Cement grouting reinforcement connector

Abstract

A cement grouting reinforcement connector comprises connecting reinforcements, a connecting sleeve and cement mortar; and the abutted ends of the two connecting reinforcements are combined into a connection body by the connecting sleeve and hardened cement mortar full of the gap of the connecting sleeve. The outer surface of the connecting sleeve and the inner wall of the sleeve are respectively provided with continuous or discontinuous grooves or bosses. The connector has the following advantages that a seamless steel pipe, a forged steel cylinder or a stamped steel cylinder which has high strength and stable property is used as the connecting sleeve, and the grooves in the outer surface of the connecting sleeve and the bosses on the wall of the inner holes are formed by using a rolling-pressing or rotary-pressing method. The raw material dosage is greatly reduced by the improvements of the structure and the material of the sleeve; and the cutting processing amount is greatly reduced by the improvement of the machining technique of the sleeve, and therefore, the cost of the sleeve is reduced and the production efficiency is increased; and the economic and technical indexes of the connector exceed those of the known cement grouting reinforcement connectors.

Description

technical field [0001] The invention relates to a joint applied to the ribbed steel bar connection of prefabricated concrete structure prefabricated components. The joint is superior to the existing cement grouting steel bar joint in terms of structure, material consumption, manufacturing cost and the like. It can connect steel bars arranged vertically, horizontally or obliquely, so it can be widely used in prefabricated structural systems. Background technique [0002] In the construction of modern prefabricated concrete structures, the stressed steel bars of prefabricated components are mainly connected by cement grouting connection method. Cement grouting steel bar joint is composed of connecting sleeve, non-shrinking high-strength cement mortar and ribbed steel bars connected at both ends of the sleeve. The principle is: pour non-shrinking high-strength cement mortar into the connecting sleeve, fill the sleeve and The gap between the steel bars, after the cement mortar ...

AI Technical Summary

Problems solved by technology

Its disadvantages: First, the external dimensions of the connecting sleeve are large. In the building structure, when the thickness of the concrete cover and the spacing of the steel bars meet the requirements of the design specifications, the external dimensions of the components are relatively large, which not only increases the project cost per unit area, but also The usable area of ​​the building is reduced; the second is that the connecting sleeve is made of casting. To ensure that the material strength and processing quality of the stressed structural part meet the design requirements, the requirements for its casting process and quality control are very high. High cost, difficult to promote and use in large quantities

Third, the outer surface of the sleeve is smooth, so the anchoring force between the outer surface of the sleeve and the concrete is much lower than that between the ribbed steel bar and the concrete. When the steel bar of the prefabricated component is subjected to a large tensile load At the same time, the grouting joint sleeve whose length is several times the diameter of the steel bar will also be deformed to a certain extent. The anchoring force between the smooth outer surface of the sleeve and the concrete is small, which cannot limit the deformation of the sleeve, and the sleeve will be in contact with the surrounding concrete. Detachment, even cracks in the concrete, reducing the durability of the concrete structure, or forming a safety hazard

[0004] In recent years, a cylindrical grouting joint different from the traditional cement grouting joint has appeared. The joint is made of round steel or steel pipe. One end is grouted and the other end is threaded, so that the overall size of the joint is significantly reduced, especially the length. , the concrete section affected by the joint with relatively poor anchoring effect is reduced, and the integrity of the concrete member is improved, but the joint still has a smooth surface that is more than 6 times the diameter of the steel bar, and the anchorage force of the sleeve in the concrete Insufficient phenomenon has not been fundamentally resolved

This deficiency is particularly prominent for connecting sleeves with larger steel bar diameters

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