The grout mix is an essential part of the self-drilling anchor system providing the interface between the bar and the ground formation. Placement of the grout mix can either be subsequent to the drilling which is referred to as Post Grouting or combined with the drilling which is called Simultaneous Drilling and Grouting. Depending on the method to be used, the appropriate grouting equipment needs to be planned and set up prior to installation.
The basic grouting equipment consist of:
A mixing unit in which all ingredients are brought together always in the same sequence. First the water, then cement and finally the defined admixtures ( eg. Filler such as flyash or ultra fine sand, chemical additives such as plasticers and/ or non shrink additives). The mixing unit shall be capable of producing a grout of uniform consistency with the workability and strength characteristics required by the design.
A pump unit with sufficient pressure capacity to transport the homogeneously mixed grout paste through the grout hose and the hollow system of the MAI self drilling anchor bar, exiting at the drill bit through the flush holes and filling the annulus of the borehole until it exits at the borehole mouth.
Suitable grouting equipment available and recommended are:
a)Separate mixing and pumping unit such as the Uni-grout grouting platforms
b) A single pass mixing and pumping unit like the MAI grout pump M400 NT