InSAR-based Measurement Method for Angle of Critical Deformation in Coal Mining Area and System

Abstract

The present invention discloses an InSAR-based measurement method and system for angle of critical deformation in a coal mining area, and relates to the technical field of geological disaster prevention and control of mountainous coal mines, comprising: acquiring a mining surface deformation field image using a small baseline subset interferometric synthetic aperture radar; and drawing profile lines along the strike direction and dip direction of the coal seam respectively in the mining surface deformation field image. The method provided by the present invention has the advantages of improving time resolution and reducing phase noise.

Claims

1. An InSAR-based measurement method for angle of critical deformation in a coal mining area, comprising: acquiring a mining surface deformation field image using a small baseline subset interferometric synthetic aperture radar; drawing profile lines along the strike direction and dip direction of the coal seam respectively in the mining surface deformation field image, and selecting n target deformation points as monitoring points on the profile lines respectively; carrying out two-dimensional decomposition ignoring north-south directional deformation contribution on monitoring point data according to satellite incidence angles and satellite fly directions and azimuth angles, so as to obtain vertical and horizontal deformation values; calculating incline, curvature and horizontal deformation parameters with the combination of vertical and horizontal deformation results of two-dimensional decomposition according to a probability integral method; and drawing a curve chart according to vertical deformation of a target area and parameters above, and acquiring a corresponding angle of critical deformation value in a study scope within 10 mm of vertical deformation with strike and dip profile maps.

2. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 1, wherein the acquiring mining surface deformation field image comprises image calibration, interference handling, coherent phase analysis and data interpretation; image calibration comprises atmospheric calibration and radiation calibration; interference handling comprises calculating interference images at different time points; coherent phase analysis comprises acquiring coherent phase history of each pixel and detecting surface displacement signals; data interpretation comprises acquiring lifting and subsidence phenomena of the target area according to data; and the selecting n target deformation points as monitoring points comprises taking the length through the goaf of the strike and dip profile lines of the coal seam, wherein the profile lines are of equal length, so that the number of monitoring points are equal.

3. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 2, wherein the two-dimensional decomposition is expressed as: ${\begin{matrix} D_{T_{1}, T_{2}} = d_{U} \cos d_{E} \sin \cos (\frac{3}{2}) \\ D_{T_{1}^{}, T_{2}^{}}^{} = d_{U} \cos^{} d_{E} \sin^{} \cos (^{} \frac{3}{2}) \end{matrix}}$ wherein represents the incidence angle of a satellite image; represents the included angle of the satellite fly direction and the north direction; -3/2 represents the included angle of the projection angle and the north direction in the satellite sight direction on the ground; T.sub.1 and T.sub.2 represent the acquisition time of two-scene satellite data of a same ascending; D.sub.T1,T2 represents deformation of the radar sight direction within the time from T.sub.1 to T.sub.2; d.sub.U represents the deformation in the vertical direction; d.sub.E represents the deformation in the horizontal east-west direction; the deformation of the descending radar sight direction is D.sub.T1,T2; T.sub.1 and T.sub.2 respectively represent acquisition time of data; represents an incidence angle of a satellite descending image; and a and a respectively represent the included angle of the satellite fly direction and the north direction.

4. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 3, wherein the probability integral method is expressed as: $W (x, z) = W_{0} (\frac{1}{\sqrt{}}_{0}^{\frac{\sqrt{x}}{r_{z}}} e^{^{2}} d + \frac{1}{2})$ $i (x, z) = \frac{d W}{d x} = \frac{W_{0}}{r_{z}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $k (x, z) = \frac{d i}{d x} = \frac{2 W_{0} x}{r_{z}^{3}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $U (x, z) = B_{z} \frac{d W}{d x} = \frac{B_{z} W_{0}}{r_{z}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $(x, z) = \frac{d U}{d x} = \frac{2 W_{0} B_{z} x}{r_{z}^{3}} e^{\frac{x 2}{r_{z}^{2}}}$ $W_{0} = mq \cos$ $r_{z} = \sqrt{4 A} = \frac{H}{\tan}$ wherein W.sub.0 is a maximum surface subsidence value; r.sub.z is a main radius of influence; is a horizontal integral distance; m is an ore mining depth; q is a subsidence coefficient; is an ore bed dip; A is a constant; H is a mining depth; tan is a main influence angle tangent value; i represents incline; k represents curvature; U represents a horizontal displacement value; B.sub.z represents a horizontal movement coefficient; and & represents horizontal deformation.

5. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 4, wherein the angle of critical deformation is that under the circumstance of critical mining, critical deformation values are calculated and dangerous moving boundaries are determined using a group of critical deformation values under current criteria, $i = 3 mm / m, = 2 mm / m, k = 0.2 10^{3} / m$ generate cross points, the outermost point of all cross points of the critical deformation values within 10 mm is projected vertically onto a connecting line of a ground point and a boundary point of the goaf, and then the included angle formed by the connecting line and the horizontal line is the angle of critical deformation.

6. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 5, wherein the angle of critical deformation comprises that on the basis of taking points on defined angle of critical deformation, if the vertical subsidence curve exceeds 10 mm on the outermost side of the profile, an outermost point of the cross point of the critical deformation curve is selected, and the included angle of the connecting point passing through the point and the outermost cross point of a target coal seam and the horizontal line is the angle of critical deformation.

7. The InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 6, wherein the angle of critical deformation further comprises that when goafs that the profile lines pass through are not consecutive, according to time sections reaching sufficient subsidence, corresponding coal seams and subsidence curve fluctuation trend, a cross point of the critical deformation value is vertically projected onto the ground point, and the included angle of the connecting line of the point and the outermost cross point of the target coal seam and the horizontal line is the angle of critical deformation.

8. A system of the InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 7, comprising: a data acquisition module, a deformation field analysis module, a deformation parameter calculation module and an angle of critical deformation value extraction module, wherein the data acquisition module is used for acquiring InSAR satellite data, carrying out atmospheric and radiation calibration, calculating interference images at different time points, analyzing coherent phase history of each pixel, and detecting surface displacement signals; the deformation field analysis module is used for analyzing processed data using the small baseline subset interferometric synthetic aperture radar, extracting surface deformation information, drawing profile lines in coal seam strike and dip directions, and selecting monitoring points; the deformation parameter calculation module is used for calculating incline, curvature and horizontal deformation parameters based on two-dimensional decomposition results with the probability integral method by examining satellite incidence angles and fly direction and azimuth angles; and the angle of critical deformation value extraction module is used for drawing a curve chart and determining an angle of critical deformation value according to vertical deformation and other parameters obtained through calculation, and illustrating data in graphs.

9. A computer device, comprising a memory and a processor, wherein the memory is used for storing computer programs; and the steps of the InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 7 are achieved when the computer programs are executed by the processor.

10. A computer readable storage medium, with computer programs stored thereon, wherein the steps of the InSAR-based measurement method for angle of critical deformation in the coal mining area according to claim 7 are achieved when the computer programs are executed by the processor.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to describe the technical solutions in the examples of the present disclosure more clearly, a brief description of the accompanying drawings required for describing the examples will be provided below. Obviously, the accompanying drawings in the following description show merely some examples of the present disclosure. Those of ordinary skill in the art can also derive other accompanying drawings from these accompanying drawings without making creative efforts.

[0028] FIG. 1 is an overall flow chart of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by one embodiment of the present invention;

[0029] FIG. 2 is a comparison diagram of load balancing rate of multiple algorithm under same task requests of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a second embodiment of the present invention;

[0030] FIG. 3 is an operation time diagram of different repeat times of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a second embodiment of the present invention;

[0031] FIG. 4 is a schematic diagram of strike curvature and subsidence curves of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a fourth embodiment of the present invention;

[0032] FIG. 5 is a schematic diagram of strike angle of critical deformation measurement of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a fourth embodiment of the present invention;

[0033] FIG. 6 is a schematic diagram of dip curvature and subsidence curves of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a fourth embodiment of the present invention; and

[0034] FIG. 7 is a schematic diagram of dip angle of critical deformation measurement of an InSAR-based measurement method for angle of critical deformation in a coal mining area provided by a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] In order to make the aforementioned purposes, features and advantages of the present invention more apparent and comprehensible, detailed descriptions of specific embodiments of the present invention are provided below in conjunction with the appended drawings. Apparently, the described embodiments are only part of the embodiments of the present invention, not all of them. On the basis of the examples of the present invention, all other examples obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0036] A number of specific details are set forth in the description below to provide a thorough understanding for the present invention, however, the present invention may also be implemented in other manners different from those described herein, and those skilled in the art may make similar generalization without departing from the essence of the present invention, therefore, the present invention is not limited by the specific examples disclosed below.

Embodiment 1

[0037] Referring to FIG. 1, as an embodiment of the present invention, an InSAR-based measurement method for angle of critical deformation in a coal mining area is provided, including: [0038] acquiring a mining surface deformation field image using a small baseline subset interferometric synthetic aperture radar; [0039] drawing profile lines along the strike direction and dip direction of the coal seam respectively in the mining surface deformation field image, and selecting n target deformation points as monitoring points on the profile lines respectively; [0040] carrying out two-dimensional decomposition ignoring north-south directional deformation contribution on monitoring point data according to satellite incidence angles and satellite fly directions and azimuth angles, so as to obtain vertical and horizontal deformation values; [0041] calculating incline, curvature and horizontal deformation parameters with the combination of vertical and horizontal deformation results of two-dimensional decomposition according to a probability integral method; and [0042] drawing a curve chart according to vertical deformation of a target area and parameters above, and acquiring a corresponding angle of critical deformation value in a study scope within 10 mm of vertical deformation with strike and dip profile maps.

[0043] The acquiring the mining surface deformation field image includes image calibration, interference handling, coherent phase analysis and data interpretation.

[0044] The image calibration includes atmospheric calibration and radiation calibration. The interference handling includes calculating interference images at different time points. The coherent phase analysis includes acquiring coherent phase history of each pixel and detecting surface displacement signals. The data interpretation includes acquiring lifting and subsidence phenomena of the target area according to data.

[0045] The selecting n target deformation points as monitoring points includes taking the length through the goaf of the strike and dip profile lines of the coal seam, wherein the profile lines are of equal length, so that the number of monitoring points are equal.

[0046] Two-dimensional decomposition is expressed as,

[00004] ${\begin{matrix} D_{T_{1}, T_{2}} = d_{U} \cos d_{E} \sin \cos (\frac{3}{2}) \\ D_{T_{1}^{}, T_{2}^{}}^{} = d_{U} \cos^{} d_{E} \sin^{} \cos (^{} \frac{3}{2}) \end{matrix}}$ [0047] wherein represents the incidence angle of a satellite image; represents the included angle of the satellite fly direction and the north direction; and -3/2 represents the included angle of the projection angle and the north direction in the satellite sight direction on the ground. T.sub.1 and T.sub.2 represent the acquisition time of two-scene satellite data of a same ascending; D.sub.T1,T2 represents deformation of the radar sight direction within the time from T.sub.1 to T.sub.2; d.sub.U represents the deformation in the vertical direction; and d.sub.E represents the deformation in the horizontal east-west direction. The deformation of the descending radar sight direction is D.sub.T1,T2; T.sub.1 and T.sub.2 respectively represent acquisition time of data; represents an incidence angle of a satellite descending image; and a and a respectively represent the included angle of the satellite fly direction and the north direction.

[0048] The probability integral method is expressed as,

[00005] $W (x, z) = W_{0} (\frac{1}{\sqrt{}}_{0}^{\frac{\sqrt{x}}{r_{z}}} e^{^{2}} d + \frac{1}{2})$ $i (x, z) = \frac{d W}{d x} = \frac{W_{0}}{r_{z}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $k (x, z) = \frac{d i}{d x} = \frac{2 W_{0} x}{r_{z}^{3}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $U (x, z) = B_{z} \frac{d W}{d x} = \frac{B_{z} W_{0}}{r_{z}} e^{\frac{x^{2}}{r_{s}^{2}}}$ $(x, z) = \frac{d U}{d x} = \frac{2 W_{0} B_{z} x}{r_{z}^{3}} e^{\frac{x 2}{r_{s}^{2}}}$ $W_{0} = mq \cos$ $r_{z} = \sqrt{4 A} = \frac{H}{\tan}$ [0049] wherein W.sub.0 is a maximum surface subsidence value; r.sub.z is a main radius of influence; is a horizontal integral distance; m is an ore mining depth; q is a subsidence coefficient; is an ore bed dip; A is a constant; H is a mining depth; and tan is a main influence angle tangent value. i represents incline; k represents curvature; U represents a horizontal displacement value; B.sub.z represents a horizontal movement coefficient; and represents horizontal deformation.

[0050] The angle of critical deformation is that under the circumstance of full subsidence, critical deformation values are calculated and dangerous moving boundaries are determined using a group of critical deformation values under current criteria,

[00006] $i = 3 mm / m, = 2 mm / m, k = 0.2 10^{3} / m$ [0051] generate cross points, the outermost point of all cross points of the critical deformation values within 10 mm is projected vertically onto a connecting line of a ground point and a boundary point of the goaf, and then the included angle formed by the connecting line and the horizontal line is the angle of critical deformation.

[0052] The angle of critical deformation includes that on the basis of taking points on defined angle of critical deformation, if the vertical subsidence curve exceeds 10 mm on the outermost side of the profile, an outermost point of the cross point of the critical deformation curve is selected, and the included angle of the connecting point passing through the point and the outermost cross point of a target coal seam and the horizontal line is the angle of critical deformation.

[0053] The angle of critical deformation further includes that when goafs that the profile lines pass through are not consecutive, according to time sections reaching sufficient subsidence, corresponding coal seams and subsidence curve fluctuation trend, a cross point of the critical deformation value is vertically projected onto the ground point, and the included angle of the connecting line of the point and the outermost cross point of the target coal seam and the horizontal line is the angle of critical deformation.

Embodiment 2

[0054] Referring to FIG. 3, as an embodiment of the present invention, an InSAR-based measurement system for angle of critical deformation in a coal mining area is provided, including: [0055] a data acquisition module, a deformation field analysis module, a deformation parameter calculation module and an angle of critical deformation value extraction module.

[0056] The data acquisition module is used for acquiring InSAR satellite data, carrying out atmospheric and radiation calibration, calculating interference images at different time points, analyzing coherent phase history of each pixel, and detecting surface displacement signals.

[0057] The deformation field analysis module is used for analyzing processed data using the small baseline subset interferometric synthetic aperture radar, extracting surface deformation information, drawing profile lines in coal seam strike and dip directions, and selecting monitoring points.

[0058] The deformation parameter calculation module is used for calculating incline, curvature and horizontal deformation parameters based on two-dimensional decomposition results with the probability integral method by examining satellite incidence angles and fly direction and azimuth angles.

[0059] The angle of critical deformation value extraction module is used for drawing a curve chart and determining an angle of critical deformation value according to vertical deformation and other parameters obtained through calculation, and illustrating data in graphs.

Embodiment 3

[0060] An embodiment of the present invention, different from the two former embodiments in that:

[0061] The above functions, if implemented in the form of software functional units and sold or used as stand-alone products, can be stored in a computer readable storage medium. On the basis of this understanding, the technical solution of the present invention essentially or a part that contributes to the prior art, or a part of the technical solution may be embodied in the form of a software product, and the computer software product is stored in a storage medium and includes a plurality of instructions which are used for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or a part of the steps of the methods described in the various examples of the present invention. The storage medium includes: a USB flash disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk and another medium that can store program codes.

[0062] Logics and/or steps expressed in the flow chart or otherwise described herein, for example, may be considered as a sequence table of executable instructions for implementing logical functions, and may be implemented in any computer-readable medium for use by instruction execution systems, apparatuses, or devices (such as computer-based systems, systems including processors, or other systems that may acquire instructions from the instruction execution systems, the apparatuses, or the devices and execute the instructions), or in a combination manner. For the purposes of the specification, computer-readable medium can be any device that can contain, store, communicate, propagate or transmit programs for execution by an instruction-executing system, device or equipment, or in combination with these instructions for execution by such a system, device or equipment.

[0063] More specific examples (non-exhaustive list) of the computer-readable medium may include the following: an electrical connection (an electronic apparatus) with one or more wires, a portable computer disk case (a magnetic apparatus), a Random Access Memory (RAM), a Read-Only Memory (ROM), an Erasable Programmable Read-Only Memory (EPROM or flash memory), an optical fiber, and a portable Compact Disk Read-Only Memory (CDROM). Furthermore, the computer-readable medium can even be paper or other suitable medium on which the program can be printed, because the program can be obtained in electronic form by, for example, scanning the paper or other medium optically, then editing, interpreting or processing as necessary or in other appropriate ways, and then storing in the computer memory.

[0064] It should be understood that, each part of the present invention may be realized by hardware, software, firmware or a combination thereof. In the above implementation manners, a plurality of steps or methods may be realized by software or firmware stored in the memory and executed by the appropriate instruction execution systems. For example, if the plurality of steps or methods are realized by hardware, as in another implementation manner, the plurality of steps or methods may be realized by any one of the following technologies which are well known in the art or a combination thereof: a discrete logic circuit with a logic gate circuit for realizing a logic function for a data signal, an application-specific integrated circuit with an appropriate combinational logic gate circuit, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

Embodiment 4

[0065] Referring to FIG. 4-7, as an embodiment of the present invention, an InSAR-based measurement method for angle of critical deformation in a coal mining area is provided. To verify the beneficial effects of the present invention, scientific arguments are made through economic benefit calculations and simulation experiments.

[0066] The present invention overcomes the drawback that the parameters of mining subsidence parameters can only be obtained through ground monitoring stations or actual measurements. The method based on the integration of SBAS-InSAR technology and the probability integral method can obtain the mining subsidence parameters quickly and accurately.

[0067] As shown in FIGS. 4 to 7, the InSAR-based measurement method and system for angle of critical deformation in the coal mining area provided by the present invention, includes setting 128 monitoring points along the strike and dip profiles of the coal seam, carrying out two-dimensional decomposition on data on each monitoring point, calculating three critical deformation curves, and finally, by combining the two corresponding geological profiles drawn with Rhino6, and considering the subsidence curves, the three critical deformation curves, and the geological profiles, obtaining corresponding angle of critical deformation in the mountainous coal mining area according to mining subsidence data, under the condition of single coal seam mining, the strike movement angles are 48.96 and 54.07, and the dip angles of critical deformation are 67.66 and 61.56 respectively.

[0068] It should be noted that the above examples are merely used to explain the technical solutions of the present disclosure and not intended to limit the present disclosure. Although the present disclosure is described in detail with reference to the preferred examples, those of ordinary skill in the art should understand that they can make modifications or equivalent substitutions to the technical solutions of the present disclosure without departing from the spirit and scope of the technical solutions of the present disclosure. These modifications or equivalent substitutions should fall within the scope of the claims of the present disclosure.

InSAR-based Measurement Method for Angle of Critical Deformation in Coal Mining Area and System

Inventors

Cpc classification

Classification Explorer

G01S13/9023

PHYSICS

Classification Explorer

G01S13/9094

PHYSICS

International classification

Classification Explorer

G01S13/90

PHYSICS

Abstract

Claims

Description