多点激励下多跨斜拉桥缩尺模型的地震响应研究.部分2:数值分析（英文）  

Seismic response study on a multi-span cable-stayed bridge scale model under multi-support excitations. Part II: numerical analysis

作　　者：Rui ZHOU Zhou-hong ZONG Xue-yang HUANG Zhang-hua XIA 

机构地区：[1]State Key Lab for Disaster Reduction in Civil Engineering, Tongji University [2]School of Civil Engineering, Southeast University [3]School of Civil Engineering, Fuzhou University

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2014年第6期405-418,共14页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：supported by the National Natural Science Foundation of China(Nos.51178101 and 51378112);the Doctoral Program Project of the Ministry of Education(No.20110092110011);the NationalKey Laboratory of Civil Engineering Disaster Prevention of Tongji University(No.SLDRCE08-HZ-02),China

摘　　要：研究目的:通过非线性动力有限元分析,模拟多塔斜拉桥在多点激励下的地震响应以及揭示其在强震下的倒塌破坏模式。创新要点:解决了多塔斜拉桥的非线性动力数值模拟技术,并首次模拟了多塔斜拉桥在强震下的破坏模式。研究方法:首先采用隐式的Newmark-β法求解多点地震激励下的非线性动力方程(图3),随后采用显式的中心差分格式对强震作用下桥梁的倒塌破坏过程进行数值仿真(图4)。重要结论:1.单主梁模型的数值结果可以很好地反映地震模拟振动台试验的地震响应结果;2.在加速度峰值为4.0 m/s2的El-Centro波时,多塔斜拉桥模型只出现了中塔支座的破坏;3.在加速度峰值为4.0 m/s2的江心波时,多塔斜拉桥模型先后出现了支座破坏、拉索与塔的连接破坏以及中塔上塔柱段的单元失效。In recent years, local component destruction, collapse failure and the control of long-span cable-stayed bridges under strong multi-support excitations have received increasing attention. In this paper, two kinds of nonlinear finite element （FE） models are established to simulate the seismic responses and failure modes of a multi-span cable-stayed bridge scale model under multi-support excitations. One is the single girder model which is used to simulate the seismic response during four wave excitations. It can be concluded that the FE analysis results of the scale model are a good fit with those from the shaking table tests. The other one is the explicit dynamic FE model which is used to simulate the collapse and failure mechanisms of the scale model during strong earthquakes. The aggressive failure processes of the scale model under two different types of wave excitations were compared to reproduce the mechanisms in which the bearing at the middle tower failed under the E1 Centro （EC） wave （4.0 m/s2）, and we also observed the connection failure of the cables and towers, and the elements failure of the upper beam in the middle tower, which occurred successively under a Jiangxin （JX） wave （4.0 m/s2）. This simulation may be referenced as the basis for the collapse failure of a cable-stayed bridge with a large span during a strong earthquake.

关 键 词：多塔斜拉桥 非线性有限元分析 多点激励 破坏模式 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]