| 摘要 |
<p>The method of supporting the sides of a tunnel during advance, for mining operations, uses an overhead framework (1) supported by previously installed sections so that the next section of lining can be positioned. The supports consist of upper pairs of through shaped channels (44) and lower pairs (A) with mesh grids (50) across them for one side of the tunnel, and similar sets for the other side. The overhead framework travels on carriages, with the pre assembled lining members, to the required position. The upper carrier members are secured and by means of telescopic cylinders swing the top ends of the upper pairs of arch members upwards and their bottom ends are swung outwards. The lower pairs of arch members are also swung downwards and outwards for attachment to the sides.</p> |
