【摘要】 结构在大震作用下会进入弹塑性并产生损伤,准确预测地震荷载下结构的非线性行为,对评估结构的抗震安全性具有重要意义。总结了现有的一些结构弹塑性分析模型,并介绍了清华大学土木工程系近年来以通用有限元程序MSC.MARC为平台所开发的一些新的结构弹塑性分析模型。这些模型可以直接将构件的非线性节点力(轴力、剪力和弯矩)、节点变形(平动和转动)和材料的非线性应力—应变行为联系起来,可以模拟各种复杂受力构件的滞回行为和轴力—双向弯曲—剪切耦合行为。同时,借助通用有限元程序方便的前后处理功能和非线性计算功能,这些模型可以准确模拟地震作用下结构的三维非线性地震响应。利用这些工具,对一个实际工程结构进行了静力弹塑性分析和动力弹塑性时程分析,表明这些分析模型可以较好地模拟实际工程结构中的各种弹塑性行为,供科研和工程人员参考。更多还原

【Abstract】 Structures will enter nonlinear stage during strong earthquakes.Hence accurate prediction for the structural nonlinear behaviors is important to the safety and loss assessment during earthquakes.This paper reviews the existed nonlinear analytic models for structures and presents some novel models for structural nonlinear analysis that recently developed by the Tsinghua university.With these models,the material stress-strain relationship can be connected directly with the force-displacement behavior of the structural elements.So that the complicated coupled axial force-bending moment-shear force behaviors can be properly simulated,as well as the corresponding cycle behaviors.With the secondary development user subroutines,convenient pre and post process functions and extinct nonlinear capacity of general purpose FE software of MSC.MARC,the spatial seismic responds of structures can be precisely simulated.A steel frame-core wall structure with an eccentric tube is analyzed with static pushover and dynamic time-history analysis to demonstrate the applications of the new models.更多还原