Study On Damage Identification Of High Way Bridge Based On Curvature Mode Theory

The whole High way bridges in Beijing have certain damages for poor naturalconditions, long history, overload or some other reasons. According to safety andeconomy, it is quite valuable for development of Beijing city to master the damageinformation and do corresponding maintenances for these High way bridges in time.As one part of project An intelligent decision technology for damage identificationand maintenance of Highway Bridge in Beijing which is one of Beijing NaturalScience Funds, this paper mainly focus on the study of the application of the idealdamage identification parameter named curvature mode. Curvature mode canperfectly reflects local characteristics variety of structure. It can be obtained throughseries modes of structure, whose sensibility excels mode and frequency. The easiestmethod to obtain curvature mode is to work out the displacement mode first, thencalculate the curvature mode by displacement difference method. Theoreticallyspeaking, certain crack or damage in structure will result in reduction of stiffness inthis part, which in turn increase the curvature rate and bring on mutation of curvaturemode numerical value. Damage can be detected according to this principle.Aimed at some insufficiencies of curvature mode research in damage identificationfield and in view of its application in this project, some improvements to the researchobjective and research methods are pointed out in this paper.Mainly work is as follows: 1 Upgrade the simple damage beam with stiffness reduction element model incommon research to simple damage beam with directional crack in this paper; II摘 要 2 Process curvature mode curve by numerical differentiation, which make thecurve more sensitive to damages than before; 3 Establish large-sized finite element model referred to real city High way bridgedata. Imitate deck constitution, pier constitution and connection between them indetail. Then, analyze the influences of these characteristics to curvature mode, whichcan provide reference to mode measurement in site and damage identification of HighWay Bridge in practical.