Hollow anchor rods come in various materials, all closely related to their construction factors. Here are the specific materials for hollow anchors:

Reinforcement or wire rope grout anchors. These are anchors that use cement砂浆 as the bonding agent between the anchor and the surrounding rock.

2. Wooden anchors. There are two commonly used types of wooden anchors: compressed wooden anchors and regular wooden anchors.

3. Resin Anchor Rods. Using resin as the bonding agent for anchor rods is more expensive.

4. Double Quick Cement Anchor Rods. These anchor rods are made by mixing high-quality finished cement with double quick cement in a specific ratio. They feature rapid hardening and early strength.

5. Friction Bored Anchor. It is a type of anchor bolt with certain friction. This anchor bolt boasts reliable anchoring, high initial anchor force, simple installation, and its long-term anchoring force increases with the movement of the surrounding rock.

6. Quick-hardening expansive cement anchor rods are manufactured by adding admixtures to ordinary Portland cement or slag Portland cement. They feature rapid setting, early strength, expansion, and water-reducing properties.

7. Wedge-type metal anchor rod. This type of anchor rod was once one of the most widely used. Due to its simple processing, ease of installation, and certain anchoring force, it is still in use within a certain range.