Closed-face Tunnelling Machines and Ground Stability: A Guideline for Best PracticeThis report is produced in response to a series of incidents of ground instability and collapse that have occurred on recent tunnelling projects in suburban and city centre environments on which closed-face tunnelling machines were used. The purpose of this report is to examine the potential for ground instability or collapse when using closed face tunnelling machines, to investigate the efficacy of various ground investigation techniques in urban areas, and to recommend management and operational guidelines to further minimise the risk when tunnelling beneath highly developed urban and city centre areas. |
Contents
Introduction | 1 |
Choosing between earth pressure balance machines | 9 |
Incident data 15 5559 | 15 |
Copyright | |
7 other sections not shown
Common terms and phrases
annular grout annulus anomalies areas articulation belt weighers bentonite boreholes boulders bulkhead Channel Tunnel Rail clay closed-face machine closed-face TBM closed-face tunnelling machines compressed air conditioning agent construction continuous conveyor Crossrail CTRL cutter cutterhead torque data-logger diameter earth pressure balance Electrical resistivity imaging engineers ensure EPBM excavated quantity excavated spoil excavation cycle extrados Figure foam ground conditions ground investigation ground movement ground stability ground types groundwater grout injection hazards hydrostatic in-tunnel incidents Lavender Street muck skips operating parameters operating pressure over-excavation plenum polymer potential records ring build ring of segments risk management river S/C S/C screw conveyor segmental lining shield body side-scan sonar site investigation Slurry tunnelling machines soil spoil conditioning spoil quantity STM systems subsurface surfactant tail seal tailskin TBM operating TBM's tunnel boring machines tunnel face tunnel lining Tunnel Rail Link tunnelling process tunnelling projects urban tunnelling volume