CYCLIC STABILITY OF STEEL INFILL PLATES WITH TWO-SIDE CLAMPED BOUNDARY CONDITIONS

Steel plate shear wall systems consist of a steel infill plate and boundary elements. It has been paid attention due to their stable hysteretic characteristics including enhanced stiffness and strength capacities. The main purpose of this study is to investigate cyclic stability of steel infill plates with two-side clamped boundary conditions which can avoid welds between plates to vertical boundary elements. A statistical study is first carried out to evaluate the cyclic stability of steel infill plates with two-side clamped boundary conditions. Based on the finite element analysis results of infill plates, regression analyses were conducted to investigate the relationship between response quantities such as plastic rotation capacity and strength degradations, and slenderness parameters for buckling. Evaluation results shows that the response quantities are strongly dependent on the slenderness ratio and the aspect ratio of the infill panels. Based on this observation, this study then focuses on analytically simulating cyclic behaviors of steel infill plates with two-side clamped boundary conditions. Several approaches are adopted including the regression-based equations and/or classification-based machine learning techniques. The important hysteretic characteristics of steel infill plates are carefully selected and major parameters representing those characteristics are estimated using empirical equations. Two types of classification-based machine learning techniques including decision tree model and support vector machine are utilized to structure algorithm which can reduce the mis-estimation of the empirical approach.