A method of constructing a drill hole in a heading face

Abstract

The application discloses a kind of tunneling working face construction drilling methods, it is related to mine geological disaster prevention, mining technology and safety production management technical field;Including the following steps: normal area is drilled and is operated step S1, 4 drill holes are arranged each time, wherein center hole 2, left and right two holes two, center hole length is 90 meters, left and right two hole hole depth 92.8 meters, center hole terminal hole respectively controls the roof, floor of coal seam, two hole is arranged in coal seam, roadway side hole terminal hole position is 20 meters from tunneling roadway side;Before starting, using the geological work result of mining area already, geological exploration report, the drawing of material report result report, report preparation tunneling working face geological specification, draw tunneling working face prediction profile, according to the characteristics of each item of abnormal geological body, master tunneling working face front coal rock layer occurrence and change trend, accurately master and determine construction horizon, reasonably design roadway tunneling slope.

Description

Technical Field

[0001] This invention relates to the fields of mine geological disaster prevention and control, mining technology and safety production management, specifically a drilling method for tunneling face structure. Background Technology

[0002] In recent years, with the Party and the State placing increasing emphasis on safe production and respect for life, a series of powerful measures have been taken to free miners from the arduous and inefficient labor that had long plagued their lives and safety, enabling them to live a decent and dignified life. With the significant increase in the mechanization, informatization, intelligence, and automation of mines, the requirements for the accuracy of identifying geological conditions in mines are also becoming increasingly stringent. To meet the needs of modern, efficient, and high-yield production, accurately identifying abnormal and concealed geological structures ahead of the tunneling face is becoming increasingly important for safe and efficient mine production. However, there are almost no systematic reports on relatively accurate advanced geological condition prediction techniques in China, and even fewer related application cases. Especially for concealed structures in development and tunneling faces, accurately identifying abnormal and concealed geological structures ahead of the tunneling face is extremely urgent and necessary.

[0003] Currently, underground drilling mainly focuses on identifying goafs or water bodies at the tunneling face to eliminate the threat of water hazards. However, there are very few technical standards and specifications for investigating hidden structures and minor geological formations ahead of the tunneling face that could affect production. All exploration efforts are primarily aimed at determining the presence of water bodies or goafs ahead, with the goal of identifying and eliminating water hazards and abnormal gases such as methane in the coal seam. Underground geophysical exploration mainly employs transient electromagnetic instrument detection technology and direct current technology to predict and forecast the geological conditions ahead of the tunneling face. However, the accuracy of these methods is not high, and they are significantly affected and interfered with by factors such as water seepage from the underground roof, electrical equipment, power cables, tunneling machines, conveyors, and metal components like anchor bolts and anchor cable mesh. Different operators, equipment, detection methods, and operational procedures can lead to significant differences in the results and conclusions for the same geological body or phenomenon. Furthermore, the application conditions and scope of various detection methods differ, and even for the same geological body, multiple interpretations are possible. The results regarding the occurrence and structural anomalies of coal (rock) ore bodies ahead of the tunneling face still have many limitations, and lack guidance for safe and rapid tunneling. Currently, a relatively systematic and accurate method for predicting geological structures in underground coal mines is still under exploration. Therefore, in view of the current deficiencies and needs of advanced detection technology for concealed geological structures ahead of tunneling faces in underground coal mines, it is urgent to develop a comprehensive, systematic, efficient, accurate, and rapid method for advanced detection of abnormal geological structures ahead of tunneling faces. To this end, we propose a tunneling face structural drilling method to solve the above problems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a drilling method for constructing tunneling faces, thereby solving the problems mentioned in the background section.

[0005] To achieve the goal of conducting advanced detection of abnormal geological structures ahead of the tunneling face through the comprehensive application of geophysical exploration, drilling, and geochemical exploration methods, accurately identifying the location and extent of such structures, ensuring safe, rapid, and efficient tunneling, improving the single-advance level of the tunneling face, alleviating the pressure and safety risks caused by the tight connection between mining and tunneling, and creating favorable conditions for safe production in the mine, this invention provides the following technical solution: a tunneling face structure drilling method, comprising the following steps:

[0006] Normal drilling operation steps S1: Each drilling operation involves 4 boreholes, including 2 central boreholes and 2 side boreholes on the left and right sides. The central boreholes are 90 meters long and the side boreholes are 92.8 meters deep. The central boreholes control the top and bottom of the coal seam respectively. The side boreholes are located in the coal seam. The end of the side boreholes is 20 meters away from the side of the tunnel.

[0007] S2. Based on the elevations of the top and bottom of the coal seam in the excavated roadway and the elevations of the top and bottom of the coal seam at the drilling location, and the distance between the two points, calculate the slope of the top and bottom of the coal seam in the excavated roadway.

[0008] S3. Based on the elevation and slope of the top and bottom plates at the drilling location, infer the elevation of the top plate of the coal seam within the drilling range ahead, and draw the predicted coal seam profile.

[0009] S4. Conduct drilling design. The drilling location is B. The height of the drilling rig is 2m above the center axis of the drilling rig. The elevation of the center axis of the drilling rig is 896.79m. The drilling depth is 90m. Based on the drilling depth and slope, the elevation of the top plate of the coal seam at the final drilling location is 893.92m and the elevation of the bottom plate is 890.42m.

[0010] S5. Regarding the design of the sidewall boreholes, to ensure the final borehole position meets specifications, the final borehole position is 20m from the two roadway sides, and its projection length on the roadway centerline is 90m. The borehole length is... The angle between the hole and the center hole is arctg(22.5 / 90) = 14°02′. Based on the distance between the two side holes and the angle between the two side holes and the center hole, the positions of the final holes c2 and c3 of the two side holes can be uniquely determined. Based on the modified coal seam floor contour map, the elevation of the coal seam top and bottom plates is obtained by interpolation.

[0011] S6. The Geodetic Surveying Department will calibrate the parameters of the four boreholes on-site. During drilling, a geological personnel will make original records of all drilling activities. Drilling will proceed in sequence from the calibrated central boreholes C1 and C4, to the left side borehole C2 and the right side borehole C3.

[0012] A drilling method for constructing a tunneling face, which may also include the following steps:

[0013] The drilling steps in the abnormal area are as follows: S7. The roof elevation at drilling location C is 896.82m. The slope of the excavated roadway at drilling location C is 3°18′. Based on the length and slope, it can be preliminarily inferred that the final coal seam elevation at the borehole is 891.63m, the floor elevation is 888.13m, the height between the central axis of the drilling rig and the roof is 2m, and the elevation at the central axis of the drilling rig is 894.82m.

[0014] The inclination angles of S8 and the left and right side holes are determined based on the top and bottom plate elevations of the final hole location. The elevations of the top and bottom plates of the coal seam are obtained by interpolation. The bottom plate elevation of the final hole d2 is 889.1m, and the expected borehole elevation in the coal seam is 890.8m. The inclination angle of the borehole is θ = arctg(4.02 / 92.77) = 2°28′.

[0015] The bottom elevation of the d3 final borehole is 889.6m, the expected borehole elevation in the coal seam is 891.3m, and the borehole inclination angle is θ=arctg(3.52 / 92.77)=2°10′;

[0016] S9. According to the drilling design, the geological surveying technicians will mark the opening parameters in sequence and carry out drilling. When drilling reaches 34.5m, the drilling stratum changes. Based on the drilling speed on site and the size of the rock cuttings in the backwater, the stratum of the borehole can be preliminarily determined. Continue drilling forward to the design position and collect and organize the original data.

[0017] To further optimize this technical solution, in step S1, when there are no abnormalities in the geophysical drilling, a safety distance of 30 meters is designed to be left in front and a safety distance of 20 meters is left on both sides of the tunnel. Each drilling operation is 90 meters long, and the next drilling operation is carried out after 60 meters of excavation.

[0018] To further optimize this technical solution, in step S2, the elevation of point A at a certain distance from the drilling location is 903.05m, the elevation of point B at the drilling location is 898.79m, the elevation difference between points A and B is 4.26m, and the distance is 73.78m. The slope between A and B can be calculated as: θ=arctg(4.26 / 73.78)=3°18′.

[0019] To further optimize this technical solution, in step S4, the design of the drilling center hole should theoretically be controlled at the top and bottom plate of the coal seam based on the final hole position, and the inclination angle of the borehole should be calculated based on the elevation of the machine center axis and the elevation of the final hole position.

[0020] For example, if the central borehole C1 controls the roof, its final borehole elevation is located on the coal seam roof, and the elevation difference between the two points is H1=896.79-893.92=2.87m;

[0021] The inclination angle of borehole c1 is θ = arctg(2.87 / 90) = 1°49′. The center hole c4 controls the base plate. The elevation difference between the two points is H1 = 896.79 - 890.42 = 6.37m. The inclination angle of borehole c4 is θ = arctg(6.37 / 90) = 4°03′.

[0022] To further optimize this technical solution, in step S5, the bottom elevation of the final borehole c2 is 892.1m, the elevation in the coal seam is 893.84m, and the borehole inclination angle is θ=arctg(2.99 / 92.77)=1°50′. Similarly, the bottom elevation of the final borehole c3 is 892.4m, the elevation in the coal seam is 894.1m, and the borehole inclination angle is θ=arctg(6.37 / 92.77)=1°39′.

[0023] Therefore, the parameters for drilling holes c1, c2, c3, and c4 are calculated as follows:

[0024] The drilling parameters for C1 are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°49′.

[0025] The drilling parameters for C2 are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°50′.

[0026] The drilling parameters for C3 are: L = 92.77m, drilling azimuth angle 75°58′, and drilling inclination angle -1°39′.

[0027] The drilling parameters for C4 are: L = 92.77m, drilling azimuth angle = 104°02′, and drilling inclination angle = -4°03′.

[0028] To further optimize this technical solution, the design of the drilling center hole in step S7 should theoretically be controlled at the top and bottom plate positions of the coal seam based on the final hole position. The inclination angle of the borehole is calculated based on the elevation of the machine center axis and the elevation of the final hole position. For example, if the center drill d1 controls the top plate, the elevation difference between the two points is its inclination angle: arctg(3.19 / 90) = 2°02′. The inclination angle of the bottom plate control hole drill d4 is arctg(6.69 / 90) = 4°15′.

[0029] To further optimize this technical solution, in step S8, the drilling parameters at drilling site B are obtained based on the drilling parameters of d2 and d3 as follows:

[0030] The drilling parameters for d1 are L = 90m, azimuth angle 90°, and inclination angle -2°02′.

[0031] The drilling parameters for d2 are L = 90m, azimuth angle 90°, and inclination angle -2°28′.

[0032] The drilling parameters for d3 are L = 92.77m, azimuth angle 75°58′, and inclination angle -2°10′.

[0033] The drilling parameters for d4 are L = 92.77m, azimuth angle of drilling is 104°02′, and inclination angle of drilling is -4°15′.

[0034] To further optimize this technical solution, based on the normal advance drilling design, additional drilling is carried out in the direction of the borehole anomaly. According to the drilling rig opening position, the location of the drilling anomaly, and the lithological changes of the coal and rock strata, the abnormal strata and the elevation of the top and bottom plates of the coal (rock) strata are inferred, and the dip angle of the additional boreholes is designed. Based on the dip angle of the abnormal boreholes, additional exploration is carried out in the vertical direction in increments of ±2° to ±5°. The drilling depth is based on the standard of clearly exploring the top and bottom plates of the coal seam in the anomaly area ahead, and generally two additional boreholes are added.

[0035] To further optimize this technical solution, the abnormal boreholes of the central hole and the side hole are drilled in sequence to increase the density of drilling. At each azimuth, three boreholes are used to control the top and bottom of the coal and rock strata ahead. Based on the dip angle of each borehole and the lithology of the continuously detected coal and rock strata, the position and elevation of the top and bottom of the coal and rock strata are calculated. The elevations of the top and bottom of the coal seam detected by the boreholes are determined. The top and bottom elevations of the coal seam detected by the boreholes are connected and extended, which is the inferred coal seam ahead.

[0036] Beneficial effects

[0037] Compared with the prior art, the present invention provides a drilling method for constructing a tunneling face, which has the following beneficial effects:

[0038] 1. The drilling method for the tunneling face involves, before commencing tunneling, utilizing existing geological work results in the mining area, including geological exploration reports, geophysical reports, drawings, and reports, to compile a geological description of the tunneling face, draw a predicted profile of the tunneling face, and, based on the characteristics of the detected anomalous geological bodies, understand the occurrence and changing trends of the coal and rock strata ahead of the tunneling face. This allows for accurate determination of the construction strata, reasonable design of the tunneling slope, minimizing the amount of work involved in tunneling through the structural bodies, reducing resource loss, improving the recovery rate, and accurately identifying the morphology, scale, spatial structure, and occurrence of the structures in order to take timely and effective pre-emptive remediation measures.

[0039] 2. This drilling method for the tunneling face involves timely measurement of the roadway during the tunneling process, especially the elevation of the roof and floor in sections where the coal and rock mass undulates. The contour map of the coal seam roof and floor of the tunneling face is revised based on the undulations of the coal seam elevation of the tunneling face and adjacent tunneling faces, as well as the geological borehole conditions in the area in front of the tunneling face. The regions, locations, and extents of possible abnormal geological bodies detected and described in various geological exploration reports are filled in on the contour map of the coal seam floor of the tunneling face.

[0040] 3. The drilling method for this tunneling face involves reconnaissance of the surface corresponding to the tunneling face to identify any exposed abnormal geological structures, water bodies, etc. For exposed abnormal geological structures such as faults, collapse columns, and folds, their spatial location, scale, size, and extent should be measured. Their location should be inferred based on the coal seam depth and filled in on the contour map of the tunneling face floor. Abnormal geological bodies outside the normal water exploration design borehole length of the tunneling face will not be drilled in additional densities, and construction will be carried out according to the normal water exploration and drainage design.

[0041] 4. The drilling method for this tunneling face involves assigning a technician with knowledge of mine geology and stratigraphic theory, as well as lithological analysis skills during drilling, to provide on-site guidance. This technician is capable of accurately identifying strata and analyzing the lithology encountered during drilling, with particular emphasis on collecting and recording original geological data. After drilling, the actual borehole trajectory is measured using a borehole trajectory instrument and a sighting instrument to correct parameters such as borehole azimuth, dip angle, and depth. The coal and rock strata and lithology revealed by the borehole are compared and analyzed, and relevant maps are drawn. After drilling, comparisons and analyses are conducted to determine the extent, location, scale, and occurrence of anomalies ahead of the tunneling face. A qualitative analysis of the structure is performed, and reliable structural safety measures are developed. Attached Figure Description

[0042] Figure 1 This is a flowchart of a drilling method for constructing a tunneling face proposed in this invention;

[0043] Figure 2 This is a drilling profile diagram of a drilling method for constructing a tunneling face proposed in this invention.

[0044] Figure 3 This is a drilling plan view of a drilling method for constructing a tunneling face proposed in this invention. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Example:

[0047] Please refer to Figure 1-3 As shown, this invention discloses a drilling method for constructing a tunneling face, comprising the following steps:

[0048] In normal areas, drilling operations are carried out in step S1. Each drilling operation involves 4 boreholes: 2 central boreholes and 2 side boreholes on the left and right sides. The central boreholes are 90 meters long, and the side boreholes are 92.8 meters deep. The central boreholes are used to control the top and bottom of the coal seam, respectively. The side boreholes are located in the coal seam, and the end of the side boreholes is 20 meters away from the side of the tunnel. In step S1, if there are no abnormalities in the geophysical drilling, a safety distance of 30 meters is designed to be left in front, and a safety distance of 20 meters is left on both sides of the tunnel. Each drilling operation is 90 meters long, and after tunneling 60 meters, the next drilling operation is carried out.

[0049] S2. Based on the elevations of the top and bottom of the coal seam in the excavated roadway and the elevations of the top and bottom of the coal seam at the drilling location, and the distance between the two points, the slope of the top and bottom of the coal seam in the excavated roadway is calculated. In step S2, the elevation of point A at a certain distance from the drilling location is 903.05m, the elevation of point B at the drilling location is 898.79m, the elevation difference between points A and B is 4.26m, and the distance is 73.78m. The slope between A and B can be calculated as: θ=arctg(4.26 / 73.78)=3°18′;

[0050] S3. Based on the elevation and slope of the top and bottom plates at the drilling location, infer the elevation of the top plate of the coal seam within the drilling range ahead, and draw the predicted coal seam profile.

[0051] S4. Drilling design: Drilling position B is at the height of the drilling rig. The height of the drilling rig's central axis from the top plate is 2m. The elevation of the drilling rig's central axis is 896.79m. The drilling depth is 90m. Based on the drilling depth and slope, the elevation of the coal seam's top plate at the final drilling position is calculated to be 893.92m, and the elevation of the bottom plate is 890.42m. In step S4, the drilling center hole design should theoretically be controlled at the top and bottom plate positions of the coal seam based on the final hole position. The drilling inclination angle is calculated based on the elevation of the drilling rig's central axis and the elevation of the final hole position.

[0052] For example, if the central borehole C1 controls the roof, its final borehole elevation is located on the coal seam roof, and the elevation difference between the two points is H1=896.79-893.92=2.87m;

[0053] The inclination angle of borehole c1 is θ = arctg(2.87 / 90) = 1°49′. The center hole c4 controls the base plate. The elevation difference between the two points is H1 = 896.79 - 890.42 = 6.37m. The inclination angle of borehole c4 is θ = arctg(6.37 / 90) = 4°03′.

[0054] S5. Regarding the design of the sidewall boreholes, to ensure the final borehole position meets specifications, the final borehole position is 20m from the two roadway sides, and its projection length on the roadway centerline is 90m. The borehole length is... The angle between the borehole and the center hole is arctg(22.5 / 90) = 14°02′. Based on the distance between the two side holes and the angle between the center hole, the positions of the final holes c2 and c3 of the two side holes can be uniquely determined. According to the modified coal seam floor contour map, the elevation of the top and bottom plates of the coal seam is obtained by interpolation. In step S5, the floor elevation of the final hole c2 is 892.1m, the elevation in the coal seam is 893.84m, and the inclination angle of the borehole is θ = arctg(2.99 / 92.77) = 1°50′. The floor elevation of the final hole c3 is 892.4m, the elevation in the coal seam is 894.1m, and the inclination angle of the borehole is θ = arctg(6.37 / 92.77) = 1°39′.

[0055] Therefore, the parameters for drilling holes c1, c2, c3, and c4 are calculated as follows:

[0056] The drilling parameters for C1 are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°49′.

[0057] The drilling parameters for C2 are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°50′.

[0058] The drilling parameters for C3 are: L = 92.77m, drilling azimuth angle 75°58′, and drilling inclination angle -1°39′.

[0059] The drilling parameters for C4 are: L = 92.77m, drilling azimuth angle = 104°02′, and drilling inclination angle = -4°03′.

[0060] S6. The Geodetic Surveying Department will calibrate the parameters of the four boreholes on-site. During drilling, a geological personnel will make original records of all drilling activities. Drilling will proceed in sequence from the calibrated central boreholes C1 and C4, to the left side borehole C2 and the right side borehole C3.

[0061] A drilling method for constructing a tunneling face, which may also include the following steps:

[0062] Step S7 of drilling in the abnormal area: The roof elevation at drilling location C is 896.82m, and the slope of the excavated roadway at drilling location C is 3°18′. Based on the length and slope, it can be preliminarily inferred that the final coal seam elevation at the borehole is 891.63m, the floor elevation is 888.13m, the height of the drilling rig's central axis from the roof is 2m, and the elevation at the drilling rig's central axis is 894.82m. The design of the drilling center hole in step S7 should theoretically be controlled at the top and bottom of the coal seam at the final hole position. The inclination angle of the borehole is calculated based on the elevation of the drilling rig's central axis and the elevation of the final hole position. For example, if the central drill d1 controls the roof, the elevation difference between the two points is its inclination angle: arctg(3.19 / 90) = 2°02′. The inclination angle of the bottom control hole d4 is arctg(6.69 / 90) = 4°15′.

[0063] The inclination angles of S8 and the left and right side boreholes are determined based on the top and bottom plate elevations of the final borehole location. The elevations of the coal seam's top and bottom plates are obtained using interpolation. The bottom plate elevation of the final borehole (d2) is 889.1m, and the expected borehole elevation in the coal seam is 890.8m. The borehole inclination angle is θ = arctg(4.02 / 92.77) = 2°28′.

[0064] The bottom elevation of borehole d3 is 889.6m, and the expected borehole elevation in the coal seam is 891.3m. The borehole inclination angle is θ = arctg(3.52 / 92.77) = 2°10′.

[0065] In step S8, the drilling parameters at drilling site B are obtained based on the drilling parameters of d2 and d3 as follows:

[0066] The drilling parameters for d1 are L = 90m, azimuth angle 90°, and inclination angle -2°02′.

[0067] The drilling parameters for d2 are L = 90m, azimuth angle 90°, and inclination angle -2°28′.

[0068] The drilling parameters for d3 are L = 92.77m, azimuth angle 75°58′, and inclination angle -2°10′.

[0069] The drilling parameters for d4 are L = 92.77m, drilling azimuth angle 104°02′, and drilling inclination angle -4°15′.

[0070] S9. According to the drilling design, the geological surveying technicians sequentially calibrate the borehole parameters and conduct drilling. When drilling reaches 34.5m, the drilling stratum changes. Based on the drilling speed and the size of the rock cuttings in the backwater, the stratum of the borehole can be preliminarily determined. Continue drilling forward to the designed position, collect and organize the original data, and, based on the normal advanced drilling design, conduct additional drilling in the direction of the borehole anomaly. Based on the drilling rig's opening position, the location of the drilling anomaly, and the changes in the lithology of the coal and rock strata, infer the abnormal stratum and the elevation of the top and bottom plates of the coal (rock) strata, and design supplementary boreholes. Based on the dip angle of the abnormal borehole, additional exploration is carried out in the vertical direction at increments of ±2° to ±5°. The drilling depth is based on clarifying the top and bottom plates of the coal seam in the abnormal area ahead. Generally, two additional boreholes are added. The abnormal boreholes of the central hole and the side hole are then drilled in a denser manner to supplement the exploration. At each azimuth, three boreholes are ensured to control the top and bottom plates of the coal seam ahead. Based on the dip angle of each borehole and the lithology of the continuously detected coal seam, the position and elevation of the top and bottom plates of the coal seam are calculated. The elevations of the top and bottom plates of the coal seam detected by the borehole are determined. The top and bottom plates of the coal seam detected by the borehole are connected and extended, which is the inferred coal seam ahead.

[0071] Working principle: When an abnormal geological structure is predicted to be within the water exploration and release design, advanced geophysical exploration is carried out before water exploration and release, within the allowable drilling distance required for water exploration and release. The spatial location, scale, size, and range of the abnormal geological body are determined by using advanced transient electrical resistivity tomography and direct current electrical resistivity tomography. The two geophysical exploration methods are cross-referenced and comprehensively analyzed. Based on the water exploration and release drilling design, the range of the geophysical anomaly area is further densified to accurately detect the anomaly area.

[0072] The location of the coal (rock) seam being probed and the location of the coal seam at the drilling anomaly during actual tunneling are the locations of the structures. By extending this to infer the location of the top and bottom plates of the coal seam during actual tunneling, borehole plan and profile diagrams are drawn. On the plan diagram, the direction of the anomaly location of the central borehole or the two side boreholes is the strike of the fault. Based on the elevation of the coal seam, the direction from the higher elevation to the lower elevation indicates the dip of the fault. On the profile diagram, the fault displacement is determined based on the drilling results.

[0073] When and after a geological structure is exposed, the geological survey department assigns specialists to conduct on-site measurements underground, collect structural attitude elements, draw structural sketches, and establish geological cards. Based on the angle between the structure and the roadway, horizontal boreholes are drilled perpendicularly to the structure at a certain distance to further verify the structural attitude elements and the direction of structural extension. Through comprehensive analysis and research, the structure is mapped to provide reliable geological data for the fully mechanized mining face after the formation of the tunneling face.

[0074] By comparing the anomaly areas obtained from the exploration results of the two methods, the consistency and overlap of the anomalies were found, thereby determining the accuracy of the geophysical exploration results. By combining this with geological data such as roadway exposure and precise external exploration, the internal structural development of the working face was accurately identified and qualitatively interpreted. Exploration using multiple underground geophysical exploration methods can effectively improve the accuracy of underground geophysical exploration in the geological structure exploration within the coal mining face, enabling more precise determination of the development morphology and location of geological structures, their extent, rock mass, and whether they are water-conducting. Simultaneous exploration, comprehensive processing and analysis, design revision to guide construction, timely collection of first-hand original data from the field, and timely revision and drawing of structural plan, cross-sectional, and profile diagrams are all conducted.

[0075] The beneficial effects of this invention are as follows: This method for drilling the structure of a tunneling face utilizes existing geological work results in the mining area, including geological exploration reports, geophysical reports, drawings, and reports, to compile a geological description of the tunneling face before construction begins. It also involves drawing a predicted profile of the tunneling face, understanding the characteristics of abnormal geological bodies, grasping the occurrence and changing trends of coal and rock strata ahead of the tunneling face, accurately determining the construction strata, rationally designing the tunneling slope, minimizing the amount of work involved in tunneling through structural bodies, reducing resource loss, and improving recovery efficiency. Accurately determine the morphology, scale, spatial structure, and occurrence of geological structures to enable timely and effective proactive remediation measures. During the tunneling process, timely measurements of the roadway are conducted, especially the roof and floor elevations in areas with varying coal and rock mass undulations. The contour maps of the coal seam roof and floor at the tunneling face are revised based on the undulations of the coal seam elevation at the tunneling face and adjacent faces, as well as the geological borehole conditions in the area ahead of the tunneling face. The regions, locations, and extents of possible anomalous geological bodies detected and described in various geological exploration reports are then mapped and incorporated into the tunneling process. On the contour map of the coal seam floor, conduct a reconnaissance of the surface corresponding to the tunneling face to identify any exposed abnormal geological structures, water bodies, etc. For exposed abnormal geological structures such as faults, collapse columns, and folds, measure their spatial location, scale, size, and extent, infer their location based on the coal seam depth, and record this information on the contour map of the tunneling face floor. For abnormal geological bodies beyond the normal water exploration design borehole length at the tunneling face, no additional drilling will be conducted; construction will proceed according to the normal water exploration and drainage design. During drilling operations, assign a person with knowledge of mine geology and related stratigraphic theories, as well as lithology knowledge relevant to drilling. The analysis involves technical personnel who can accurately determine the stratigraphic position and provide on-site guidance. This includes analyzing the lithology encountered during drilling, particularly strengthening the collection and recording of original geological data. After drilling is completed, the actual borehole trajectory is measured using a borehole trajectory instrument and a sighting instrument to correct parameters such as borehole azimuth, dip angle, and depth. The coal and rock strata and lithology revealed by the borehole are compared and analyzed, and relevant maps are drawn. After drilling is completed, comparisons and analyses are conducted to determine the extent, location, scale, and occurrence of anomalies ahead of the tunneling face. Qualitative analysis of the structure is performed, and reliable structural safety measures are formulated.

[0076] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0077] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A drilling method for constructing a tunneling face, characterized in that, Includes the following steps: In normal areas, drilling operations are carried out in the following steps: S1. Each drilling operation involves 4 boreholes, including 2 central boreholes (C1 and C4) and 2 side boreholes (C2 and C3). The central boreholes are 90 meters long, and the side boreholes are 92.8 meters deep. The central boreholes control the top and bottom of the coal seam, respectively. The side boreholes are located in the coal seam, and the end of the side boreholes is 20 meters away from the side of the tunnel. S2. Based on the elevations of the top and bottom of the coal seam in the excavated roadway and the elevations of the top and bottom of the coal seam at the drilling location, and the distance between the two points, calculate the slope of the top and bottom of the coal seam in the excavated roadway. S3. Based on the elevation and slope of the top and bottom plates at the drilling location, infer the elevation of the top plate of the coal seam within the drilling range ahead, and draw the predicted coal seam profile. S4. Conduct drilling design. The drilling location is B. The height of the drilling rig is 2m above the center axis of the drilling rig. The elevation of the center axis of the drilling rig is 896.79m. The drilling depth is 90m. Based on the drilling depth and slope, the elevation of the top plate of the coal seam at the final drilling location is 893.92m and the elevation of the bottom plate is 890.42m. S5. Regarding the design of the sidewall boreholes, to ensure the final borehole position meets specifications, the final borehole position is 20m from the two roadway sides, and its projection length on the roadway centerline is 90m. The borehole length is... The angle between the hole and the center hole is: arCtg(22.5 / 90) = 14°02′. Based on the distance between the two side holes and the angle between the hole and the center hole, the positions of the final holes C2 and C3 of the two side holes can be uniquely determined. Based on the modified coal seam floor contour map, the elevation of the coal seam top and bottom plates is obtained by interpolation. In step S5, the bottom elevation of the C2 final borehole is 892.1m, the elevation within the coal seam is 893.84m, and the borehole inclination angle is θ = arCtg(2.99 / 92.77) = 1°50′. Similarly, the bottom elevation of the C3 final borehole is 892.4m, the elevation within the coal seam is 894.1m, and the borehole inclination angle is θ = arCtg(6.37 / 92.77) = 1°39′. Therefore, the parameters for drilling holes C1, C2, C3, and C4 are calculated as follows: The drilling parameters for C1 are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°49′. The C2 drilling parameters are: L = 90m, drilling azimuth angle = 90°, drilling inclination angle = -1°50′. The C3 borehole parameters are: L = 92.77m, borehole azimuth angle 75°58′, borehole inclination angle -1°39′. The C4 drilling parameters are: L = 92.77m, drilling azimuth angle = 104°02′, drilling inclination angle = -4°03′; S6. The Geodetic Surveying Department will calibrate the parameters of the four boreholes on-site. During drilling, a geological personnel will make original records of all drilling activities. Drilling will proceed in sequence from the calibrated central boreholes C1 and C4, to the left side borehole C2 and the right side borehole C3.

2. The drilling method for constructing a tunneling face according to claim 1, characterized in that, It may also include the following steps: The drilling steps in the abnormal area are as follows: S7. The roof elevation at drilling location C is 896.82m. The slope of the excavated roadway at drilling location C is 3°18′. Based on the length and slope, it can be preliminarily inferred that the final coal seam elevation at the borehole is 891.63m, the floor elevation is 888.13m, the height between the central axis of the drilling rig and the roof is 2m, and the elevation at the central axis of the drilling rig is 894.82m. The inclination angles of S8 and the left and right side boreholes are determined based on the top and bottom plate elevations of the final borehole location. The elevations of the top and bottom plates of the coal seam are obtained by interpolation. The bottom plate elevation of the final borehole d2 is 889.1m, and the expected borehole elevation in the coal seam is 890.8m. The borehole inclination angle is θ = arCtg(4.02 / 92.77) = 2°28′. The bottom elevation of the d3 final borehole is 889.6m, the expected borehole elevation in the coal seam is 891.3m, and the borehole inclination angle is θ=arCtg(3.52 / 92.77)=2°10′; S9. According to the drilling design, the geological surveying technicians will mark the opening parameters in sequence and carry out drilling. When drilling reaches 34.5m, the drilling stratum changes. Based on the drilling speed on site and the size of the rock cuttings in the backwater, the stratum of the borehole can be preliminarily determined. Continue drilling forward to the design position and collect and organize the original data.

3. The drilling method for constructing a tunneling face according to claim 1, characterized in that, In step S1, if there are no abnormalities in the geophysical drilling, a safety distance of 30 meters is designed to be left in front and a safety distance of 20 meters is left on both sides of the tunnel. Each drilling operation is 90 meters long and 60 meters is excavated before the next drilling operation is carried out.

4. The drilling method for constructing a tunneling face according to claim 1, characterized in that, In step S2, the elevation of point A at a certain distance from the drilling location is 903.05m, and the elevation of point B at the drilling location is 898.79m. The elevation difference between points A and B is 4.26m, and the distance is 73.78m. The slope between A and B can be calculated as: θ=arCtg(4.26 / 73.78)=3°18′.

5. The drilling method for constructing a tunneling face according to claim 1, characterized in that, In step S4, the design of the drilling center hole should theoretically be controlled at the top and bottom of the coal seam based on the final hole position, and the inclination angle of the borehole should be calculated based on the elevation of the machine center axis and the elevation of the final hole position. For example, the central borehole C1 controls the roof, and its final borehole elevation is located on the coal seam roof. The elevation difference between the two points is H1=896.79-893.92=2.87m. The inclination angle of borehole C1 is θ = arCtg(2.87 / 90) = 1°49′. The center hole C4 controls the base plate. The elevation difference between the two points is H1 = 896.79 - 890.42 = 6.37m. The inclination angle of borehole C4 is θ = arCtg(6.37 / 90) = 4°03′.

6. The drilling method for constructing a tunneling face according to claim 2, characterized in that, Theoretically, the design of the drilling center hole in step S7 should be controlled at the top and bottom plate of the coal seam based on the final hole position. The inclination angle of the borehole is calculated based on the elevation of the machine center axis and the elevation of the final hole position. For example, the inclination angle of the center drill d1 controlling the top plate is arCtg(3.19 / 90) = 2°02′, and the inclination angle of the bottom plate control hole drill d4 is arCtg(6.69 / 90) = 4°15′.

7. The drilling method for constructing a tunneling face according to claim 2, characterized in that, In step S8, the drilling parameters at drilling site B are obtained based on the drilling parameters of d2 and d3 as follows: The drilling parameters for d1 are L = 90m, azimuth angle 90°, and inclination angle -2°02′. The drilling parameters for d2 are: L = 90m, azimuth angle of 90°, and inclination angle of -2°28′. The drilling parameters for d3 are L = 92.77m, azimuth angle 75°58′, and inclination angle -2°10′. The drilling parameters for d4 are L = 92.77m, azimuth angle of drilling is 104°02′, and inclination angle of drilling is -4°15′.

8. The drilling method for constructing a tunneling face according to claim 2, characterized in that, Based on the normal advance drilling design, additional drilling is carried out in the direction of the borehole anomaly. According to the drilling rig opening position, the location of the drilling anomaly, and the lithological changes of the coal and rock strata, the abnormal strata and the elevation of the top and bottom plates of the coal (rock) strata are inferred, and the dip angle of the additional boreholes is designed. Based on the dip angle of the abnormal boreholes, additional exploration is carried out in the vertical direction in increments of ±2° to ±5°. The drilling depth is based on the standard of clearly exploring the top and bottom plates of the coal seam in the anomaly area ahead. Generally, two additional boreholes are added.

9. The drilling method for constructing a tunneling face according to claim 8, characterized in that, The abnormal boreholes of the central hole and the side hole are drilled in sequence to increase the density of drilling. At each azimuth, three boreholes are used to control the top and bottom of the coal and rock strata ahead. The position and elevation of the top and bottom of the coal and rock strata are calculated based on the dip angle of each borehole and the lithology of the continuously detected coal and rock strata. The elevation of the top and bottom of the coal seam detected by the borehole is determined. The elevation of the top and bottom of the coal seam detected by the borehole is connected and extended to form the inferred coal seam ahead.

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