Geoelectrics-While-Tunneling: Methodology and Performance Aspects

摘要

This paper presents a detailed investigation of electric geophysical techniques that 'look ahead' of the tunnel face during TBM operations for both hard rock and soft ground conditions, called geoelectrics-while-tunneling. These methods utilize integrated components of the TBM as electrodes and use current injection to 'illuminate' the ground ahead of the TBM, identifying changing ground conditions, faults, groundwater inflows, boulders, cavities, utilities etc. Classical earth based methodology, called geoelectrics, is well established and is briefly presented, where many of its aspects can be translated to geoelectrics-while-tunneling. An overview of geoelectrics-while-tunneling is presented pertaining to its geometry, influences on performance, and its allowable electrical current injection limit, so as to better establish these methods for use in industry.