Installation requirements for split set:

According to the reinforced mortar anchor rod, it is generally divided into two types of construction techniques: first grouting and then anchoring and first anchoring and then grouting. The construction method of grouting first, then anchoring, should pay special attention to the occurrence of grouting quality problems during installation, while the construction method of anchoring first and then grouting should pay attention to the problem of grouting exhaust, otherwise it will easily cause insufficient mortar. Situation, this will directly lead to poor anchoring effect. When following the resin anchor rod, it is usually necessary to use the rod body to send the medicine pack to the bottom of the hole to pierce and stir for 30 seconds to fix the rod body. After 15 minutes, the resin can be cured to 80%?90% of the final strength before installation of the backing board can be carried out.

In the case of low temperature and flowing water (180~390ml/min) in the hole, the resin anchor rod can still be used.

Pre-stressed anchor rod installation, after anchoring the inner anchor head of the anchor rod, the outer anchor end is tensioned with a jack, and a pre-tensioning force of about 10t is applied to each anchor rod, the bolts at the end of the rod body are tightened, and cement mortar is poured in the full length.

Construction steps of split set:

(1) Hole location layout: Hole locations should be arranged and marked according to design requirements and surrounding rock conditions, and the deviation should not be greater than 20cm.

(2) Bolt hole diameter: The hole diameter of the mortar bolt should be 15mm larger than the diameter of the bolt body.

(3) Drilling direction: The bolt hole should be drilled radially along the periphery of the tunnel, but the drilled hole should not be parallel to the rock surface.

(4) Drilling depth: The error of the hole depth of the mortar bolt should not be greater than ±10cm.

(5) The bolt hole should be kept straight.

(6) Clear the hole before grouting: If there is water, rock dust, debris or other debris in the borehole, it will affect the quality of grouting and hinder the insertion of the bolt body, and also affect the effect of the bolt. Therefore, manual or high-pressure wind or water must be used to remove water, rock dust, debris and other debris in the hole before installation of the bolt.