Impact behavior of beam-column joint with geometric imperfections at weld root

Abstract

This study numerically investigates dynamic response of welded beam-column joint with different weld imperfections at weld root. The imperfections at weld root, such as incomplete root penetration, shrinkage groove and root concavity, are considered in this study. The size and shape of these imperfections are determined in accordance with ISO 5817 code. Numerical model of welded beam-column joint with imperfections is developed and calibrated by the test results of welded beam-column joint without imperfection under impact load as well as the numerical results of butt-welded joint with grinding profile under static load. The factors of the imperfections, such as the distribution and length of imperfections and the weld quality levels are considered to investigate their effects on the damage mode, dynamic response, and energy dissipation of welded joints subjected to impact loads, as well as the post impact behavior of the joint. Parametric study is carried out to investigate the effect of impact velocity and impact mass on welded joint with different root imperfections. The effect of different weld imperfections on the energy dissipation of joint is also investigated. The most vulnerable form of root imperfection is identified by comparing the joints with different imperfections in terms of damage mode, dynamic response and energy dissipation.