地震作用下基于响应敏感性的单层球面网壳冗余度分析方法研究

冗余特性是结构鲁棒性的重要组成部分,也是损伤情况下结构安全性的体现。在地震等动力荷载作用下单层球面网壳结构的倒塌模式由诸多因素决定,其中结构的冗余度是重要的影响因素。为合理评估地震作用下的结构冗余度,本文基于结构响应对单元材料弹性模量的敏感性提出地震作用下的结构构件冗余度评价方法,并对一星型网壳在地震作用下的弹性、弹塑性冗余度进行分析,以验证方法的有效性。结果表明,结构冗余度能够反映构件在结构中的重要性,冗余度值的大小是构件重要性的衡量指标,低冗余度构件是结构的关键构件。利用结构的冗余度分布,可以采取加强低冗余构件的措施,从而实现网壳结构倒塌模式的优化控制。

Redundancy of single-layer reticulated dome under earthquake action based on response sensitivity

Redundancy is an important part of structural robustness.It reflects the security of structure under damage.The earthquake collapse mechanism of single-layer reticulated dome is determinated by several factors,and the structural redundancy is an important aspect.In this paper,a method is proposed based on the response sensitivity to assess the redundancy of structure under earthquake action,in which the derivation of element strain to elastic modulus of structural materials is taken as the response sensitivity.The elastic redundancy and elastic-plastic redundancy of a 24-member dome under earthquake action are analyzed,and the effectiveness of the proposed method is verified.Results show that the redundancy is an index for the importance of structural component.Structural elements with small redundancies are the key components of the structure.It is believed that some measures can be taken to improve the structural redundancy for the optimal control of the collapse of the reticulated dome.