Method for preventing rock burst

Abstract

The rock burst prevention and control method comprises the following steps that S1, a roof rock stratum with the thickness larger than or equal to a first preset value and the compressive strength larger than or equal to a second preset value above at least one of a to-be-treated roadway and a to-be-mined working face is divided into a rock burst disaster-caused master control rock stratum; s2, a drill hole is formed in the rock burst disaster-caused master control rock stratum; s3, hydraulic fracturing is conducted on the rock burst disaster-caused main control rock stratum through the drilled hole, so that a hydraulic fracture area with hydraulic fracturing fractures is formed in the rock burst disaster-caused main control rock stratum; and S4, a plurality of prevention and control caves communicating with hydraulic fracturing cracks are formed in the hydraulic fracture area of the rock burst disaster-caused master control rock stratum. According to the rock burst prevention method, the rock burst occurrence risk of the working face can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a method for preventing and controlling rock burst. Background Art

[0002] In the relevant technology, rock burst refers to the dynamic phenomenon of sudden and violent destruction of the rock mass around the shaft or working face due to the instantaneous release of elastic deformation energy, which is often accompanied by coal and rock mass ejection, loud noise and air waves. Rock burst accidents are characterized by a large degree of destruction and are the focus of roof disaster prevention and control. Rock burst often occurs in the roof, especially in coal seam tunnels with thick and hard roofs. Large-diameter drilling is often used in the prevention and control of rock burst. By drilling large-diameter holes in the coal seam to form stress release holes, the concentration of stress in the coal body is reduced and alleviated. This method can alleviate the high stress state of the coal body to a certain extent and reduce the impact risk. However, large-diameter drilling pressure relief in coal seams is a local relief measure for rock burst, which is difficult to improve the regional stress environment. Under high stress conditions, the pressure relief effect is limited. A large number of drilling holes may damage the integrity of the surrounding rock of the tunnel and have an adverse effect on the stability of the surrounding rock of the tunnel. The drilling project is large, interferes with normal production, and has low efficiency. Large-diameter drilling may also cause accidents such as coal and gas outbursts, increasing safety risks. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, an embodiment of the present invention provides a method for preventing and controlling rock burst.

[0004] The method for preventing and controlling rock burst in an embodiment of the present invention comprises the following steps: Step S1, classifying the roof rock layer above at least one of the tunnel to be treated and the working face to be mined, which has a thickness greater than or equal to a first preset value and a compressive strength greater than or equal to a second preset value, as the main rock layer causing rock burst disaster; Step S2, drilling a hole in the rock formation that controls the rock burst disaster; Step S3, hydraulically fracturing the main rock formation causing rock burst disaster by using the drill hole, so as to form a hydraulic fracture zone having hydraulic fractures in the main rock formation causing rock burst disaster; Step S4, opening a plurality of prevention and control caves connected to the hydraulic fracturing cracks in the hydraulic fracture area of ​​the main rock formation causing rock burst disaster.

[0005] In some embodiments, in step S4, rock is cut outward from the borehole located in the hydraulic fracture zone to open a plurality of control caves.

[0006] In some embodiments, the prevention cave comprises a first prevention cave; In the step S4, a position in the borehole located in the hydraulic fracture zone is taken as the center position of the first control cave, and then the rock is cut outward to form the first control cave.

[0007] In some embodiments, in step S4, a plurality of the first control caves are provided in the hydraulic fracture zone and distributed along the extension direction of the borehole.

[0008] In some embodiments, in step S4, the distance between two adjacent first prevention and control caves in the extension direction of the same borehole is greater than or equal to 10 meters.

[0009] In some embodiments, after hydraulic fracturing of the borehole is completed, rock is cut outward from multiple positions in the borehole in sequence in a direction away from the bottom of the borehole to open multiple control caves.

[0010] In some embodiments, the borehole is divided into a plurality of sub-boreholes along an extension direction of the borehole, and the plurality of sub-boreholes are hydraulically fractured in sequence along a direction away from the bottom of the borehole, wherein after hydraulic fracturing is completed on one of two adjacent sub-boreholes adjacent to the bottom of the borehole, rock is cut outward from inside one of the two adjacent sub-boreholes adjacent to the bottom of the borehole to open the control cave, and then hydraulic fracturing is performed on one of the two adjacent sub-boreholes away from the bottom of the borehole.

[0011] In some embodiments, the diameter of the prevention cave is greater than or equal to 1 meter; In the step S2, there are multiple drill holes, and the multiple drill holes are arranged at intervals; In step S4, a hydraulic ejector is delivered to the borehole in the hydraulic fracture zone by a drilling rig, and the hydraulic ejector ejects jet water having a pressure greater than or equal to a third preset value to the rock in the hydraulic fracture zone so as to cut the rock.

[0012] In some embodiments, in the step S1, the top rock layer above at least one of the tunnel to be treated and the working face to be mined, whose thickness is greater than or equal to a first preset value and whose compressive strength is greater than or equal to a second preset value, is divided into multiple layers of the main rock layer causing rock burst disaster; In the step S2, the drill hole is opened upward from the formed tunnel, the horizontal extension direction of the drill hole and the extension direction of the tunnel to be treated are both in the first direction, a plurality of the drill holes are arranged at intervals in the second direction, and any two of the first direction, the second direction and the up-down direction are perpendicular to each other; In step S4, the top of the prevention and control cave is located at the top of the rock formation that controls rock burst disasters, and the bottom of the prevention and control cave is located at the bottom of the rock formation that controls rock burst disasters; In step S4, the pressure of the jet water is greater than or equal to 50 MPa.

[0013] The method for preventing and controlling rock burst in an embodiment of the present invention also includes step S5. In step S5, after opening a plurality of the prevention and control caves, the working face to be mined is mined, and the rock burst prevention and control effect is evaluated based on microseismic monitoring during the mining process. The rock burst prevention and control effect can be improved by at least one of increasing the number of drill holes, increasing the number of the prevention and control caves, shortening the distance between two adjacent prevention and control caves, and increasing the hydraulic fracturing displacement.

[0014] The beneficial effect of the present invention is that: according to the rock burst prevention and control method of the embodiment of the present invention, a borehole is opened in the main rock formation that causes rock burst disaster and hydraulic fracturing is performed, so as to fully fracture the deep rock mass of the main rock formation that causes rock burst disaster, destroy its integrity and strength, and cause the main rock formation that causes rock burst disaster to break along the cracks and collapse in time during mining. After hydraulic fracturing, by opening a prevention and control cave in the main rock formation that causes rock burst disaster, a large-sized cavitation cavity can be formed in the main rock formation that causes rock burst disaster, so that stress is redistributed, a high stress relief effect is exerted, the rock mass is caused to displace, and the accumulated energy of the rock mass is effectively released. By utilizing the combined effects of hydraulic fracturing cracks and preventive caves, the hard and intact main rock strata that cause rock burst disasters are transformed into a relatively broken roof containing a large number of cavities. The transformed main rock strata that cause rock burst disasters are not prone to large-energy fracture events or induce strong dynamic load disturbances, and can serve as a buffer layer to absorb the impact energy generated by other rock strata, thereby reducing the risk of rock burst on the working face. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of opening a prevention and control cave according to the method for preventing and controlling rock burst in an embodiment of the present invention.

[0016] Figure 2 Schematic diagram of a fluidic tool string according to an embodiment of the present invention.

[0017] Figure numerals: 1. Main controlling rock layer for rock burst disaster, 2. Drill hole, 3. Hydraulic fracturing crack, 4. First prevention and control cave, 5. Safety handrail, 6. Hydraulic ejector, 7. Stabilizer, 8. Ball seat, 9. Push rod. DETAILED DESCRIPTION

[0018] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0019] The following describes the method for preventing and controlling rock burst according to an embodiment of the present invention with reference to the accompanying drawings. Figure 1 and Figure 2 As shown, the method for preventing and controlling rock burst according to an embodiment of the present invention comprises the following steps: Step S1, the roof rock layer above at least one of the tunnel to be treated and the working face to be mined, whose thickness is greater than or equal to the first preset value and whose compressive strength is greater than or equal to the second preset value, is classified as the main controlling rock layer 1 for rock burst disaster. Specifically, the occurrence parameters of the hard roof rock layer are analyzed according to the roof rock layer column chart. The roof rock layer is cored and rock physics and mechanics experiments are carried out to evaluate its impact tendency. Microseismic monitoring is a technology for detecting and analyzing small earthquake activities caused by rock fracture or stress changes. Through microseismic monitoring, changes in underground structures can be understood in real time, rock formation stability can be evaluated, and potential geological disasters can be predicted. Microseismic monitoring technology is used to monitor the seismic wave characteristics after the roof rock mass breaks, analyze the distribution position and event size of microseismic events, and combine the occurrence parameters of the roof rock layer, the rock formation impact tendency and the distribution of microseismic events to comprehensively judge whether the roof rock layer is the main controlling rock layer 1 for rock burst disaster, and prevent and control the impact of the main controlling rock layer 1 for rock burst disaster. For example, the roof rock layer above the tunnel to be managed and the working face to be mined, whose thickness is greater than or equal to the first preset value and whose compressive strength is greater than or equal to the second preset value, is classified as the main controlling rock layer 1 for rock burst disaster.

[0020] Step S2, opening a borehole 2 in the rock formation 1 that controls rock burst disasters. Specifically, in step S2, there are multiple boreholes 2, and the multiple boreholes 2 are arranged at intervals, so as to facilitate hydraulic fracturing of multiple positions of the rock formation 1 that controls rock burst disasters in the horizontal direction, so as to increase the range of the hydraulic fracturing cracks 3.

[0021] In some embodiments, in step S2, a borehole 2 is opened upward from the formed tunnel, the horizontal extension direction of the borehole 2 and the extension direction of the tunnel to be treated are both in the first direction, multiple boreholes 2 are spaced in the second direction, and any two of the first direction, the second direction and the up-down direction are perpendicular to each other. For example, the first direction is consistent with the direction of the coal seam, and the horizontal extension direction of the borehole 2 and the extension direction of the tunnel to be treated are both in the direction of the coal seam.

[0022] For example, a drilling site is arranged in the formed tunnel, and a thousand-meter directional drilling is used in the coal mine to open a borehole 2 in the main rock layer 1 that causes rock burst disasters. After the borehole 2 climbs to the main rock layer 1 that causes rock burst disasters, it turns to the horizontal plane. That is, the borehole 2 includes a climbing section and a horizontal section. The top of the climbing section is connected to the horizontal section, and the extension direction of the horizontal section is consistent with the extension direction of the tunnel to be treated. The size of the horizontal section in the first direction is greater than or equal to 300 meters and less than or equal to 1000 meters.

[0023] In some embodiments, the distance between two adjacent boreholes 2 in the second direction is greater than or equal to 30 meters and less than or equal to 50 meters, so that after hydraulic fracturing, the hydraulic fracturing cracks 3 can be distributed in the second direction in the area between two adjacent boreholes 2 in the rock formation 1 that controls rock burst disasters. For example, the distance between two adjacent boreholes 2 in the second direction is 40 meters.

[0024] Step S3, hydraulically fracturing the main rock formation 1 causing rock burst disaster by using the borehole 2, so as to form a hydraulic fracture zone with hydraulic fracture cracks 3 in the main rock formation 1 causing rock burst disaster. Specifically, hydraulically fracturing the main rock formation 1 causing rock burst disaster is performed, so that the main rock formation 1 causing rock burst disaster is cut off by the hydraulic fracture cracks 3, so as to fully fracture the main rock formation 1 causing rock burst disaster, destroy its integrity and strength, and thus relieve the pressure. For example, a directional drilling rig is used to send an expandable open hole packer into a specified position of the borehole 2, and a double-seal single-card staged fracturing process is adopted. Start the downhole hydraulic fracturing pump group to inject water into the isolation section for fracturing, and form large-area fractures in the main rock formation 1 causing rock burst disaster. After the fracturing is completed, the expandable open hole packer is depressurized and unsealed, and then the next staged fracturing operation is carried out.

[0025] Step S4, multiple prevention and control caves connected to the hydraulic fracture cracks 3 are opened in the hydraulic fracture area of ​​the main rock formation 1 causing rock burst disaster. That is to say, after the hydraulic fracture of the main rock formation 1 causing rock burst disaster is relieved, multiple holes are opened in the area (hydraulic fracture area) with hydraulic fracture cracks 3 in the main rock formation 1 causing rock burst disaster, so as to serve as prevention and control caves. Specifically, the diameter of the prevention and control cave is greater than or equal to 1 meter. For example, the diameter of the prevention and control cave is 2 meters, 3 meters, 5 meters, 8 meters or 10 meters.

[0026] According to the method for preventing and controlling rock burst in the embodiment of the present invention, a borehole 2 is opened in the main rock formation 1 causing rock burst disaster and hydraulic fracturing is performed, so as to fully fracture the deep rock mass of the main rock formation 1 causing rock burst disaster, destroy its integrity and strength, and cause the main rock formation 1 causing rock burst disaster to break along the cracks and collapse in time during mining. After hydraulic fracturing, a prevention and control cave is opened in the main rock formation 1 causing rock burst disaster, so that a large-sized cavitation cavity (free space) can be formed in the main rock formation 1 causing rock burst disaster, so that stress is redistributed, a high stress relief effect is exerted, the rock mass is caused to displace, and the accumulated energy of the rock mass is effectively released. By utilizing the combined effect of hydraulic fracturing cracks 3 and preventive caves, the hard and complete main rock stratum 1 causing rock burst disasters is transformed into a relatively broken roof containing a large number of cavities. The transformed main rock stratum 1 causing rock burst disasters is not prone to large-energy fracture events or strong dynamic load disturbances, and can serve as a buffer layer to absorb the impact energy generated by other rock strata, thereby reducing the risk of rock burst on the working face.

[0027] Therefore, the method for preventing and controlling rock burst according to the embodiment of the present invention can reduce the risk of rock burst occurring on the working face.

[0028] like Figure 1 and Figure 2 As shown, in some embodiments, in step S4, rock is cut outward from the borehole 2 located in the hydraulic fracture zone to open a plurality of control caves. Specifically, in step S4, a hydraulic ejector 6 is delivered to the borehole 2 located in the hydraulic fracture zone by a drilling rig, and the hydraulic ejector 6 sprays jet water with a pressure greater than or equal to a third preset value to the rock in the hydraulic fracture zone to cut the rock, thereby forming a control cave. Specifically, opening a control cave in the hydraulic fracture zone starting from a previously opened borehole 2 can reduce the construction difficulty. The drilling rig delivers the hydraulic ejector 6 to a designated position in the previously opened borehole 2 to cut the rock and form a control cave. For example, the drilling rig includes a ball seat 8, a push rod 9, a straightener 7 and a safety handrail 5 connected in sequence, and the hydraulic ejector 6 is connected to the push rod 9 to form a jet tool string, so that the drilling rig drives the hydraulic ejector 6 to move in the borehole 2.

[0029] In some embodiments, in step S4, the pressure of the jet water is greater than or equal to 50 MPa. For example, the pressure of the jet water is 80 MPa, 100 MPa or 120 MPa.

[0030] like Figure 1As shown, in some embodiments, the control cave includes a first control cave 4. In step S4, a position (preset position) in the borehole 2 located in the hydraulic fracture zone is used as the center position of the first control cave 4, and then the rock is cut outward to form the first control cave 4. As a result, the center position of the first control cave 4 can be located in the corresponding borehole 2, so that multiple first control caves 4 can be distributed along the borehole 2, and the construction difficulty can be reduced. For example, the hydraulic ejector 6 is a hydraulic spray gun, and the hydraulic spray gun is sent to the fracturing position of the borehole 2 by a drilling rig, the high-pressure water pump is connected to the drill rod, the hydraulic spray gun is installed, the water pump is started, and the water pressure is gradually increased to form a high-pressure water jet. The hydraulic spray gun is moved through the drill rod, and the rock is cut by an abrasive water jet to form a cavity centered on the borehole 2. A backward segmented hydraulic jet cavitation process is adopted, that is, the cavitation is sequentially segmented from the direction away from the bottom of the borehole 2.

[0031] like Figure 1 As shown, in some embodiments, in step S4, a plurality of first prevention and control caves 4 are provided in the hydraulic fracture area and are distributed along the extension direction of the borehole 2. Specifically, in step S4, the distance between two adjacent first prevention and control caves 4 in the extension direction of the same borehole 2 is greater than or equal to 10 meters. Providing a plurality of first prevention and control caves 4 in the extension direction of the borehole 2 can reduce the construction difficulty and improve the rock burst prevention and control effect.

[0032] In some embodiments, after hydraulic fracturing is completed in the borehole 2, the rock is cut outward from multiple positions in the borehole 2 in a direction away from the bottom of the borehole 2 to open multiple preventive caves. That is, after hydraulic fracturing is completed in the entire borehole 2, the preventive caves are opened. That is, after step S3 is completed, step S4 is performed.

[0033] In some embodiments, the prevention cave is located between two adjacent boreholes 2, so that a large-sized cavitation cavity (free space) can exist between the two adjacent boreholes 2, thereby facilitating pressure relief.

[0034] In some embodiments, the borehole 2 is divided into a plurality of sub-boreholes along the extension direction of the borehole 2, and the plurality of sub-boreholes are hydraulically fractured in sequence in the direction away from the bottom of the borehole 2, wherein after the hydraulic fracturing of one of the two adjacent sub-boreholes adjacent to the bottom of the borehole 2 is completed, the rock is cut from the inside of the one of the two adjacent sub-boreholes adjacent to the bottom of the borehole 2 to the outside so as to open a preventive cave, and then the one of the two adjacent sub-boreholes away from the bottom of the borehole 2 is hydraulically fractured. In other words, the borehole 2 is divided into multiple sections for hydraulic pressure, and after hydraulic fracturing of a section of the borehole 2 (each sub-borehole) in the direction away from the bottom of the borehole 2, a preventive cave is opened in the hydraulic fracture zone where the section of the borehole 2 (the sub-borehole) is located, and then the next section of the borehole 2 (the next sub-borehole) is hydraulically fractured. After each section of the borehole 2 (a sub-borehole) is hydraulically fractured, a preventive cave is opened in the newly formed hydraulic fracture zone, thereby reducing the difficulty of construction.

[0035] In step S1, the top rock layer above at least one of the tunnel to be treated and the working face to be mined, whose thickness is greater than or equal to the first preset value and whose compressive strength is greater than or equal to the second preset value, is divided into multiple layers of rock burst disaster-causing main controlling rock layer 1. In step S4, the top of the prevention and control cave is located at the top of the rock burst disaster-causing main controlling rock layer 1 where it is located, and the bottom of the prevention and control cave is located at the bottom of the rock burst disaster-causing main controlling rock layer 1 where it is located. In other words, the rock burst disaster-causing main controlling rock layer 1 can be multiple layers, and hydraulic fracturing is performed in each layer of the rock burst disaster-causing main controlling rock layer 1 and a prevention and control cave is opened, and the top of the prevention and control cave is adjacent to the top of the rock burst disaster-causing main controlling rock layer 1 where it is located, and the bottom of the prevention and control cave is adjacent to the bottom of the rock burst disaster-causing main controlling rock layer 1 where it is located, so as to increase the pressure relief effect.

[0036] The method for preventing and controlling rock burst according to an embodiment of the present invention also includes step S5. In step S5, after opening a plurality of prevention and control caves, the rock burst prevention and control effect is evaluated based on microseismic monitoring during the mining process. The rock burst prevention and control effect can be improved by increasing the number of boreholes 2, increasing the number of prevention and control caves, shortening the distance between two adjacent prevention and control caves, and increasing the hydraulic fracturing displacement. Specifically, based on microseismic monitoring during the mining process, the distribution and size of microseismic events of the breaking of the main controlling rock layer 1 causing rock burst disasters are analyzed, and compared with the working face where no measures are taken, the rock burst prevention and control effect is evaluated. The cave making and fracturing parameters are corrected according to the feedback of the prevention and control effect. The rock burst prevention and control effect can be improved by increasing the number of boreholes 2, increasing the number of prevention and control caves, shortening the distance between two adjacent prevention and control caves, and increasing the hydraulic fracturing displacement.

[0037] According to the method for preventing and controlling rock burst in the embodiment of the present invention, a drilling rig can be used to open a borehole 2 in the main rock formation 1 causing rock burst disasters at a long distance, and hydraulic fracturing is performed on the main rock formation 1 causing rock burst disasters, so as to relieve pressure and prevent impacts from the source of high stress. And by utilizing the combined effect of the prevention and control caves produced by hydraulic fracturing and hydraulic jet cavitation, the hard and complete main rock formation 1 causing rock burst disasters is transformed into a relatively broken top plate containing a large number of cavities. The transformed main rock formation 1 causing rock burst disasters is not prone to large-energy fracture events, reduces strong dynamic load disturbances, and can be used as a buffer layer to absorb the impact energy generated by other rock formations. The combined operation of hydraulic fracturing and hydraulic jet cavitation forms a complex hydraulic fracture network and large-area cavities in the main rock formation 1 causing rock burst disasters. It improves the degree of weakening of the hard rock layer 1 that causes rock burst disasters, expands the range of pressure relief, makes it easier to transfer high stress and release energy, avoids the adverse effects of local pressure relief measures on the stability of the tunnel surrounding rock, and effectively reduces the risk of rock burst at the working face. It improves the construction efficiency of anti-rock burst in the main rock layer area and reduces the cost of anti-rock burst construction.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; 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, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0043] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preventing and controlling rock burst, characterized in that: The following steps are involved: Step S1, classifying the roof rock layer above at least one of the tunnel to be treated and the working face to be mined, which has a thickness greater than or equal to a first preset value and a compressive strength greater than or equal to a second preset value, as the main rock layer causing rock burst disaster; Step S2, drilling a hole in the rock formation that controls the rock burst disaster; Step S3, hydraulically fracturing the main rock formation causing rock burst disaster by using the drill hole, so as to form a hydraulic fracture zone having hydraulic fractures in the main rock formation causing rock burst disaster; Step S4, opening a plurality of prevention and control caves connected to the hydraulic fracturing cracks in the hydraulic fracture area of ​​the main rock formation causing rock burst disaster.

2. The method for preventing and controlling rock burst according to claim 1, characterized in that: In the step S4, rock is cut outward from the borehole located in the hydraulic fracture zone to open a plurality of control caves.

3. The method for preventing and controlling rock burst according to claim 2, characterized in that: The control caves include a first control cave; In the step S4, a position in the borehole located in the hydraulic fracture zone is taken as the center position of the first control cave, and then the rock is cut outward to form the first control cave.

4. The method for preventing and controlling rock burst according to claim 3, characterized in that: In the step S4, a plurality of the first prevention and control caves are provided in the hydraulic fracture area and distributed along the extension direction of the borehole.

5. The method for preventing and controlling rock burst according to claim 4, characterized in that: In step S4, the distance between two adjacent first prevention and control caves in the extension direction of the same borehole is greater than or equal to 10 meters.

6. The method for preventing and controlling rock burst according to claim 2, characterized in that: After the hydraulic fracturing of the borehole is completed, the rock is cut outward from multiple positions in the borehole in sequence in a direction away from the bottom of the borehole so as to open a plurality of control caves.

7. The method for preventing and controlling rock burst according to claim 2, characterized in that: The borehole is divided into a plurality of sub-boreholes along the extension direction of the borehole, and the plurality of sub-boreholes are hydraulically fractured in sequence along the direction away from the bottom of the borehole, wherein after hydraulic fracturing is completed on one of the two adjacent sub-boreholes adjacent to the bottom of the borehole, rock is cut outward from the inside of one of the two adjacent sub-boreholes adjacent to the bottom of the borehole to open the control cave, and then hydraulic fracturing is performed on one of the two adjacent sub-boreholes away from the bottom of the borehole.

8. The method for preventing and controlling rock burst according to any one of claims 2 to 7, characterized in that: The diameter of the prevention and control cave is greater than or equal to 1 meter; In the step S2, there are multiple drill holes, and the multiple drill holes are arranged at intervals; In step S4, a hydraulic ejector is delivered to the borehole in the hydraulic fracture zone by a drilling rig, and the hydraulic ejector ejects jet water having a pressure greater than or equal to a third preset value to the rock in the hydraulic fracture zone so as to cut the rock.

9. The method for preventing and controlling rock burst according to claim 8, characterized in that: In the step S1, the top rock layer above at least one of the tunnel to be treated and the working face to be mined, whose thickness is greater than or equal to a first preset value and whose compressive strength is greater than or equal to a second preset value, is divided into multiple layers of the main rock layer causing rock burst disaster; In the step S2, the drill hole is opened upward from the formed tunnel, the horizontal extension direction of the drill hole and the extension direction of the tunnel to be treated are both in the first direction, a plurality of the drill holes are arranged at intervals in the second direction, and any two of the first direction, the second direction and the up-down direction are perpendicular to each other; In step S4, the top of the prevention and control cave is located at the top of the rock formation that controls rock burst disasters, and the bottom of the prevention and control cave is located at the bottom of the rock formation that controls rock burst disasters; In step S4, the pressure of the jet water is greater than or equal to 50 MPa.

10. The method for preventing and controlling rock burst according to claim 1, characterized in that: It also includes step S5. In step S5, after opening a plurality of the prevention and control caves, the working face to be mined is mined, and the rock burst prevention and control effect is evaluated based on microseismic monitoring during the mining process. The rock burst prevention and control effect can be improved by at least one of increasing the number of drill holes, increasing the number of the prevention and control caves, shortening the distance between two adjacent prevention and control caves, and increasing the hydraulic fracturing displacement.

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