State-of-the-art review and investigation of structural stability in multi-story modular buildings

Prefabricated 3D modules are widely adopted in building construction for better quality, lower demand on labor and construction space, faster construction, and less emission. Various types of modular structures and connections have been tested and are commercially available. A large number of actual applications demonstrate that the structural system of a modular building can be flexibly organized to suit for the topmost utility architecturally. However, in terms of the stability of the structural system, the role of prefabricated modules widely varies. A systematic summary and categorization of different structural stability systems and layout patterns, especially in multi-story modular buildings where load sharing and transfer between the units are necessary, has yet to be made. This paper provides a state-of-the-art review which focuses on four major structural aspects, e.g., module connection, individual module structure, layout pattern, and additional stability unit. Recommended combinations of structural parts of the system are provided. Nonlinear static or pushover analysis is carried out with the numerical model based on available experimental data to demonstrate the roles of individual modules and additional stability units on system stability. A rating procedure for the modular structural system is proposed to briefly evaluate several aspects of the multi-story modular building structures. Trends in design and usage of modular structure systems are presented using examples of 20 unique applications.