Using a 39mm split set for mine support involves several steps and considerations to ensure the safety and stability of underground excavations. Split sets are commonly used in mining as a dynamic ground support system to reinforce tunnel walls, particularly in areas with poor ground conditions. Here’s a detailed guide on how to effectively use 39mm split sets for mine support:

Understanding Split Sets:

Split sets are cylindrical steel tubes with a longitudinal split along their length.

They are designed to provide support by gripping the surrounding rock when inserted into a predrilled hole.

Preparation:

Before installing split sets, conduct a thorough assessment of the ground conditions to determine the appropriate support system.

Ensure that all personnel involved in the installation are trained in handling and installing split sets safely.

Equipment and Materials:

Gather all the necessary equipment and materials, including split sets, drilling equipment (jumbos or handheld drills), rock bolts, resin cartridges, grout, and any required safety gear.

Drilling:

Drill holes into the rock at specified intervals and angles according to the engineering design and ground conditions.

The diameter and depth of the holes should match the specifications provided for the split sets being used.

Insertion of Split Sets:

Carefully insert the split sets into the drilled holes. It's important to ensure that the split is aligned with the direction of the anticipated load.

Use appropriate tools to drive the split set into the hole until it reaches the desired depth. This may require a pneumatic or hydraulic hammer.

Expansion:

Once the split set is in place, the internal stresses cause it to expand, pressing against the rock walls.

This expansion creates frictional resistance, anchoring the split set firmly within the surrounding rock mass.

Grouting (optional):

In some cases, grout may be injected into the annulus between the split set and the rock wall to further enhance stability.

Grouting helps fill any voids and provides additional support by bonding the split set to the surrounding rock.

Testing and Monitoring:

After installation, conduct tests to ensure that the split sets are providing the intended support.

Monitor the performance of the support system regularly, especially during excavation and blasting activities, to detect any signs of instability or failure.

Maintenance:

Implement a regular maintenance schedule to inspect and, if necessary, replace damaged or corroded split sets.

Keep records of installation dates, inspection results, and any maintenance or repairs conducted.

Safety Precautions:

Prioritize safety throughout the installation process by adhering to established safety protocols and using appropriate personal protective equipment.

Ensure that all personnel are aware of potential hazards and are trained in emergency procedures.

By following these steps and considering safety as a top priority, you can effectively use 39mm split sets for mine support, enhancing the stability of underground excavations and minimizing the risk of ground instability-related accidents.