Simplified Design Methods for Steel Multi-Tiered Braced Frames in Regions of Low and Moderate Seismicity
Steel multi-tiered braced frames are commonly used in tall single-storey buildings such as airplane hangars, sports facilities or industrial plants to provide lateral bracing when it becomes impractical to use braces that extend the full storey height. Although the multi-tiered configuration offers significant advantages in high seismic areas, it is also the most common option chosen by structural designers in low and moderate seismicity regions of North America. In view of the extensive use of such frames in regions of low and moderate seismicity, improved seismic design methods are needed that address the seismic risk outside of high seismic hazard regions.
The overarching objective of this research project is to provide tools for design engineers and code developers to optimize the design of steel multi-tiered concentrically braced frames in regions of low and moderate seismicity. The project has four specific objectives: i) assess the seismic behavior of frames in regions of low and moderate seismicity in Canada; ii) evaluate current CSA S16 seismic design provisions, with a focus on low-ductile systems, iii) develop simplified seismic design guidelines consistent with CSA S16; iv) evaluate consistency of the proposed design criteria with available prefabricated structural systems.
This research will involve an extensive literature review, parametric numerical studies and experimental studies. Ultimately, design recommendations will be made based on the results of experimental testing and numerical simulations. A simplified format for recommendations will provide an appropriate tool for design engineers dealing with single-storey buildings in Canada. This will reduce the construction cost and keep steel competitive in Canadian industrial market sectors.
This project is the first phase of a larger research program to develop an innovative modular steel structure for industrial buildings with a focus on low and moderate seismic regions.