Challenges, countermeasures and development direction of geological forward-prospecting for TBM cluster tunneling in super-long tunnels
DENG Mingjiang1, LIU Bin2
(1. Xinjiang Irtysh River Basin Project Development and Construction Administration, Urumchi 830000, Xinjiang, China;
2. Geotechnical and Structural Engineering Research Center, Shandong University, Jinan 250061, Shandong, China
Abstract In recent years, in some super-long water diversion tunnels, construction methods of multi-headed excavation using multiple TBMs have emerged, forming the characteristics of TBM cluster tunneling. The northern Xinjiang Water Supply Phase II Project is a typical representative. The geological condition of this project is extremely complex. Tunnel construction is faced with many disaster risks such as collapse, water inrush, soft rock deformation with high groundwater, and TBM jamming. There are many high-risk sections and it is of great necessary to carry out geological forward-prospecting. In views of the construction characteristics of TBM cluster and the challenges faced by geological forward-prospecting, the geological conditions and major disaster risks of the project were analyzed, and the features of commonly used geological forward-prospecting techniques were compared. The applicability of forward-prospecting methods under TBM cluster construction conditions as well as the corresponding technical challenges were discussed in detail, and the countermeasures were proposed accordingly. The development direction of TBM geological forward-prospecting technology was further discussed. Recommendations were proposed from the following five aspects: expert decision-making and fusion diagnosis of forward-prospecting for TBM clusters, robust and efficient real-time geological forward-prospecting technology, correct utilization and construction permit of geological forward-prospecting results, TBM intelligent excavation based on “transparent” geological rock mass information and standardization of TBM geological forward-prospecting, etc. These recommendations will be focused and deployed in advance, which will provide guidance for future forward-prospecting in tunnel construction with TBM cluster.
DENG Mingjiang,LIU Bin. Challenges, countermeasures and development direction of geological forward-prospecting for TBM cluster tunneling in super-long tunnels[J]. Hazard Control in Tunnelling and Underground Engineering,
2019, 1(1): 8-19.
