Seismic Response of RC Frames with Steel Braces

Abstract

Steel bracing members are widely used in steel structures to reduce lateral displacements and dissipate energy during strong ground motions. This concept is extended to concrete frames Inelastic seismic response of reinforced concrete frames with K and X steel bracing patterns is presented. A two bay six story frame designed by limit state design procedure was subjected to 1.25 times the North‐South component of the 1940 El Centro earthquake and the artificially generated B1 earthquake. Takeda's bilinear hysteresis model was assumed for girders, an elastoplastic model was assumed for columns with axial force effects included, and a multilinear buckling model was assumed for steel bracing members. It is concluded that the inelastic response of both the K and X braced frames are satisfactory under the modified El Centro earthquake The response of X braced frame is much better compared to that of the K braced frame under the modified B1 earthquake. It is also noticed that there is a considerable increase in the column axial forces due to the presence of bracing members, which is typical of braced frames.