Effect of inter-module connection properties on structural sway of high-rise modular buildings

Abstract

The modular steel building is a rapidly evolving prefabricated structural system, consisting of discrete volumetric modules assembled with inter-module connections. Despite numerous studies on the design optimization of inter-module connections, research on the development of realistic connection models and the correlation between connection properties and the overall structural behavior is relatively scarce. This paper introduces a multiple-spring inter-module connection model and supplies detailed property calculations of different load transfer components. The model can effectively simulate different stiffness and strength levels at inter-module connections and predict relative dislocations between assembled modules. The model is then applied to analyze the structural sway of modular buildings under seismic loads. Influences of connection modelling methods and the real connecting abilities on structural sway responses are investigated through comparative analysis of connection and module drift deformations when using conventional pin or rigid constraint connection models and the proposed realistic multiple spring model. Results indicate that simplified pin or rigid constraints cannot accurately represent the actual load transfer mechanisms at inter-module connections. The horizontal link determines the composition extent of horizontally assembled columns and modules. The horizontal shear resistance is closely related to column loads and follows the downwardly increased mode, which induces different structural sway and module drift levels in modular buildings.