Achieving Improved Construction Efficiency for Multi-Story Steel Concentrically Braced Frames

Volumetric steel modules were proposed in this study to improve construction efficiency of multi-story steel concentrically braced frames. Two types of modules, (1) gravity modules and (2) braced modules, which features the steel concentrically braced frame (CBF) system, are first introduced. The proposed braced module consists of steel CBFs to carry lateral seismic or wind loads. The module assembly and construction sequence are then presented. The structural design of the modules is performed in accordance with the Canadian steel design standard. An analysis of the structural costs is then carried out on a prototype building consisting of the volumetric modules to evaluate the cost efficiency of the system as compared to a conventional braced frame system. The gravity and lateral load-carrying capacities of a two-story CBF subassembly are finally examined under lateral seismic loads using continuum-based finite element analysis with emphasis on the inelastic response of braces. The results of the cost analysis confirm the potential benefits offered by volumetric gravity and braced modules to improving construction efficiency of steel CBFs through off-site construction of the modules and on-site assembly. Furthermore, the results obtained from the structural response evolution of the CBF subassembly suggest an acceptable lateral load-carrying capacity and appreciable ductility capacity provided by braced modules.