SEISMIC BEHAVIOR OF STEEL RIGID FRAME WITH IMPERFECT BRACE MEMBERS

Model of a steel rigid frame made of thin-walled box section with existence of I-section brace member with initial overall and local imperfection adopted to investigate buckling effects on steel structural behavior as it was subjected to earthquake excitation. In order to take into account of the influence of local deflections on structural response, shell elements were employed to model brace member as well as base columns. Cross sections components with relatively high amplitude of buckling parameters were considered in different ca se studies to make it susceptible to develop local deflection. Beam elements were also utilized to develop models with the same specification. FEM method applied to conduct nonlinear time history analysis using earthquake record in in-plane and out-of-plane direction.