Evaluation of Stiffness and Strength Degradations Coefficient (C2) for RC Building with Shear Walls

Recently, scientists developed the seismic rehabilitation of structures and their points of view were changed from strength to the performance of structures. Nonlinear Static Procedure (NSP) or pushover analysis is a new method that is chosen for its speed and simplicity in calculations. “Seismic Rehabilitation Code” & FEMA356 considered this method. Result of this analysis is a target displacement that is the base of the performance of the structures. Exact recognition of this displacement could develop the workability of pushover analysis. Although Nonlinear Dynamic Analysis can exactly apply the seismic ground motions, it consumes time, costs very high and is more difficult than other methods. So it is not applicable as much as NSP. A Coefficient used in NSP for determining the target displacement (C2, Stiffness and Strength Degradations coefficient) is applicable for correcting the errors due to eliminating the stiffness and strength degradations in hysteretic-cycles. In this study, three concrete frames with shear walls have been analyzed by several accelerations. After comparing pushover analysis with dynamic analysis, calculated C2 was comprised with values in rehabilitation codes.