Estimation of Response Modification Factor of Precast Concrete Frames with Semi Rigid Connections strengthened with X-Steel Bracing

As the population grows, the importance of creating more buildings in the short term and at low cost, such as prefabricated structures, becomes more apparent. For this purpose, in this research using SAP 2000-14 software, three kinds of 2, 4 and 6-story RC frames were designed by considering connection rigidity. Three types of connection rigidity including pinned, semi-rigid and rigid precast RC connections were applied to estimate response modification factor (R) of designed frames. It is worth mentioning that each of the frames has five bays and the length of each of the bays is 5 meters with the exception of median bay that is 4 meters strengthened with X-steel bracing. Then the nonlinear static analysis was applied to evaluate the effect of frame’s height and connection rigidity on response modification factor of designed frames. The results presented that with increasing the rigidity and frame’s height R factor is increased.