Simplified structural behaviours of post-tensioned inter-module connection for modular buildings

When designing modular buildings, the structural behaviour of the inter-module connections (IMCs) must be simplified so they can be incorporated in the structural model. However, the existing models for the shear, axial and moment-rotation behaviour are limited, and further study is required to develop improved models. In this study, the shear, axial and moment-rotation behaviours of a post-tensioned IMC are investigated. A numerical model is developed and calibrated based on the shear behaviour obtained from experiments. Following the experiments, a simplified empirical model is proposed for the shear behaviour. The numerical model is then extended to determine the axial and moment-rotation behaviour. Simplified analytical models are derived and compared with the numerical results. Further, the numerical results are compared with the behaviour of other existing IMCs, for which experimental data are available in the literature. In this way, simplified models which can predict the shear, axial and moment-rotation behaviour of the post-tensioned IMC are developed. The developed simplified models can be used to predict the behaviour of modular structures with the newly proposed post-tensioned IMC. •Structural behaviours of the post-tensioned inter-module connection are studied•A numerical model is developed and calibrated from the experimental shear behaviour•A refined two stage empirical model is proposed for the shear behaviour•The numerical model is extended to study the axial and moment-rotation behaviour•Simplified analytical models are derived to predict the connection behaviour