Mechanical Performance of Reinforced Sleeve Connection of Prefabricated Concrete Structure and Optimization Design of Its Joints

Abstract

As a new type of building structure, prefabricated concrete structure has the advantages of fast construction speed, easy quality control, environmental protection and energy saving, and this building structure form has been widely used in many countries and regions. As one of the important connection methods, the steel sleeve connection is often used in prefabricated concrete structures because of its simple, fast and convenient construction characteristics. However, at present, there are still relatively few studies on the mechanical performance of steel sleeve connections and the optimal design of their joints. The purpose of this paper is to conduct an in-depth study and analysis of the mechanical performance of the reinforcement sleeve connection and the optimal design of its joints in prefabricated concrete structures.

Existing studies have shown that the mechanical properties of rebar sleeve connections are affected by a variety of factors, including the diameter of the rebar, the material of the sleeve, the connection method and the loading conditions. Under different loading conditions, the load-bearing capacity of the reinforcing bar sleeve connection exhibits obvious changes. It was found that in the tests, the load-strain curves of the specimens showed a monotonically increasing trend before the yielding load. Specifically, the yield load of specimen 1 was 183.0 kN, and the strain distribution in the reinforcement sleeve showed different characteristics after reaching this load. The test data showed that the maximum strains in the longitudinal direction of specimen A4, in the circumferential direction of A4, in the longitudinal direction of B4 and in the longitudinal direction of C4 were 1832 × 10−6, −512 × 10−6, 1780 × 10−6 and 1795 × 10−6, respectively. The results showed that the maximum position in the central part of the socket had already begun to yield when the specimen reached the ultimate load. This indicates that the reinforcing sleeve connection exhibits some plastic deformation capacity under high loading conditions. It is shown that the ductility coefficient of the node decreases instead with the increase of reinforcement rate at the beam end. This is mainly due to the fact that the increase in reinforcement rate leads to an increase in yield displacement at the beam end, which in turn affects the ductility performance of the node. These conclusions provide an important reference and guidance for the practical application of assembled concrete structures, which helps to optimize the design and improve the overall performance and safety of the structure.