏模式分析  

Investigation on the failure mode of RC members subjected to impulsive loading

作　　者：葛楠[1] 苏幼坡[1] 王兴国[1] 

机构地区：[1]河北联合大学建筑工程学院,河北唐山063009

出　　处：《西安建筑科技大学学报（自然科学版）》2010年第6期809-814,共6页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50778061)

摘　　要：根据拉格朗日第二类方程,得出了结构构件在瞬时冲击荷载作用下直剪型动力反应计算公式,分析过程与冲击荷载的峰值、持时以及系统约束反力的不确定性无关,而只与冲量值大小有关.结果表明,无论是在集中冲击荷载还是在分布冲击荷载的作用下,当荷载持时趋近无限小时,在构件早期的动力反应中支座边缘处的位移存在不连续性,从而在理论上证明了结构发生直剪型破坏的可能性是存在的;进而也可以认为,冲击荷载持时越短,峰值越大,发生直剪破坏的可能性越大.The dynamic response of structure member subjected to impulsive load was derived from the second class of Lagrange＇s Equation.The process was completely free of the dilemma resulted from uncertainty of peak value,time interval,time history of impulsive load and constraint reaction.It was only related with load impulse.The results show that when the time interval of impulsive load,either concentrated or distributed,become infinitesimal,there will be the discontinuity in the distribution of transverse displacement at the earliest stage of dynamic response near the supports.The solution acceptably explained the possibility of direct shear failure under impulsive load.It is also believed that a shorter time interval and larger peak value of impulsive load tends to correspond to a larger potentiality of direct shear failure.

关 键 词：冲击荷载 破坏模式 直剪 富氏级数 拉格朗日方程 

分 类 号：TU411.3[建筑科学—岩土工程] TU311.3[建筑科学—土工工程]