GB1457178A - Tunneling method and apparatus - Google Patents

Abstract

1457178 Tunnelling GEWERKSCHAFT EISENHUTTE WESTFALIA 22 March 1974 [27 March 1974] 12779/74 Heading E1F A tunnelling technique involves driving two spaced parallel pilot tunnels 2, 2' and interconnecting these by a transverse tunnel following the contour of the roof of the main tunnel which is to be driven along the path between the two pilot tunnels, the transverse tunnel serving to receive a top-heading tunnelling machine comprising an advanceable sectional frame whose sections, e.g. the sections 6-8 of Fig. 2 are pivotally interconnected end-to-end as at 20 and are pivoted relative to each other by rams 21 carrying male fittings 25 received in complementary female fittings 26, the rams optionally being actuated in response to means measuring the loads on the frame. The frame carries groups of tunnelling shield boards 13 of which each group is advanceable while another is held stationary. The frame also includes skids 14 on which is mounted a conveyor 12 supporting a cutter 11 movable along the conveyer to cut away material beneath the boards 13, the debris being conveyed to tunnel 2' for removal. As the frame advances, a roof lining is cast or assembled in the space therebehind, and once the roof lining is able to support a load a high-speed wide-face tunnelling machine is used to excavate the material below the lining to form the main tunnel. In one suggested operating mode, the pilot tunnels are driven a predetermined distance and their leading ends are then interconnected by a transverse tunnel in which the profiled top-heading tunnelling machine described above is installed and moved in reverse direction to form the roof space of the main tunnel between the previously-driven sections of the pilot tunnels, this cycle then being repeated as necessary. In another suggested operating mode, the top heading tunnelling machine advances simultaneously with and in the same direction as the machines driving the pilot tunnels, the latter in either case finally being filled with concrete or lining except in areas defining access passages. The cutter 11 may be a planar with cutting bits or rotary cutting tools, and may be hauled along the conveyor 12 by an endless traction element. In another embodiment, the cutter is replaced by a rotary cutter chain. The material removed by the cutter -11 may alternatively be transfered to the pilot tunnels under gravity or it may be displaced towards the pilot tunnels by the cutter itself. The shield boards 13 and the skids 14 may have retractable anchoring sprags.