王蕾,侯吉林,欧进萍.基于荷载形函数的大跨桥梁结构移动荷载识别[J].计算力学学报,2012,29(2):153~158,177 |
| 码上扫一扫! |
基于荷载形函数的大跨桥梁结构移动荷载识别 |
Moving force identification based on load shape function for a long-span bridge structure |
投稿时间:2011-12-25 修订日期:2012-02-10 |
DOI:10.7511/jslx201202001 |
中文关键词: 结构健康监测 移动荷载识别 形函数 脉冲响应 大跨桥梁 |
英文关键词:structural health monitoring moving force identification shape function impulse response long-span bridge structure |
基金项目:国家自然科学基金(51108057);国家科技支撑 计划(2011BAK02B01);中国博士后科学基金 (20110490142)资助项目. |
|
摘要点击次数: 3712 |
全文下载次数: 1874 |
中文摘要: |
大跨桥梁结构中的移动荷载识别是结构健康监测的重要组成部分之一,其作为动力学中的反问题,存在唯一性及稳定性等病态问题。本文首先推导出移动荷载作用下结构响应的卷积形式的离散公式,然后利用有限元理论中的形函数拟合移动荷载,推导出基于荷载形函数的移动荷载识别表达式。将移动荷载的识别转化为荷载形函数拟合系数的识别,降低了需要识别的未知量,减小了逆运算的计算量,消除或减弱逆问题病态性,并提高了计算效率。利用某大跨刚构-连续预应力混凝土桥梁修正后的有限元模型进行数值仿真,考虑路面粗糙度,由模态叠加法计算移动荷载作用下的响应;然后采用荷载形函数方法识别移动荷载,证明该方法在5%以下的噪声时能快速并精确识别复杂桥梁结构的移动荷载。 |
英文摘要: |
Moving force identification of long-span bridges is an important part of structural health monitoring,and as an inverse problem,it is ill-conditioning with uniqueness and stability problems.This paper deduced the discretized formulation of structure responses to moving force,employed the shape functions from the finite element method to fit the time history of moving force,and developed the moving force identification formulas based on load shape functions.The identification problem of moving force was transformed into determining the fitting coefficients of load shape functions,which decreased the unknown parameters,reduced calculation in the matrix inverse operation,removed or weakened the ill condition and promoted computational efficiency.To evaluate the proposed algorithm,a prestressed rigid-continuous concrete bridge was simulated by its modified finite element model,which subjected to moving force considering road roughness.The responses were analyzed by mode superposition technique,and moving force was estimated by load shape functions.Results show that the moving force with noise below 5% can be identified for complex bridges efficiently and accurately. |
查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|