Theoretical and FEA study on shear performance of novel shear connectors

Abstract

Shear connectors are essential components for force transfer in composite beams. Compared to conventional welded-bolt connectors, bolted shear connectors offer the advantage of easy removal. However, traditional bolted connectors for steel-concrete composite beams feature threads on the contact surface, reducing the shear cross-sectional area of the bolts. To address this limitation, this paper proposes a novel type of friction-clamping bolt connector, referred to as Connecting Lock Combination Bolts (CLCB¹). The finite element software ABAQUS was used to develop an analytical model for the CLCB, and a comparative analysis was conducted with traditional connectors. The static performance of the new shear connectors was evaluated, and a shear load capacity formula applicable to CLCB connectors was derived. Additionally, linear and exponential functions were employed to fit the load-slip curve of the CLCB connectors. The results indicate that the shear load capacity of CLCB connectors exceeds that of conventional bolted connectors. Moreover, the bolt diameter and concrete strength are the primary factors influencing the ultimate shear load capacity and stiffness of CLCB connectors. The preload on the bolts enhances the shear stiffness, while parameters such as bolt hole clearance, the height of the lower nutted rod, and the clearance between the upper and lower bolt rods are crucial in ensuring the proper functioning of CLCB connectors. Furthermore, the shear capacity formula provides an accurate prediction of CLCB connector performance with an error margin of less than 6 %, and the load-slip curve model effectively illustrates the load-slip relationship under shear.