Experimental Study on Seismic Performance of Corner-Supported Modular Steel Buildings

The corner-supported modular steel building is a new structural system composed of three-dimensional modules that are prefabricated in factories and assembled on site. Due to its different construction method and structural make-up from those of the traditional steel frame,the seismic performance of corner-supported modular steel structures is poorly understood. In this study,we assembled a two-story full-scale modular frame structure using vertical rotary inter-module connections and tested it under cyclic loading to investigate its mechanical behavior,such as the lateral bearing capacity,failure mode and strain distribution. The experimental results showed that such structures have good hysteretic performance,with the lower modular frame able to maintain sufficient bearing capacity up to an inter-story drift ratio of 0.04 rad,which satisfies the ductility requirement of the special moment frame specified in AISC 341-16. In addition,a penetrating crack occurred at the right end of the floor beam,but at the left end,plastic hinges formed at the flanges away from the cover plate. The inter-module connections were also able to transfer internal force without failure despite the opening. After the failure of the intra-connections in the lower frame,we conducted a push-over experiment and observed that the opening of the inter-module connection continued to increase accordingly. At the end of the experiment,the bearing capacity of the structure had exceeded the failure load,which indicated that this structure had residual bearing capacity. The performance of the inter-module connection should be given more significance due to the internal force redistribution in the connection region. © 2021, Editorial Board of Journal of Tianjin University(Science and Technology). All right reserved.