Sinorock hollow anchor bars  have been widely applied in various engineering，at the same time，it has passed all tests.

Solve the problem that broken into a hole and quick make a  hole safely in the rock mass is the important achievement of the construction, the construction process in strict accordance with the "advance guard, short excavation, weak blasting, spray anchor, frequently measure" principle, slowly but surely, step-by-step, the key is to ensure that the drainage hole construction progress and safety, but also should pay attention to the following items:

1 Using the hollow anchor bar to lead consolidation grouting bolt, should be in a circular steel arch after installation, shotcrete before implementation, to ensure that the cycle of blasting cement mortar has certain strength, give full play to the effect of consolidation grouting.

2 Consolidation grouting in the crown area form a thin layer of crust and the upper or the grit rock., therefore, must be strictly controlled blasting parameters and circulating footage, lest because of blasting vibration and circulating footage is too big, lead to the crown of thin shell break fast and collapsed.

3 Deep drain with eccentric bit drilling, casing carefully follow up the process, when meet a large rock, casing never aggressive follow up when the difficult, forced the casing head may occur due to eccentric bit did not break rock, causes for casing deflection rock stuck can't pull out, resulting in the waste hole and casing damage, at this time eccentric bit should be into ordinary impacter and sweeping hole drilling and concrete, to be by eccentric bit chunks of rock and then changed to continue to make hole.