Embedded steel column-to-foundation connection for a modular structural system

• Embedded column-to-foundation connection was proposed for a modular structure.
• Effect of the embedment depth on the proposed connection behavior was investigated.
• Pull-out failure occurred when the embedment depth is not sufficient.
• Ductile column yielding was observed when the embedment depth is sufficient.
• A design equation to determine the minimum depth was proposed.

Pre-made modular units permit rapid and economical construction and are increasingly used where repetitive units are required. The assembled building must behave as a single structure to effectively transfer the forces and moments developed by gravity and lateral loads. For this, individual modular units must be properly connected to each other. Therefore, evaluation of the behavior of connections used in modular construction is crucial. This study proposes an embedded steel column-to-foundation connection for modular structural systems and evaluates the behavior of the proposed connection. Experiments were performed to investigate the effect of the column embedment depth, the shape of the column end plate, and shear studs in the embedded region of the column on the connection behavior. Further, three dimensional nonlinear finite element analyses were conducted for each test specimen to demonstrate the in-depth behavior of the connection. Finally, a design equation for the proposed connection was proposed.