A STUDY ON STRAIN CONCENTRATION MODIFICATION COEFFICIENT IN EVALUATION METHOD OF DUCTILE CRACK INITIATION FOR STIFFENED BOX-SECTIONAL STEEL BRIDGE PIERS

Abstract

 This study is aimed at proposing an evaluation method of ductile crack initiation for stiffened box-sectional steel bridge piers using beam element analysis. Through shell element analysis and beam element analysis, the difference of strain concentration phenomenon between them is investigated. The influence of structural parameters such as plate width-thickness ratio parameter, column slenderness ratio parameter, and plate thickness on strain concentration modification coefficient is discussed. As a result, a general expression of strain concentration modification coefficient for stiffened box-sectional steel bridge piers is proposed. By applying the damage index with the proposed strain concentration modification coefficient, it is demonstrated that the beam element analysis could also evaluate ductile crack initiation with almost the same accuracy as the shell element analysis.