The Numerical Simulation Research Of High-density Electrical Method In Underground Cavity Detection

With the rapid development of China’s economy, large number of infrastructure projectsare constructed rapidly, the construction site may cross the underground cavity, so the spatiallocation, size and the causes of different types of underground voids ascertained has veryimportant significance to ensure the successful completion of project construction.Based on the numerical simulation methods, high-density electrical method in detectingunderground voids researched. First, the forward theory of high-density electrical method isdeduced and obtains the apparent resistivity formula of device. The introduction of robustinversion method and commonly used method of least squares inversion are compared, andthe applicable conditions are obtained and verified. Secondly, through the ANSYS analysismodule of the steady-state current conduction, the numerical simulation method is carried onthe selection of different high-density electrical device parameters and the impact of differenttypes of underground cavity on detection effect. Introduced the impact factor μ to evaluate thedetection effects of different device types, and the influence of electrode spacing, the selectionof the largest pole pitch, different underground voids depths, distribution patterns, resistancevalue, coverage layer thickness and the resolution is discussed to evaluate the impact ofdetection effect. Finally, combined the instances of mined-out areas exploration of Yangjiacoal of Fuyang city and Chaoyang coal of Tonglu county, simulation analysis is conductedwith the geoelectric conditions of2survey lines. The simulation results and field detectionresults are compared and analysised, and verified by the histogram of verify hole.