The Influence of Inter-Connections Characteristics on the Lateral Performance of Braced-Frame Modular Steel Buildings

Document Type : Regular Paper


Faculty of Civil Engineering, Semnan University, Semnan, Iran


The use of pre-fabricated modular units for the construction of mid to high-rise buildings has been promoted recently. The modular units are fabricated in a factory and then transported to the construction site to form a structure using inter-connections. The inter-connection is unique to modular buildings, playing a critical role in their structural performance. Despite the increasing popularity of modular construction, there are relatively few published studies considering the influence of inter-connection’s behaviour on the lateral performance of braced-frame modular buildings. The inter-connections’ rigidity has an influence on the modular buildings’ stiffness. Hence, it is required to investigate their effect on the seismic performance of braced-frame modular buildings. This study aims to investigate the effect of inter-connections’ properties on the lateral performance of braced modular frames through nonlinear static analysis. To that end, three frames of four, eight and twelve storeys, are assumed for the required analysis. Different inter-connections having various stiffness properties are considered for the nonlinear static analysis. Three performance levels are considered and the responses of considered structures at these levels are evaluated and compared for different properties of inter-connections. The obtained responses indicate that the decrease of inter-connections’ stiffness leads to reduction of the lateral capacity. The results indicate that the decrease of inter-connection stiffness can increase the period of the structures up to 10.35%., 5.35% and 3.63% in 4-, 8- and 12-storey buildings. Moreover, the nonlinear analysis indicate that the increase of inter-connection flexibility reduces the base shear by 1.9%.

Graphical Abstract

The Influence of Inter-Connections Characteristics on the Lateral Performance of Braced-Frame Modular Steel Buildings


  • Lateral behaviour of braced-frame corner-supported modular steel buildings is investigated.
  • Pushover analysis is conducted to scrutinise the effect of inter-modular connection’s stiffness on the lateral responses of corner-supported braced frame modular steel buildings.
  • The influence of inter-connection’s stiffness on the period of these structures is investigated.
  • Pushover curves, shear and displacement distribution are compared as the result of variation of inter-connection’s mechanical properties.


Main Subjects

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