非规则梁桥的模态推倒分析  

Modal pushover analysis of an irregular continuous bridge

作　　者：魏标[1] 李建中[2] 

机构地区：[1]中南大学土木工程学院,长沙410075 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《振动与冲击》2011年第2期110-114,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金(90815007);中南大学博士后基金资助项目

摘　　要：在模态推倒分析(MPA)基本概念的基础上,研究了MPA预计非规则梁桥的地震位移需求的具体细节。首先分析了桥梁位移参考点的选择位置、能力谱的形式、非弹性需求谱的构建以及位移组合方式等,然后分别采用MPA和非线性时程分析(ITHA)计算了4座非规则梁桥的横桥向地震位移需求,并比较了MPA与ITHA的计算结果。结果表明,桥墩屈服后,虽然非规则梁桥的各主要模态之间有不同程度的耦合,只要采用合理的MPA操作过程,仍能够得到合理的地震位移需求。Based on basic concept of modal pushover analysis（MPA）,details of estimating an irregular continuous bridge＇s seismic displacement demand with MPA were investigated.Position selection of bridge＇s displacement monitoring points capacity spectrum form,inelastic demand spectrum＇s building and modal combination rules were analyzed with a MPA procedure for an irregular continuous bridge.The lateral seismic displacement demands of four irregular continuous bridges were estimated with the MPA procedure and compared with the rigorous inelastic time-history analysis.Results show that although the irregular continuous bridges mian modes have interactions after their piers yield,the MPA procedure can estimate reasonable seismic displacement demand.

关 键 词：非规则梁桥 推倒分析 抗震设计 基于位移 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]