Experimental Study on Mechanical Properties of Half-Grouted Sleeve Connections with Grouted Defects

Abstract

Prefabricated concrete structures are driving the development of green buildings, and the connection between prefabricated components is the main factor affecting the safety performance of these structures. Grouted sleeve technology can effectively improve the safety performance of precast component connections. In the process of grouting operation, the grouted sleeves are affected by the construction environment and often have various defects. In this work, to study the influence of defects on the mechanical properties of half-grouted steel sleeve connections, 33 specimens (10 groups of defective specimens (three in each group) and 1 standard group) were prepared and subjected to uniaxial tensile tests. The failure modes, load–displacement curves, stress distribution, and other mechanical properties of the specimens were studied. Sleeves with different defects were simulated, and the simulation results were compared with the experimental results. The experimental results showed that the failure modes are rebar fracture and rebar pull-out. In the strengthening stage, the specimens exhibited a large slip. The critical length for failure mode transition was 2.5 d (defect length). The middle defects and uniform defects had the most unfavorable effect on the ultimate bearing capacity of the specimens. The stress transfer was blocked in specimens with end and middle defects. The numerical simulation results were consistent with the experimental results, thus verifying the accuracy and feasibility of the simulation method for practical applications.