Experimental Study and In-depth Tensile Mechanism Analysis of Grouted Sleeve Lapping Conectors

Abstract

To study the failure modes, bearing capacity, ductility, and sleeve strain of grouted sleeve lapping connectors, 36 specimens were tested under uniaxial tensile load. The test results show that the sleeves are under longitudinal tension at the beginning, which changes to longitudinal compression in the late stage of loading, and the changing load increases gradually with the lap length. The force transmission path and mechanical mechanism of the connectors are analyzed. The distribution and development process of longitudinal sleeve stress is analyzed based on the constitutive model stress, and it is found that the sleeve changes from longitudinal tension to longitudinal compression at the late loading stage, which is consistent with the test results. Based on the test, the calculation formulas of the ultimate bond strength and critical lap length of the grouted sleeve lapping connector are proposed. The research results lay a theoretical foundation for the application of grouted sleeve lapping connectors.

Mechanical Test of Sleeve Grouted Lapping Connectors under Uniaxial Tension and High-Stress Repeated Tension and Compression Loading

“…The stress mechanism of the APC connector under tension was reported prev [23]. The sleeve was under axial tension in the initial stage of loading and axial com sion in the later stage of loading.…”

“…Outward force of the steel bar Inward force of the sleeve Outward force of the sleeve of the steel bar Comparative tests on the mechanical properties of grouted splice connectors and APC connectors were conducted by Yu et al [24]; it was shown that the constraint on the grouting material of an APC connector was stronger than that of a grouted splice connector, and the mechanical properties of the APC connector were better than those of the grouted splice connector. The APC connectors have mainly been studied using uniaxial tension tests [23,25] to determine the bearing capacity, load-displacement curves, and hoop and longitudinal strains of the sleeves. Meanwhile, the ductility, residual deformation, and hoop and longitudinal strain of the APC connector under high-stress repeated tension and compression loads have largely gone uninvestigated.…”

“…2022, 12, x FOR PEER REVIEW 3 of 24 way, the tensile load of the sleeve is small. Furthermore, the stress mechanism of the grouted sleeve lapping connector was studied in the literature [23]. The results showed that the sleeve was longitudinally stretched at the initial stage of loading, while the sleeve was longitudinally compressed in the late period of the loading process.…”

Analysis of the Mechanical Performance of Sleeve Considering the Different Distributions of Grouting Defects

“…Under the premise of full grouting, the prefabricated concrete beam connected by sleeve grouting can meet the requirements of bearing capacity and ductility. Yu et al [20] carried out tensile tests on 36 joints to study the stress mechanism of steel sleeve grouting lap joints, fitted the formula of joint ultimate bond strength, and proposed the formula of sleeve critical lap length.…”