Capacity and failure mode prediction of long-bolted connection in panelized modular houses

This study investigates the structural performance of a newly proposed bolted connection for panelized modular structures, using high-strength bolts and extended plates, aimed at addressing Canada’s housing shortage, particularly in remote areas. A finite element model (FEM) was developed and validated against experimental data to evaluate the connection’s behaviour. A parametric study of 240 FEMs was conducted on unstiffened connections, examining the effects of extended plate thickness, bolt configuration, and bolt diameter. Results show these parameters significantly affect moment capacity, failure mode, and inelastic rotational behaviour. The bolt arrangement and quantity fostered a “strong column–weak beam” mechanism, enabling plastic hinging in the beam. Additionally, bolt diameter and plate thickness were found to govern ultimate rotation capacity and failure modes. To support practical application, design charts and a mathematical equation based on genetic regression were developed to predict ultimate capacity, thereby streamlining the design process and reducing trial iterations.