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Expandable Rock Bolts (ERB) are used for rock reinforcement. The ERB is a full column anchored rock bolt that forms a mechanical interlock between the borehole wall and the bolt over the full bolt length. The ERB is inflated using high water pressure. When inflated it causes the bolt length to contract, which in turn tensions the face plate against the rock surface. The ERB is a rock reinforcement solution with no cement grout or other chemicals required to anchor the bolt.