Analysis and design optimization approach of vibration characteristics of an I shaped straight steel girder bridge

Abstract

Bridges are subjected to environmental exposure like corrosion which may induce cracks. These cracks may cause change in natural frequency of bridge. The current study's goal is to explore the effect of crack on the vibration characteristics of bridge the design and modal analysis of bridge is conducted by ANSYS 21 simulation package. Two different designs of bridges are evaluated i.e. without crack and with crack.The effect of crack on natural frequency and mode shape is evaluated. The vibration characteristics of bridge structure changed with artificially induced transverse elliptical crack on girder.Techniques of optimization could help in determining the behaviour of the damage and extent to which it could be controlled via simulation technique without conducting tests on the actual model. Analysing the frequencies using ANSYS software, the validity of the presented numerical formulation is studied. Response spectrum methodology is used in studying the crack characteristic and optimization of crack variables. Sensitivity analysis showed the individual effect of each variable on the output parameters. Moreover, the response surface plots generated showed the peak and least deformation values of natural frequencies. Invaluable information which help practicing engineers better understand the vibration characteristics is provided.