What is the construction process of Hollow grouting anchor rod？

 Drilling hole
(1) The opening of prestressed anchor bolt holes shall be carried out according to the drilling positions arranged in the construction drawings. If the top of the hole is higher than the hole position, a steel pipe scaffolding operation platform must be erected, and the holes shall be drilled with a pneumatic drill bit and thoroughly cleaned. The depth and diameter of the borehole shall not be less than the design value, and the inclination and azimuth of the borehole shall meet the design requirements.

Anchor rod installation
After the drilling is completed, the anchor rod installation shall be carried out after passing the inspection. The length of a single anchor rod should be 50cm longer than the thickness of the rock and the thickness of the sprayed concrete on both sides in the design, with reserved installation anchor pads and tensioning length. Due to limited workspace on the construction site, some of the excessively long staggered poles should be divided into multiple sections for processing and connected and installed using connecting sleeves. Therefore, in the process of anchor rod production, the installation space size of anchor rods at different positions should be fully considered in order to correctly determine the segmented length of anchor rods

After the installation of the anchor rod, the hole opening is leveled with dry and hard pre shrinkage mortar, and then a qualified cushion plate, nut, and grout stopper are installed to complete the anchoring process. After passing the inspection of the supervisor, a torque wrench is used to directly tension to the design tonnage in one go.

After the prestressed anchor rod is tensioned, immediately use the reserved grouting port to inject grout into the anchor rod. The grout used is cement mortar, with a mix ratio of cement: grouting agent: water=1:0.01:0.38 (1) Inject grout through one end and discharge grout through the other end.