Shield TBM risk model based on Bayesian networks applicable in design stage

초록

A risk management methodology that can be applied in the design stage of a shield tunnel boring machine (TBM) tunneling project is proposed in this paper. A Shield TBM Risk Analysis Model (STRAM) is developed based on Bayesian networks. The STRAM considers geological risk factors and TBM types, such as earth pressure balance (EPB) open mode, EPB closed mode, and slurry TBMs, and systematically identifies the potential risk events that may occur during tunnel construction. It can also quantitatively evaluate the degree of risk for the identified potential risk events by estimating the cost of counter-measures against event occurrence. The proposed methodology based on the STRAM can minimize the drawbacks of the TBM tunneling method, including the difficulty in substituting the machine type once it is selected and the excessive delay of the project caused by unexpected risk events.