Method for predicting dynamic water inflow of working face based on water inflow characteristics of borehole

Abstract

The application discloses a working face dynamic water inrush amount prediction method based on a borehole water outflow feature, and steps include: 1) selecting adjacent mined working faces and counting actual water inrush amount, final hole water amount and final hole water pressure; 2) counting and drawing a curve of total water inrush amount along with footage; drawing final hole water amount and final hole water pressure contour lines, and extracting final hole water amount and final hole water pressure curves along with footage along a central trend of a working face to be mined; 3) performing curve fitting to obtain fitting equations of total water inrush amount, final hole water amount and final hole water pressure; 4) performing section division on the working face to be mined, monitoring and counting borehole water amount and borehole water pressure; 5) drawing borehole water amount and borehole water pressure contour line maps of the working face to be mined, and extracting final hole water amount and final hole water pressure curves along with footage along a central trend of the working face to be mined; 6) calculating total water inrush amount in different sections of the working face to be mined; and 7) obtaining water inrush amount prediction curves varying with mining footage. The method is accurate in prediction results.

Description

Technical Field

[0001] This invention belongs to the field of mine water control technology, and relates to a method for predicting dynamic water inflow in working faces based on borehole water discharge characteristics. Background Technology

[0002] Accurate and timely prediction of mine water inflow is crucial for mine water hazard prevention. Currently, there are two main methods for predicting mine water inflow: analytical methods and analogical methods. Analytical methods, primarily including the large-shaft method and the gallery method, predict mine water inflow mainly by obtaining indirect parameters such as the unit width flow rate of the working face, hydraulic gradient, and the thickness of the overlying aquifer. However, in reality, geological conditions vary across different mining areas, and this method often fails to reflect these differences, and the parameters used may not accurately reflect regional characteristics.

[0003] Another method for predicting mine water inflow is the analogy method. This method is based on the assumption that the target working face and adjacent mined working faces have similar geological conditions and working face layouts. The water volume of the target working face is inferred from the measured water volume of the mined working face. Compared with the analytical method, this method avoids errors caused by differences in geological conditions between different mining areas. However, the analogy only uses the total water volume of the mined working faces, which cannot show the influence of water-rich areas on the water inflow.

[0004] Therefore, it is particularly necessary to explore a method to overcome the above-mentioned defects and develop a method for predicting mine water inflow, so as to provide a reliable basis for the prevention and control of mine water hazards. Summary of the Invention

[0005] The purpose of this invention is to provide a dynamic water inflow prediction method for working faces based on borehole water production characteristics, which solves the problems of insufficient targeting, large data processing volume, and insufficient accuracy and reliability of existing mine water inflow prediction methods.

[0006] The technical solution adopted in this invention is a method for predicting dynamic water inflow at a working face based on borehole water discharge characteristics, implemented according to the following steps:

[0007] Step 1: Select the existing working face adjacent to the working face to be mined, and count the actual water inflow, the final water volume of the drainage hole, and the final water pressure of the existing working face;

[0008] Step 2: Divide the mining footage into segments, count the total water inflow of the mined working face in each segment, and plot the curve of the total water inflow as a function of the mining footage; use GIS information to plot the contour lines of the final hole water volume and final hole water pressure, and combine the segmented mining footage data to extract the curves of the final hole water volume and final hole water pressure as a function of the mining footage along the middle of the working face to be mined.

[0009] Step 3: Perform curve fitting on all data of total water inflow, final borehole water volume, and final borehole water pressure at the end of the mining advance to obtain the fitting equation between total water inflow and final borehole water volume and final borehole water pressure.

[0010] Step 4: Divide the working face to be mined into sections and count the final water volume and pressure of the drainage hole at the working face to be mined.

[0011] Step 5: Draw contour maps of the final drainage water volume and final drainage water pressure of the working face to be mined, and combine them with the advance data to extract the curves of the final drainage water volume and final drainage water pressure as a function of the advance along the middle of the working face to be mined.

[0012] Step 6: Based on the principle of similarity, using the final borehole water volume and final borehole water pressure of the working face to be mined as independent variables, the total inflow of water in different sections of the working face to be mined is calculated by using a fitting equation.

[0013] Step 7: Use cumulative calculation to obtain the predicted water inflow curve as the mining depth changes.

[0014] The beneficial effects of this invention are as follows: Based on the similarity in geological conditions and working face layout between the target working face and adjacent mined working faces, a comparative method is used to infer the water volume of the target working face from the measured water volume of the mined working face. This method considers the differences in water-bearing capacity of the target working face in different areas, divides the mined working face into sections, and divides the working face into equidistant areas along the strike. Water inflow curves are plotted using measured water inflow, and final borehole water inflow and pressure curves are plotted using final borehole water inflow and pressure curves. Correlation analysis is performed on the curves to obtain proportionality coefficients and fit equations. The target working face is then divided into sections with the same division distance as the mined working face. Finally, the final borehole water inflow curve is plotted using the measured final borehole water inflow and pressure data of the target working face, and correlation is analyzed. Finally, the analysis results of the target and mined working faces are combined to calculate and predict the water inflow of the target working face. Attached Figure Description

[0015] Figure 1 This is a schematic flowchart of the method of the present invention;

[0016] Figure 2 This is a bar graph showing the final water inflow and water pressure of the MKQ-4 working face top plate drainage borehole according to an embodiment of the present invention.

[0017] Figure 3 This is a curve showing the total water inflow rate of the MKQ-4 working face as a function of the advance, according to an embodiment of the present invention.

[0018] Figure 4a These are the contour lines of the final borehole water volume of the MKQ-4 working face in this embodiment of the invention; Figure 4b These are the contour lines of the final borehole water pressure of the MKQ-4 working face in this embodiment of the invention;

[0019] Figure 5a This is a curve showing the change in water volume at the final hole depth of the MKQ-4 working face as a function of the advance length, according to an embodiment of the present invention. Figure 5b This is the curve showing the change in water pressure at the final hole depth of the MKQ-4 working face as a function of the advance length, according to an embodiment of the present invention.

[0020] Figure 6 This is a comparison between the measured and predicted water volume at the MKQ-5 working face in an embodiment of the present invention.

[0021] Figure 7 This is a bar chart of the final hole water volume of the MKQ-5 working face according to an embodiment of the present invention, and a comparison chart of the measured and predicted water volume. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] Reference Figure 1 The prediction method of the present invention is implemented according to the following steps:

[0024] Step 1: Select the existing working face adjacent to the working face to be mined, and count the actual water inflow, the final water volume of the drainage hole, and the final water pressure of the existing working face (the full names of the final water volume and the final water pressure are the final water volume of the borehole and the final water pressure of the borehole, respectively).

[0025] Before predicting the water inflow of the working face to be mined, a previously mined working face that can be used for comparison is selected, and then the relevant parameters measured from the previously mined working face are obtained.

[0026] Step 2: Divide the mining footage into segments, count the total water inflow of the mined working face in each segment, and plot the curve of the total water inflow as a function of the mining footage; use GIS information to plot the contour lines of the final hole water volume and final hole water pressure, and combine the segmented mining footage data to extract the curves of the final hole water volume and final hole water pressure as a function of the mining footage along the middle of the working face to be mined.

[0027] The segmented monitoring of water inflow data differs from the overall monitoring of the mined working face. After dividing the working face to be mined into segments, the actual water inflow, final hole water volume, final hole water pressure, and other data obtained from the monitoring are divided according to the same length interval D. After the division, the curves of final hole water pressure, final hole water volume, and water inflow are plotted, and the corresponding interval of the mining advance S is D, which makes it easier to reflect the regional water-bearing characteristics of the working face to be mined.

[0028] Step 3: Perform curve fitting on all data of total water inflow, final borehole water volume, and final borehole water pressure at the end of the mining advance to obtain the fitting equation between total water inflow and final borehole water volume and final borehole water pressure.

[0029] After obtaining relevant data from the working face for fitting reference, the actual water inflow curve and the final borehole water volume and final borehole water pressure curve are plotted using this data. Then, correlation analysis is performed on the curves to obtain the proportional coefficient.

[0030] Step 4: Divide the working face to be mined into sections and count the final water volume and pressure of the drainage hole at the working face to be mined.

[0031] When predicting the water inflow of the working face to be mined, the working face is first divided into sections of length D, and then monitored in sections to obtain data on the final water volume and final water pressure of the drainage hole.

[0032] Step 5: Draw contour maps of the final drainage water volume and final drainage water pressure of the working face to be mined, and combine them with the advance data to extract the curves of the final drainage water volume and final drainage water pressure as a function of the advance along the middle of the working face to be mined.

[0033] The data obtained from monitoring the working face to be mined is used to draw contour maps of the final hole water volume and final hole water pressure of the working face to be mined. Then, the curves of the change of the final hole water volume and final hole water pressure with the advance are extracted along the middle of the working face.

[0034] Step 6: Based on the principle of similarity, using the final borehole water volume and final borehole water pressure of the working face to be mined as independent variables, the total inflow of water in different sections of the working face to be mined is calculated by using a fitting equation.

[0035] The predicted total water inflow needs to be combined with the equation fitted from the already mined working face. The correlation coefficients in the equation remain unchanged. The mining footage S and the final water volume Q are calculated at intervals of section length D. 终 Final water pressure P 终 The independent variable is denoted by , and the total inflow Q is the dependent variable.

[0036] Step 7: Use cumulative calculation to obtain the predicted water inflow curve as the mining depth changes;

[0037] The water inflow of the working face to be mined is calculated by comparing the parameters obtained from the correlation analysis of the mined working face and the working face to be mined.

[0038] Example 1

[0039] Taking the MKQ-4 working face of a mine in the Mengshan mining area as an example, the mine water inflow was predicted for the entire year of 2020. During the mining operation, the mine water inflow increased significantly, and the records for the total water inflow, final borehole water volume, and final borehole water pressure are comprehensive. Therefore, conducting water inflow prediction based on borehole water characteristics for this mine has good explanatory value.

[0040] An embodiment of the method of the present invention is implemented according to the following steps:

[0041] Step 1: Select the existing working face adjacent to the working face to be mined, and count the actual water inflow, the final water volume of the drainage hole, and the final water pressure of the existing working face.

[0042] Step 2: Divide the mining footage into segments, calculate the total water inflow in each segment, and plot a curve showing the total water inflow as a function of the mining footage. Use GIS information to plot contour lines for the final borehole water volume and pressure. Combine this with the segmented mining footage data to extract curves showing the final borehole water volume and pressure as a function of the mining footage along the strike of the middle of the mined face.

[0043] If the length of the section of the MKQ-4 working face is 100m, then when plotting the curves of each parameter change with the advance, the advance interval is 100m. Figure 2 This is a construction drawing of the MKQ-4 working face top plate drainage drilling according to an embodiment of the present invention; Figure 2 This is a bar graph showing the final water inflow and water pressure of the MKQ-4 working face top plate drainage borehole according to an embodiment of the present invention. Figure 3 The curve showing the total water inflow at the MKQ-4 working face as a function of the advance; Figure 4a , Figure 4b These are the contour lines for the final borehole water volume and final borehole water pressure at the working face. Figure 5a , Figure 5b The figures show the curves of the final hole water volume and final hole water pressure as a function of the advance, extracted along the middle of the working face.

[0044] Step 3: Perform curve fitting on all data of total water inflow, final borehole water volume, and final borehole water pressure at the end of the mining advance to obtain the fitting equation between total water inflow and final borehole water volume and final borehole water pressure.

[0045] After obtaining relevant data from the MKQ-4 working face, the actual water inflow curve and the curves showing the changes in final borehole water volume and final borehole water pressure were plotted. Correlation analysis was then performed on these curves to obtain the correlation coefficient, and subsequently, the predicted water inflow equation was derived.

[0046] Q = Q 终 *(-2.551)+P 终 *(-102.065)+288.413+S*0.297

[0047] Where Q is the total inflow;

[0048] Q 终 This represents the final water volume at the orifice.

[0049] P 终 The final borehole water pressure;

[0050] S represents the mining footage.

[0051] Step 4: Divide the MKQ-5 working face into sections and count the final drainage water volume and final drainage water pressure of the working face.

[0052] The data on the final drainage volume and pressure of the MKQ-4 working face were used to predict its inflow, and compared with the actual inflow, as shown in Table 1.

[0053] Table 1. Statistics on final water volume and final water pressure of the MKQ-5 working face in Example 1

[0054] Z11-2 5 1 Z11-1 4.5 1.2 H9-1 5 1 H9-2 6 1.2 H9-3 5 1 H9-4 5.5 1 Z8-1 4.5 1.2 Z8-2 3.5 1 H7-1 5 1.2 H7-2 5.5 1.3 H7-3 5 1.1 Z6-1 5 1.1 Z6-2 4 1.1 Z6-3 3 0.8

[0055] Step 5: Draw contour maps of the final drainage water volume and final drainage water pressure of the working face to be mined, and combine them with the advance data to extract the curves of the final drainage water volume and final drainage water pressure as a function of the advance along the middle of the working face to be mined.

[0056] Using data from the monitoring of the MKQ-4 working face, contour maps of the final drainage water volume and pressure were plotted. Curves showing the variation of final drainage water volume and pressure with drilling depth were also extracted along the central strike of the MKQ-4 working face. The resulting contour maps and curves are shown below. Figure 4a , Figure 4b , Figure 5a , Figure 5b .

[0057] Step 6: Based on the principle of similarity, using the final borehole water volume and final borehole water pressure of the working face to be mined as independent variables, calculate the total water inflow in different sections of the working face to be mined using a fitting equation.

[0058] Q = Q 终 *(-2.551)+P 终 *(-102.065)+288.413+S*0.297

[0059] Where Q is the total inflow;

[0060] Q 终 This represents the final water volume at the orifice.

[0061] P 终 The final borehole water pressure;

[0062] S represents the mining footage.

[0063] Substituting the final borehole water volume, final borehole water pressure, and mining advance parameters into the equation, the predicted total water inflow Q can be obtained. The predicted water inflow under different advances is shown in Table 2.

[0064] Table 2. Prediction results of water inflow at different advances in the MKQ-4 working face in Example 1.

[0065]

[0066] Step 7: Use cumulative calculation to obtain the predicted water inflow curve as the mining depth changes.

[0067] Reference Figure 6 and Figure 7 The predicted water volume curve was compared with the measured water volume curve at the working face. The two curves showed a good correlation, indicating that the prediction results of the method of the present invention are relatively accurate. The method of the present invention is obviously feasible and the data is reliable.

[0068] Example 2

[0069] Taking the MKQ-4 working face of a mine in the Mengshan mining area as an example, the mine water inflow was predicted for the entire year of 2020. During the mining operation, the mine water inflow increased significantly, and the records for the total water inflow, final borehole water volume, and final borehole water pressure are comprehensive. Therefore, conducting water inflow prediction based on borehole water characteristics for this mine has good explanatory value.

[0070] An embodiment of the method of the present invention is implemented according to the following steps:

[0071] Step 1: Select the existing working face adjacent to the working face to be mined, and count the actual water inflow, the final water volume of the drainage hole, and the final water pressure of the existing working face.

[0072] Step 2: Divide the mining footage into segments, calculate the total water inflow in each segment, and plot a curve showing the total water inflow as a function of the mining footage. Use GIS information to plot contour lines for the final borehole water volume and pressure. Combine this with the segmented mining footage data to extract curves showing the final borehole water volume and pressure as a function of the mining footage along the strike of the middle of the mined face.

[0073] If the length of the section of the MKQ-4 working face is 100m, then when plotting the curves of each parameter change with the advance, the advance interval is 100m. Figure 2 This is a construction drawing of the MKQ-4 working face top plate drainage drilling according to an embodiment of the present invention; Figure 2 This is a bar graph showing the final water inflow and water pressure of the MKQ-4 working face top plate drainage borehole according to an embodiment of the present invention. Figure 3 The curve showing the total water inflow at the MKQ-4 working face as a function of the advance; Figure 4a , Figure 4b These are the contour lines for the final borehole water volume and final borehole water pressure at the working face. Figure 5a , Figure 5b The figures show the curves of the final hole water volume and final hole water pressure as a function of the advance, extracted along the middle of the working face.

[0074] Step 3: Perform curve fitting on all data of total water inflow, final borehole water volume, and final borehole water pressure at the end of the mining advance to obtain the fitting equation between total water inflow and final borehole water volume and final borehole water pressure.

[0075] After obtaining relevant data from the MKQ-4 working face, the actual water inflow curve and the curves showing the changes in final borehole water volume and final borehole water pressure were plotted. Correlation analysis was then performed on these curves to obtain the correlation coefficient, and subsequently, the predicted water inflow equation was derived.

[0076] Q = Q 终 *(-2.551)P 终 *(-102.065)+288.413+S*0.297

[0077] Where Q is the total inflow;

[0078] Q 终 This represents the final water volume at the orifice.

[0079] P 终 The final borehole water pressure;

[0080] S represents the mining footage.

[0081] Step 4: Divide the MKQ-5 working face into sections and count the final drainage water volume and final drainage water pressure of the working face.

[0082] The final drainage volume and pressure data of the MKQ-4 working face were used to predict its inflow, and compared with the actual inflow, as shown in Table 3.

[0083] Table 3. Statistics on final borehole water volume and final borehole water pressure of the MKQ-5 working face in Example 2.

[0084] H6-1 3.5 1 H6-2 5 1.1 H6-3 4.5 1 H6-4 5 1.2 H5-1 2.5 1 H5-2 5 1 H5-3 5 1 H5-4 5.5 1 Z4-1 4 1 Z4-2 4.5 1 Z4-3 2.5 1 H4-1 12 1.6 H4-2 9 1.4 H4-3 8 1.5 H4-4 10 1.6

[0085] Step 5: Draw contour maps of the final drainage water volume and final drainage water pressure of the working face to be mined, and combine them with the advance data to extract the curves of the final drainage water volume and final drainage water pressure as a function of the advance along the middle of the working face to be mined.

[0086] Using data from the monitoring of the MKQ-4 working face, contour maps of the final drainage water volume and pressure were plotted. Curves showing the variation of final drainage water volume and pressure with drilling depth were also extracted along the central strike of the MKQ-4 working face. The resulting contour maps and curves are shown below. Figure 4a , Figure 4b , Figure 5a , Figure 5b .

[0087] Step 6: Based on the principle of similarity, using the final borehole water volume and final borehole water pressure of the working face to be mined as independent variables, calculate the total water inflow in different sections of the working face to be mined using a fitting equation.

[0088] Q = Q 终 *(-2.551)+P 终*(-102.0650+288.413+S*0.297

[0089] Where Q is the total inflow;

[0090] Q 终 This represents the final water volume at the orifice.

[0091] P 终 The final borehole water pressure;

[0092] S represents the mining footage.

[0093] Substituting the final borehole water volume, final borehole water pressure, and mining advance parameters into the equation, the predicted total water inflow Q can be obtained. The predicted water inflow under different advances is shown in Table 4.

[0094] Table 4. Prediction results of water inflow at different advances in the MKQ-4 working face in Example 2.

[0095]

[0096] Step 7: Use cumulative calculation to obtain the predicted water inflow curve as the mining depth changes.

[0097] Reference Figure 6 and Figure 7 The predicted water volume curve was compared with the measured water volume curve at the working face. The two curves showed a good correlation, indicating that the prediction results of the method of the present invention are relatively accurate. The method of the present invention is obviously feasible and the data is reliable.

[0098] Example 3

[0099] Taking the MKQ-4 working face of a mine in the Mengshan mining area as an example, the mine water inflow was predicted for the entire year of 2020. During the mining operation, the mine water inflow increased significantly, and the records for the total water inflow, final borehole water volume, and final borehole water pressure are comprehensive. Therefore, conducting water inflow prediction based on borehole water characteristics for this mine has good explanatory value.

[0100] An embodiment of the method of the present invention is implemented according to the following steps:

[0101] Step 1: Select the existing working face adjacent to the working face to be mined, and count the actual water inflow, the final water volume of the drainage hole, and the final water pressure of the existing working face.

[0102] Step 2: Divide the mining footage into segments, calculate the total water inflow in each segment, and plot a curve showing the total water inflow as a function of the mining footage. Use GIS information to plot contour lines for the final borehole water volume and pressure. Combine this with the segmented mining footage data to extract curves showing the final borehole water volume and pressure as a function of the mining footage along the strike of the middle of the mined face.

[0103] If the length of the section of the MKQ-4 working face is 100m, then when plotting the curves of each parameter change with the advance, the advance interval is 100m. Figure 2 This is a construction drawing of the MKQ-4 working face top plate drainage drilling according to an embodiment of the present invention; Figure 2 This is a bar graph showing the final water inflow and water pressure of the MKQ-4 working face top plate drainage borehole according to an embodiment of the present invention. Figure 3 The curve showing the total water inflow at the MKQ-4 working face as a function of the advance; Figure 4a , Figure 4b These are the contour lines for the final borehole water volume and final borehole water pressure at the working face. Figure 5a , Figure 5b The figures show the curves of the final hole water volume and final hole water pressure as a function of the advance, extracted along the middle of the working face.

[0104] Step 3: Perform curve fitting on all data of total water inflow, final borehole water volume, and final borehole water pressure at the end of the mining advance to obtain the fitting equation between total water inflow and final borehole water volume and final borehole water pressure.

[0105] After obtaining relevant data from the MKQ-4 working face, the actual water inflow curve and the curves showing the changes in final borehole water volume and final borehole water pressure were plotted. Correlation analysis was then performed on these curves to obtain the correlation coefficient, and subsequently, the predicted water inflow equation was derived.

[0106] Q = Q 终 *(-2.551)P 终 *(-102.065)+288.413+S*0.297

[0107] Where Q is the total inflow;

[0108] Q 终 This represents the final water volume at the orifice.

[0109] P 终 The final borehole water pressure;

[0110] S represents the mining footage.

[0111] Step 4: Divide the MKQ-5 working face into sections and count the final drainage water volume and final drainage water pressure of the working face.

[0112] The data on the final drainage volume and pressure of the MKQ-4 working face were used to predict its inflow, and compared with the actual inflow, as shown in Table 5.

[0113] Table 5. Statistics on final borehole water volume and final borehole water pressure of the MKQ-5 working face in Example 3.

[0114] H3-1 10 1.4 H3-2 9 1.3 H3-3 9 1.4 H3-4 9 1.4 Z2-1 8.5 1.5 Z2-2 7 1.3 H2-1 8 1.4 H2-2 7.5 1.4 Z1-1 5 1 Z1-2 5.5 1 H1-1 12 1.4 H1-2 18 1.4 H1-3 0 0 H1-4 5.5 1.4 H1-5 5 1.4

[0115] Step 5: Draw contour maps of the final drainage water volume and final drainage water pressure of the working face to be mined, and combine them with the advance data to extract the curves of the final drainage water volume and final drainage water pressure as a function of the advance along the middle of the working face to be mined.

[0116] Using data from the monitoring of the MKQ-4 working face, contour maps of the final drainage water volume and pressure were plotted. Curves showing the variation of final drainage water volume and pressure with drilling depth were also extracted along the central strike of the MKQ-4 working face. The resulting contour maps and curves are shown below. Figure 4a , Figure 4b , Figure 5a , Figure 5b .

[0117] Step 6: Based on the principle of similarity, using the final borehole water volume and final borehole water pressure of the working face to be mined as independent variables, calculate the total water inflow in different sections of the working face to be mined using a fitting equation.

[0118] Q = Q 终 *(-2.551)P 终 *(-102.065)+288.413+S*0.297

[0119] Where Q is the total inflow;

[0120] Q 终 This represents the final water volume at the orifice.

[0121] P 终 The final borehole water pressure;

[0122] S represents the mining footage.

[0123] Substituting the final borehole water volume, final borehole water pressure, and mining advance parameters into the equation, the predicted total water inflow Q can be obtained. The predicted water inflow under different advances is shown in Table 6.

[0124] Table 6. Prediction results of water inflow at different advances in the MKQ-4 working face in Example 3.

[0125]

[0126] Step 7: Use cumulative calculation to obtain the predicted water inflow curve as the mining depth changes.

[0127] Reference Figure 6 and Figure 7 The predicted water volume curve was compared with the measured water volume curve at the working face. The two curves showed a good correlation, indicating that the prediction results of the method of the present invention are relatively accurate. The method of the present invention is obviously feasible and the data is reliable.

Claims

1. A method for predicting dynamic water inflow at a working face based on borehole water production characteristics, characterized in that, The steps include: Step 1: Statistically calculate the actual water inflow, drainage water volume at the final hole, and final hole water pressure of adjacent mined working faces; Step 2: Plot the curve of total water inflow as a function of drilling footage; plot the contour lines of final hole water volume and final hole water pressure, and extract the curves of final hole water volume and final hole water pressure as a function of drilling footage; Step 3: Obtain the fitting equation between the total water inflow and the final hole water volume and final hole water pressure; Step 4: Divide the working face to be mined into sections, and statistically calculate the drainage water volume and final hole water pressure at the final hole; Step 5: Plot the contour lines of the drainage water volume and final hole water pressure of the working face to be mined, and extract the curves of final hole water volume and final hole water pressure as a function of drilling footage along the central strike of the working face to be mined; Step 6: Calculate the total water inflow in different sections of the working face to be mined using the fitting equation; Step 7: Obtain the predicted curve of water inflow as a function of drilling footage.

2. The method for predicting dynamic water inflow at a working face based on borehole water production characteristics according to claim 1, characterized in that, Step 2, the specific process is as follows: The mining footage is divided into segments, and the total water inflow of the mined working face in each segment is counted. A curve showing the total water inflow as a function of the mining footage is plotted. Contour lines of final hole water volume and final hole water pressure are plotted using GIS information. Combined with the segmented mining footage data, curves showing the change of final hole water volume and final hole water pressure as a function of the mining footage are extracted along the middle of the working face to be mined. The segmented monitoring of water inflow data differs from the overall monitoring of the mined working face. After dividing the working face to be mined into segments, the actual water inflow, final hole water volume, and final hole water pressure data obtained from the monitoring are divided according to the same length interval D. After the division, the curves of final hole water pressure, final hole water volume, and water inflow are plotted, and the corresponding interval of the mining advance S is D, which makes it easier to reflect the regional water-bearing characteristics of the working face to be mined.

3. The method for predicting dynamic water inflow at a working face based on borehole water production characteristics according to claim 1, characterized in that, Step 3, the specific process is as follows: Curve fitting was performed on all data at the end of the mining advance, including total water inflow, final borehole water volume, and final borehole water pressure, to obtain the fitting equation between total water inflow and final borehole water volume and pressure. The expression of the fitting equation is as follows: Q=Q 终 *(-2.551)+P 终 *(-102.065)+288.413+S*0.297 Where Q is the total inflow; Q 终 P represents the final water volume at the well. 终 is the final borehole water pressure; S is the drilling footage.

4. The method for predicting dynamic water inflow at a working face based on borehole water production characteristics according to claim 1, characterized in that, Step 6 involves the following specific steps: Based on the principle of similarity, the final borehole water volume and final borehole water pressure of the working face to be mined are used as independent variables, and the total water inflow in different sections of the working face to be mined is calculated by using a fitting equation. The predicted total water inflow needs to be combined with the equation fitted from the already mined working face. The correlation coefficients in the equation remain unchanged. The mining footage S and the final water volume Q are calculated at intervals of section length D. 终 Final water pressure P 终 The independent variable is denoted by , and the total inflow Q is the dependent variable.

5. The method for predicting dynamic water inflow at a working face based on borehole water production characteristics according to claim 1, characterized in that, Step 7 involves the following specific steps: By using cumulative calculation, the water inflow of the working face to be mined is obtained by comparing the parameters obtained from the correlation analysis of the mined working face and the working face to be mined.

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