METHOD FOR LINING OR relining A TUNNEL, AND SHIELD FOR ASSEMBLY TUNNELFORINGSSEGMENTER an excavated TUNNEL

摘要

A method of constructing a lined or relined tunnel utilizes four lining segments, three of which (1, 2, 3) have a longer arcuate length than the fourth (4). The tunnel is constructed within a shield (20) having a tubular member (21) and a curved build plate (22) having a minimum internal dimension at least the same as the outside radius of the lining. The shield also has a circular skirt (25) the upper part of which is extended rearwardly to form a hood (26). In the method a length of tunnel is excavated and the shield positioned therein, a first segment (1) is positioned on the build plate and the segments (2, 3) then located upon the first segment (1). The ends of the second and third segments (2, 3) remote from the segment (1) are pivoted outwardly to locate the fourth segment (4). The shield is provided with a flexible collar (27) extending from the confluence of the member (21) and skirt (25) interiorly of the shield to provide a seal between the lining segments and the collar against filler material (40), the collar having an L-shape for clampingly securing the collar to the tubular member and skirt combination.