PUSHOVER ANALYSIS-BASED SIMPLE METHOD FOR DUCTILE CRACK INITIATION EVALUATION OF STIFFENED BOX-SECTIONAL STEEL BRIDGE PIERS

Abstract

 This study is aimed at developing a simple method for ductile crack initiation evaluation of stiffened box-sectional steel bridge piers by means of pushover analysis. The general expression of the strain concentration modification coefficient for stiffened box-sectional steel bridge piers is reexamined to improve the accuracy when the plate thickness is relatively thin. Pushover analysis is performed on the fiber model using beam elements. A method to obtain the ductile crack initiation critical strain at structural level is devised by dividing the ductile crack initiation critical strain at material level by the strain concentration modification coefficient. In addition, a method for determining the critical displacement of ductile crack initiation is proposed by applying the ductile crack initiation critical strain at structural level to the pushover analysis results as the failure criterion, and its applicability is examined.