Development and application of an advanced capacity spectrum method

In this study an advanced capacity spectrum method (CSM), incorporating inelastic response history analysis is proposed. By employing inelastic response history analysis, the errors introduced due to the use of equivalent linear approaches are eliminated. The available variants of the CSM and the proposed method are used for the evaluation of the seismic response of a woodframe structure. The results are compared to experimental test data. It is observed that more accurate results are obtained with the method proposed in this paper, while the existing CSM approaches exhibited several shortcomings. These shortcomings include failure to predict the displacement demand, incompatibility between the demand and capacity diagrams and non-convergence. It is also observed that updating the bilinear idealization of the structural system according to the selected trial performance point on the capacity diagram significantly improves the accuracy of the CSM.