Development of Modal Strain Energy Method Combined with Multi-phase Genetic Algorithm for Structural Damage Detection in Plates

Abstract

AbstractThis study develops a two-stage damage detection procedure using the modal strain energy method combined with a multi-phase genetic algorithm for structural damage detection in plate-type structures. In the first stage, a modal strain energy damage index (MSEDI) based on the modal strain energy change is used to detect the occurrence and location of the potential damages. In the second stage, an iterative genetic algorithm, namely a multi-phase genetic algorithm, is deployed to eliminate wrong detected elements resulting from the previous stage. The objective function with the variables relating to the vector of stiffness reduction of the potentially damaged elements is calculated based on modal strain energy change on the local damaged area. An aluminum plate is used to verify the proposed procedure's effectiveness and feasibility with several damage scenarios. The result shows that the multi-phase genetic algorithm can improve the accuracy of identifying the location and the extent of damages compared to the original genetic algorithm.KeywordsDamage detectionMulti-phase genetic algorithmModal strain energyPlate-type structureTwo-stage procedure