Shear behaviour of a novel self-locking inter-module connection with spring-loaded plunger latches

One of the greatest challenges in designing modular buildings lies in the inter-module connection, which is distinct from conventional structural systems. The role it plays is essential not only in determining the structural responses of stacked modules but also in enhancing the efficiency of on-site assembly. Among many existing designs, the proposed self-locking inter-module connection emerges as a promising solution, offering a balanced integration of functionality and workability. This study aims to explore the structural behaviour of the self-locking connection under shear through both experimental and numerical approaches, and to contribute valuable insights into the safe design of multi-storey modular buildings subject to lateral loads that may be generated from winds, seismics, and localised damages. First, a total of six full-scale specimens with various sleeve configurations were tested in a double-shear arrangement to identify the typical failure mode, which was found to be the fracture of protruded sleeve for all the tested specimens. By calibrating the ductile fracture simulation, a finite element model was established and proven reliable in predicting the structural responses of the connection under shear. This model was then used to evaluate the full-range damage evolution of critical components, as well as serving as an effective means to explore the effects of parameters. Finally, a simplified calculation method was developed by examining the relationship between the effective area for shear and the aspect ratio of the sleeve section, offering a practical solution for routine engineering designs.