基于加速度响应监测的桥址地震动辨识研究  

Ground motion identification of bridge site based on acceleration response monitoring

作　　者：陈太聪[1] 洪辉煌 CHEN Taicong;HONG Huihuang(State Key Laboratory of Subtropical Building Science,School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]华南理工大学土木与交通学院亚热带建筑科学国家重点实验室,广州510641

出　　处：《振动与冲击》2021年第7期89-94,共6页Journal of Vibration and Shock

基　　金：广西科学研究与技术开发计划(1298011-1);亚热带建筑科学国家重点实验室项目(2017KB13)。

摘　　要：在桥梁结构的健康监测实践中,利用结构动态响应进行桥址地震动辨识,对于结构安全评估具有重要意义。根据桥址场地特征,确定非平稳地震动模型和相关方差函数。建立地震动辨识问题的数学模型,基于极大似然估计原理推导得到实际地震动时程的递进识别算法,其中加速度响应的灵敏度对应离散化的脉冲响应函数。以某三跨刚构桥受横向地震为数值算例,从传感器数量与观测噪声影响两方面,考察方法辨识效果。结果表明,辨识方法对传感器数量要求不高,抗噪性能好。开展结构模型振动台试验,进一步检验了方法效果。In health monitoring practice of bridge structures,using structural dynamic responses to identify bridge-site’s ground motion is very important for structural safety evaluation.Here,firstly,according to characteristics of bridge site,a non-stationary random process model was chosen to describe ground motion,and the corresponding variance function was derived.Then,a mathematical model was established for the ground motion identification problem.Based on the principle of maximum likelihood estimation,a progressive identification algorithm of real ground motion time history was deduced,in which the sensitivity of acceleration response corresponded to the discretized impulse response function.Taking a 3-span rigid frame bridge subjected to lateral earthquake as a numerical example,the identification effect of the proposed method was examined from two aspects of number of sensors and influence of observation noise.The results showed that the proposed identification method does not require a large number of sensors and has good anti-noise performance.Finally,shaking table tests of structural model was conducted to further verify the effectiveness of the proposed method.

关 键 词：健康监测 地震动辨识 加速度响应 极大似然估计 

分 类 号：O327[理学—一般力学与力学基础] TU317[理学—力学]