The Construction Process of Rock Bolt Support (5 Key Steps)
Step 1: Drilling
- Perform drilling strictly according to design specifications, controlling the position, depth, inclination, and diameter of the holes.
- Use surveying instruments for positioning to ensure accurate hole placement.
- Choose appropriate drilling methods and drill bits based on geological conditions to ensure drilling quality.
- Observe the hole wall condition during drilling to prevent hole collapse and drill jamming.
Step 2: Hole Cleaning
- After drilling, promptly clean the hole to remove rock powder, soil, and other debris.
- Use high-pressure air or water flushing to ensure the hole is clean.
- Measure the depth of the hole after cleaning to ensure it meets design requirements.
Step 3: Bolt Installation
- Inspect the bolts before installation to ensure they are free of damage and corrosion.
- Slowly insert the bolts into the hole to avoid damaging the bolts or the hole wall.
- Ensure the insertion depth of the bolt meets design specifications, typically requiring the exposed length of the bolt to not exceed 10% of the design length.
Step 4: Grouting
- Prepare the grouting material according to design specifications, strictly controlling the water-cement ratio and the amount of additives.
- Use appropriate grouting methods, such as pressure grouting or secondary grouting, to ensure grouting quality.
- Control grouting pressure and flow during the process to avoid excessive pressure causing ground uplift or hole wall collapse.
- Inspect the grouting effect after completion. If grouting is found to be insufficient or there is leakage, perform supplementary grouting promptly.
Step 5: Tensioning and Locking
- Once the grout has reached the required strength as per design, proceed with bolt tensioning and locking.
- Ensure the tensioning equipment is calibrated for accuracy and reliability.
- Perform tensioning following the specified sequence and force requirements, applying load gradually without exceeding the design tension.
- After tensioning, lock the bolt immediately, ensuring the locking force meets design standards.