Collapse resistance of floor system in steel modular structure

This paper numerically investigates the collapse performance of the floor system in a steel modular structure. The study includes the analysis of the load-deformation relationship and internal force evolution of the floor system under four interior module loss, two edge module loss, and one corner module loss. The collapse resistance of the floor system in the modular structure is compared with that of the frame structure. Additionally, the study investigates the effects of critical variables such as the axial resistance of horizontal connections, floor slab thickness, and module beam dimensions on the collapse performance of the modular structure. The findings reveal that the floor system demonstrates the highest robustness in four interior module loss, while its weakest performance is observed in the scenario of one corner module removal. The final displacement of the floor system in two edge module loss and one corner module loss is 1.4 times and 2.5 times respectively, compared to that of the four interior module loss scenario. Moreover, when the material consumptions of the modular structure and frame structure are the same, the robustness of the floor system in the steel modular structure is significantly lower than that of the steel frame structure. It should be noted that under certain circumstances, increasing the axial resistance of the horizontal connections may not have a remarkable impact on the robustness of the floor system in the modular structure. In situations of two edge module losses, reducing the slab thickness and beam depth leads to an increase in the axial force in the horizontal connections of the floor system.