HOLLOW BAR GROUND ANCHOR
Geoizol-MP anchor systems consist of a center load-bearing hollow bar that performs the function of a "drill pipe" as well as the grout channel. Tensile and compression loads are transferred from the load-bearing element to the subsoil through the injected grout. The grout reduces the radial stresses in soil, constraints buckling and protects anchor's steel from corrosion. The root piles are installed with the use of small-sized mobile rigs, which make installation possible in hard-to-reach areas and without suspending train traffic or regular operations of the mine.
The whole process of pile construction is completed in one phase (drilling and grout injection). Washing grout is pumped under pressure of 5–10 bars through the internal channel of the drill pipe (water to cement ratio is 0.7–0.8). The pressure forces the grout into the rock/soild voids thus strengthening the borehole walls and eliminating the need for casing. Both the drill stem and the drilling bit stay inside the borehole performing the function of pile’s center reinforcement. Centralizers are spacers that keep the bar anchor centered inside the borehole.
Steel drill stems are manufactured with diameters ranging from 30 mm to 73 mm and may be cut to required length and joined by couplers. Thus an optimal length and diameter of a root pile can be achieved.