A rock bolt is a large metal screw that helps hold rocks in place so they don’t fall during underground drilling. Rock bolt Anchoring helps keep the roof and walls firmly in place, preventing them from moving or collapsing. A resin capsule is a small, sealed tube or cartridge that contains two components: a resin (polymer) and a hardener (catalyst) separated inside the capsule. It’s mainly used in rock bolt anchoring and ground support in mining, tunnelling, and civil engineering.
How it works:
- Composition
- Outer shell: Usually made of thin, breakable plastic film.
- Inside: Two compartments. one with polyester or epoxy resin, the other with a catalyst (hardener) such as an organic peroxide.
- Installation
- The capsule is inserted into a drilled hole in the rock.
- A steel bolt or rebar is pushed (and rotated) into the hole.
- The bolt’s rotation breaks the capsule, mixing the resin and hardener.
- The mixture reacts and hardens (polymerizes) within a few minutes, bonding the bolt firmly to the rock.
- Function
The hardened resin transfers the load between the bolt and the surrounding rock, creating a secure, corrosion-resistant anchorage that supports rock stability in underground excavations.
- Common Types
- Fast-set capsules – for immediate load bearing (typically 30–60 seconds).
- Slow-set capsules – used in combination with fast-set ones for full-length anchorage.
- Applications
- Roof and wall support in underground mines and tunnels
- Stabilization of rock slopes and excavations
- Anchoring of structural bolts in concrete
Reference: Mine Mentor
