Method for preventing and treating head-on rock burst disaster of driving face and water injection bag system

Abstract

The invention discloses a method for preventing and treating a heading face head-on rock burst disaster and a water injection bag system. The method comprises the steps that S1, the number and positions of directional pressure relief drill holes, face heading parameters and water injection bag distribution parameters are determined; arranging the bags according to parameters, and injecting water into the bags; s2, the water injection bag at the outermost end is subjected to water drainage and pressure relief, the bag subjected to water drainage and pressure relief is pushed to the position of the adjacent water injection bag, and tunneling is conducted; and S3, stopping tunneling, taking back the bag which is subjected to water drainage and pressure relief, then performing water drainage and pressure relief on the next water injection bag, pushing the bag which is subjected to water drainage and pressure relief to the adjacent water injection bag, and starting the next section of tunneling until the next section of tunneling reaches the designed position. The water injection bag system comprises a plurality of bags, a water injection pipe, a one-way valve, a water outlet pipe and a ball valve, during water injection, water is unidirectionally injected into each bag through each one-way valve along the water injection pipe; during drainage, the water outlet pipe ball valve is opened, and water in the water injection bag flows out along the water outlet pipe for pressure relief.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock burst disaster prevention and coal mine safety mining, and particularly relates to a method for preventing and treating rock burst disaster at the head of a tunneling working face and a water injection bag system. BACKGROUND

[0002] In the prior art, the main rock burst disaster of coal mining occurs, and with the continuous increase of mining depth, the rock burst disaster becomes more serious. Rock burst can easily cause mass casualties and seriously threaten the safety of miners.

[0003] In order to reduce the risk of rock burst disaster, the industry has developed strict measures for rock burst prevention. In the tunneling working face with impact risk, drilling pressure relief must be carried out at the head, and the advance pressure relief distance must be maintained. For example, a method for grading and alternating pressure relief of a strong impact risk area tunneling working face (CN202210113850.7) proposes an alternating shield drilling pressure relief method at the head. Due to the timeliness of drilling pressure relief, the tunneling at the head of the tunneling working face and the drilling pressure relief are cross performed, which has great construction difficulty and complicated operation, and seriously affects the tunneling speed. It is a key problem to be solved in the current tunneling working face. SUMMARY

[0004] The purpose of the present application is to provide a method for preventing and treating rock burst disaster at the head of a tunneling working face and a water injection bag system to solve the above problems. The present application drills long distance directional pressure relief boreholes in advance; then distributes water injection bags in the long distance pressure relief boreholes, maintains the borehole structure, and prevents borehole collapse failure; then follows the procedure of water injection bag water discharge pressure relief-tunneling-extraction of pressure relief bag-water injection bag water discharge pressure relief-tunneling-extraction of pressure relief bag from outside to inside, thereby forming an effective pressure relief hole. This method solves the problem of pressure relief at the head of the tunneling working face and the problem of low cross rate of traditional tunneling at the head of the tunneling working face and drilling pressure relief, greatly improving the work efficiency.

[0005] To achieve the above purpose, the present application provides the following technical solutions:

[0006] A method for preventing and treating rock burst disaster at the head of a tunneling working face, the steps of which are:

[0007] S1, determine the number and position of long distance directional pressure relief boreholes at the head of the tunneling working face, then determine the tunneling parameters of the working face and determine the water injection bag distribution parameters according to the tunneling parameters of the working face; drill long distance directional pressure relief boreholes according to the tunneling parameters of the working face, then arrange the bags according to the water injection bag distribution parameters, and inject water to the water injection bags to reach the set water injection pressure;

[0008] S2, when the tunnel starts to be excavated, the outermost water injection bag is drained and pressure released, the drained and pressure released bag is pushed to the adjacent water injection bag with the water outlet pipe, and the excavation starts;

[0009] S3, the excavation is stopped, the drained and pressure released bag is retrieved, then the next water injection bag is drained and pressure released, the drained and pressure released bag is pushed to the adjacent water injection bag with the water outlet pipe, and the next section of excavation starts;

[0010] S4, the step S3 is repeated until the excavation reaches the designed position.

[0011] As an improvement to the above technical solution, in the step S1, the principle for determining the number of long-distance directional pressure release boreholes for the head-on construction of the excavation face is that two long-distance directional pressure release boreholes are constructed for the head-on construction of the excavation face of the roadway with weak impact danger, three long-distance directional pressure release boreholes are constructed for the head-on construction of the excavation face of the roadway with medium or above impact danger, and the position of the long-distance directional pressure release borehole for the head-on construction of the excavation face is determined according to the cross-sectional size of the head-on working face of the roadway.

[0012] As an improvement to the above technical solution, the position of the long-distance directional pressure release borehole for the head-on construction of the excavation face is determined according to the cross-sectional size of the head-on working face of the roadway, when the interval between adjacent long-distance directional pressure release boreholes is 0.8-1.2 m and there are two boreholes, the two long-distance directional pressure release boreholes are symmetrically distributed along the vertical symmetry axis of the head-on excavation face, and the distance from the floor is 0.5-1.5 m; when the interval between adjacent long-distance directional pressure release boreholes is 0.8-1.2 m and there are three boreholes, the three boreholes are arranged in a three-flower pattern, that is, one borehole is arranged on the vertical symmetry axis on the basis of the two boreholes, and is located above the two boreholes. The diameter of the directional pressure release borehole for the head-on construction of the excavation face is 120-200 mm.

[0013] As an improvement to the above technical solution, in the step S1, the method for determining the excavation face excavation parameters and the water injection bag distribution parameters is as follows:

[0014] S101, in the excavation face excavation parameters, the daily progress is L, the advance pressure release distance is S, the length of the bare hole section not supported by the water injection bag in the hole is q, and the length of a single water injection bag is w; to ensure consistency in the initial state, the length of the outermost section not supported by the water injection bag in the initial state is also S, that is, the advance pressure release distance is S;

[0015] S102, to ensure the reliability of pressure release, q≥S is always true during the entire excavation process; to ensure the consistency of theory and practice, q=S is always true during the entire excavation process;

[0016] S103, after the water injection bag is unloaded for a distance and the L distance is excavated, q=S+w-L, if w

[0017] If w>L, then q=S+w-L>S, which violates the consistency of theory and practice; this case causes the length of the bare hole section to continue to accumulate after multiple cycles, and the system state gradually deviates from the original design; and the deeper bare hole section, the hole is prone to collapse and failure due to ground pressure due to long-term lack of support, so that the pre-designed pressure relief channel cannot play a pressure relief role;

[0018] Then it can be determined that w=L, after the water injection bag is unloaded for a distance and the L distance is excavated, q=S+w-L=S; this makes the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the theoretical value of the advanced pressure relief distance is dynamically maintained, realizing the unity of safety and continuity;

[0019] S104, the water injection bag distribution parameter N=[D / L], wherein [] represents the down rounding operation, D is the total length of the long-distance directional pressure relief drill hole, and L is the length of the water injection bag.

[0020] As an improvement to the above technical solution, in steps S2 and S3, the water injection bag with water discharged is pushed to the adjacent water injection bag along with the water outlet pipe, that is, the water injection bag with water discharged is pushed to the adjacent water storage bag S along with the water outlet pipe, the advanced pressure relief distance S is a theoretical value calculated based on geomechanics parameters, and is a critical distance for ensuring excavation safety. The distance between the peak support pressure of the heading face and the coal wall is determined by the drilling method to be an advanced pressure relief distance S≧8m.

[0021] As an improvement to the above technical solution, the initial water injection pressure of the water injection bag is set to 2-3MPa.

[0022] In order to ensure the smooth implementation of the method for preventing and controlling rock burst disaster at the heading face of the excavation working face, as an improvement to the above technical solution, the application also provides a water injection bag system used in the method for preventing and controlling rock burst disaster at the heading face of the excavation working face, which comprises a plurality of water injection bags, a water injection pipe for injecting water into the water injection bags, a check valve arranged on a connecting pipeline between the water injection pipe and the water injection bag, a water outlet pipe for discharging water from the water injection bag, and a ball valve arranged on a connecting pipeline between the water injection bag and the water outlet pipe. When water injection is performed, water is injected into each water injection bag through each check valve along the water injection pipe, and becomes a water injection bag; when water discharge is performed, the ball valve of the water outlet pipe is opened, and the water in the water injection bag flows out along the water outlet pipe, thereby achieving pressure relief.

[0023] Compared with the prior art, the application has the following advantages:

[0024] 1. Long-distance controllable pressure relief is achieved. The method maintains the pressure relief borehole structure by water injection with pressure through the bag, avoiding the collapse failure problem of long-distance pressure relief borehole, while restoring the free deformation of the borehole when needed, achieving the pressure relief effect of the borehole.

[0025] 2. The driving efficiency is greatly improved. The time-consuming drilling construction link is completely front-loaded, and only the segmented drainage pressure relief, pushing and recycling of the water injection bag are needed during the driving process, avoiding the frequent intersection of driving and pressure relief in the traditional method, the construction interruption caused by the frequent retreat of the driving machine, significantly reducing the non-driving time, and greatly improving the overall driving efficiency of the roadway.

[0026] 3. The bag used in the method adopts a detachable and reusable design, achieving low cost and high efficiency. In the recycling link, the bag can be completely taken out and reused for subsequent drilling after inspection and maintenance, reducing the single use cost of the bag.

[0027] 4. The key parameter design of the water injection bag in the method is scientific and reasonable, and has strong operability. The unit length of the water injection bag is consistent with the daily footage L. This design ensures that the actual bare hole length in front of the driving completion is always dynamically equal to the theoretical value of the advanced pressure relief distance, perfectly realizing the unity of safety and continuity. The length of the water outlet pipe and the distance from the one-way valve on the water injection pipeline to the bottom of the bag are consistent with the theoretical calculation of the advanced pressure relief distance S. This design ensures that the drainage ball valve and the water injection one-way valve interface can be accurately exposed in the hole operation range after each cycle of roadway driving, making the pressure relief operation and component recycling process clear and accurate in position, greatly improving the operability of the site operation and the reliability of the process connection.

[0028] 5. The initial water injection pressure of the water injection bag in the method is set to 2-3 MPa, which significantly reduces the difficulty and cost of system implementation while ensuring effective support of the borehole. This pressure range fully utilizes the incompressibility of fluid, enabling the water injection bag to adapt to the deformation of surrounding rock and provide strong passive support reaction, achieving technical reliability and economy. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, a brief introduction will be given below to the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0030] Figure 1 It is a schematic diagram of the overall structure of the pressure relief borehole profile of the present application.

[0031] Figure 2 To Figure 1 decomposition Figure 1 ;

[0032] Figure 3 To Figure 1 decomposition Figure 2 .

[0033] 1 - water injection pipe; 2 - ball valve; 3 - water outlet pipe; 4 - water injection bag; 5 - one-way valve; 15 - heading; 16 - pressure relief borehole. DETAILED DESCRIPTION

[0034] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0035] Referring to Figures 1-3 , the present application provides a method for preventing and treating heading rock burst disaster at a tunneling working face, and the theoretical steps are:

[0036] Step one: determine the arrangement parameters of long-distance directional pressure relief borehole:

[0037] Determine the number of long-distance directional pressure relief boreholes 16 at the heading 15 of the tunneling working face according to the overall evaluation result of the impact risk of the to-be-excavated roadway: for the roadway with weak impact risk, construct 2 long-distance directional pressure relief boreholes at the heading 15 of the tunneling working face; for the roadway with medium or above impact risk, construct 3 long-distance directional pressure relief boreholes at the heading 15 of the tunneling working face. The pressure relief borehole 16 is located in the heading working face of the roadway, and the specific position is determined according to the cross-section size. The long-distance directional pressure relief borehole 16 is constructed along the designed position of the roadway heading 15, and the length of a single long-distance directional pressure relief borehole 16 is the length of the roadway plus K, K is not less than 30 m. The remaining parameters are determined according to the design size of the roadway.

[0038] Step two: determine the tunneling parameters of the working face:

[0039] According to the actual conditions of the mine, determine the daily progress L. Determine the distance from the coal wall to the peak support pressure of the heading (the depth of the plastic zone of the heading) by the drilling method, that is, the advanced pressure relief distance S, which is generally greater than 8 m.

[0040] Step three: determine the parameters of the distributed water injection bag:

[0041] The length of the distributed water injection bag is consistent with the daily progress, which is L.

[0042] The scientificity and necessity of the parameter design are demonstrated as follows:

[0043] Assume the single segment bag length is w.

[0044] The advanced pressure relief distance S is a theoretical value calculated based on geomechanics parameters, which is a critical distance to ensure the safety of excavation. In actual working conditions, after excavation, the length q of the bare hole segment in the hole that is not supported by the bag is the actual effective advanced pressure relief zone length. To ensure the reliability of pressure relief, q=S throughout the entire excavation process. In order to make the theory consistent with the actual situation, q=S throughout the entire excavation process.

[0045] First, the initial state consistency should be ensured. The length of the outermost segment without bag support in the initial state is exactly S, which fully meets the requirement of the theoretical advanced pressure relief distance and provides the correct initial safety condition and consistent condition for the system.

[0046] Then, the irrationality of w

[0047] Then, the irrationality of w

[0048] Finally, the rationality of w

[0049] Therefore, the single segment bag length is equal to the daily progress of the roadway, which is the only solution to meet the requirements of advanced pressure relief theory, ensure the safety of excavation, and make the system operable. This design is the key to whether this scheme can be transformed from a concept to a reliable engineering practice.

[0050] The number of distributed water injection bags is preliminarily determined as N, and the calculation formula is as follows:

[0051] N = [D / L] (1)

[0052] In the formula, [] represents the down rounding operation, D is the total length of the long distance directional pressure relief borehole 16, and L is the design length of the single segment bag.

[0053] If all N segments of the bag are completed, the length of the borehole covered is N*L. The initial length of the exposed segment of the outermost segment of the borehole without the bag is D-N*L. The treatment of this exposed segment interval is determined according to its relationship with the depth S of the plastic zone of the roadway head: if D-N*L≤S, it is considered that this segment is completely within the plastic zone range, and the surrounding rock has yielded and unloaded, so no additional bag is arranged. If D-N*L>S, there is an elastic zone with a length of D-N*L-S in the segment. To effectively control the deformation of the surrounding rock in this part of the elastic zone, a segment of distributed water injection bags needs to be added. The length of this segment of bags is determined as D-N*L to completely cover the elastic zone segment.

[0054] The initial water injection pressure of the distributed water injection bag is set to 2-3 MPa.

[0055] This initial water injection pressure is sufficient to fully expand the bag to fit the borehole wall. When the surrounding rock of the borehole deforms and converges inward, according to Pascal's principle, due to the incompressibility of the fluid, the water pressure inside the bag will passively increase at a very high speed, thereby exerting a continuously increasing radial support reaction on the borehole wall, effectively inhibiting the instability of the borehole and maintaining the long-term effectiveness of the pressure relief channel. Therefore, it is unnecessary to pursue an unnecessarily high initial pressure that leads to unnecessary cost waste.

[0056] Step four: long-distance directional pressure relief borehole construction:

[0057] After determining the arrangement parameters of the directional pressure relief borehole, a long-distance directional pressure relief borehole is constructed according to the design. The construction time should ensure that it does not affect the start time of the planned excavation of the roadway to be excavated.

[0058] Step five: distribution of water injection bags:

[0059] Connect each segment of the bag to the water injection pipe, and then fix the water outlet pipe 3 of each segment of the bag to the water injection pipe. After the long-distance directional pressure relief borehole is constructed in place, push each segment of the bag along with the water injection pipe into the long-distance directional pressure relief borehole and spread it out, and then inject water into the bag through the water injection pipe until the bag reaches the set water injection pressure.

[0060] Step six: roadway excavation:

[0061] When the roadway first starts to excavate, open the water outlet pipe ball valve 2 of all the outermost bags of the long-distance directional pressure relief borehole to drain water, push the unloaded bags along with the water outlet pipe 3 to a distance S from the adjacent pressurized bag, and then start excavation. Stop excavating when the excavation reaches a distance S from the adjacent pressurized bag.

[0062] After stopping the tunneling, the bag previously pushed to the place is removed together with the water outlet pipe and the one-way valve 5 on the water injection pipe 1 for recycling, then the water is discharged by opening the water outlet pipe ball valve 2 of the adjacent pressurized bag, and the pressure-released bag is pushed to the next pressurized bag S, then the tunneling continues, and the tunneling stops after the tunneling L. The above process is repeated until the tunneling reaches the designed position.

[0063] The structure of the water injection bag system is as follows: comprising a water injection pipe 1, and sequentially connected one-way valves 5, bags, water outlet pipes 3, and ball valves 2.

[0064] When water injection, water enters each bag through the one-way valves 5 along the water injection pipe 1, forming water injection bags 4.

[0065] When water discharge, the water outlet pipe ball valve 2 is opened, and water flows out along the water outlet pipe 3, realizing pressure release.

[0066] The long-distance directional pressure release drilling hole has a diameter of 120mm-200mm.

[0067] The length of the distributed water injection bag 4 is consistent with the daily footage, and is L. After the tunneling is completed, the actual length of the bare hole segment in front of the head can always be dynamically equal to the theoretical length of the advanced pressure release.

[0068] The length of the water outlet pipe is consistent with the advanced pressure release distance, and is S, facilitating the water outlet pipe ball valve to be exposed after tunneling, so that the valve is opened for effective pressure release.

[0069] The distance between the one-way valve 5 and the bottom of the bag is consistent with the advanced pressure release distance, and is S, facilitating the one-way valve 5 on the water injection pipe to be exposed after tunneling, so that the bag together with the water outlet pipe and the one-way valve on the water injection pipe can be removed for recycling.

[0070] The present application has been practiced in a coal mine. The coal seam of the mine is an impact ground pressure coal seam, the buried depth is 1000m, the thickness is 4.5m, the to-be-excavated working face is the 2203 working face, and the design length of the to-be-excavated transportation crossheading is 600m. The to-be-excavated transportation crossheading is taken as an example for description.

[0071] Step one: long-distance directional pressure release drilling arrangement parameter determination:

[0072] According to the comprehensive index method, it is determined that the to-be-excavated transportation crossheading has weak impact danger, and two long-distance directional pressure release drillings need to be constructed at the head of the tunneling working face. The pressure release drillings are located in the working face of the head of the roadway, and according to the cross section size, two drillings are determined to be located on the two sides of the center line of the roadway with a spacing of 1.5m and a distance of 1.0m from the roadway floor. The length of a single long-distance directional pressure release drilling is 630m.

[0073] Step two: working face tunneling parameter determination:

[0074] According to the impact risk assessment results and geological conditions, the daily footage of the transportation crossheading is determined to be 8 m. The peak support pressure of the drilling method is determined to be 9 m (the depth of the plastic zone) from the coal wall, so that the advanced pressure relief distance S is 9 m.

[0075] Step three: distributed water injection bag parameter determination:

[0076] The length of the distributed water injection bag is consistent with the daily footage, which is 8 m.

[0077] According to the length of the long-distance directional pressure relief borehole, it is preliminarily determined that the number of distributed water injection bags required for a single long-distance directional pressure relief borehole is 78.

[0078] The outermost length of the long-distance directional pressure relief borehole is 6 m, which is less than the depth of the plastic zone of 9 m, and the distributed water injection bag is not arranged.

[0079] The initial water injection pressure of the distributed water injection bag is set to 2 MPa.

[0080] Step four: long-distance directional pressure relief borehole construction:

[0081] According to the construction time of the long-distance directional pressure relief borehole, the installation time of the distributed water injection bag, and the planning excavation time of the transportation crossheading, it is determined that the construction time of the long-distance directional pressure relief borehole is 15 days before the planning excavation start time of the transportation crossheading.

[0082] Step five: distributed water injection bag arrangement:

[0083] Connect each section of the bag with the water injection pipe, and then fix the water outlet pipe of each section of the bag to the water injection pipe. After the long-distance directional pressure relief borehole is constructed in place, push each section of the bag and the water injection pipe into the long-distance directional pressure relief borehole, and then spread them out. Then, inject water into the bag through the water injection pipe until the bag reaches 2 MPa and stops injecting water.

[0084] Step six: roadway excavation:

[0085] When the roadway first starts to excavate, open the water outlet pipe ball valve of the outermost distributed water injection bag in the two long-distance directional pressure relief boreholes at the excavation head, drain the water in it, complete the pressure relief of the borehole, and push the relieved bag and the water outlet pipe to 9 m away from the adjacent pressurized bag. Then start excavating, and stop excavating when the excavation reaches 9 m away from the adjacent pressurized bag.

[0086] After stopping excavation, remove the bag previously pushed to this position, as well as the water outlet pipe and the one-way valve on the water injection pipe, and recycle the distributed water injection bag. Then open the water outlet pipe ball valve of the adjacent pressurized bag to drain water, and push the bag and the water outlet pipe to 9 m away from the next pressurized bag. Then continue excavating, and stop excavating after excavating L. Repeat the above process until the excavation reaches the designed position.

[0087] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for preventing and treating head-on rock burst disasters at a tunneling working face, characterized in that: The steps of the method are: S1, determining the number and position of long-distance directional pressure relief boreholes in the heading face, then determining the face excavation parameters and the water injection bag distribution parameters according to the face excavation parameters; drilling long-distance directional pressure relief boreholes according to the face excavation parameters, then arranging the water injection bags according to the water injection bag distribution parameters, and injecting water to the water injection bags until the set water injection pressure is reached; S2, when the roadway starts to be excavated, the outermost water injection bag is drained and relieved, the drained and relieved water injection bag and the water outlet pipe are pushed to the adjacent water injection bag, and the excavation starts; S3, stopping the excavation, withdrawing the drained and relieved water injection bag, then draining and relieving the next water injection bag, pushing the drained and relieved water injection bag and the water outlet pipe to the adjacent water injection bag, and starting the next section of excavation; S4, repeating step S3 until the designed position is excavated.

2. The method according to claim 1, characterized in that: In step S1, the principle for determining the number of long-distance directional pressure relief boreholes in the heading face is: two long-distance directional pressure relief boreholes are drilled in the heading face of a roadway with weak impact risk, three long-distance directional pressure relief boreholes are drilled in the heading face of a roadway with medium or above impact risk, and the position of the long-distance directional pressure relief borehole in the heading face is determined according to the cross-sectional size of the heading face of the roadway.

3. The method according to claim 2, characterized in that: The position of the long-distance directional pressure relief borehole in the heading face is determined according to the cross-sectional size of the heading face of the roadway. When the distance between adjacent long-distance directional pressure relief boreholes is 0.8-1.2 m and there are two boreholes, the two long-distance directional pressure relief boreholes are symmetrically distributed along the vertical symmetry axis of the heading face, and the distance from the floor is 0.5-1.5 m. When the distance between adjacent long-distance directional pressure relief boreholes is 0.8-1.2 m and there are three boreholes, the three boreholes are arranged in a three-flower pattern, that is, one borehole is arranged on the vertical symmetry axis based on the two boreholes, and the borehole is located above the two boreholes. The diameter of the directional pressure relief borehole in the heading face is 120-200 mm.

4. The method of claim 1, wherein the method further comprises: In step S1, the method for determining the face excavation parameters and the water injection bag distribution parameters is: S101, in the face excavation parameters, the daily advance is L, the advance pressure relief distance is S, the length of the bare hole section not supported by the water injection bag in the hole is q, and the length of a single water injection bag is w; to ensure consistency in the initial state, the length of the outermost section not supported by the water injection bag in the initial state is also S, that is, the advance pressure relief distance is S; S102, to ensure the reliability of pressure relief, q≥S is always true during the entire excavation process; to ensure the consistency of theory and practice, q=S is always true during the entire excavation process; S103, after a section of water injection bags is relieved and the face is excavated by L, q=S+w-L, if w If w > L, there is q = S + w - L > S, which violates the consistency of theory and practice; this situation causes the length of the bare hole section to continue to accumulate after multiple cycles, and the system state gradually deviates from the original design; and the deeper bare hole section, the drilling of this section is prone to collapse failure due to ground pressure for a long time, which makes the pre-designed pressure relief channel unable to play a pressure relief role; Then it can be determined that w = L, and after the pressure relief section of the water injection bag is injected and L distance is excavated, q = S + w - L = S; this makes the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section in front of the heading always accurately restored to S after the excavation is completed, and the actual length of the bare hole section ​ 5. The method of claim 1, wherein the method further comprises: ​ ​ 6. The method of claim 1, wherein the method further comprises: ​ ​ 7. A water injection bag system for use in a method of preventing and controlling face-to-face rock burst disasters in a tunneling face according to any one of claims 1 to 6, characterized in that: ​

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