EFFECT OF STRUCTURAL PARAMETERS ON STRAIN CONCENTRATION MODIFICATION COEFFICIENT FOR THICK-WALLED STEEL MEMBERS

Abstract

 The present study is aimed at improving a simplified evaluation method of the ductile crack initiation for unstiffened box sectional steel bridge piers. By performing elasto-pastic analyses using the shell element model, effects of structural parameters such as plate width-thickness ratio, column slenderness ratio as well as plate thickness on plastic strain are investigated. By comparing with those from elasto-plastic analyses using the beam element, an equation of strain concentration modification coefficient is obtained for the damage evaluation method based on the fiber analysis using the beam element. It is confirmed that the simplified method of applying the newly proposed strain concentration coefficient equation in the damage evaluation formula is possible to predict the ductile crack initiation as accurate as the previous method by shell analysis and its validity is also verified by comparison with experiment results.