PROGRAMME OF LABORATORY PILOT AND FULL-SCALE EXPERIMENTS IN TUNNEL BORING

The paper reviews research being carried out at TRRL aimed at improving the performance of tunnelling machines. From early investigations into the cutting and mechanical properties of chalk, further studies followed on reconstituted chalk and also full-scale trials with a 5 M diameter tunnelling machine. Laboratory tests were also carried out on bunter sandstone and magnesian limestone. In addition, preparations for monitoring the performance of A tunnelling machine in a coal mine are at an advanced stage. /TRRL/