Method of and apparatus for supporting an overburden

摘要

A method and an arrangement are disclosed for supporting a roof of an underground excavation. A hollow prop casing of two or more telescopable sections is erected and telescoped apart until it bears on the floor and the roof. The sections are then biased against the floor and the roof and the prop casing is filled with a hardenable substance which upon hardening forms in the casing a solid column capable of supporting the roof.