Some Double Shield TBM Behaviours Tunnelling Through Rock Fault in Water Diversion Project in Northern Thailand
This publication is prepared with the intention of sharing some useful practical information gained during tunneling in Thailand. There are three double shield TBMs now excavating on three tunnels with a length of 25.26 km. Due to difficulty of geological conditions, as a result, the TBMs encountered several complications such as cutterhead clogging, abnormal disc cutter wear, crown collapses and blockages, shield jamming, and high water ingress. The TBMs are equipped with data acquisition systems by the manufacturer and can record a massive amount of data instantaneously during excavation. However, there is an unavoidable issue that the geological condition throughout cutterhead unable to be observed wholly since shields entirely sheltered cutterhead. To overcome this issue, several kinds of valuable information, including shift logging, cutter inspection, water ingress, muck particle size distribution, were recorded during excavation as functions of time and tunnel distance. Almost all relevant information was integrated to evaluate practical parameters, which can be applied basically to indicate the tunnel-machine interaction or “machine behavior”. The monitored data was analyzed several incidents and represented in transparent formats to serve the operators as a tunneling guide; some of them are discussed in this paper.