Model Analysis of Cross-hole Resistivity Tomography for Void Detection

Model experiments in the laboratory were used to find the best measuring parameters which affect the quality of results for the improved application of resistivity tomography between boreholes. Plastic tubes of various diameters were used to simulate the boreholes and the tunnel’s void in a big plastic tank with non-ionized water. The experiments have shown that a void can be detected using various diameter sizes and depths, and that the resolution is dependent on the distance of the target from the drillings, the distance between the drillings, the electrode array, the use of various and certain dipole lengths and distances, the measuring protocol, and the extended resistivity model. In general, sensitivity analysis is the main guide.