连续倒塌动力效应对极限承载力影响的数值分析  

Numerical Analysis of the Influence of Dynamic Effect in Progressive Collapse on Ultimate Bearing Capacity

作　　者：王磊[1] 陈以一[1,2] 

机构地区：[1]同济大学建筑工程系,上海200092 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《结构工程师》2009年第4期30-34,共5页Structural Engineers

基　　金：高等学校博士学科点专项科研基金(20060247034)

摘　　要：对连续性破坏进程中由于初始局部破坏产生的动力效应对结构体系极限承载力的影响进行了数值研究。以低冗余度的平面桁梁体系为研究对象,以变形作为破坏准则,通过使用有限元软件ABAQUS中的显式和隐式积分程序分别分析了考虑和不考虑连续破坏进程中动力效应对极限承载力的影响。算例分析结果表明,当初始局部破坏部位选为中间的竖杆,且上、下弦杆的长细比在40~150变化时,考虑动力效应是不考虑动力效应极限承载力的92%~80%,显然动力效应对低冗余度结构体系有较大的影响。使用显式积分算法深入研究了初始局部破坏产生的动力效应对极限承载力影响的具体程度,为今后的连续性破坏机理研究提供了有效的方法。Numerical study of the influence of dynamic effect in progressive collapse on ultimate bearing capacity due to incipient local failure was carried out. Taking planar truss-beam structural system with low redundancy as the object of study and deformation as failure criteria, the influence of dynamic effect during progressive collapse was analyzed by using EXPLICIT and IMPLICIT integration program of FEM software ABAQUS respectively. The results show that when the middle vertical bar is regarded as incipient local failure position and the slenderness ratio of upper and low chords varies from 40 to 150, the ultimate bearing capacity considering dynamic effect shall be reduced into 92% -80% in a noticeable level. The results show also the numerical program is an effective method for the future study of failure mechanism of progressive collapse.

关 键 词：连续倒塌 动力效应 显式积分 极限承载力 初始破坏 

分 类 号：TU312[建筑科学—结构工程]