Rebar Mechanical Connection Technology

Rebar mechanical connection is a new technology, which is called” The Third Generation of Rebar Connection” after welding technology.

Frequently-used rebar mechanical connection technologies are as follows:

1. Rebar extrusion/stamping connection joint: it is formed by extruding coupler to plastic deformation to connect with rebar tight.

There are two forms: radial extrusion connection and axial extrusion connection. Because axial splice is inconvenient at the construction site and joint quality is not stable enough, it has not been promoted. But the radial extrusion connection has promoted widely. Now the extrusion joint used at projects are all radial extrusion connection. Due to its good quality, radial extrusion connection has being widely used in construction projects since the early 1990’s in China.

2. Taper thread connection joint: it is formed by connecting special taper thread coupler and rebar tight. The birth of tapered thread connection technology overcomes the deficiencies of extrusion connection technology. The taper thread head could be prefabricated completely, and the duration of on-site connection is short, only need torque wrench to operate on-site. Without moving machine and pulling wire, it is highly praised by many construction projects. But taper thread connection is not stable enough. Because the diameter of Bottom Thread is smaller than the Base Circle Diameter of rebar, the joint strength has been weakened, and only reaches 85-95% tensile strength of parent metal.

3. Parallel thread connection joint: it is the most popular in the 1990s, the joint is stable, reliable and with high connection strength. It can rival extrusion/stamping connection joint, also with the characteristic of taper thread connection joint: convenience and fast speed. So the emergence of this connection technology has brought a qualitative leap to the rebar connection technology. At present, parallel thread connection technology mainly includes two kinds: upsetting parallel connection joint and rolling parallel thread connection joint. Both technologies adopt different processing methods to enhance the strength of threaded rebar end, and reach the same strength as parent metal.

Source: http://zhidao.baidu.com/link?url=bZEMi0LTJ1chGO8ByKPS-uoITjEN42mI3G9CbB4NUU4nZ-h3xAfMr16sUU5fd97iqZlRH6ytFFDA4JcHDeCrm_

Edit: OCEPO