FIELD: mining.
SUBSTANCE: invention relates to the field of mining and the construction of tunnels and other underground facilities in rock where it is necessary to strengthen the roof and side walls with rock bolts to prevent their collapse or slipping. Rock bolt comprises at least one elongated body. Its one end being comprised of at least one first external conical part (16), extending through at least one hole in at least one cylindrical expandable body. Hole in the axial direction comprises at least one internally conical part intended to cooperate with outer conical portion. Expandable body comprises at least one first subsection and at least one second subsection. These subsections divide the cross section of the expandable body into sub-segments. These sub-segments, with relative axial movement of the outer conical portion of the elongated body and the inner conical portion in the opening, influence their positions relative to each other in radial direction of expandable body. Relative axial movement between the elongated body and the expandable body is provided by at least one tensioning device. Rock bolt comprises at least one wedge device. It comprises of at least one wedge shaped part, and that the wedge shaped part, when the rock bolt is inserted into the bore hole, strikes the bore hole's bottom causing the wedge shaped part to be forced between the subsections of the expandable body. In addition, the rock bolt comprises at least one connecting member that holds together the subsections of the expandable body in the opening and is capable of breaking when the body is expanded.
EFFECT: higher rock bolt operating reliability.
11 cl, 6 dwg
