1.     The formation of the prestressed structure of the split set is conditional, and the anchor rod pre-tightening force is the key. Under the condition of large horizontal stress, the role of the anchor rod is to provide high prestress to the top plate in time to form a prestressed top plate, forming a pressure self-supporting structure.

2.     The high pre-tightening force anchor rod is designed to establish a pre-stressed roof. The existence of the pre-stressed roof protects the roof from horizontal stress to a certain extent, so that the roof rock layer is in a state of lateral compression to overcome the high level of stress on the roof. The impact of stability.

3.     The pre-tightening force of the split set can play the role of anchor rod active support, especially in the conditions of layered rock formations and broken surrounding rocks, increasing the pre-tightening force can change the nature of the surrounding rock, prevent the surrounding rock from being damaged, and keep the surrounding rock stable. Conducive to supporting the surrounding rock.

4.     The pre-tightening force of the split set has a decisive effect on the stability of the roof. When the pre-tightening force is large to a certain extent, the roof separation within and above the anchor rod length can be eliminated