Demonstration of Sinorock hollow anchor bar installation

This is a demonstration of hollow anchor bar installation.A new motorway is currently under construction. Sinorock supplied the complete range of important ground control products for tunnel driving. This also included Type R32 and R38  Hollow anchor Bar Rock Bolts including accessories as well as grout pumps. The Sinorock Drill Hollow anchor Bar System proved itself by fulfilling the following technical characteristics in this project:
1 Simultaneous drilling and grouting ensures an optimum bond between the hollow bar tendon and the unconsolidated rock or ground 2 The construction soil is improved by the infiltration of the grout into the surrounding unconsolidated soil 3 Uniform distribution of the grout along the complete installation length Here are the process of hollow anchor bar installation: Hollow anchor bar system is typically installed using rotary percussive drilling. The advanced technique improves the rate of installation, also makes good directional stability and helps to consolidate the grout within the borehole.
Rotation speeds should be sufficient to cut a true borehole, as opposed to displacement of the soil with the drill bit through percussion and heavy feed pressures. Drilled boreholes make enlarged grout bodies possible. It is used together with better permeation of the grout into the surrounding ground.Feed pressures on the hollow anchor bar should be regulated in accordance with the cutting performance of the drill bit. 
Hollow anchor bar system features simultaneous drilling and grouting. It is suitable for granular soils and fills. This installation method utilises a grout swivel, grout pump and drilling head. The advanced technique combines drilling and grouting into a single operation, ensuring that grout is placed over the full length of the borehole. Simultaneous drilling and grouting is the prefered solution for ground conditions where subsequent grout injection down the center of the bar is problematical.
Grouting pressures should be regulated to maintain circulation at all times, with a small amount of grout return visible at the mouth of the borehole. Pressures in excess of 100 psi are generally only required for special applications.