A friction bolt is a type of rock bolt commonly used in ground support applications in mining, tunneling, and civil engineering. It is designed to provide reinforcement and stability in rock structures by anchoring unstable rock formations and preventing potential collapses or failures.

Here's how a friction bolt works:

Design: A friction bolt consists of a high-strength steel tube, typically around 1.5 to 2.0 meters in length, with longitudinal slots or splits along its length. These splits allow the tube to compress radially when inserted into a drilled hole.

Installation: The friction bolt is installed by inserting it into a pre-drilled hole in the rock or excavation face. As the friction bolt is pushed into the hole, the rock's radial pressure causes the tube to compress, exerting outward pressure against the walls of the hole.

Anchoring: Once fully inserted, the friction bolt locks itself into place within the hole due to the radial pressure exerted by the compressed tube. This creates frictional resistance between the friction bolt and the surrounding rock mass, anchoring the unstable rock formation and providing reinforcement.

Support: The friction bolt stabilizes the rock mass by redistributing stresses and increasing its overall strength. It helps prevent potential collapses, rockfalls, or other instability events by providing support and containment.

Compatibility: Friction bolts are often used in conjunction with other ground support systems such as mesh, shotcrete, or cable bolts to provide comprehensive reinforcement and stability in challenging geological conditions.

Friction bolts are valued for their simplicity, reliability, and ease of installation. They are particularly useful in ground conditions where other types of rock bolts may be less effective, such as in fractured or unstable rock formations. Friction bolts offers an efficient and cost-effective solution for ground support in mining, tunneling, and civil engineering projects.