Coal uncovering method for gently inclined coal seams

Abstract

The application discloses a method for uncovering a gently inclined coal seam, and relates to the field of tunnel engineering.The method comprises the following steps: preliminarily judging the position and the inclination angle of a coal seam face of the gently inclined coal seam, and determining the position and the inclination angle of a first working face and a second working face; the first working face, the second working face and the coal seam face are arranged in parallel, and the first working face, the second working face and the coal seam face are arranged in sequence and at intervals in a direction close to the coal seam face; the stratum is excavated to the first working face by using a bench method; the stratum is excavated to the second working face from the first working face by using a three-bench method; a pilot pit is formed by excavating in the direction close to the coal seam face at the second working face; and the gently inclined coal seam is uncovered by blasting in the pilot pit, and the gas in the gently inclined coal seam is discharged. The method for uncovering the gently inclined coal seam can uncover the gently inclined coal seam completely at one time, and the steps are simple and the time consumption is short.

Description

Technical Field

[0001] This invention relates to the field of tunnel engineering technology, and in particular to a method for exposing coal seams in gently inclined coal seams. Background Technology

[0002] With the comprehensive advancement of transportation infrastructure, especially high-speed railways that traverse mountains and valleys with straight, large-radius curves, the lines inevitably cross numerous coal-bearing strata. When tunnels pass through coal seams, the risk of coal and gas outbursts is significant. The powerful impact of coal and gas outbursts can not only damage the tunnel structure and ventilation system but may also lead to gas explosions, suffocation, or even explosions, seriously threatening the safe construction of the tunnel. Therefore, before tunnel construction, it is necessary to open the coal seam to release and expel the gas within.

[0003] Currently, tunnel construction often encounters gently inclined coal seams with a certain angle of inclination in the strata. Due to the angle of inclination, existing construction methods cannot completely uncover the gently inclined coal seam in one go. Usually, the gently inclined coal seam is divided into multiple parts, and then the multiple parts of the gently inclined coal seam are uncovered one by one. The process is cumbersome and time-consuming. Summary of the Invention

[0004] The main objective of this invention is to provide a method for uncovering gently inclined coal seams, which aims to solve the technical problem that existing construction methods cannot completely uncover gently inclined coal seams in one go, and the steps are cumbersome and time-consuming.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a method for exposing coal in a gently inclined coal seam, the method comprising:

[0007] The position and inclination angle of the coal surface of the gently inclined coal seam are initially determined, and the position and inclination angle of the first working face and the second working face are determined; wherein, the first working face, the second working face and the coal surface are arranged parallel to each other, and the first working face, the second working face and the coal surface are arranged alternately in the direction closer to the coal surface;

[0008] The strata were excavated to the first working face using the step method;

[0009] The strata are excavated from the first working face to the second working face using the three-step method;

[0010] A pilot tunnel is formed by excavating in the second working face in a direction close to the coal seam;

[0011] Blasting is carried out in the pilot tunnel to expose the gently dipping coal seam and remove the gas from the gently dipping coal seam.

[0012] Optionally, the step of excavating the strata to the first working face using the step method includes:

[0013] The strata are excavated to the first working face by forming two steps using the step method; wherein the two steps are the upper step and the lower step.

[0014] The step of excavating the strata from the first working face to the second working face using the three-step method includes:

[0015] The upper step is divided into a first step and a second step from the first working face. The first step, the second step, and the lower step form three steps. The stratum is excavated to the second working face using the three-step method.

[0016] Optionally, the step of dividing the upper bench from the first working face into a first bench and a second bench, the first bench, the second bench, and the lower bench forming three benches, and excavating the stratum to the second working face using the three-bench method includes:

[0017] The upper step is divided into a first step and a second step; wherein the first step, the second step, and the lower step form three steps;

[0018] The lengths of the first step and the second step are determined based on the inclination angle of the gently sloping coal seam.

[0019] The upper step is excavated to form the first step and the second step according to the determined lengths of the first step and the second step;

[0020] The strata are excavated from the first working face to the second working face using the three-step method.

[0021] Optionally, the step of excavating a pilot tunnel in the second working face toward the coal seam includes:

[0022] At the junction of the first step and the second step of the second working face, the pilot tunnel is excavated horizontally towards the coal seam to form the pilot tunnel.

[0023] Optionally, the step of excavating the strata to the first working face using the step method includes:

[0024] The strata were excavated to the first inspection surface using the step method;

[0025] Advanced geological prediction is performed on the strata in the first detection face to accurately obtain the position and inclination angle of the coal seam, and to correct the position and inclination angle of the first working face and the second working face.

[0026] The strata are excavated from the first detection surface to the first working surface using a step method.

[0027] Optionally, the step of performing advanced geological prediction on the stratum at the first detection face to accurately obtain the position and dip angle of the coal seam, and correcting the position and dip angle of the first working face and the second working face includes:

[0028] Core sampling is performed on the stratum from the first detection surface in the direction of closer to the gently dipping coal seam to obtain the geological body to be tested;

[0029] The geological body to be tested is tested, and the strata are used for advanced geological prediction to accurately obtain the position and inclination angle of the coal seam, and to correct the position and inclination angle of the first working face and the second working face.

[0030] Optionally, the step of excavating the stratum from the first detection surface to the first working surface using the step method includes:

[0031] The strata are excavated from the first detection surface to the second detection surface using a step-by-step method.

[0032] The second detection method performs outburst risk prediction on the gently dipping coal seam in the stratum and determines whether the detection results meet the design and specification requirements.

[0033] When the results of the hazard detection meet the design and specification requirements, the strata are excavated from the second detection face to the first working face using the step method, based on the inclination angle of the coal seam obtained from the advanced geological forecast.

[0034] Optionally, the step of predicting the outburst risk of the gently dipping coal seam in the stratum at the second detection surface and determining whether the detection results meet the design and specification requirements further includes:

[0035] When the results of the hazard detection do not meet the design and specification requirements, the gently inclined coal seam shall be treated for outburst prevention until the design and specification requirements are met.

[0036] Optionally, the first detection surface, the second detection surface, the first working surface, and the second working surface are arranged parallel to each other, and the first detection surface, the second detection surface, the first working surface, and the second working surface are arranged sequentially in the direction of approaching the coal surface. The distance between the first detection surface and the coal surface is 20m, the distance between the second detection surface and the coal surface is 10m, the distance between the first working surface and the coal surface is 5m, and the distance between the second working surface and the coal surface is 2m.

[0037] Optionally, before the step of excavating a pilot tunnel in the direction close to the coal seam from the second working face, the method further includes:

[0038] A support structure is constructed on the second working face.

[0039] The above-described one or more technical solutions provided by this invention can have the following advantages or at least achieve the following technical effects:

[0040] This invention proposes a method for excavating gently dipping coal seams. First, the location and inclination angle of the coal seam are initially determined. Then, based on these determined locations and inclination angles, the locations and inclination angles of the first and second working faces are determined. The strata are first excavated to the first working face parallel to the coal seam using a bench method. Then, a three-bench method is used to excavate to the second working face parallel to the coal seam. Because the second working face is closer to the coal seam, the three-bench method allows for more precise excavation to the second working face, effectively avoiding over-excavation and resulting in a thin strata that cannot meet subsequent blasting requirements. A pilot pit is formed by excavating the strata at the second working face. Explosives are buried in the pilot pit and blasted to completely open the strata surrounding the pilot pit in one go, achieving the one-time excavation of the gently dipping coal seam and releasing the gas within it. The process is simple and time-efficient. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic flowchart of the first embodiment of the coal uncovering method for gently inclined coal seams of the present invention;

[0043] Figure 2 This is a detailed flowchart of step 200 in the coal uncovering method for gently inclined coal seams of the present invention.

[0044] Figure 3 This is a detailed flowchart of step 203 in the coal uncovering method for gently inclined coal seams of the present invention.

[0045] Figure 4 This is a detailed flowchart of step 300 in the coal uncovering method for gently inclined coal seams of the present invention.

[0046] Figure 5 This is a schematic diagram of the excavation of a gently inclined coal seam as described in the present invention;

[0047] Figure 6 This is a schematic diagram of the structure of the first step, the second step, the lower step, and the guide pit involved in the present invention.

[0048] Explanation of icon numbers:

[0049]

[0050]

[0051] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0053] It should be noted that in the embodiments of the present invention, all directional indications (such as up, down, left, right, front, back, etc.) are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0054] In this invention, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element. Furthermore, the meaning of "and / or" throughout the text includes three parallel options; for example, "A and / or B" includes option A, option B, or options where both A and B are satisfied.

[0055] In this invention, unless otherwise explicitly specified and limited, the terms "connection" and "fixed" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements.

[0056] In this invention, if there are descriptions involving "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0057] In this invention, the use of suffixes such as "module," "component," "part," "unit," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" can be used interchangeably.

[0058] For those skilled in the art, the specific meanings of the above terms in this invention can be understood according to the specific circumstances. Furthermore, the technical solutions of the various embodiments can be combined with each other; however, this is based on the premise that those skilled in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0059] The inventive concept of the present invention will be further explained below with reference to some specific embodiments.

[0060] This invention proposes a method for uncovering gently inclined coal seams 10, the method comprising:

[0061] Step S100: Preliminarily determine the position and inclination angle of the coal surface of the gently inclined coal seam, and determine the position and inclination angle of the first working face and the second working face; wherein, the first working face 50, the second working face 60 and the coal surface 20 are arranged parallel to each other, and the first working face 50, the second working face 60 and the coal surface 20 are arranged alternately in the direction close to the coal surface 20.

[0062] Step S200: The strata are excavated to the first working face using the step method;

[0063] Step S300: Excavate the stratum from the first working face to the second working face using the three-step method;

[0064] Step S400: Excavate a pilot tunnel in the second working face in the direction close to the coal seam to form a pilot tunnel;

[0065] In step S500, blasting is carried out in the pilot tunnel to expose the gently inclined coal seam and remove the gas from the gently inclined coal seam.

[0066] Specifically, such as Figure 1 , Figure 5 and Figure 6 As shown, before excavating the strata, the position of the coal surface 20 and the inclination angle of the gently dipping coal seam 10 are initially determined based on the existing design data. Then, based on the determined position of the coal surface 20 and the inclination angle of the coal seam, the positions and inclination angles of the first working face 50 and the second working face 60 are determined. First, the strata are excavated to form two steps using the step method. By excavating the two steps, the strata are excavated to the first working face 50, which is parallel to the coal surface 20. Then, the strata are excavated to form three steps using the three steps. By excavating the three steps, the strata are excavated to the second working face 60, which is parallel to the coal surface 20. Since the second working face 60 is closer to the coal surface 20, the three-step method can more accurately excavate the strata to the second working face 60, which can effectively avoid over-excavation of the strata and result in a thin strata thickness that cannot meet the subsequent blasting requirements. In the second working face 60, the strata are excavated to form a pilot tunnel 90. Explosives are buried in the pilot tunnel 90 for blasting to completely blast open the strata around the pilot tunnel 90 at one time, thereby achieving the one-time opening of the gently inclined coal seam 10 and releasing the gas in the gently inclined coal seam 10. The steps are simple and the time consumption is short.

[0067] In one embodiment, step S200 includes:

[0068] Step S210: The stratum is excavated to the first working face by forming two steps using the step method; wherein the two steps are the upper step and the lower step.

[0069] Step S300 includes:

[0070] Step S310: Divide the upper step from the first working face into a first step and a second step. The first step, the second step, and the lower step form three steps. Use the three-step method to excavate the stratum to the second working face.

[0071] Specifically, such as Figure 5 and Figure 6 As shown, based on the upper step 80 and lower step 70 formed by the step method, the upper step 80 is divided into the first step 81 and the second step 82 to form three steps. Then, the strata are excavated from the first working face 50 to the second working face 60 through the three steps. The step division is reasonable and the design is ingenious, which greatly shortens the time for excavating the steps and consumes less time.

[0072] In one embodiment, step S310 includes:

[0073] Step S311: Divide the upper step into the first step and the second step; wherein the first step 81, the second step 82 and the lower step 70 form three steps;

[0074] Step S312: Determine the length of the first step and the length of the second step according to the inclination angle of the gently sloping coal seam;

[0075] Step S313: The upper step is excavated to form the first step and the second step according to the length of the first step and the length of the second step;

[0076] Step S314: Excavate the stratum from the first working face to the second working face using the three-step method.

[0077] Specifically, such as Figures 4 to 6 As shown, during the process of excavating the upper bench 80 to form two benches, the length of the first bench 81 and the length of the second bench 82 need to be determined according to the inclination angle of the coal seam 20. This ensures that the second working face 60, formed by excavating the strata using the first bench 81, the second bench 82, and the lower bench 70, is parallel to the coal seam 20. The distance between the second working face 60 and the coal seam 20 is uniform, so that when the gently inclined coal seam 10 is opened by blasting, the gently inclined coal seam 10 can be opened more uniformly.

[0078] In one embodiment, step S400 includes:

[0079] Step S410: At the junction of the first step and the second step of the second working face, the guide pit is excavated horizontally towards the coal seam to form the guide pit.

[0080] Specifically, such as Figure 5 and Figure 6As shown, after advancing the first step 81 and the second step 82 to the second working face 60, a pilot tunnel 90 is excavated at the position of the first step 81 and the second step 82. The pilot tunnel 90 is located at the junction of the first step 81 and the second step 82, and between the first step 81 and the second step 82, so that the blasting position is in a relatively central position on the second working face 60. When the gently inclined coal seam 10 is exposed by blasting, the gently inclined coal seam 10 can be exposed more evenly, and the exposure effect of the gently inclined coal seam 10 is better.

[0081] In one embodiment, step S200 includes:

[0082] Step S201: The stratum is excavated to the first detection surface using the step method;

[0083] Step S202: Perform advanced geological prediction on the first detection face to accurately obtain the position and inclination angle of the coal seam, and correct the position and inclination angle of the first working face and the second working face.

[0084] Step S203: Excavate the stratum from the first detection surface to the first working surface using the step method.

[0085] Specifically, such as Figure 2 , Figure 5 and Figure 6 Before excavating the strata to the first working face 50, the strata should first be excavated to the first inspection face 30. Advanced geological prediction should be conducted at the first inspection face 30 to more accurately obtain the position and inclination angle of the coal seam 20. Based on the more accurate position and inclination angle of the coal seam 20, the positions and inclination angles of the first working face 50 and the second working face 60 should be corrected to ensure that each working face is parallel to the coal seam 20, and the distance between the second working face 60 and the coal seam 20 is more precise. During blasting, the gently dipping coal seam 10 can be more evenly and completely exposed, resulting in a better exposure effect.

[0086] In one embodiment, step S202 includes:

[0087] Step S2021: Drill a core from the first detection surface toward the stratum towards the gently dipping coal seam to obtain the geological body to be tested;

[0088] Step S2022: Detect the geological body to be tested, perform advanced geological prediction on the strata, accurately obtain the position and inclination angle of the coal seam, and correct the position and inclination angle of the first working face and the second working face.

[0089] In one embodiment, step S203 includes;

[0090] Step S204: Excavate the stratum from the first detection surface to the second detection surface using the step method;

[0091] Step S205: On the second detection surface, predict the outburst risk of the gently dipping coal seam in the stratum, and determine whether the detection results meet the design requirements and specification requirements;

[0092] Step S206: When the detection results of the prominent hazard detection meet the design requirements and specification requirements, the stratum is excavated from the second detection face to the first working face using the step method based on the inclination angle of the coal seam obtained by advanced geological forecasting.

[0093] Specifically, such as Figure 3 , Figure 5 and Figure 6 As shown, after the stratum is excavated to the first detection face 30, it is then excavated to the second detection face 40. At the second detection face 40, the outburst risk of the gently inclined coal seam 10 in the stratum is predicted. When the outburst risk detection results meet the design requirements and specifications, the stratum can be excavated to the first working face 50. By predicting the outburst risk of the gently inclined coal seam 10, the probability of accidents can be effectively reduced, and the safety and reliability are high.

[0094] In one embodiment, step S205 further includes:

[0095] Step S2051: When the detection results of the outburst hazard detection do not meet the design requirements and specification requirements, outburst prevention treatment shall be carried out on the gently inclined coal seam until the design requirements and specification requirements are met.

[0096] In one embodiment, the first detection surface 30, the second detection surface 40, the first working surface 50, and the second working surface 60 are arranged parallel to each other, and the first detection surface 30, the second detection surface 40, the first working surface 50, and the second working surface 60 are arranged sequentially towards the coal surface 20. The distance between the first detection surface 30 and the coal surface 20 is 20m, the distance between the second detection surface 40 and the coal surface 20 is 10m, the distance between the first working surface 50 and the coal surface 20 is 5m, and the distance between the second working surface 60 and the coal surface 20 is 2m.

[0097] Specifically, such as Figure 5As shown, the strata are excavated based on the initially determined location of the coal seam 20. When the excavation reaches a position 20m vertically from the initially determined location of the coal seam 20, a first detection surface 30 is formed. Advanced geological prediction of the gently dipping coal seam 10 is performed on the first detection surface 30, allowing for earlier acquisition of the location and inclination angle of the coal seam 20. Furthermore, the distance between the first detection surface 30 and the coal seam 20 is moderate, resulting in more accurate acquisition of the location and inclination angle of the coal seam 20. After completing the advanced prediction of the gently dipping coal seam 10, the subsequent strata excavation is adjusted based on the more accurate location and inclination angle of the coal seam 20. The angle and distance of the slope allow for higher excavation accuracy. The strata are excavated to a position 10m vertically from the coal seam 20 to form a second detection face 40. Outburst hazard detection of the coal seam 20 is performed on the second detection face 40, resulting in higher prediction accuracy and greater safety and reliability. When the strata are excavated to a position 5m vertically from the coal seam 20, the construction method is changed from the step method to the three-step method. Since the distance between the first working face 50 and the coal seam 20 is relatively close, the three-step method allows for more precise excavation to a position 2m vertically from the coal seam 20, resulting in higher accuracy.

[0098] In one embodiment, before step S400, the method further includes:

[0099] Step S001: Construct a support structure on the second working face.

[0100] Specifically, the support structure can reinforce the strata of the second working face 60, preventing the soil around the pilot tunnel 90 from collapsing due to disturbance when the pilot tunnel 90 is excavated, thus improving safety and reliability.

[0101] It should be noted that the sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above embodiments are only optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made under the inventive concept of the present invention using the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are all included within the patent protection scope of the present invention.

Claims

1. A method for uncovering coal in a gently dipping coal seam, characterized in that, The method for uncovering the gently dipping coal seam includes: The position and inclination angle of the coal surface of the gently inclined coal seam are initially determined, and the position and inclination angle of the first working face and the second working face are determined; wherein, the first working face, the second working face and the coal surface are arranged parallel to each other, and the first working face, the second working face and the coal surface are arranged alternately in the direction closer to the coal surface; The strata were excavated to the first working face using the step method; The strata are excavated from the first working face to the second working face using the three-step method; A pilot tunnel is formed by excavating in the second working face in a direction close to the coal seam; Blasting is carried out in the pilot tunnel to expose the gently dipping coal seam and remove the gas from the gently dipping coal seam; The step of excavating the strata to the first working face using the step method includes: The strata were excavated to the first inspection surface using the step method; Core sampling is performed on the stratum from the first detection surface in the direction of closer to the gently dipping coal seam to obtain the geological body to be tested; The geological body to be tested is tested, and the strata are advanced geologically predicted to accurately obtain the position and dip angle of the coal seam, and to correct the position and dip angle of the first working face and the second working face. The strata are excavated from the first detection surface to the second detection surface using a step-by-step method. The second detection method performs outburst risk prediction on the gently dipping coal seam in the stratum and determines whether the detection results meet the design and specification requirements. When the results of the hazard detection meet the design and specification requirements, the strata are excavated from the second detection face to the first working face using the step method, based on the inclination angle of the coal seam obtained from the advanced geological forecast. When the results of the hazard detection do not meet the design and specification requirements, the gently inclined coal seam shall be treated for outburst prevention until the design and specification requirements are met.

2. The method for revealing coal seams in a gently dipping seam as described in claim 1, characterized in that, The step of excavating the strata to the first working face using the step method includes: The strata are excavated to the first working face by forming two steps using the step method; wherein the two steps are the upper step and the lower step. The step of excavating the strata from the first working face to the second working face using the three-step method includes: The upper step is divided into a first step and a second step from the first working face. The first step, the second step, and the lower step form three steps. The stratum is excavated to the second working face using the three-step method.

3. The method for revealing coal seams in a gently dipping seam as described in claim 2, characterized in that, The step of dividing the upper bench from the first working face into a first bench and a second bench, the first bench, the second bench, and the lower bench forming three benches, and excavating the strata to the second working face using the three-bench method includes: The upper step is divided into a first step and a second step; wherein the first step, the second step, and the lower step form three steps; The lengths of the first step and the second step are determined based on the inclination angle of the gently sloping coal seam. The upper step is excavated to form the first step and the second step according to the length of the first step and the length of the second step; The strata are excavated from the first working face to the second working face using the three-step method.

4. The method for revealing coal seams in a gently dipping seam as described in claim 2, characterized in that, The step of excavating a pilot tunnel in the second working face in a direction close to the coal seam includes: At the junction of the first step and the second step of the second working face, the pilot tunnel is excavated horizontally towards the coal seam to form the pilot tunnel.

5. The method for revealing coal seams in a gently dipping seam as described in claim 1, characterized in that, The first detection surface, the second detection surface, the first working surface, and the second working surface are arranged parallel to each other, and are arranged sequentially towards the coal seam. The distance between the first detection surface and the coal seam is 20m, the distance between the second detection surface and the coal seam is 10m, the distance between the first working surface and the coal seam is 5m, and the distance between the second working surface and the coal seam is 2m.

6. The method for uncovering coal seams in gently dipping seams as described in any one of claims 1 to 4, characterized in that, Before the step of excavating a pilot tunnel in the direction close to the coal seam from the second working face, the method further includes: A support structure is constructed on the second working face.

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