Prescriptive Approach to the Performance-Based Seismic Design of Low-Rise Wood-Frame Residential Buildings

Abstract

Performance-based seismic design (PBSD) is considered by many to be the next generation of design philosophy that focuses on the system performance of a structure during earthquake loading. For steel and concrete structures, this design philosophy is being used by a select group of practitioners. However, application to wood-frame buildings is still in the research stages; several approaches for PBSD are proposed with rehabilitation concepts available in ASCE 41. Currently, most of the PBSD methods for wood-frame buildings require designers to utilize a level of approach that is far more detailed than current design approaches. This increases the cost of any engineering for the design of wood-frame buildings. Therefore, in this study, a simplified design approach is developed that allows a designer to employ the PBSD methodology without complex analysis. Different from most existing PBSD procedures, this prescriptive approach was developed based on a significant number of numerical simulations using a simplified, nonlinear time history model that represented typical one- and two-story light-frame wood residential buildings. The final format of this simplified PBSD procedure is similar to the prescriptive tabular format in current design codes such as the National Design Specification for Wood (NDS). These tables enable selection of shear wall configuration based on a building’s performance expectation. Two design examples were used to illustrate this prescriptive PBSD procedure. Each of the final buildings designed using this procedure was then verified using a detailed nonlinear numerical model. The method was shown to be approximately 5 to 10% conservative, on average, from an exceedance probability standpoint for interstory drift limits.