摘要
对基于能量的多模态推覆分析方法(Energy-based Modal Pushover Analysis,EMPA)估计高墩地震响应的有效性进行了研究。以一座典型高墩桥梁为例,采用EMPA方法计算了高墩的地震响应,并与非线性时程结果相比较。结果表明:采用EMPA方法计算高墩墩身的位移峰值及剪力峰值时,与非线性时程结果相比误差在30%以内,具有较好的精度;而计算截面曲率时最大误差达到了50%。结果还表明:对桥墩位移进行估计时采用一阶推覆结果即可获得较好的精度;对截面曲率及墩身剪力估计时则应采用更多阶数的响应结果进行组合以获得正确的结果。针对一阶振型参与质量系数较大的桥墩(30 m、60 m),对截面曲率及墩身剪力的估计可采用前两阶的结果进行组合,而对一阶振型参与质量系数较小的高墩(90 m),应采用前三阶的结果进行组合。
An energy-based modal pushover analysis procedure for estimating seismic demand of tall piers is introduced in this paper,of which the effectiveness is demonstrated with a 90 m-high bridge pier modelled with fibre elements.The result,compared with that of nonlinear time history analysis,shows that responses,including peak displacement,peak curvature and peak shear force of the pier,can be estimated effectively.Meanwhile,the peak displacement can be estimated with the first modal response,while the curvature and shear force with more.For piers(30 m,60 m)with large participation mass ratio of the first mode,the curvature and pier shear can be estimated with the first two modes;for the high piers(90 m)with small participation mass ratio of the first mode,the results of the first three modes should be combined.
作者
周迅
唐耀明
李建中
徐艳珊
ZHOU Xun;TANG Yaoming;LI Jianzhong;XU Yanshan(Department of Bridge Engineering,Tongji University,Shanghai 200092,China;Yunnan Gongdong Expressway Construction Command Post,Kunming 650000,China)
出处
《结构工程师》
2021年第5期79-89,共11页
Structural Engineers
基金
云南省交通运输厅(云交投发[2020]768号)。
