Abstract

Ductile Steel Plate Shear Walls (SPSWs) have been accepted widely as a very effective lateral load resisting system. However, their use in retrofit works is very limited because of the design inefficiency arising from the use of thicker than required commercially available infill plates. Consequently the ductility demand for the surrounding framing members is higher than required. SPSWs utilizing light-gauge cold-formed infill plates could be a viable alternative for rehabilitation of seismically deficient buildings. This thesis presents a numerical study using finite element models on the behavior of unstiffened light-gauge steel plate shear walls with welded infill plate connection. The detailed finite element models include both material and geometric non-linearity. This research describes in detail the validation of the key finite element models by comparing the results with that from the available experimental studies. Excellent correlation between the test results and the finite element analysis results has been achieved.

For seismic performance evaluation of a multi-storey building with SPSWs, detailed finite element models or a strip model can be used to represent the SPSW components. However, development and analysis of such models often require undesirable effort and excess time for high-to-medium rise buildings. A simplified model is developed in this research to study the behavior of SPSW system. In the simplified model, discrete elements are used for the framing members and the behavior of the infill plate is represented by equivalent diagonal bracing members. The simplified model, Equivalent Braced Model, is developed through repeated static and dynamic validations with experiment and detailed finite element models. The proposed Equivalent Braced Model would facilitate a simplification to the structural modeling of large buildings with SPSWs in order to evaluate the seismic performance using regular structural analysis tools and can prove to be a potential aid in performance-based seismic design of SPSW buildings. Finally, the developed equivalent braced model and the detailed finite element model are used to analyze three multi-storey light-gauge SPSWs (four-storey, six-storey and ten-storey) designed according to the capacity design approach.