Study On Trough Wave Property Response Characteristics Of HTI Coal Rock Medium

Identifying and reconstructing transparent geological conditions of coal mining is the basic guarantee of accurate mining of coal seam working face.In-seam wave exploration is an important means of geological structure detection of coal seam working face.At present,the simulation research of in-seam wave exploration is mostly based on isotropic medium.Ignoring the anisotropy of coal seam will reduce the accuracy of geological structure exploration.Considering that there are few researches on the in-seam wave attribute response characteristics of HTI medium parameters and structural changes,this paper adopts the methods of theoretical analysis,numerical simulation,tomographic imaging and field test to focus on the response characteristics of the transmitted in-seam wave energy and centroid frequency of HTI medium.The main researches are as follows:(1)Based on two-dimensional HTI medium model,the influence of coal seam γparameter variation and fault drop variation on in-seam wave energy and centroid frequency response characteristics was studied by numerical simulation.The results show that:(1)The variation of γ parameters of coal seam in HTI medium has little influence on the in-seam wave energy and the frequency response characteristics of centroid frequency.(2)The in-seam wave centroid frequency and energy respond to both the one-quarter coal thickness fault and the fault with larger drop,and the abnormal attenuation degree of the in-seam wave centroid frequency and energy increases with the increase of the fault drop.(2)Based on the three-dimensional model of HTI medium,the response of fault drop variation in energy and centroid frequency tomography was studied by numerical simulation.The results show that,with the same characteristics of in-seam wave centroid frequency and energy response,the imaging results based on inseam wave energy and centroid frequency have a response to the fault with a quarter coal thickness and a larger drop.With the increase of the fault drop,the response range of the tomography results also increases.The tomography results of the whole coal thickness fault are the most accurate,and the frequency tomography results of the adjacent channel centroid are more accurate than the in-seam wave energy tomography results.(3)The response characteristics of in-seam wave energy and centroid frequency in HTI medium were further studied through field tests.The actual faults revealed by the working face are two kinds of faults with full coal thickness and those between 1/4coal thickness and 1/3 coal thickness.The response characteristics of in-seam wave energy and centroid frequency to faults with different drop are consistent with the numerical simulation results.The results of working surface tomography based on inseam wave energy and centroid frequency are roughly the same as those of mining,which realizes the accurate exploration of geological structure of coal seam working face by in-seam wave exploration.Figure[25] Table[7] Reference[94]...