Seismic performance of full-scale modular steel frame: Components and joints

In this paper, the authors conducted full-scale seismic tests on a modular steel frame, monitoring strains in beams, columns, and grouted connections, and measuring deformations in the connections. The first accompanying paper analyzes and discusses the overall response of the frame. This paper further investigates the seismic performance of the components and connections tested in the frame. Compared to conventional T-shaped joint and cruciform joint tests, the use of realistic boundary conditions in the connections allows for a more accurate study of the cyclic response of grouted connections. The seismic responses of module beams and columns were analyzed. The hysteretic behavior, skeleton curves, and energy dissipation of the grouted connections were discussed. Based on this information, the plastic development sequence and failure mode of the frame were summarized. Results show that the components and connections exhibit good cyclic performance, deformation capacity, and energy dissipation. The plastic development sequence and failure mode of the frame are yielding of the module beams (drift ratio of 0.67% rad – 0.86% rad), yielding of the horizontal connection plates (0.8% rad), yielding of the column bases (0.81% rad – 0.99% rad), and yielding of the modular column bases (0.94% rad – 1.33% rad).