Structure of Prestressed Rock/Soil Anchor System
Prestressed rock/soil anchor system is an important technology for geotechnical engineering reinforcement in recent years.
The prestressed rock/soil anchor system consists of three parts: bond section, free section, and outer section. The steel strands of the bond section are bare strands and are formed by binding the guide cap, the spacers, and the grouting pipe sheath with iron wires. The free section of the steel strand is anti-corrosion type, and the length of each strand is a Φ22 plastic pipe or a PE steel strand produced by the manufacturer. A grouting pipe sheath is provided for each meter of the strand and tied with iron wires. The outer section is composed of steel bearing plates and anchor heads.
The functions of each component in the rock/soil anchor system are as follows:
- The guide cap is at the front end of the strands, which can prevent the hole wall from being stuck when the strand is pushed.
- The spacer evenly distributes the steel strands in the holes and makes the steel strands in the middle of the holes to ensure that each steel strand is evenly held by the mortar to provide anchoring force. And leave a certain protective layer of mortar outside the steel strand to prevent corrosion of the steel strand in the bond section.
- The grouting pipe sheath can prevent the grouting pipe from collapsing during lashing, and the grouting pipe can be drawn out freely during the grouting process.
- The plastic pipe outside the free section of the steel strand can be isolated from the mortar. The steel strand can be stretched freely during tension, and the stress can be adjusted in the free section to avoid stress concentration. Plastic guiding pipe has an anti-corrosion function.
- The steel bearing plate of the outer section can transfer stress to the concrete during tension.
- The working anchorage is composed of an anchor head and wedges, which together play a role in clamping the steel strand to ensure that the prestress of the steel strand after tension is not lost, and the rock/soil anchor system is in a normal working state.
- The mortar injected into the hole is bonded with the hole wall and the steel strand in the bond section to provide anchoring force and at the same time prevent corrosion of the entire length of the steel strand.