Abstract: The invention provides a grout pack restraining system, comprising a plurality of elongate elements shaped to extend about a grout pack and which are characterized in that they are configured to control circumferential expansion of the grout pack beyond the expansion permitted through material yield of the elements. In one embodiment the rings of different diameter are secured about the grout pack. In a further embodiment the rings are configured to be circumferentially expandable are secured about the grout pack.