THE STUDY OF X-BRACING ON LIMIT STATE BEHAVIOR OF BUCKLING RESTRAINED BRACE (BRB) IN STEEL FRAMES USING PUSHOVER ANALYSIS

Using energy dampers in structures is highly considered for the dissipation and absorption of earthquake energy. The main advantage of using energy dampers is absorbing the earthquake energy in some sections apart from the structure. Among different types of dampers, hysteresis dampers are of special place because of low cost, high reliability and the lack of mechanical parts. In this paper, a special kind of hysteresis damper is considered under the name of buckling brace, which is provided with the aim of the study and investigation of X-brace in the seismic behavior of the steel framed buildings and for pipe and equipment racks that are extensively used in the oil and gas industry. In this paper, 62 models of steel frames with X-brace and buckling type damper are processed with different bays and heights. The frames' plasticity index, behavior coefficient, distribution type and the number of plastic hinges formed were calculated. Furthermore, suitable locations of braces for improving nonlinear behavior and suitable distribution of plastic hinges were presented and it was determined that for some models, the behavior coefficient of structure will increase to 1.5 times.