基于监测的跨海索桥动态特性受环境影响分析  

Analysis of Dynamic Characteristics of Sea-crossing Cable Bridge Affected by Environment Based on Monitoring

作　　者：苗祥泰 孙宗光[1] 赵洪伟 MIAO Xiang-tai;SUN Zong-guang;ZHAO Hong-wei(Road and Bridge Research Institute,Dalian Maritime University,Dalian,Liaoning 116023,China)

机构地区：[1]大连海事大学道路与桥梁研究所,辽宁大连116023

出　　处：《黑龙江交通科技》2022年第4期70-73,共4页Communications Science and Technology Heilongjiang

基　　金：国家自然科学基金资助项目(51178070);中央高校基本科研业务费专项资金资助(3132014326,3132016216)。

摘　　要：由于环境与运营条件的变化,基于监测信息识别的桥梁结构的动态特性具有一定的时变特征。掌握和量化这种变异特征,是基于结构动力指纹识别结构状态及相关应用的前提。选择三座海洋环境下特殊类型的索桥,分别为稀索斜拉桥、独柱式三塔斜拉桥、独柱式单塔自锚悬索桥,基于运营监测数据对全年不同季节的温度影响和强风环境下的振动频率的变异性进行了分析。总体上,温度对低阶频率影响较小,频率对温度的敏感性随着频率阶次的升高而增大,并呈现显著的线性负相关。平均风速和桥梁结构频率之间的关系存在较大的离散性,但是随着平均风速的增大,频率总体上呈下降趋势。就斜拉桥实例分析表明,当平均风速从10 m/s增大到35 m/s时,第1阶竖弯模态频率平均下降约6%,第4阶平均下降约4%。Due to the change of environment and operation conditions,the dynamic characteristics of bridge structure based on monitoring information recognition have certain time-varying characteristics.Mastery and quantification of this variation feature are the premise for identification of structural state based on dynamic fingerprints.This paper choose three special types of bridges in marine environment,cable-stayed bridge with large cable spacing,three-tower cable-stayed bridge,single-tower self-anchored suspension bridge.The variability of vibration frequency is analyzed based on the monitoring data that influenced by the temperature of different seasons and strong wind.Temperature has a small influence on low frequency,and the sensitivity of frequency to temperature increases with the increase of frequency order,and presents a significant linear negative correlation.The relationship between average wind speed and frequency is very discrete,but with the increase of average wind speed,the frequency generally declines.According to the case analysis of cable-stayed bridge,when the average wind speed increased from 10 m/s to 35 m/s,the average frequency of the first vertical bending mode decreased by about 6%,and the fourth order decreased by about 4%on average.

关 键 词：跨海索桥 监测数据 动态特性 环境因素 

分 类 号：U442[建筑科学—桥梁与隧道工程]