爆炸作用下刚塑性简支梁的塑性动力响应分析

Analysis of the plastic dynamic response to a rigid-plastic simply supported beam subjected to explosive loading

为了研究梁板类构件在爆炸荷载作用下的塑性动力响应,将爆炸荷载简化为双指数型荷载,按均布荷载施加到刚塑性简支钢梁上.根据不同时刻,将梁的运动分为4种运动模式,分析了梁的最大变形和时间的关系.当出现移行铰后,根据移行铰的特性,分析了此后梁各个阶段的运动,并给出塑性铰的位置与梁的运动规律之间的关系,从而得出梁在各个时刻的挠度、速度以及转角等参量随时间变化的公式,并最终得到简支梁在爆炸荷载作用下的最大残余挠度公式.最后将理论计算结果和数值模拟结果进行对比,两者所得结果基本吻合.

In order to study the plastic dynamic response of a beam-slab structure subjected to the explosive load- ing, the blast load was simplified to double exponential loading and uniformly applied to the rigid-plastic simply supported steel beam. Then the movement of the beam at different moments was divided into four exercise modes and the relation between the largest deformation and time was studied. After the moving plastic hinge appeared, the beam movement of every stage after that was analyzed based on the characteristics of the moving plastic hinge, and the relation between the location of the plastic hinge and the motion law of the steel beam was obtained. Thus the formulas of the parameters of the beam including deflection, velocity, angle of rotation, etc., changing with time were obtained and eventually, the maximum residual deflection of the simply supported steel beam subjected to the explosive loading was obtained. Finally, the theoretical calculation results and the numerical simulation results were compared through an example and the two results were found to be basically in agreement.