应变模态法在桥梁损伤识别中的应用

摘要

基于应变对局部损伤的敏感特性,引入应变模态法,通过比较完好桥梁和损伤桥梁的应变模态变化,即可判断桥梁损伤的位置和程度.首先在理论上给出了应变与振动模态之间的详细表达式；然后基于大型通用商用有限元软件ANSYS,对金属模型桥梁进行数值仿真模拟以及识别试验、数据分析；最后,应用应变模态法对厦门市石鼓山立交桥进行现场损伤识别,得到了该桥梁的服役状态,为桥梁质量评估和维护提供了可靠的依据.%Based on sensitive characteristics of strain on partial damage, the strain mode method was introduced to judge bridge damage location and degree, by comparing changes of strain mode between intact bridge and damaged bridge. This paper first enriched the strain mode damage recognition method in theory, and gave detail expression between strains and vibration modes; then the metal model beam were numerical simulated by applying with large general commercial finite element software AN-SYS; finally, this strain mode method was specifically applied to damage recognition of Xiamen Shigu hill overpass, and got the bridge's service state, also provides the reliable basis on the bridge quality evaluation and maintenance.