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Abstract In the pursuit of cost reduction and enhanced construction efficiency in the mechanical connection of reinforcing bars within precast assembled concrete structures, a novel-reinforcing bar connection joint is introduced. This innovative solution entails the utilization of 40Cr alloy steel tubing and the implementation of a hot forging high-precision rolling process to fabricate a series of new rebar joint specimens. Through unidirectional tensile testing, the failure modes of the specimens and the variations in load–displacement curves were meticulously analyzed. The investigation delved into the intricacies of the joint connection mechanism, scrutinizing the influence of three pivotal structural design parameters—namely the embedded length of the rebar, the sleeve thickness, and the clamp thickness—on the ultimate bearing capacity of the joint. The findings indicate that an embedded rebar length ranging from 1.5 to 1.75 times the nominal rebar diameter ensures a tensile strength ratio of the joint to the standard rebar tensile strength not less than 1.1. Notably, the sleeve thickness emerged as a significant factor impacting connection performance, while the clamp thickness exhibited negligible effects on specimen performance. Furthermore, an augmented internal thread angle was found to enhance shear resistance. The optimal design parameters encompass an outer sleeve diameter of 78 mm, a large end clamp diameter of 65 mm, and an internal thread angle of 60°. The proposed single taper sleeve locking-type joint, characterized by a rational structural design, aligns with the stipulations of Grade I joints outlined in the industry standard JG/J 107–2016. This novel joint design is well-suited for the mechanical connection of large-diameter rebars, offering a promising avenue for advancing construction practices in precast assembled concrete structures.
Li et al. (Wed,) studied this question.