Advanced geological detection instrument for TBM tunneling based on AC induced polarization method

摘要

Currently, there are some methods for geological prediction method in tunneling using tunnel boring machine (TBM). The Bore-tunnel Electrical Ahead Monitoring (BEAM) is popular in the advanced detection based on the current method of electrical prospecting. However, the drawbacks of BEAM in the cost and complexity limit the application for geological prediction. This paper proposes a novel detection instrument for advanced geological prediction based on the characteristics of BEAM system. The instrument is implemented by the hardware voltage parallel method, which can realize the high speed and high precision measurement of the geological apparent resistivity and dispersion rate in dynamic tunneling process. It selects several cutting head of TBM as the main electrodes, which are set at two kinds of electrode distribution modes. It can achieve good detection results by switching between electrode distribution modes and scanning modes which is available by the rotating of working face. Experiments have been carried out to test for TBM experiment model in the proposed instrument. The results of experiment verify the feasibility and effectiveness of the proposed detection instrument.