Cutter driven heading or tunnel support shield - support frame as abutment for face plates supported at rear on permanent supports

摘要

Heading or tunnelling shield for cutter dirver headings or galleries consists of a support frame acting as bearing and guidance system for the cutters arranged round the outside of the support frame, and linked to this through hydraulic thrust cylinders. The supporting frame (1) forms the abutment for the face plates (5) resting against the heading (4) and is supported at the rear by the permanent tunnel or heading support structure (6). One of more extensible outriggers (7) are pref. used to carry the frame (1) on the tunner supports at the rear, the outriggers hinged to the main supports for this purpose. The outriggers should be drawn up at intervals, and should be carried in holes (8) made in the in-situ concrete (9) at a reasonable distance from the tunnel or heading face (4).