| 摘要 |
<p>A method of mining an underground deposit, from which extraction is made difficult by the radioactive and/or toxic nature of the deposit and/or by geological conditions, comprises digging a tunnel through the deposit using a tunnelling machine; reversing the tunnelling machine and digging a tunnel adjacent the first tunnel; and repeating the reversing of the tunnelling machine and digging until the mining of the deposit is complete. The tunnelling machine includes a rotatable cutter 38 on a boom 36; a shield body 28, 30, 32; a crusher 48; a pump 50 for delivering the excavated material to ducts, 42, 44, 74; and a device for installing tunnel lining segments. All or part of the deposit maybe confined by a watertight coffer formed by injecting a hydraulic binder and/or by freezing, and the deposit may be drained. <IMAGE></p> |
