A friction bolt (10) includes a first generally circular tube (12) having an internal diameter and defining a longitudinal split, the tube being radially expandable. The bolt has a first leading end (16) for insertion into a borehole (50), a second end defining a head (18), and a second generally circular tube defining a longitudinal split and having an external diameter which is substantially the same as or larger than the internal diameter of the first generally circular tube. The second tube is located inside the first tube (12) with an exterior of the second tube in contact with the interior of the first tube (12). The friction bolt (10) is installed in a rock face (80) using standard friction bolt (10) installation equipment and methods.

A friction bolt includes a first tube having an internal diameter and defining a longitudinal split, the tube being radially expandable. The bolt has a first leading or distal end for insertion into a bore and a second or proximal end defining a head and further includes a second tube defining a longitudinal split and having an external diameter which is substantially the same as or larger than the internal diameter of the first tube. The second tube is located inside the first tube with its exterior in contact with the interior of the first tube. The bolt includes a slip and lock mechanism that allows the first or exterior and second or interior tubes to move relative to each other along the longitudinal axis of the friction bolt when a tensile force is applied to the bolt, but to lock together after the force is removed.