结构倒塌时楼板碰撞效应的简化评估方法  

A SIMPLIFIED EVALUATING METHOD FOR IMPACTING OF FLOOR SLABS DURING STRUCTURAL COLLAPSE

作　　者：吴波[1] 黄仕香[1,2] 

机构地区：[1]华南理工大学亚热带建筑科学国家重点实验室,广东广州510640 [2]重庆大学土木工程学院,重庆400045

出　　处：《工程力学》2013年第3期306-314,共9页Engineering Mechanics

基　　金：国家自然科学基金重大研究计划培育项目(90815012);国家杰出青年科学基金项目(51025829);亚热带建筑科学国家重点实验室重点研究项目(2009ZA04);重庆大学接收研究生国内访学项目(F-0920)

摘　　要：针对上楼板、下楼板碰撞的两种极限状态——完全塑性碰撞和完全刚性碰撞，开展了碰撞过程中动能转移量的理论分析，考察了上板、下板质量比对动能转移量的影响，同时进行了2种极限状态下动能转移量的数值计算；提出了结构倒塌时上板、下板碰撞效应的一种简化评估方法，具体包括2个步骤：1）下板的非线性静力分析：2）采用能量平衡原理估算上板的最大允许重力荷载。研究表明：上板、下板质量比等于1时，完全塑性碰撞后的总动能转移百分比和下板动能转移百分比分别为33.3％和16．7％；完全刚性碰撞后的下板动能转移百分比与碰撞前上板速度、碰撞后上板周边反弹速度等参数有关，上板、下板质量比等于1时下板动能转移百分比为44．4％～97．1％；采用通用软件ABAQUS计算得到的两种极限状态对应的下板动能转移白分比，总体上与理论分析结果较为接近。Kinetic energy transfer from an above failed floor slab to an impacted floor slab is theoretically analyzed for two extreme impact possibilities, namely fully plastic impact and fully rigid impact, and the influence of a ratio of the failed slab＇s mass to the impacted slab＇s mass on the kinetic energy transfer is discussed Numerical simulations are also conducted for the kinetic energy transfer related to the two extreme impact possibilities. Then, a simplified evaluating method is proposed to assess the impacting effect between the failed and impacted slabs, including two stages： l） nonlinear static analysis of the impacted floor slab, and 2） determination of the maximum acceptable gravity load of the failed floor slab using a simplified energy balance approach. It can be seen that： 1） in the case that the failed slab＇s mass is equal to the impacted slab＇s mass, the total kinetic energy transfer percentage and the impacted slab＇s kinetic energy transfer percentage related to fully plastic impact are, respectively, 33.3% and 16.7%; 2） the impacted slab＇s kinetic energy transfer percentage related to fully rigid impact is affected by velocity of the failed slab before impacting and edge velocity of the failed slab after impacting. In the case that the failed slab＇s mass is equal to the impacted slab＇s mass, the impacted slab＇s kinetic energy transfer percentage related to fully plastic impact is range from 44.4% to 97.1%; and 3） the calculated impacted slab＇s kinetic energy transfer percentages related to the two extreme impact possibilities using ABAQUS are close to the theoretically analyzing results on the whole.

关 键 词：结构倒塌 楼板碰撞 简化评估方法 能量转移 连续倒塌 

分 类 号：TU311[建筑科学—结构工程]