Study On Prediction Method Of Concealed Structures In Working Face Based On Gas Drainage Borehole

The small buried structures in coal seam will not only affect the mine normal construction and production, but also is the main factor to induce the mine geological disasters occurred frequently, seriously threatens the safety of people’s life and property. Therefore, how to forecast the coal buried small structure effectively has the important practical significance, and the current research on prediction of coal seam buried small structure has become an important topic.In this paper, based on a large number of gas drainage engineering borehole data, puts forward a method of using wear layer of gas drainage holes to predict small buried structure in coal seam. This paper analyzes several important factors that affect the accuracy of prediction, the occurrence of structure, borehole deviation, data measuring and recording error etc. Focuses on the effects of borehole deviation produced on forecasting precision, and gives some measures to guarantee accuracy of borehole data,improvement of the gas drainage record, reducing measurement error, correction and screening of borehole data, preventing borehole deviation and comprehensive utilization of gas and geological information. Then four index for judging the prediction of buried structures and two kinds of analysis method were put forward: four indicators are the coal seam 3D surface map, contour map of coal seam top(bottom), coal seam isopach map, quantitative map of gas dynamic phenomenon and two analysis methods are the method of trend surface analysis and surface polishing method.This paper studies the calculating method of control point about the wear layer of gas drainage borehole in the coal seam top(bottom)plate, The calculation method of coal seam thickness,The method of borehole deviation correction,The discriminant analysis method of small concealed structure seam.established the mathematical model of each stage in the process of prediction, and the corresponding program is designed by using MATLAB software, then develop the prediction system of small blind structure based on MATLAB software’ GUI function, the interface of the system is simple, easy to operate, and it is suitable for most people to use, so as to facilitate the promotion of the method.By means of the forecast system to predict in the 14171 and 16021 two working faces of Guhanshan mine, the predicted results show that: a small fault exists in the size within the range from 350 to 370 m of 14171 working face, the gap is about 1.3m, the fault strike is N42W; And a fold exists in the size within the range from 150 to 250 m of 16021 working face, the wavelength is about 100 m,and the fold strike is S58E; The prediction results show that the method is feasible.