Anchor bolt combines drilling, installing, grouting and anchoring together, is a well-designed system according to different site

conditions, geological conditions and usage conditions, with high-efficient, reliable and convenient features, which ensures its anchoring

effect in different and complex stratum. There are some points in anchor bolt design:
1. Design problem.

Before anchor bolt’s support, geomechanics evaluation work should be done at first, which includes field investigation of geological

conditions, mechanical property measurement, stress measurement and pull-out test of roadway surrounding rocks.

Based on specific geological conditions, different zones in same roadway, same coal seam and same mine should choose different supporting

forms and parameters.

2. Quality control.

During actual construction, to ensure installation qualified once and avoid exposure of anchor bolt too long, anchor bolt is usually

installed too deep, which reduces anchor bolt’s valid anchorage length.

The reinforcement measure mainly depends on roadway’s deformation. And the second strength is usually greater than the first one.

3. Design procedure.

During the process of anchor bolt’s supporting design, procedure should be followed: surrounding rock classification, primary design,

monitoring analysis and optimization design to make sure design scientific and reasonable, support secure.

4. Supervision and monitor.

Establish supervising and monitoring system to control deformation of roadway surrounding rocks. Machines and tools should be tested on

time.

5. The primary principle of anchor bolt’s supporting design.

Roadway should adopt rectangular cross-section. The designed height and width should leave proper deformation under preconditions of

ventilation, transportation and pedestrian.

Choose anchor bolt and other supporting products with stable property, high technical content and proper standard.