Tunnel driving unit for use under road or railway - has forward blades to make support carrier upper chords pass below slide carrier lower chord

摘要

The unit is used for driving a tunnel under e.g. a road or railway without disturbing traffic flow. Blade units (2) are introduced ahead of the structure (1) to cut through the earth (9) in such a way that the upper chord of the support carriers (3) slides through directly below the lower chord of the slide carrier (5). There may be seveal pairs of support carriers side by side and on top of each other on the cutting edge units. The support carriers pref. lie on central supports.