Abstract：The forward and the inverse numerical simulations on the computed tomography of cross-hole resistivity was carried out based on the finite element and the least squares methods for the better geological prediction in urban subway engineering to avoid the potential geological disasters and ensure the construction safety. Three geoelectric models describing the water-filled karst cave，the water-filled fault and the bedrock surface were established respectively. The models were used to analyze the response characteristics and the behaviour and to verify the feasibility of the computed tomography of cross-hole resistivity. Meanwhile，it was pointed out that the computed tomography of cross-hole resistivity could be applied to the other type of cases in the urban subway geological prediction. Three types of layouts of the surveying lines and a 3D slice method of interpretation were presented to resolve the complexity of geological environment of the urban subway. Further case studies showed that the computed tomography of cross-hole resistivity had a high precision of detection and was flexible in implementation and did not interfere with the tunnel excavation.
2014, Vol. 33 
