Method for determining position of floor pressure-relief roadway and comprehensive treatment method for rock burst and gas

Abstract

The present invention belongs to the field of prevention and control of coal mine rock bursts and gas, and specifically relates to a method for determining the position of a floor pressure-relief roadway and a comprehensive management method for rock bursts and gas. The method for determining the position of the floor pressure-relief roadway takes into account the strength of each rock layer in the floor, and based on the different strengths, the concept of virtual thickness is proposed, which can more accurately determine the maximum depth of the longitudinal fissures in the floor and provide a basis for determining the position of the floor pressure-relief roadway. The comprehensive management method for rock bursts and gas connects the floor pressure-relief roadway to the corresponding position of the O-ring of the coal seam through cross-cut boreholes. It serves both as a pressure-relief and pre-drainage roadway before mining and as a drainage roadway during the coal face mining, reducing the overall roadway construction volume while ensuring the prevention and control effects of rock bursts and gas.

Description

Technical Field

[0001] The invention belongs to the field of coal mine rock burst and gas prevention and control, and specifically relates to a method for determining the position of a bottom plate pressure relief tunnel and a method for comprehensive rock burst and gas control. Background Art

[0002] Coal seams deep underground will suddenly burst into free space under the action of stratum pressure, causing impact. When there is gas in the coal seam, the gas will also generate pressure, and produce coal and gas outbursts together with the coal. In order to recover safely, it is a common method to relieve the pressure of the coal seam and extract the gas.

[0003] In the prior art, top extraction tunnels are commonly used gas extraction measures, which are used to extract gas during the mining process of the working face. However, top extraction tunnels are generally constructed in the roof rock layer, which is greatly affected by mining and has serious air leakage. The gas content in the extracted air is low. Although it can achieve the purpose of gas prevention and control, the gas extraction workload is large and the control efficiency is low. In order to ensure the stability of the top extraction tunnel, the top extraction tunnel is generally constructed in the hard rock layer of the roof rock layer, which makes excavation difficult.

[0004] The decompression method of coal seams generally includes the construction of roof decompression tunnel or floor decompression tunnel, and then the construction of through-layer drilling holes from the roof decompression tunnel or floor decompression tunnel to decompress and pre-extract gas from the coal seams. However, there are few technologies that combine roof decompression tunnel with top extraction tunnel. Considering that the fracture development of the bottom rock layer is significantly worse than that of the roof rock layer, there is little research on the layout of the bottom extraction tunnel, and there is no precedent for the use of the bottom decompression tunnel as the extraction tunnel during the mining process of the working face. If the top extraction tunnel and the floor decompression tunnel are constructed at the same time, or if the top extraction tunnel and the roof decompression tunnel are constructed at the same time, the tunnel excavation workload will be large and the feasibility will be low. Drilling along the layer can also decompress and pre-extract gas from the coal seam, and the decompression effect is better, but it needs to be constructed in the horizontal tunnel after the construction of the working face horizontal tunnel is completed, so there is also a risk of rock burst during the excavation of the working face horizontal tunnel.

[0005] In summary, there are many existing rock burst prevention and control technologies and gas control technologies, but the comprehensive rock burst and gas prevention and control technologies are insufficient. If rock burst and gas control are carried out separately, there will be many construction processes and low efficiency. If through-layer drilling is used to relieve coal seam pressure and pre-extract gas, gas extraction is still required during the mining of the working face due to the limited gas extraction volume of gas pre-extraction. In addition, there is little research on bottom extraction lanes and bottom plate pressure relief lanes, and there is a lack of reference. The layout of bottom extraction lanes and bottom plate pressure relief lanes needs to be further explored. Summary of the invention

[0006] Aiming at the problems of complex and low-efficiency existing comprehensive prevention and control technologies for coal and gas, the present invention proposes a comprehensive management method for rock burst and gas, which uses the floor pressure relief roadway as both the pressure relief and pre-drainage roadway before mining and the drainage roadway during the coal face mining, reducing the overall roadway construction volume while ensuring the prevention and control effects of rock burst and gas. In addition, the present invention also provides a method for determining the position of the floor pressure relief roadway for comprehensive management of rock burst and gas, which minimizes the tunneling workload on the basis of ensuring the roadway stability.

[0007] Specifically, the method for determining the position of the floor pressure relief roadway for comprehensive management of rock burst and gas in the present invention includes the following steps:

[0008] S1. Determine the coal seam burial depth m and the working face width l; determine the thickness h i , unit weight r i and uniaxial compressive strength R i of each floor rock layer; i represents the i-th floor rock layer from top to bottom;

[0009] S2. Calculate the average unit weight r j of the floor rock layer, which is calculated by multiplying the thickness h i of each rock layer by the unit weight r i of the corresponding rock layer, summing them up, and then dividing by the total thickness of the floor rock layer;

[0010] S3. Calculate the average uniaxial compressive strength R j of the floor rock layer, which is calculated by multiplying the thickness h i of each rock layer by the uniaxial compressive strength R i of the corresponding rock layer, summing them up, and then dividing by the total thickness of the floor rock layer;

[0011] S4. Use the formula H = 1.57r j 2 m 2 l / (4R j 2 ) to calculate the maximum depth of the longitudinal fissure in the floor. In the formula, H is the maximum depth of the longitudinal fissure in the floor, m; r j is the average unit weight of the floor rock layer, 10 6 N / m 3 ; m is the coal seam burial depth, m; l is the working face width, m; R j is the average uniaxial compressive strength of the floor rock layer, MPa;

[0012] S5. Construct the floor pressure relief roadway in the rock layer that is the second closest to the maximum depth H of the longitudinal fissure in the floor at a depth deeper than the maximum depth H of the longitudinal fissure in the floor.

[0013] The method for determining the position of the floor pressure relief roadway for comprehensive management of rock burst and gas in the present invention can also be calculated in the following way, including the following steps:

[0014] S1. Determine the burial depth m of the coal seam and the working face width l; determine the thickness h of each rock stratum in the floor i , unit weight r i and uniaxial compressive strength R i ; i represents the i-th floor rock stratum from top to bottom;

[0015] S2. Calculate the average unit weight r of the floor rock stratum j , using the thickness h of each rock stratum i multiplied by the unit weight r of the corresponding rock stratum i sum, and then divide by the total thickness of the floor rock stratum for calculation;

[0016] S3. Determine the rock stratum with the minimum uniaxial compressive strength R in the floor rock stratum. The thickness of this rock stratum is taken as the original thickness, and the thicknesses of the remaining rock strata are taken as virtual thicknesses. The virtual thickness of a certain rock stratum in the remaining rock strata is equal to the ratio of the uniaxial compressive strength R of this rock stratum to the minimum uniaxial compressive strength R min squared, and then multiplied by the original thickness of this rock stratum; i and the minimum uniaxial compressive strength R min ;

[0017] S4. Use the formula Hx = 1.57r j 2 m 2 l / (4R min 2 ) to calculate the maximum virtual depth of the floor longitudinal fissure. In the formula, Hx is the maximum virtual depth of the floor longitudinal fissure, m; r j is the average unit weight of the floor rock stratum, 10 6 N / m 3 ; m is the burial depth of the coal seam, m; l is the working face width, m; R min is the minimum uniaxial compressive strength of the floor rock stratum, MPa;

[0018] S5. Determine which floor rock stratum the maximum virtual depth Hx of the floor longitudinal fissure is located in, and construct a floor pressure relief roadway in the rock stratum that is the second closest to this rock stratum from below.

[0019] The comprehensive control method for rock burst and gas of the present invention includes the following steps:

[0020] S1. Predict the range of the O-ring and the range of the compacted area along the working face width direction after coal seam mining;

[0021] S2. Predict the maximum depth of the floor longitudinal fissure;

[0022] S3. In the middle of the compaction area, in a certain rock stratum outside the maximum depth of the longitudinal floor fissure, a floor pressure relief roadway is constructed along the advancing direction of the working face. From the floor pressure relief roadway, cross-cutting boreholes are drilled towards both sides in the O-ring shape. The cross-cutting boreholes are drilled into the coal seam, and the cross-cutting boreholes are used to pre-crack and relieve the pressure of the coal seam, and then gas pre-extraction is carried out on the coal seam;

[0023] Preferably, in steps S2 - S3, the maximum depth of the longitudinal floor fissure and the vertical horizon of the floor pressure relief roadway are determined by using the floor pressure relief roadway position determination method described above;

[0024] S4. The driving face is retreated using the transportation roadway and the return airway, and the cutting eye is driven to connect the transportation roadway and the return airway;

[0025] Preferably, in step S4, from the transportation roadway and / or the return airway, a bedding borehole is drilled into the coal seam to pre-crack and relieve the pressure at the corresponding position in the compaction area of the coal seam.

[0026] S5. From the cutting eye towards the stop line direction, the coal seam is mined along the strike of the working face. After the working face is mined, a goaf is formed. The goaf is divided into an O-ring and a compaction area along the dip of the working face;

[0027] S6. The floor pressure relief roadway is used for gas extraction.

[0028] Preferably, in step S6, a fixed sealing door is arranged at one end of the floor pressure relief roadway close to the stop line, and a movable sealing door is arranged behind the coal mining position. Large-diameter ventilation holes are arranged on both sealing doors, and a large-diameter extraction pipe can be connected to the large-diameter ventilation holes on both sealing doors; when the coal mining class is mining coal, the sealing doors are closed, and gas extraction is carried out using the large-diameter extraction pipe; during the maintenance class, the sealing doors are opened, and gas extraction is directly carried out using the entire floor pressure relief roadway; the movable sealing door is located directly below the position where the next periodic weighting will occur.

[0029] The beneficial technical effects of the present invention are as follows: 1. The floor pressure relief roadway position determination method of the present invention can determine the maximum depth of the longitudinal floor fissure as accurately as possible. Especially the determination method based on the virtual thickness is also very accurate for the calculation of working conditions with large differences in rock stratum strength, providing a basis for the determination of the floor pressure relief roadway position.

[0030] 2. The floor pressure relief roadway of the present invention is constructed deeper than the maximum depth of the longitudinal floor fissure, reducing the influence of coal seam mining on it, facilitating the maintenance and stability of the roadway. And because the development depth of the floor fissure is small, the construction distance of the floor pressure relief roadway from the coal seam is close, which can reduce the construction volume of cross-cutting boreholes; the cross-cutting boreholes of the present invention are only constructed in the O-ring area, and pre-pressure cracking and pressure relief and gas pre-extraction are carried out on the coal seam corresponding to the O-ring area, preventing coal and gas outburst phenomena during the construction of the transportation roadway and the return airway.

[0031] 3. During the coal face mining process, a floor pressure relief roadway and cross-cut boreholes are used to continue gas drainage. The cross-cut boreholes are connected to the O-ring. The void in the goaf is relatively large within the O-ring and has strong connectivity, which is the main accumulation area of gas and is conducive to gas drainage.

[0032] 4. The present invention divides gas drainage into coal mining shifts and maintenance shifts and adopts different drainage schemes. During the coal mining shift, a large amount of gas is generated, and concentrated wind power is used to drain it. During the maintenance shift, the entire area is drained, and the corresponding positions of the O-ring in the unmined area are further pre-drained, and the corresponding positions in the compacted area are pre-drained. Description of the Drawings

[0033] Figure 1 is a schematic diagram of the inclined section layout of the floor pressure relief roadway of the present invention (in the direction of the working face width);

[0034] Figure 2 is a schematic diagram of the strike section layout of the floor pressure relief roadway of the present invention (in the direction of the working face advancement);

[0035] In the figure, coal seam 1, O-ring 2, compacted area 3, floor pressure relief roadway 4, cross-cut borehole 5, maximum depth of the longitudinal floor crack 6, sealing door 7, large-diameter drainage pipe 8, coal pillar 9, goaf 10. Detailed Embodiment

[0036] The following combines the attached Figure 1-2 to elaborate on the specific embodiments of the present invention in detail.

[0037] Aiming at the problems of the existing comprehensive prevention and control technology for coal and gas being complex and inefficient, the present invention proposes a comprehensive management method for rock burst and gas, using the floor pressure relief roadway as both the pressure relief and pre-drainage roadway before mining and the drainage roadway during the coal face mining, reducing the overall roadway construction volume while ensuring the prevention and control effects of rock burst and gas; in addition, the present invention also provides a method for determining the position of the floor pressure relief roadway for comprehensive management of rock burst and gas, minimizing the tunneling workload to the greatest extent on the basis of ensuring the stability of the roadway.

[0038] Embodiment 1

[0039] A comprehensive management method for rock burst and gas, as Figure 1-2 shown, includes the following steps:

[0040] S1. Estimate the range of the O-ring 2 and the range of the compacted area 3 along the width direction (incline) of the working face after the coal seam 1 is mined. The compacted area 3 generally refers to the goaf area that has returned to the original rock stress or the goaf area that is close to (in this embodiment, 85% or more) returning to the original rock stress, or refers to the area where the broken rock mass in the goaf caving zone has a relatively high degree of relative compression; the range of the O-ring 2 can refer to the range between the compacted area 3 and the coal pillar 9, and the range of the O-ring 2 can also be determined with reference to existing literature;

[0041] S2. It is estimated that the maximum depth of the longitudinal fissure in the floor is 6, which can be determined by referring to existing literature or by means of numerical simulation and physical simulation;

[0042] S3. In the middle of the compaction zone 3, outside the maximum depth 6 of the longitudinal fissure in the floor, preferably in a certain soft rock layer (such as mudstone or sandy mudstone), or in the rock layer that is the second closest to the maximum depth 6 of the longitudinal through fissure in the floor, a floor pressure relief roadway 4 is constructed along the working face advancing direction. Cross-cutting boreholes 5 are constructed from the floor pressure relief roadway 4 to both sides of the O-ring 2. The cross-cutting boreholes 5 are constructed into the coal seam 1 and penetrate the entire coal seam 1. The coal seam 1 is pre-cracked and pressure relieved (such as by hydraulic fracturing or blasting-induced fracturing) using the cross-cutting boreholes 5, and then gas pre-extraction is carried out on the coal seam 1;

[0043] S4. The heading face is retreated using the transportation roadway and the return airway. The cutting eye connects the transportation roadway and the return airway. Since the pressure relief and pre-extraction area carried out using the cross-cutting boreholes 5 is located in the O-ring, and the transportation roadway and the return airway are located at the boundary of the O-ring, coal and gas outburst accidents will not occur during the excavation of the transportation roadway and the return airway;

[0044] Cross-seam boreholes are constructed from the transportation roadway and / or the return airway into the coal seam 1 to pre-crack and pressure relieve the corresponding position in the compaction area of the coal seam 1;

[0045] S5. From the cutting eye towards the stop line direction, that is, along the working face strike, the coal seam 1 is mined. After the working face is mined, a goaf 10 is formed. The goaf 10 is divided into the O-ring 2 and the compaction zone 3 along the working face dip (the working face width direction);

[0046] S6. A fixed seal door 7 is arranged at one end of the floor pressure relief roadway 4 close to the stop line, and a movable seal door 7 is arranged directly below the periodic weighting position behind the coal mining position. Both seal doors 7 can be opened, and large-diameter ventilation holes are arranged on both seal doors 7. A large-diameter extraction pipe 8 can be connected to the large-diameter ventilation holes on both seal doors; the movable seal door is directly below the position where the current periodic weighting will occur;

[0047] During coal mining in the coal mining shift, gas overflows from the broken coal body, and the gas overflow is large. Therefore, the seal door 7 is closed, and the large-diameter extraction pipe 8 is mainly used to extract gas in the O-ring 2. The gas generated during the coal breaking process can be extracted through the O-ring 2, the cross-cutting boreholes 5, the floor pressure relief roadway 4, and the large-diameter extraction pipe 8;

[0048] During the maintenance shift, coal mining work is not carried out. After coal mining in the coal mining shift, the stress of the coal seam in the front side waiting to be mined changes, and gas overflows. The seal door 7 is opened, and gas extraction is directly carried out using the entire floor pressure relief roadway 4 and all cross-cutting boreholes 5;

[0049] Repeat this process until the entire working face is mined out.

[0050] The floor pressure relief roadway 4 of the present invention is constructed at a depth greater than the maximum depth of the longitudinal fissures in the floor, reducing the impact of coal seam mining on it, facilitating the maintenance and stability of the roadway. Moreover, due to the small depth of floor fissure development, the floor pressure relief roadway is constructed close to the coal seam, which can reduce the construction volume of cross-cut boreholes. The cross-cut boreholes of the present invention are only constructed in the O-ring area to pre-fracture and depressurize the coal seam in the area corresponding to the O-ring and pre-drain gas, preventing coal and gas outburst phenomena during the construction of the transportation roadway and the return airway. During the coal face mining process, the floor pressure relief roadway and cross-cut boreholes are used to continue gas drainage, which is equivalent to the function of the top-drainage roadway. The cross-cut boreholes are connected to the O-ring, and the voids in the goaf are relatively large in the O-ring area with strong connectivity, which is the main accumulation area of gas and is easy for gas drainage. The gas drainage is divided into the coal mining shift and the maintenance shift, and different drainage schemes are adopted. The gas generation amount is large in the coal mining shift, and concentrated wind force is used to drain it. The maintenance shift drains the entire area, further pre-drains the corresponding positions of the O-ring in the unmined area, and pre-drains the corresponding positions of the compacted area (the fissures formed by pre-fracturing the cross-cut boreholes and the bedding boreholes can penetrate).

[0051] Embodiment 2

[0052] A method for determining the position of a floor pressure relief roadway for comprehensive treatment of rock burst and gas includes the following steps:

[0053] S1. Determine the burial depth m of the coal seam and the width (dip) l of the working face; determine the thickness h of each floor rock layer i , bulk density r i and uniaxial compressive strength R i ; i represents the i-th floor rock layer from top to bottom;

[0054] S2. Calculate the average bulk density r of the floor rock layer j . Since the bulk densities of rock layers with different lithologies do not differ much, the bulk density of each floor rock layer can be calculated using the average bulk density r j . Specifically, multiply the thickness h of each rock layer i by the corresponding bulk density r i and sum them, then divide by the total thickness ∑h of the floor rock layer i ; that is

[0055] r j =∑h i r i / ∑h i

[0056] S3. Calculate the average uniaxial compressive strength R of the floor rock layer j . The uniaxial compressive strength of each floor rock layer is calculated using the average uniaxial compressive strength R j . Specifically, use the thickness h of each rock layeri Multiply by the uniaxial compressive strength R of the corresponding rock stratum i Sum them up, and then divide by the total thickness ∑h of the floor rock stratum i ; that is

[0057] R j = ∑h i R i / ∑h i

[0058] S4. Use the formula H = 1.57r j 2 m 2 l / (4R j 2 ) to calculate the maximum depth 6 of the longitudinal floor fissure. In the formula, H is the maximum depth of the longitudinal floor fissure, m; r j is the average unit weight of the floor rock stratum, 10 6 N / m 3 ; m is the burial depth of the coal seam, m; l is the working face width, m; R j is the average uniaxial compressive strength of the floor rock stratum, MPa;

[0059] S5. At a depth deeper than the maximum depth H of the longitudinal floor fissure, select the hard rock stratum closest to the maximum depth H of the longitudinal floor fissure. Construct the floor pressure relief roadway 4 in the soft rock stratum immediately below the hard rock stratum, and the top of the floor pressure relief roadway is not more than 10 m away from the maximum depth H of the longitudinal floor fissure. If it exceeds 10 m, select the second-closest rock stratum to the maximum depth H of the longitudinal floor fissure to construct the floor pressure relief roadway 4.

[0060] In Example 1, step S2 can use steps S1 - S4 in Example 2 to determine the maximum depth 6 of the longitudinal floor fissure. In Example 1, step S3 can use step S5 in Example 2 to determine the vertical horizon of the floor pressure relief roadway 4.

[0061] Example 3

[0062] A method for determining the position of the floor pressure relief roadway for comprehensive control of rock burst and gas includes the following steps:

[0063] S1. Determine the burial depth m of the coal seam and the working face width (dip) l; determine the thickness h i , unit weight r i and uniaxial compressive strength R i of each floor rock stratum; i represents the i-th floor rock stratum from top to bottom;

[0064] S2. Calculate the average unit weight r j of the floor rock stratum. Since the unit weights of rock strata with different lithologies do not differ much, the average unit weight r j of each floor rock stratum can be used for calculation. Specifically, use the thickness hi Multiply by the unit weight r of the corresponding rock stratum i Sum them up, and then divide by the total thickness ∑h of the floor rock stratum i ; that is

[0065] r j = ∑h i r i / ∑h i

[0066] S3. Determine the uniaxial compressive strength R of the rock stratum in the floor min For the rock stratum with the minimum uniaxial compressive strength, the thickness of this rock stratum is taken as the original thickness, and the thicknesses of the remaining rock strata are taken as virtual thicknesses. The virtual thickness of a certain rock stratum in the remaining rock strata is equal to the square of the ratio of the uniaxial compressive strength R of this rock stratum to the minimum uniaxial compressive strength, and then multiplied by the original thickness of this rock stratum, that is, the virtual thickness h of a certain rock stratum is obtained i = h xi h i R i 2 / R min 2 ;

[0067] S4. Use the formula Hx = 1.57r j 2 m 2 l / (4R min 2 ) to calculate the maximum virtual depth of the longitudinal crack in the floor. In the formula, Hx is the maximum virtual depth of the longitudinal crack in the floor, m; r j is the average unit weight of the floor rock stratum, 10 6 N / m 3 ; m is the burial depth of the coal seam, m; l is the working face width, m; R min is the minimum uniaxial compressive strength of the floor rock stratum, MPa;

[0068] S5. Determine in which floor rock stratum the maximum virtual depth Hx of the longitudinal crack in the floor is located according to the virtual thickness of the floor rock stratum (the virtual thickness of the rock stratum with the minimum uniaxial compressive strength is equal to the actual thickness). This rock stratum is the rock stratum where the maximum depth H of the longitudinal crack in the floor is located; it is also possible to reverse the actual depth of the longitudinal crack in this rock stratum based on the virtual depth of the longitudinal crack in the floor rock stratum where the maximum depth 6 of the longitudinal crack in the floor is located, and add the sum of the actual thicknesses of the upper floor rock strata to obtain the maximum depth H of the longitudinal crack in the floor; xi = h i R i 2 / R min 2

[0069] ​S6. Below the maximum depth H of the longitudinal fissure in the floor, select the hard rock layer (which is a hard rock layer) that is the closest to the maximum depth H of the longitudinal fissure in the floor or the rock layer where the maximum depth H of the longitudinal fissure in the floor is located. Construct the floor pressure-relief roadway 4 in the soft rock layer immediately below this hard rock layer, and the top of the floor pressure-relief roadway is no more than 10 m away from the maximum depth H of the longitudinal fissure in the floor. If it exceeds 10 m, then select the rock layer that is the second closest to the rock layer where the maximum depth H of the longitudinal fissure in the floor is located to construct the floor pressure-relief roadway 4.

[0070] In step S2 of the first embodiment, the maximum depth 6 of the longitudinal fissure in the floor can be determined by using steps S1 - S5 of the third embodiment (based on the virtual depth of the longitudinal fissure in the floor in the rock layer where the maximum depth 6 of the longitudinal fissure in the floor is located, and according to the formula h xi = h i R i 2 / R min 2 inversely deduce the actual depth of the longitudinal fissure in this rock layer, and add the actual thickness of the upper floor rock layer to obtain the maximum depth H of the longitudinal fissure in the floor) or the rock layer where the maximum depth 6 of the longitudinal fissure in the floor is located. In step S3 of the first embodiment, the vertical layer position of the floor pressure-relief roadway 4 can be determined by using step S6 of the third embodiment.

[0071] Since the uniaxial compressive strengths of different rock layers vary greatly, even by several times, if the method in the second embodiment is adopted and the average uniaxial compressive strength R j is used for calculation, a large error will be generated, and the construction layer position of the floor pressure-relief roadway will be deeper, more conservative, and the amount of cross-cut drilling construction will increase. Therefore, for the working conditions where the uniaxial compressive strengths of the floor rock layers vary greatly, the third embodiment can be used to calculate the maximum depth of the longitudinal fissure in the floor.

[0072] Of course, the above description is only the preferred embodiments of the present invention. The present invention is not limited to listing the above embodiments. It should be noted that all equivalent substitutions and obvious deformation forms made by any person skilled in the art under the guidance of this specification fall within the substantial scope of this specification and should be protected by the present invention.

Claims

1. Comprehensive control method for rock burst and gas, characterized in that, It includes the following steps: S1. Predict the range of the O-ring and the compacted area along the working face width direction after coal seam mining; S2. Predict the maximum depth of the longitudinal floor fissure; S3. In the middle of the compacted area, in a certain rock stratum outside the maximum depth of the longitudinal floor fissure, construct a floor pressure relief roadway along the working face advancing direction. Drill cross-cut holes from the floor pressure relief roadway to both sides of the O-ring. The cross-cut holes are drilled into the coal seam. Use the cross-cut holes to pre-crack and relieve the pressure of the coal seam, and then conduct pre-drainage of gas from the coal seam; S4. Drive the transportation roadway and the return airway for the return of the driving face, and drive the cutting eye to connect the transportation roadway and the return airway; Drill bedding holes from the transportation roadway and / or the return airway into the coal seam to pre-crack and relieve the pressure at the corresponding position of the compacted area in the coal seam; S5. From the cutting eye to the stop line direction, conduct coal seam mining along the working face strike. After the working face is mined, a goaf is formed. The goaf is divided into an O-ring and a compacted area along the working face dip; S6. Use the floor pressure relief roadway to conduct gas drainage; Among them, in steps S2 - S3, use the method for determining the position of the floor pressure relief roadway for comprehensive treatment of rock burst and gas to determine the maximum depth of the longitudinal floor fissure and the vertical horizon of the floor pressure relief roadway, including: Determine the burial depth \(m\) of the coal seam and the working face width \(l\); determine the thickness \(h\) of each rock stratum in the floor i , bulk density \(r\) i and uniaxial compressive strength \(R\) i ; \(i\) represents the \(i\)-th floor rock stratum from top to bottom; Calculate the average unit weight γ of the floor rock strata j , using the thickness h of each rock stratum i multiplied by the unit weight γ of the corresponding rock stratum i sum them up and then divide by the total thickness of the floor rock strata for calculation; Determine the uniaxial compressive strength R of the floor rock formation min For the thinnest rock formation, its thickness is taken as the original thickness, and for the remaining rock formations, their thicknesses are taken as virtual thicknesses. The virtual thickness of a certain rock formation among the remaining rock formations is equal to the square of the ratio of the uniaxial compressive strength of this rock formation to the minimum uniaxial compressive strength R min , and then multiplied by the original thickness of this rock formation; Use the formula Hx = 1.57r j 2 m 2 l / (4R min 2 ) to calculate the maximum virtual depth of the longitudinal crack in the floor. In the formula, Hx is the maximum virtual depth of the longitudinal crack in the floor, m; r j is the average unit weight of the floor rock stratum, 10 6 N / m 3 ; m is the burial depth of the coal seam, m; l is the working face width, m; R min is the minimum uniaxial compressive strength of the floor rock stratum, MPa; Determine which floor rock stratum the maximum virtual depth Hx of the longitudinal floor fissure is located in, and construct the floor pressure relief roadway in the rock stratum that is the second closest to this stratum below; 2. The comprehensive control method for rock burst and gas according to claim 1, wherein In step S6, arrange a fixed seal door at one end of the floor pressure relief roadway close to the stop line, and arrange a movable seal door behind the coal mining position. Large-diameter ventilation holes are provided on both seal doors. The large-diameter drainage pipe can be connected to the large-diameter ventilation holes on both seal doors; When the coal mining shift is mining coal, close the seal door and use the large-diameter drainage pipe to conduct gas drainage; During the maintenance shift, open the seal door and directly use the entire floor pressure relief roadway to conduct gas drainage; The movable seal door is located directly below the position where the next periodic weighting will occur.

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