Abstract: A rock bolt for being grouted in a borehole, —includes an elongate cylindrical massive stem (1) with extensive lengths of stem portions (1s) separated by integrated anchors (2). The anchors are distributed with separations along the length of the stem (1). The anchors (2) are locally anchored relative to their local borehole wall portions for taking up load arising due to rock deformation. The stem portions (1s) are arranged for slipping relative to the grout or the borehole so as for each of the stems (1s) to take up local elongation strain between pairs of locally anchored preceding and consecutive anchors.

Abstract: The invention is a rock bolt for being grouted in a borehole, said rock bolt comprising: —an elongate cylindrical massive stem (1) comprising extensive lengths of stem portions (1s) separated by integrated anchors (2) distributed with separations (L3) along the length of said stem (1), —said anchors (2) for being locally anchored relative to their local borehole wall portions for taking up load arising due to rock deformation, —said stem portions (1s) arranged for slipping relative to the grout or the borehole, so as for each of said stems (1s) to take up local elongation strain between pairs of a locally anchored preceding anchor (2a, 2b, . . . ) and a locally anchored consecutive anchor (2b, 2c, . . . ).