What are Hollow Bar Anchors?
How are Hollow Bar Anchors Installed?
Thanks to the self-drilling hollow bar system with simultaneous grout flushing, the installation procedure can be decisively eased and shortened.
The Hollow Bar serves as a drill rod. It is fitted with a lost drill bit at the top that can be adapted to different soil conditions. After each single section of bar, he subsequent bar is coupled to the previously installed segment.
At the final stage of drilling, cement mortar is injected into the hollow core of the bar using an injection adapter that is mounted at the drilling unit. The grout flushing simultaneously serves as slurry to stabilize the borehole and ensures the efficient retroflush of the borehole cuttings. Once the required installation length has been reached, the grouting unit is switched to grouting mortar because it reaches higher compression strengths and thus ensures better load-bearing capacities.
The hollow bar now serves as a steel tendon and can be used both as a soil nail or rock bolt and as a micropile.