A METHOD FOR TUNNEL CONSTRUCTION

摘要

There is provided a method of constructing a section of a half-tunnel in a slope (10) of a mountain or hill (12), including the steps of forming a lock block (18) along the section (16) above the upper edge of the half-tunnel to be excavated, inserting lock elements (22) traversing the lock block and extending into the mountain, excavating portions of the mountain beyond and below the lock block defining roof and bottom portions of the half -tunnel, and repeating the excavating procedure until the entire section of the half-tunnel is formed.