Performance-Based Seismic Design With Consideration of Safe Storage From Errors in Reinforced Concrete Member Estimated Yield Deformation

Abstract

While performing the capacity spectrum method in seismic design, it is essential to select a reasonable objective. In practice, the design objective is typically determined by estimated structural response. However, factors like ground-motion randomness, the deviation between the structural analysis model and the actual behavior, and other factors would introduce errors in estimation. Therefore, a redundancy design with consideration of safe storage from these errors is necessary. This study focused on errors in the structural analysis model specifically, particularly reinforced concrete members’ estimated yield deformation—an essential parameter in estimating structural response. Initially, the influence on yield deformation of the structure due to each member's estimated yield deformation was clarified theoretically in the capacity spectrum method. To supplement theoretical analysis, a pushover analysis was conducted based on an E-defense shaking table test specimen. Then, the effect of structural yield deformation on estimated response deformation was deduced according to Japanese seismic design guidelines and was verified based on a single-degree-of-freedom (SDOF) numerical analysis. By integrating these discussions, errors in estimated structural response caused by members’ estimated yield deformation can be evaluated. Consequently, a redundancy factor was proposed to include the safe storage from errors in RC member estimated yield deformation.