Detection Of Typical Physical Properties Of Reconstructed Soil In Mining Area Based On Ground Penetrating Radar

The technology and mechanism of dumping and land reclamation during the reclamation of open-pit coal mine dumps will affect the physical properties of the soil,and thus affect the growth of vegetation.The traditional method of obtaining soil physical properties is time-consuming and laborious,looking for a quick and non-destructive detection of typical soils in mining areas physical methods are of great significance for precise reclamation work.In order to study the typical soil physical properties of the reclaimed land in the mining area,this paper takes the South Dump of China Coal Pingshuo Antaibao Open-pit Mine as the research object,and uses ground penetrating radar(GPR)to measure the physical properties of the soil in the mining area.The effective soil thickness and the spatial differentiation of surface soil gravel were analyzed,and the feasibility of GPR analysis of soil physical properties was discussed.In this study,GPR was used to analyze the spatial differences of typical soil physical properties in the reclamation area of the mining area.One is to provide a basis for GPR to be used for rapid and non-destructive detection of soil physical properties;it can provide researchers with a basis to quickly analyze the soil physical properties of vegetation growth.The specific research results are as follows:(1)The soil moisture content of different slope positions and aspects has certain differences in the depth direction;the absolute value of the difference between the soil volume moisture content and the measured soil volume moisture content retrieved by the Topp model is 3.20% at the maximum and 0.13% at the minimum,The average deviation rate between the measured value and the empirical value is 13.42%,indicating that the Topp model can be used to calculate the soil moisture content of the reclaimed land in the mining area;according to the local strong and weak variable reflection information in the GPR image,it shows the detected sample partly water-rich,can analyze the spatial difference of the sudden water content of reclamation in the mining area.(2)The difference in soil bulk density at different locations in the mine dump and at different depths in the same profile is obvious.The difference in soil bulk density can be analyzed by GPR.When the soil moisture content is small,the soil bulk density is inversely proportional to the amplitude of the electromagnetic wave,and the soil bulk density is proportional to the dielectric constant.The relative size of the soil bulk density can be analyzed.(3)GPR can be used to qualitatively and quantitatively analyze the spatial variation characteristics of effective soil layer thickness.If there is a low-frequency signal with good continuity in the GPR image,it means that there is soil stratification under the detected sample.The depth of the low-frequency signal with good continuity in the GPR image can represent the depth of the effective soil thickness of the reclaimed land in the mining area.Based on the soil moisture content,dielectric constant,electromagnetic wave speed,the actual depth of the soil layer,the depth of the soil layer GPR image to establish a piecewise fitting relationship can be more accurate quantitative determination of effective soil layer thickness.(4)GPR images can be used to characterize the gravel content of surface soil.Through the statistics of the number of isolated gravel signals(parabola downward opening)in the GPR image,the gravel content of the surface soil of the reclaimed ground in the mining area can be analyzed.The greater the number of isolated gravel signals,the higher the gravel content of the surface soil.(5)The three-dimensional image of GPR can be used to examine the spatial differentiation characteristics of soil volumetric moisture content,effective soil layer thickness,surface soil gravel content and soil physical properties in an area.