The objective of this paper is to investigate the seismic capacity of RC frame. In order to modify the forecast to the initial stiffness of frame,and improve the conveniency and accuracy for the calculation of strain energy. The original RC frame can be transferred into an equivalent trusslized model according to RC member behavior dealing with the concrete and steel stressed properties. Then, the seismic capacity of RC frame can be assessed by adopting the Pseudo-elastic analyss to the equivalent trusslized model .

Firstly, the stress-strain behavior model for steel and concrete should be defined, and this model can be simplified and applied to calculate the strain energy of axial force quickly. Secondly, the original RC frame can be transferred into an equivalent trusslized model. Then, the member behavior and the Pseudo-elastic response can be figured by using the SAP program and magnifying seismic lateral force step by step. According to the concept of Pseudo-elastic approach, the nonlinear strain energy can be transferred by the strain energy exceeding the linear range. Finally, the nonlinear response of structure can be obtained. Thus, seismic capacity can be assessed according to ultimate base shear and roof displacement.

A series of RC frames with experimental data are analyzed for seismic capacity in this thesis.The acceptable accuracy and reliability of trusslized Pseudo-elastic approach for seismic capacity can be verified by comparing with experimental data and Pushover analysis results.