河北工业科技2024，Vol.41Issue(6)：434-442,9.DOI:10.7535/hbgykj.2024yx06005
基于模态柔度的损伤连续梁桥虚拟荷载试验方法研究
Research on virtual load test method for damaged continuous beam bridges based on modal flexibility
摘要
Abstract
In order to quickly evaluate the bearing capacity and actual operating status of continuous beam bridges,a virtual load test method based on modal flexibility was proposed.Taking a 3-span continuous beam bridge of a certain actual project(40+40+40)m as the research object,numerical simulation methods were used for in-depth analysis.The elastic modulus of the main beam unit was reduced by 30%to simulate the bridge damage,and SSI modal parameter identification technology was used to identify the modal parameters of the damaged bridge under white noise excitation to construct the displacement flexibility matrix.A virtual load test plan was designed to predict the modal deflection of damaged bridge under the virtual load,and the structural verification coefficient was calculated.The results show that under environmental excitation,only 42 measuring points need to be arranged at the quarter point section of a 3-span continuous beam bridge to accurately identify the dynamic characteristic parameters of the continuous beam bridge;Only the first 6 modal parameters are needed to predict the modal deflection of key sections of continuous beam bridges under virtual load tests;The structural verification coefficients of the 3-span continuous beam bridge under unbalanced and medium load conditions are all greater than 1,indicating that the bearing capacity of the bridge does not meet the design requirements and requires timely maintenance.The virtual load test method based on modal flexibility has certain application potential in evaluating the actual bearing capacity of 3-span continuous beam bridges,can provide reliable technical support for engineering practice.关键词
桥涵工程/环境激励/模态柔度矩阵/模态挠度/虚拟荷载试验Key words
bridge and culvert engineering/environmental excitation/modal flexibility matrix/modal deflection/virtual load test分类
交通工程引用本文复制引用
张方圆,亓兴军,黄岩,张炜..基于模态柔度的损伤连续梁桥虚拟荷载试验方法研究[J].河北工业科技,2024,41(6):434-442,9.基金项目
山东省交通运输厅科技计划项目(2022B06) （2022B06）
山东省企业技术创新项目(202250101726,202160101415) （202250101726,202160101415）
