Modular steel construction (MSC) exhibits widespread potential applications in civil engineering due to its quickness and standardization. Inter-module connection is a crucial issue for the structural behavior of MSC. A new fully prefabricated liftable connection (FPLC) for MSC was proposed in this paper. Axial compressive loading tests of the FPLC were conducted. Followed, an elaborate finite element model (FEM) for the FPLC was developed. Validation of the FEM by three test specimens confirmed that the developed FEM was capable of predicting the load bearing capacity and failure mode of the FPLC. Furthermore, the validated FEM was used to conduct a series of simulations on the tensile performance of the FPLC to perform an in-depth investigation on the influence of the thickness of the gusset plate (tp), thickness of the inner plate (ts), strength grade of the column (Sc), pretension load of the long stay bolt (P), diameter of the long stay bolt (d) and thickness of the modular column (tc). The influence of these parameters on the ultimate axial tensile resistance of the FPLC and damage indices, including the rupture index (RI) and plastic equivalent strain (PEEQ), along the defined critical lines of all specimens was determined and is reported and discussed in detail to reveal the damage mechanism of the connection under tensile force. Finally, a theoretical model for predicting the ultimate axial tensile resistance of the FPLC was proposed. The capability of the formulas to predict the axial ultimate tensile resistance of the FPLC was checked through validation against a total of 16 numerical results. The present study provides an engineering practical connection for MSC and important guidance for the design of the connection.
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