Displacement-based performance assessment of RC shear walls designed according to Canadian seismic standards

Performance-Based Seismic Design (PBSD) methods were developed as an alternative prescriptive current building codes. The underlying logic behind these techniques is to link specified structural performance objectives to one or more earthquake hazard levels. Most research on PBSD methods was validated using Western North America (WNA) ground motions however. This project aims mainly at investigating the use of some Displacement-Based approaches to assess the seismic performance of Reinforced Concrete (RC) shear walls in a Canadian code perspective.; The inelastic seismic response of reinforced concrete shear walls, as main members of the Seismic Force Resisting System (SFRS) was investigated using current engineering practice and compared to the seismic response after applying PBSD methods. Three reinforced concrete frame-shear wall office buildings with the same floor plan were investigated in the present study. The three buildings have different heights of 21 m, 42 m and 63 m corresponding to 6, 12 and 18 storeys, respectively. Seismic design and performance assessment of the three shear wall buildings were conducted assuming that they are located at the cities of Montreal, Quebec, and Vancouver, British Columbia, to account for seismic hazard in Eastern and Western Canada, respectively.; Seismic provisions of current generation of building codes including the National Building Code of Canada (NBCC 2005), advocate the use of Force-Based Design (FBD) procedures. According to this approach, elastic base shear required to keep a ground shaken structure linear-elastic was first determined. Smoothened soil dependent elastic spectral accelerations were used for this purpose. The structure was then designed to have a yield strength obtained by dividing the elastic base shear by a force modification factor. This reduction factor depends on the lateral force-resisting system used, and is assumed to account for the structure's ductility capacity and inherent overstrength. The shear walls studied were assumed as ductile (Rd = 3.5). The structures were then subjected to a set of equivalent lateral forces obtained from the vertical distribution of the design base shear over the building height. Once the resulting deformations were checked to be within code prescribed limits, proportioning and detailing of the structural members followed.; Three Displacement-Based Design (DBD) approaches were explored in this work: (i) the Yield Point Spectra method (Aschheim, 2000), (ii) the Direct Displacement Based-Design method (Priestley and Kowalsky, 2000), and (iii) the Inelastic Displacement Spectra method (Chopra and Goel, 2001). To facilitate the understanding of the theoretical background of the three DBD techniques investigated, a unified mathematical formulation of the three methods was first developed in this project. The three techniques were developed initially for Single Degree of Freedom (SDOF) systems. They are based on inelastic response spectra, that can be derived from elastic spectra using ductility dependent factors.; The methodology of the three DBD procedures aims at a direct displacement-based structural design. They are indeed formulated to satisfy modern seismic design strength criteria and in the meantime to assist structural engineers to limit maximum deflections and inter-story drifts to acceptable values. In order to achieve these objectives, the conceptual methodology implements the use of an equivalent structural model of one degree of freedom. The present thesis also presents a new method of estimating the target displacement and the inter-story indexes of the multi-story buildings throughout establishing formulas for the deformed building shape, developed on the basis of the first deformation shape. Nonlinear time history analyses of the concrete shear walls were performed using site-specific ground motions for Montreal and Vancouver. Both synthetically generated and historical records were considered for the analyses...