Abstract:

The length of the main machine of doubleshield TBM is relatively large, which leads to its position unstable during excavating and regripping cycle process. Another unfavorable factor is the increasing risks of shield jamming when encountering sudden geological fault zone. A new kind of hydraulic supporting equipment (HSE), installed on the bottom of front shield, is proposed. It has two working mode including high pressure supporting mode and low pressure compact mode. The hydraulic supporting equipment can lift the front shield and cutterhead to a appointed height under highpressure mode, which can enrich the expending excavation ways and improve the efficiency and safety of gauge cutter replacement. When working on the lowpressure mode, the HSE can add the support points between front shield and tunnel wall, then decrease the main machine vibration and improve the stability during regripping cycle process. The HSE of the front shield can improve the performance of doubleshield TBM, which has good technical feasibility and popularization value.

Key words: doubleshield TBM, hydraulic supporting equipment, regripping cycle, expanding excavation, gauge cutter replacement