Shear behaviour of post-tensioned inter-module connection for modular steel buildings

In modular steel buildings the inter-module connections are key to the successful site installation of modules and the overall structural behaviour of the assembled building. The existing connection details such as site welding typically require external access during site install, which is not always possible or practical. Post-tensioned bolted steel connections are an enticing solution because they minimise the requirement for site work, allowing for easier internal assembly. However, the existing shear forcedisplacement model for inter-module connections is inadequate, and the initial load-slip behaviour is not accurately predicted. In this study, a new post-tensioned bolted steel connection is proposed and the prototypes are manufactured. The shear force-displacement and load-slip behaviours are investigated experimentally. The proposed connection is shown to have good initial stiffness in shear, which can be well controlled by the parameters of preload and slip factor. In addition, numerical simulation is conducted and the influence of the preload and slip factor on the load-slip behaviour is investigated. An improved empirical model is developed, and its application is demonstrated for the proposed connection. (C) 2019 Elsevier Ltd. Ail rights reserved.