Dimensional requirements for joints

The size of reinforcement connection joint determines the thickness of reinforcement cover, so it will affect the durability of concrete structure. In addition, the size of connection joints also affects the spacing of reinforcement and the layout of reinforcement in construction. The influence of different reinforcement connection joint sizes is described as follows.

 

Binding and lapping:

The size of overlapping connection joint of overlapping bound reinforcement has a great impact on the spacing of reinforcement. In the area with dense reinforcement, it may also cause inconvenience to the layout of reinforcement. Especially for large-diameter thick reinforcement, overlapping connection may also cause greater construction difficulties.

 

Welded connections:

The size of welded connection is very small, which is basically the same as the overall reinforcement, so it will not affect the change of protective layer and make it difficult to arrange reinforcement. However, if the welding is also under construction on site, the operation remains unchanged, which makes it difficult to ensure the connection quality, so manual welding should be avoided as far as possible and the factory semi-automatic welding process should be realized as far as possible.

 

Mechanical connection:

The mechanical connection transmits force through the connecting sleeve, and the diameter of the sleeve is larger than that of the reinforcement, which will reduce the thickness of the protective layer and affect the durability of the concrete structure and the spacing of reinforcement in the component, especially the impact of squatting out reinforcement thread connection and sleeve grouting.

 

 

Economic requirements

Binding reinforcement，The overlapping connection of reinforcement is relatively simple. The fine outline is used to bind the reinforcement in the connection section. This construction is more economical, but the binding of reinforcement is labor-intensive and the labor conditions are poor. When high-strength reinforcement is used, the overlapping length of reinforcement is relatively large, which will lead to the increase of reinforcement consumption and reinforcement engineering price.

Welded reinforcement,Welding connection is economical, but it is also labor-consuming, time-consuming and poor labor conditions. The situation can be improved by avoiding manual welding and realizing industrialized semi braking or automatic welding process.

Mechanical connection,The higher price will increase the construction cost, but with the large-scale engineering application and large-scale nested production, the price has decreased a little in recent years, especially when the mechanical connection is used to catch up the reinforcement with large diameter, it may get a better economic effect