Application of Anchor Support Technology in Geological Conditions

Anchor support, as a proactive support technology, accounts for an increasing proportion of roadway support in China and even worldwide. Its easy and quick construction, simple construction method, good support effect, lighter labor intensity and better adaptability have been widely recognized. And with the development of anchor support apparatus, it has been more widely used in shaft mining practice.

When the roadway construction is carried out within the broken surrounding rock, the multiple damages to the coal rock body should be minimized. The digging process is suitable for mechanized operation. The construction of anchor holes should adopt the rotary cutting process to avoid the impact and vibration on the coal rock body as much as possible. When formulating countermeasures or modifying the design scheme for anchor support of roadway within the broken coal rock body, in addition to narrowing the inter-row spacing of anchor rods or anchor cables according to the specific conditions, the following technologies can be considered.

High-strength full-length anchor support technology: 

The anchor force of high-strength full-length anchor is distributed over the entire length of the rod body, avoiding the anchor force of end-anchor anchors from concentrating on the surrounding surrounding rock. The supporting effect of high strength full-length anchors is several times or even more than ten times that of ordinary end anchors with the same rod diameter. There is basically no gap in the hole of full-length anchors, and the rod body and anchoring agent are combined with the surrounding rock as a whole, which greatly improves the bearing capacity of the anchors. The use of high-strength full-length anchoring anchors can provide greater initial anchoring force and anchoring force, give full play to the restraining effect and shear-resistant effect of the anchor on the coal rock body, and improve the integrity and load-bearing capacity of the surrounding rock.

The use of widened and thickened W steel belt as a combination member: 

The anchor net and beam combination support form is conducive to the role of the anchoring balance arch, which can make the support members such as anchor rods, nets and beams (belts) form a support whole, improve the integrity of the surrounding rock, prevent the loosening of the rock around the anchor rods from affecting the support role of the anchor rods, and make the support system have a high degree of safety through the role of the beams, to prevent the sudden topping accidents. Reinforced ladder beam belongs to line contact: W steel belt belongs to face contact, and has high strength, high rigidity and large roof protection area. In the tunnel of broken coal rock body, wide and thick type W steel belt should be used instead of steel ladder beam, fully utilizing the advantages of W steel belt, ensuring the surface support strength, and the support effect will be better.