Prediction method of ground movement and deformation in mining areas based on segmentation method

Abstract

The present invention discloses a method for predicting surface movement and deformation in a mining area based on a segmentation method, and relates to the technical field of surface movement and deformation prediction. The method of the present invention comprises: first, identifying the position information of the boundary of a goaf area in a mining area, obtaining the coordinate information of the boundary of the goaf area, and establishing a function expression of the boundary of the goaf area in a horizontal rectangular coordinate system according to the coordinate information; then, segmenting the goaf area according to whether the boundary of the goaf area can be represented by the same function expression as a standard; secondly, calculating each segment after segmentation using a formula to obtain the surface subsidence value generated by the segmented goaf area; superimposing the subsidence values ​​of the same surface position of all segmented goaf areas to obtain a complete surface subsidence value; finally, according to the relationship between other surface movement and deformation parameters and the surface subsidence value, obtaining other parameters of surface movement and deformation in the mining area. The present invention improves the efficiency and accuracy of the prediction of surface movement and deformation in the mining area.

Description

Technical Field

[0001] The present invention relates to the technical field of ground surface movement and deformation prediction, and in particular to a method for predicting ground surface movement and deformation in a mining area based on a segmentation method. Background Art

[0002] Coal mining will cause a certain degree of surface movement and deformation, which will have an adverse impact on the surface morphology and the safety and stability of related buildings (structures). How to accurately predict the degree of surface movement and deformation after coal mining is crucial for mining damage prevention and environmental protection. The currently commonly used method for predicting surface movement and deformation in mining areas is the probability integral method. The principle of this method is to regard the overlying strata of the goaf as multiple small balls, and take the probability of the small balls falling into the goaf as the corresponding surface subsidence value. With the help of this method, a more accurate surface movement and deformation situation can be obtained.

[0003] At present, there are many research reports on the application of probability integral method to predict surface movement deformation in rectangular working face mining, but there are errors or large errors in the prediction of surface movement deformation in complex-shaped working face mining. The main reasons are: First, when the existing technology predicts surface movement deformation by probability integral method, from two-dimensional (stratum longitudinal profile) to three-dimensional application process, researchers often ignore the relationship between two orthogonal integral variables, and stereotype that there is no correlation between the variables in the two integral directions, which has no effect on the prediction results when solving rectangular working face mining, but will cause errors in the prediction of surface deformation in non-rectangular working face mining, resulting in this method being prone to prediction errors when solving the prediction of surface movement deformation in mining areas with complex boundary shape working faces; second, the prediction of surface movement deformation in mining areas with complex boundary shape working faces needs to be carried out according to a certain method, but there is currently no efficient and accurate prediction method.

[0004] This shows that the prior art needs to be further improved. Summary of the invention

[0005] In order to solve the problems of being unable to start and difficult to accurately calculate the surface movement and deformation prediction in mining areas with complex boundary shapes, the present invention provides a method for predicting the surface movement and deformation in mining areas based on a segmentation method, which improves the efficiency and accuracy of predicting the surface movement and deformation in mining areas.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: a method for predicting surface movement and deformation in a mining area based on a segmentation method, comprising the following steps: a. identifying the position information of the boundary of a goaf in a mining area to obtain the coordinate information of the boundary of the goaf, and establishing a function expression of the boundary of the goaf in a horizontal rectangular coordinate system according to the coordinate information; b. segmenting the goaf according to whether the boundary of the goaf can be expressed by the same function expression; c. calculating each segment after segmentation using formula (1) to obtain the surface subsidence value generated by the goaf of the segment.

[0007] (1).

[0008] In formula (1): W(x, y) is the subsidence value of the mining area surface (x, y); W cm ——The maximum subsidence value of the mining area surface, which is a known parameter; H——The burial depth of the coal seam (or goaf) corresponding to the point on the mining area surface vertically; tanβ——The tangent of the main influencing angle; t i-1 ——Boundary of goaf P i-1 The t-direction coordinate of the point; t i ——Boundary of goaf P i The t-direction coordinate of the point; x——the t-direction coordinate of the surface point of the mining area; y——the ρ-direction coordinate of the surface point of the mining area, the ρ direction and the t direction form a plane rectangular coordinate system; π——the pi; e——the base of the natural logarithm; σ——the integral variable; erf(p)——the probability integral function, p represents the variable; f2(t)——the function expression of the second boundary of the goaf, ρ2=f2(t); f1(t)——the function expression of the first boundary of the goaf, ρ1=f1(t).

[0009] d. Superimpose the subsidence values ​​of all segmented goaf areas at the same surface position to obtain the complete surface subsidence value.

[0010] e. Based on the relationship between other surface movement deformation parameters and surface subsidence values, other parameter data of surface movement in the mining area are obtained, including inclination, curvature, horizontal movement and horizontal deformation.

[0011] The above-mentioned method for predicting surface movement and deformation of a mining area based on the segmentation method contains two sets of rectangular coordinate systems in formula (1), namely the x, y coordinate system and the t, ρ coordinate system. The x, y coordinate system represents the surface position of the mining area, and the t, ρ coordinate system represents the position of the goaf. The projections of the two sets of rectangular coordinate systems on the horizontal plane are overlapping.

[0012] In the above-mentioned method for predicting surface movement and deformation in mining areas based on segmentation method, formula (1) is calculated with the aid of a computer.

[0013] Compared with the prior art, the present invention brings the following beneficial technical effects: (1) A method for estimating the surface movement deformation of any mining working face based on the probability integral method (authorization announcement number CN106446379B) discloses a method for estimating the surface movement deformation of any mining working face based on the probability integral method. The method proposes a method for processing the mining area using the vector product method for any mining area of ​​any shape, and then divides the processed mining area into several approximately rectangular mining areas along the strike for calculation, and accumulates the surface movement deformation value of the entire mining area. The method also uses the Python language to programmatically implement the prediction of the surface movement deformation value of any mining area of ​​any shape, the drawing of two-dimensional, three-dimensional, and cloud maps, and the output of calculation data files. Compared with the above, the present invention is equivalent to proposing a method for calculating the surface movement deformation value of any mining area with a different concept. The method can realize the prediction of the surface movement deformation of the mining working face with complex boundary shapes by combining the formula (1) with a computer. The present invention does not need to simplify the boundary of the goaf area, and always maintains the initial shape, thereby simplifying the calculation steps.

[0014] (2) The present invention can realize the prediction of surface movement and deformation of working faces with complex shapes through the proposed surface subsidence prediction formula for working faces with arbitrary boundary shapes and a relatively simple prediction division method, without having to subdivide the goaf into a large number of rectangles or triangles, thereby simplifying the calculation process and not reducing the prediction accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the method for using formula (1) of the present invention.

[0016] Figure 2 It is a schematic diagram of the prediction of surface movement and deformation in a mining area according to the present invention.

[0017] In the figure: P1, the first boundary point, P2, the second boundary point, P3, the third boundary point, P4, the fourth boundary point, P5, the fifth boundary point, P6, the sixth boundary point, P7, the seventh boundary point, P8, the eighth boundary point, P3', the newly added boundary point, O, the origin of the x and y coordinate systems, O', the origin of the t and ρ coordinate systems. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0019] In the description of this application, words such as "first" and "second" are only used to distinguish different objects, and do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit differences. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0020] The technical solution of the present application is further described in detail below in conjunction with the accompanying drawings.

[0021] A method for predicting surface movement and deformation in a mining area based on a segmentation method comprises the following steps: Step 1, identifying the position information of the boundary of a goaf in the mining area, obtaining the coordinate information of the boundary of the goaf, and establishing a function expression of the boundary of the goaf in a horizontal rectangular coordinate system according to the coordinate information.

[0022] Step 2: Segment the goaf based on whether its boundaries can be expressed by the same function expression.

[0023] Step 3: Calculate each segment after segmentation using formula (1) to obtain the ground subsidence value caused by the goaf of the segment. The calculation of formula (1) can be realized by a person skilled in the art with the help of a computer.

[0024] (1).

[0025] In formula (1): W(x, y) is the subsidence value of the mining area surface (x, y); W cm ——The maximum subsidence value of the mining area surface, which is a known parameter; H——The burial depth of the coal seam (or goaf) corresponding to the point on the mining area surface vertically; tanβ——The tangent of the main influencing angle; t i-1 ——Boundary of goaf P i-1 The t-direction coordinate of the point; t i ——Boundary of goaf P i The t-direction coordinate of the point; x——the t-direction coordinate of the surface point of the mining area; y——the ρ-direction coordinate of the surface point of the mining area, the ρ direction and the t direction form a plane rectangular coordinate system; π——the pi; e——the base of the natural logarithm; σ——the integral variable; erf(p)——the probability integral function, p represents the variable; f2(t)——the function expression of the second boundary of the goaf, ρ2=f2(t); f1(t)——the function expression of the first boundary of the goaf, ρ1=f1(t).

[0026] Step 4: Superimpose the subsidence values ​​of all segmented goaf areas at the same surface position to obtain the complete surface subsidence value.

[0027] Step 5: Based on the relationship between other surface movement and deformation parameters and the surface subsidence value, other parameters of the surface movement and deformation in the mining area are obtained, including surface inclination, curvature, horizontal movement and horizontal deformation.

[0028] Formula (1) contains two sets of rectangular coordinate systems, namely the x, y coordinate system and the t, ρ coordinate system. The origin of the x and y coordinate systems is O, and the origin of the t and ρ coordinate systems is O'. The x, y coordinate system represents the surface position of the mining area, and the t, ρ coordinate system represents the position of the goaf. The projections of the two coordinate systems on the horizontal plane coincide.

[0029] The integral of the above formula (1) is for the goaf. For the boundary that cannot be expressed by the integral variable because it is perpendicular to the integral direction, no calculation is required, such as Figure 1 The boundary of the line connecting the second boundary point P2 to the third boundary point P3 does not need to be calculated.

[0030] Example 1: Figure 2 As shown in the figure, the goaf has complex boundaries such as jagged boundaries and curved boundaries. Figure 2 In the figure, the goaf shape is formed by connecting the first boundary point P1, the second boundary point P2, the third boundary point P3, the fourth boundary point P4, the fifth boundary point P5, the sixth boundary point P6, the seventh boundary point P7 and the eighth boundary point P8 in sequence. The function expressions for establishing the boundary of the goaf based on the t direction are f 1-2 (t)、f 2-3 (t)、f 3-3’ (t)、f 3’-4 (t)、f 4-5 (t)、f 5-6 (t)、f 6-7 (t)、f 7-8 (t)、f 8-1 (t). Among them, f 1-2 (t) is a line segment perpendicular to the t direction and cannot be expressed by the f(t) function. This boundary is not used as a calculation boundary. The line connecting the third boundary point P3 and the fourth boundary point P4 is a continuous differentiable curve. Because of the taken t direction, a new boundary point P3' must be added for subsequent segmented calculations. The position of the new boundary point P3' is the point on the curve boundary where the tangent is perpendicular to the selected t direction. If the curve does not have a point where the tangent is perpendicular to the t direction, there is no need to set a new boundary point P3'.

[0031] The goaf is divided according to whether the boundary of the goaf can be expressed by the same function. Then, the above formula (1) is applied to each area from small to large in the t direction for calculation. In addition, for the case where there are multiple integral areas in the same segment (such as Figure 2 ⑥ and ⑦ in the figure are also calculated one by one using the above formula (1).

[0032] Finally, the calculation results obtained in all the integral areas are superimposed with the subsidence values ​​of the same surface position to obtain the complete surface subsidence value; then, based on the relationship between other surface movement and deformation parameters and the subsidence value, other parameter data of the surface movement and deformation of the mining area can be obtained, including surface inclination, curvature, horizontal movement and horizontal deformation.

[0033] Parts not described in the present invention can be implemented by those skilled in the art by referring to the existing technology.

[0034] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present application and are not intended to be limiting of the present application. As long as they are within the spirit of the present application, appropriate changes and modifications to the above embodiments should fall within the scope of protection of the claims of the present application.

Claims

1. A method for predicting surface movement and deformation in a mining area based on a segmentation method, characterized in that: The following steps are involved: a. Identify the location information of the boundary of the goaf in the mining area, obtain the coordinate information of the boundary of the goaf, and establish a function expression of the boundary of the goaf in the horizontal rectangular coordinate system according to the coordinate information; b. Segment the goaf based on whether the boundary of the goaf can be expressed by the same function expression; c. Calculate each segment using formula (1) to obtain the ground subsidence value caused by the goaf in the segment; （1）； In formula (1): W (x, y) - the subsidence value of the mining area surface (x, y); W cm ——The maximum subsidence value of the mining area surface, which is a known parameter; H——the vertical burial depth of the coal seam or goaf corresponding to the point on the surface of the mining area; tanβ——mainly affects the tangent of the angle; t i-1 ——Boundary of goaf P i-1 The t-direction coordinate of the point; t i ——Boundary of goaf P i The t-direction coordinate of the point; x——the coordinate of the surface point in the mining area in the t direction; y——the ρ direction coordinate of the surface point of the mining area. The ρ direction and the t direction form a plane rectangular coordinate system; π——pi; e——the base of natural logarithms; σ——integral variable; erf(p)——probability integral function, p represents the variable; f2(t)——Function expression of the second boundary of the goaf, ρ2=f2(t); f1(t)——Function expression of goaf boundary 1, ρ1=f1(t); d. Superimpose the subsidence values ​​of all the subdivided goaf areas at the same surface position to obtain the complete surface subsidence value; e. According to the relationship between other surface movement and deformation parameters and the surface subsidence value, other parameters of surface movement and deformation in the mining area are obtained, wherein the other parameters include inclination, curvature, horizontal movement and horizontal deformation.

2. The method for predicting surface movement and deformation in a mining area based on segmentation method according to claim 1 is characterized in that: Formula (1) contains two sets of rectangular coordinate systems, namely the x, y coordinate system and the t, ρ coordinate system. The x, y coordinate system represents the surface position of the mining area, and the t, ρ coordinate system represents the position of the goaf. The projections of the two sets of rectangular coordinate systems on the horizontal plane coincide.

3. The method for predicting surface movement and deformation in a mining area based on segmentation method according to claim 1 is characterized in that: Formula (1) is calculated with the aid of a computer.

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