Inter-Module Connections and Global Structural Behavior of Modular Steel Buildings: A Review

Abstract

Modular steel buildings are mainly constructed through factory prefabrication and on-site assembly. Their global structural performance is governed to a large extent by inter-module connections. Existing studies have shown that local nonlinear behaviors in connections, such as gap closure, frictional slip, semi-rigid rotation, and cyclic degradation, can be amplified into global structural effects through load-path reconfiguration and deformation compatibility. These effects include the redistribution of inter-story drift, the accumulation of residual deformation, and the formation of weak stories. As a result, they can influence seismic and wind-resistant design outcomes as well as structural robustness assessment. This paper reviews the structural forms and load-transfer mechanisms of inter-module connections in modular steel buildings. Experimental and numerical evidence on global structural behavior is systematically summarized. A performance evaluation framework oriented toward global response is then outlined, together with approaches for describing system-level coupling effects. The development of equivalent connection modeling and global analysis methods is also reviewed. Finally, research prospects are discussed from the perspectives of high-rise development, performance-based design, reparability, and robustness. The study aims to provide reference for engineering design and standardized application of modular steel buildings.