Lateral behaviour of modular steel building with simplified models of new inter-module connections

For the structural response estimations of modular steel buildings, the shear, axial and moment-rotation behaviours of the inter-module connections are normally simplified and input into the overall numerical model. While linear models have traditionally been used for the simplification, they do not reflect the true non-linear responses of the connections. Through recent studies, improved models have been developed for the structural behaviours of the newly proposed post-tensioned (PT) and interlocking (IL) inter-module connections (IMCs). In this paper, the newly proposed models are implemented in the numerical simulation of a selected modular steel building. The effect of the inter-module connections on the global building responses to simulated time-varying wind loads and earthquake ground accelerations is examined. Hence, the application of the new simplified models is demonstrated, while the performances of the building incorporating the two different connections are compared. The results demonstrate that the new simplified models are well-suited for use in global numerical simulations. The analytical basis of the models allows application to varied connection geometries, and the more accurate connection behaviours contribute to an improved understanding of the global building responses. Inter-storey drift ratio limits, for example, which are not yet defined for modular buildings, are proposed based on the simplified connection behaviours.