Abstract

In this study, a new type of seismic energy-dissipative device in the form of braces based on pre-bent strips has been utilized. In this approach, moment-resistance frame systems have been used for 3, 5, 7, 9, 11 and 12 stories and various models. The height of stories and all span lengths are 3 m. In order to compare the response of models, braced (with damper) and unbraced (without damper) have been modeled. Pre-bent steel strips have been used in braced frames. A bilinear strain-stress model of mild steel has been used in this simulation. The responses of structures with dampers and without dampers under dynamic loading have been compared. The results show that seismic responses, such as base shear, story acceleration and story velocity of 3, 5, 7, 9, 11 and 12 story frames with dampers have been improved (reduced) and these reductions have been decreased from 3 story frames to 12 story frames. This damper reduces the displacement of models on upper stories. A series of time history inelastic dynamic analyses have been conducted and the results show the feasibility and effectiveness of using the utilized devices as seismic dampers to reduce structural responses, such as base shear, acceleration, velocity and displacement of stories. This new kind of dissipative device controls seismic damage and reduces story responses under cyclic loading.

Key words: Pre-bent strips, response of structure, damper, energy dissipation.