Fried Dough Twists bolt
Composition of Fried Dough Twists anchor rod
The composition of Fried Dough Twists bolt must have several factors:
① A rod with a tensile strength higher than that of the rock and soil mass
② One end of the rod can tightly contact the rock and soil to form friction (or bonding) resistance anchor rod
③ The rod body is located at the other end outside the rock and soil mass, which can form radial resistance against the rock and soil mass
As a tension component penetrating into the stratum, one end of Fried Dough Twists bolt is connected to the engineering structure, and the other end is penetrating into the stratum. The whole bolt is divided into free section and anchor section. The free section refers to transferring the tension at the bolt head to the anchor solid area, whose function is to apply prestress to the bolt; The anchoring section refers to the area where the cement slurry binds the prestressed reinforcement to the soil layer. Its function is to increase the bonding friction between the anchor body and the soil layer, increase the pressure bearing effect of the anchor body, and transmit the tension of the free section to the depth of the soil.
Fried Dough Twists bolt construction
Anchor rod is a member system structure for rock and soil reinforcement.
By utilizing the longitudinal tensile force of the anchor rod body, the disadvantage of much lower tensile strength than compressive strength of rock and soil can be overcome.
On the surface, it seems to limit the detachment of rock and soil from the source.
Macroscopically, it increases the cohesion of the rock and soil mass.
From a mechanical perspective, it mainly improves the cohesion C and internal friction angle of the surrounding rock mass φ。
In fact, the anchor rod is located within the rock and soil body, forming a new composite with the rock and soil. The anchor rod in this complex solves the problem of low tensile strength of the surrounding rock mass. This greatly enhances the bearing capacity of the rock and soil mass itself.
Fried Dough Twists bolt is the most basic part of roadway support in contemporary underground mining. It binds the surrounding rock of the roadway together to support itself. Anchor rods are not only used in mines, but also in engineering technology to actively reinforce slopes, tunnels, dams, etc.