桥梁断面颤振导数识别的耦合自由振动测力法  

Coupled Free Vibration Force Measurement Technique for Identifying Flutter Derivatives of Bridge Decks

作　　者：吴昊[1,2] 

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

出　　处：《佳木斯大学学报（自然科学版）》2014年第4期487-490,495,共5页Journal of Jiamusi University：Natural Science Edition

基　　金：国家自然科学基金重大研究计划"重大工程动力灾变"集成项目(91215302)

摘　　要：随着桥梁跨度的不断增加,桥面风致振动所引起的气动力非定常效应和非线性效应较为显著,钝体断面的自激力高次谐波分量不可忽略.为研究非线性自激力特性,课题组开发了一套高精度测力天平.利用此天平首先采用Scanlan线性自激力模型测得桥梁断面颤振导数,并与修正最小二乘法识别结果进行对比,再用Newmark-β法反算位移,取得了很好的结果,验证了天平的可靠性.本方法因适用于非线性自激力研究,为下一步工作建立非线性自激力模型提供了很好的手段.With the increasing of the bridge span , aerodynamic unsteady and nonlinear effect caused by wind-induced vibration of bridge decks is more obvious , and the high harmonics of self -excited force in the bluff section should not be ignored .In order to study the nonlinear characteristics of self -excited force , our research group developed a high precision force balance .With the balance bridge section flutter derivatives were measured using Scanlan＇s linear self-excited force model , then the results were compared with those identified by MLS method .Furthermore , the New mark-βmethod was used to calculate displacement reversely , which achieved good results and verified the reliability of the balance .Applicable to study nonlinear self -excited force , the method provides a good means for the establishment of nonlinear self -excited force model in the future .

关 键 词：桥梁断面 自激力 测力 颤振导数 耦合自由振动 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]