CN117027802B - Method for preventing and controlling coal mine rock burst in advance in ground horizontal well segmented fracturing area - Google Patents
Method for preventing and controlling coal mine rock burst in advance in ground horizontal well segmented fracturing area Download PDFInfo
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Abstract
The invention belongs to the technical field of coal exploitation, and particularly relates to a method for preventing and controlling coal mine rock burst in advance in a sectional fracturing area of a ground horizontal well, which mainly comprises the following steps: impact tendency type division, regional anti-impact well position and well structure design, regional anti-impact fracturing design, anti-impact effect inspection and the like, and the hard top plate is caused to crack through segmented hydraulic fracturing, so that stress concentration phenomenon is eliminated, the top plate fracture energy is released, and the prevention and the control of the top plate impact disasters during coal seam exploitation are achieved.
Description
Technical Field
The invention belongs to the technical field of coal exploitation, and particularly relates to a method for preventing and controlling coal mine rock burst in advance in a sectional fracturing area of a ground horizontal well.
Background
The mining depth of coal mines in China increases at a speed of 8-16 meters per year, and the mining depth of many mines exceeds 1000 meters. As the production depth increases, the earth stress increases. When the coal seam roof is a stable thick lamellar hard roof, the hard roof cannot be broken and collapsed when the height of a caving belt is far smaller than the thickness of the hard roof during coal mining. Rock burst is easily caused as the goaf range is enlarged. The method for preventing and treating rock burst in the current common area comprises the following steps: and (3) pressure relief of large-diameter drilling, fracturing of hard rock stratum by a ground vertical well, blasting and presplitting of a top plate and the like.
The large-diameter drilling pressure relief method is characterized in that a hard top plate accumulating high compression energy is crushed and discharged through a construction drilling hole, so that a hard top plate structure is softened, and stratum stress concentration is eliminated, thereby achieving the purpose of pressure relief. However, the drilling pressure relief method has the problems of drill pressing, drill clamping and the like, and has limited single control range, and influences the construction safety and efficiency; the technology for fracturing the hard rock stratum of the ground vertical well is to pump fracturing fluid into the roof rock stratum through a hydraulic pump, so that artificial cracks with a certain geometric dimension are formed in a target layer, the strength of rock mass is weakened by large-area cracks, the integrity of the rock stratum and the breaking strength of the rock stratum are reduced, the elastic energy released by movement of the hard rock stratum is reduced, and a guarantee is provided for safe recovery of a working face of the hard roof. However, due to the influence of the stoping working face, the cracks of the low-level roof strata are relatively developed, micro cracks exist in the part of the high-level strata, and if the high-pressure liquid is communicated with the low-level strata along the weak face of the cracks, a large amount of high-pressure liquid is lost, so that the expected roof fracturing effect cannot be achieved. The roof blasting pre-cracking technology performs forced fracture through roof blasting measures, and a crushing area, a crushing belt and a crack area are formed in a roof stratum at the upper part of the coal pillar, so that on one hand, the peak stress intensity of the roof can be reduced, on the other hand, the stress is transferred to a deep non-crushing belt, the energy of the roof stratum is reduced, the stress is promoted to be released, and the danger of rock burst is reduced. However, the technology has the defects of high safety risk, high operation difficulty, easy induction of secondary disasters and the like.
Disclosure of Invention
Aiming at the problems of large area impact tendency of the existing hard roof of the coal mine, large drilling and pressure relief engineering quantity, incapability of advanced treatment and the like, a safe, efficient and advanced method for preventing and controlling the rock burst of the coal mine in an advanced area is needed to be designed, and important guarantee is provided for advanced prevention and control of the rock burst of the coal mine. In order to quickly and effectively prevent and treat the rock burst of the hard roof of the coal mine, the invention provides a method for preventing and treating the rock burst of the coal mine in advance in a sectional fracturing area of a ground horizontal well in order to quickly and effectively prevent and treat the rock burst of the hard roof of the coal mine under different conditions.
In order to achieve the above purpose, the invention adopts the following technical scheme:
A method for preventing and controlling coal mine rock burst in advance in a sectional fracturing area of a ground horizontal well comprises the following steps:
S1, geological survey is carried out, and the tensile strength, the bulk density and the elastic modulus of each layer of rock mass in the roof rock mass of the coal seam are respectively measured and recorded according to the distribution situation of the roof rock stratum in the overlying strata;
S2, impact tendency type division: based on the data measured in S1, the overburden load per unit width is calculated according to equation (1), which is as follows:
Wherein: q is the load of the overlying strata with unit width and MPa; e 1,E2...En is the elastic modulus of the overlying rock mass of layer1, the elastic modulus of the overlying rock mass of layer2. The elastic modulus of the overlying rock mass of layer n, MPa; h 1,h2...hn is the thickness of the overlying 1 st layer of rock mass, the thickness of the overlying 2 nd layer of rock mass; ρ 1,ρ2...ρn is the bulk density of the overburden 1 rock mass, the bulk density of the overburden 2 rock mass; g is gravity acceleration, N/kg; when the load of the n+1st layer to the 1 st layer is smaller than the load of the n layer to the 1 st layer, the calculation is terminated, and a calculation result of the n layer is taken; and then calculating the bending energy index of the single roof strata according to the unit width overburden stratum load and the formula (2):
Wherein: u WQ is the single roof bending energy index, kJ; r t is the tensile strength of the rock test piece and MPa; h is the thickness of a single top plate, m; e is the elastic modulus of the rock test piece and MPa; and then calculating the bending energy index of the composite roof according to the bending energy index of the single roof strata and the formula (3):
Wherein: u WQS is the bending energy index of the composite top plate, kJ; u WQi is the i-th layer bending energy index, kJ; n is the number of roof layers, and the thickness of the composite roof is taken to be 30m of the roof on the coal seam; after calculating the roof bending energy index, classifying the impact tendencies of roof strata, and the classification standard is shown in Table 1:
| Category(s) | Class I | Class II | Class III |
| Impact tendency | Without any means for | Weak and weak | Strong strength |
| Bending energy index/kJ | UWQS≤15 | 15＜UWQS≤120 | 120＜UWQS |
If the impact tendency is I, the control is not needed, if the impact tendency is II, the traditional control method is adopted, and if the impact tendency is III, the control is carried out by adopting the process of the invention;
S3, determining a rock burst prevention and control range and a target stratum layer: according to the early-stage coal field exploration hole data, combining coal mining thickness and coal seam roof lithology data, calculating the primary pressing step distance of a working face by using a plate model based on a mine pressure display theory, wherein the calculation formula is as follows:
Wherein: l C is the initial starting step distance of the top plate, m; k is the crack coefficient of the rock stratum, k=0.25-0.75, and dimensionless; σ t is the tensile strength of the roof strata, and MPa; h is the thickness of the roof strata, m; q is the load applied to the top plate and MPa; e i is the elastic modulus of the i-th layer of overlying rock mass and MPa; h i is the thickness of the i-th layer of overlying rock body, m; gamma i is the volume weight of the i-th layer of overlying rock mass, kN/m 3; the cycle step distance is calculated as follows:
Wherein: l z is the period step-by-step distance, m of the roof strata; h is the thickness of the roof strata, m; σ t is the tensile strength of the roof strata, and MPa; q is the load applied to the top plate and MPa; determining that the distance between two horizontal sections is not more than 220+L z according to the calculation result, wherein the length of the horizontal section of the horizontal well is 800 meters, selecting a hard top plate as a target layer, and carrying out well structure design on the basis, wherein one of the two sections is drilled to 10m below a stable bedrock, a J55 casing is drilled to 10m below the bedrock, and cement slurry is returned to the ground; beginning deflecting from the second drilling to 450m at the upper part of the target layer, drilling horizontally after drilling to the target layer by using a dog leg degree of 6 degrees/30 m until reaching the length of the designed horizontal section, and putting a P110 sleeve into the second drilling structure;
S4, area anti-impact fracturing design:
3) Fracturing material selection: according to logging stratum data, selecting a composite fracturing process of directional perforation and pumping bridge plug optical sleeve fracturing to perform staged fracturing operation, adopting deep penetration reinforcing bullets to perform perforation operation, wherein the effective depth of perforation is more than 800mm, selecting active water as fracturing construction liquid, and selecting quartz sand with 20-40 meshes as propping agent;
4) And (3) designing a fracturing point and a scale: when the staged fracturing is carried out, the cluster spacing is not more than 100+L z, the perforation is carried out by taking the half-period starting step spacing as the spacing, the perforation length is 1m, and the perforation direction is the directional two-wing perforation;
S5, guiding ground drilling and segmented fracturing according to the steps;
S6, carrying out hydraulic fracturing real-time monitoring on the roof strata of the coal seam by adopting a fracturing well microseism crack monitoring and evaluating system in the fracturing process until the fracturing construction is finished, and checking the anti-impact effect according to the hydraulic fracturing monitoring result.
Further, during staged fracturing, high-pressure fracturing fluid is pumped into a to-be-fractured stage through a ground fracturing truck and is continuously pressurized, staged fracturing is achieved by adopting a pumping bridge plug, the fracturing construction displacement is 14m 3/min, and the fracturing construction fluid quantity is 1000m 3.
Furthermore, the fracture well microseism crack monitoring and evaluating system comprises a crack real-time monitoring system, a microseism detector, a signal amplifier, a wireless transmitting and transmitting receiver, a high-precision GPS and a PC computer.
Further, the specific operation of checking the impact protection effect comprises the following steps:
1) Monitoring on-site investigation: recording coordinates, topography and topography of an anti-scour wellhead;
2) Arranging monitoring substations, recording coordinates of each substation, and solving the position of each substation relative to the anti-flushing well;
3) Setting and debugging system parameters: opening a main substation instrument, debugging communication and data transmission between main substations, and setting parameters;
4) And starting the fracturing construction of the target layer, opening a microcrack monitoring system to enter a monitoring state, and at the moment, automatically collecting, recording waveforms, processing data and displaying the state of the microseismic waves in real time by the system. The fracturing construction of the target layer is finished, and the data is stored and shut down;
5) And (5) collecting all the monitoring devices to complete the field monitoring.
The invention has the advantages that:
1. The invention designs a method for preventing and controlling the rock burst of a hard roof of a coal mine by staged fracturing of a ground horizontal well, which causes the hard roof to crack by staged hydraulic fracturing, eliminates stress concentration phenomenon, releases the fracture energy of the roof and achieves the prevention and control of roof impact disasters during coal mining;
2. According to the division of the impact tendency of the top plate, the multi-layer hard rock stratum of the coal seam overlying strata is subjected to pressure relief through the sectional fracturing of the ground horizontal well, and compared with the traditional rock burst prevention and control measures, the method has the advantages of low engineering geological condition limitation, wide control range, good pressure relief effect and safe and efficient implementation of the purpose of rock burst advanced prevention and control.
Drawings
FIG. 1 is a process flow diagram of the present invention.
FIG. 2 is a schematic illustration of a wellbore configuration and wellbore trajectory in an embodiment.
Fig. 3 is a fracture point plane projection profile.
Fig. 4 is a graph of proppant fracture simulation results for different scales.
Fig. 5 is a graph of different displacement hydraulic fracture simulation results.
FIG. 6 shows hydraulic fracturing simulation results for different amounts of construction fluid.
Fig. 7 is a graph of fracture monitoring outcome.
Figure 8 is a schematic of a well surface tubing connection.
Detailed Description
The method for preventing and controlling the rock burst of the coal mine in advance in the sectional hydraulic fracturing area of the ground horizontal well mainly comprises the following steps: impact tendency type division, regional anti-impact well position and well body structural design, regional anti-impact fracturing design, anti-impact effect inspection and the like. The technological process for advanced prevention and control of coal mine rock burst in the horizontal well segmented fracturing area is shown in figure 1.
(1) Impact predisposition type classification
According to the prior prospecting hole data of the coal field, and by combining the measuring method of the physical and mechanical properties of coal and rock (GB/T23561-2009), the physical parameters such as the tensile strength, the bulk density, the elastic modulus and the like of the coal seam roof rock mass are tested. Classifying the impact tendencies of the roof strata according to the roof strata bending energy index, and calculating the impact tendencies of the roof strata according to the following steps:
Wherein: q is the load of the overlying strata with unit width and MPa; e 1,E2...En is the elastic modulus of the overlying rock mass of layer 1, the elastic modulus of the overlying rock mass of layer 2. The elastic modulus of the overlying rock mass of layer n, MPa; h 1,h2...hn is the thickness of the overlying 1 st layer of rock mass, the thickness of the overlying 2 nd layer of rock mass; ρ 1,ρ2...ρn is the bulk density of the overburden 1 rock mass, the bulk density of the overburden 2 rock mass; g is gravity acceleration, N/kg.
When the load of the n+1 layer to the 1 st layer is smaller than the load of the n layer to the 1 st layer, the calculation is terminated, and the calculation result of the n layer is taken.
The single roof bending energy index calculation method comprises the following steps:
Wherein: u WQ is the single roof bending energy index, kJ; r t is the tensile strength of the rock test piece and MPa; h is the thickness of a single top plate, m; e is the elastic modulus of the rock test piece and MPa.
The method for calculating the bending energy index of the composite top plate comprises the following steps:
Wherein: u WQS is the bending energy index of the composite top plate, kJ; u WQi is the i-th layer bending energy index, kJ; n is the number of roof layers, and the thickness of the composite roof is generally taken to be 30m of the roof on the coal seam.
After the roof bending energy index is calculated, the roof strata impact tendencies are classified, and the classification criteria are shown in table 1.
Table 1 classification and index of impact tendencies of roof strata
| Category(s) | Class I | Class II | Class III |
| Impact tendency | Without any means for | Weak and weak | Strong strength |
| Bending energy index/kJ | UWQS≤15 | 15＜UWQS≤120 | 120＜UWQS |
If the impact tendency is I, the control is not needed, if the impact tendency is II, the traditional control method is adopted, and if the impact tendency is III, the control is carried out by adopting the process of the invention;
(2) Regional anti-flushing well site and well body structural design
According to the early-stage coal field exploration hole data, combining coal mining thickness and coal seam roof lithology data, calculating the primary and periodic step-by-step distance of a working surface by using a plate model based on a mine pressure display theory, wherein the calculation formula is as follows:
Wherein: l C is the initial starting step distance of the top plate, m; k is the crack coefficient of the rock stratum, k=0.25-0.75, and dimensionless; σ t is the tensile strength of the roof strata, and MPa; h is the thickness of the roof strata, m; q is the load applied to the top plate and MPa; e i is the elastic modulus of the i-th layer of overlying rock mass and MPa; h i is the thickness of the i-th layer of overlying rock body, m; gamma i is the volume weight of the i-th layer of overlying rock mass, kN/m 3.
Wherein: l z is the period step-by-step distance, m of the roof strata; h is the thickness of the roof strata, m; σ t is the tensile strength of the roof strata, and MPa; q is the load applied to the top plate and MPa.
In general, the long axis of the hydraulic fracture plastic ring influence range is 110-130 m, in order to ensure the rock burst prevention effect, the dead zone of the two horizontal section fracture influence range does not exceed one period to press the step distance, therefore, the distance between the two horizontal sections is not more than 220+L z, the length of the horizontal section of the horizontal well is 800 m, and the rock burst prevention effect of a complete mining working surface can be ensured after the single horizontal section is reformed. Carrying out well structure design on the basis, wherein the well is drilled to 10m below a stable bedrock, the J55 casing is drilled to 10m below the bedrock, and cement slurry is returned to the ground; and (3) starting deflecting from the second drilling to the 450m position on the upper part of the target layer, drilling horizontally after drilling to the target layer by using the dogleg degree of 6 degrees/30 m until reaching the designed horizontal section length, and putting the P110 sleeve into the second drilling structure.
Taking the thickness of bedrock of a certain coal seam as 40m, the burial depth of a target coal seam roof as 600m and the thickness of the roof as 30m as an example, the well body structural design is shown in table 2 and figure 2.
TABLE 2 rock burst control horizontal well bore structure data
(3) Area anti-impact fracturing design
1) Fracturing material selection
According to logging stratum data, a composite fracturing process of directional perforation and pumping bridge plug optical sleeve fracturing is selected for staged fracturing operation, deep penetration reinforcing bullets are adopted for perforation operation, the effective depth of perforation is more than 800mm, active water (clear water+1.0% potassium chloride) is selected as fracturing construction liquid, and pollution of the liquid to stratum is reduced; quartz sand of 20/40 mesh is selected as a propping agent.
2) Fracturing point and scale design
In general, the short axis of the plastic ring of the hydraulic fracture is 60-80 m, in order to ensure the control effect of rock burst, the cluster spacing during staged fracturing is not more than 100+L z, the step spacing is pressed according to the period, the perforation is carried out by taking the step spacing as the interval of the half period, the perforation length is 1m, and the perforation direction is the directional two-wing perforation, as shown in figure 3.
The fracture simulation was performed using fracture simulation software to simulate a 20/40 mesh proppant of 35m 3 and a 20/40 mesh proppant of 45m 3, and the simulation results showed that the fracture length and the height were slightly different, as shown in table 3 and fig. 4. In order to avoid sand blockage, a 35m 3 -scale propping agent is selected, and the scale is increased appropriately according to the on-site fracturing condition.
Table 3 table of a list of horizontal well fracture geometry for different fracturing scales
And simulating the extension length and the height of cracks under different displacement and liquid quantity by adopting fracturing simulation software, and optimizing the pumping displacement and the liquid quantity on the basis.
Taking a hard rock formation with a thickness of 100 meters as an example, a fracturing simulation was performed, as shown in fig. 5.
In order to ensure the rock burst treatment effect, the length of the seam is ensured, the height of the seam is ensured, the change characteristics of the crack form (seam length and seam height) and the flow conductivity during the fracturing construction are analyzed through the simulation result, and the optimal fracturing construction discharge capacity is about 14m 3/min from the economic aspect.
The fracturing cracks are simulated under different construction liquid amounts, the construction displacement is 14m 3/min, the liquid amounts are 800m 3、1000m3、1200m3、1400m3 respectively, and the distribution ratio of the front fluid and the sand carrying fluid is kept unchanged, so that the simulation result is shown in figure 6.
When the fracturing construction displacement is 14m 3/min, the strongest flow conductivity of the liquid can be obtained when the liquid is 800m 3 by changing the liquid amount to analyze the change characteristics of the fracture morphology (the fracture length and the fracture height) and the flow conductivity; the larger the liquid amount, the longer the crack length and the longer the supporting crack length. Therefore, the optimal fracturing construction liquid amount is 1000m 3 when the joint length, the joint height and the flow conductivity are combined and the discharge capacity is 14m 3/min.
When specifically drilling and fracturing, the drilling ground pipeline in fig. 8 is used for connection, the drilling device comprises a drilling machine 1, a drill rod 2 connected with the drilling machine, a drill collar 8 and a drill bit 9 are arranged at the end part of the drill rod, the drill collar is positioned below a wellhead, a wellhead device 3 is arranged on the wellhead, an auxiliary device 7 is arranged at the edge of the wellhead, a fracturing pipeline 5 is arranged in the wellhead, a control valve 4 is arranged on the fracturing pipeline, an outlet of the fracturing pipeline is connected with a fracturing pump truck 10, the fracturing pump truck is connected with a fracturing tank truck 11 through a pipeline, the drilling device further comprises an instrument control truck 12, a covering layer 13 is covered on the surface of a base rock layer 14, and a roof rock layer 15 and a coal layer 16 are sequentially arranged at the bottom of the base rock layer.
(4) Anti-impact effect test
The method comprises the following steps that during fracturing construction, the fracturing end points of each fracturing layer section are calculated according to fracturing design, the projection of the fracturing end points on the ground is taken as the center, detectors are arranged according to the surrounding topography and landform (taking the center of the horizontal well section as the center), the detectors are positioned accurately by using the high-precision GPS, the embedding depth is not less than 0.2m, and the on-site monitoring system and the computer and the corresponding expert interpretation system are used for interpreting and analyzing on-site monitoring real-time data, wherein the method comprises the following steps:
1) Monitoring on-site investigation: recording coordinates, topography and topography of an anti-scour wellhead;
2) Arranging monitoring substations, recording coordinates of each substation, and solving the position of each substation relative to the anti-flushing well;
3) Setting and debugging system parameters: and opening the instrument of the main substation, debugging communication and data transmission between the main substation and the substation, and setting parameters.
4) And starting the fracturing construction of the target layer, opening a microcrack monitoring system to enter a monitoring state, and at the moment, automatically collecting, recording waveforms, processing data and displaying the state of the microseismic waves in real time by the system. And (5) finishing the fracturing construction of the target layer, and storing the data and shutting down.
5) And (5) collecting all the monitoring devices to complete the field monitoring.
The results of the fracture monitoring are shown in figure 7.
Table 4 the inventive process is compared with the conventional rock burst control process, see table
Claims (4)
1. The method for preventing and controlling the rock burst of the coal mine in advance in the sectional fracturing area of the ground horizontal well is characterized by comprising the following steps of:
S1, geological survey is carried out, and the tensile strength, the bulk density and the elastic modulus of each layer of rock mass in the roof rock mass of the coal seam are respectively measured and recorded according to the distribution situation of the roof rock stratum in the overlying strata;
S2, impact tendency type division: based on the data measured in S1, the overburden load per unit width is calculated according to equation (1), which is as follows:
Wherein: q is the load of the overlying strata with unit width and MPa; e 1,E2...En is the elastic modulus of the overlying rock mass of layer1, the elastic modulus of the overlying rock mass of layer2. The elastic modulus of the overlying rock mass of layer n, MPa; h 1,h2...hn is the thickness of the overlying 1 st layer of rock mass, the thickness of the overlying 2 nd layer of rock mass; ρ 1,ρ2...ρn is the bulk density of the overburden 1 rock mass, the bulk density of the overburden 2 rock mass; g is gravity acceleration, N/kg; when the load of the n+1st layer to the 1 st layer is smaller than the load of the n layer to the 1 st layer, the calculation is terminated, and a calculation result of the n layer is taken; and then calculating the bending energy index of the single roof strata according to the unit width overburden stratum load and the formula (2):
Wherein: u WQ is the single roof formation bending energy index, kJ; r t is the tensile strength of the rock test piece and MPa; h is the thickness of a single top plate, m; e is the elastic modulus of the rock test piece and MPa; and then calculating the bending energy index of the composite roof according to the bending energy index of the single roof strata and the formula (3):
Wherein: u WQS is the bending energy index of the composite top plate, kJ; u WQi is the i-th layer bending energy index, kJ; n is the number of roof layers, and the thickness of the composite roof is taken to be 30m of the roof on the coal seam; after calculating the bending energy index of the composite roof, classifying the impact tendencies of roof strata, and classifying the impact tendencies of roof strata, wherein the classification standard is shown in Table 1:
TABLE 1
S3, determining a rock burst prevention and control range and a target stratum layer: when the impact tendency is class III, according to the early-stage coal field exploration hole data, combining coal mining thickness and coal seam roof lithology data, calculating the primary compaction step distance of a working surface by using a plate model based on a mine pressure display theory, wherein the calculation formula is as follows:
Wherein: l C is the initial starting step distance of the top plate, m; k is the crack coefficient of the rock stratum, k=0.25-0.75, and dimensionless; σ t is the tensile strength of the roof strata, and MPa; h is the thickness of the roof strata, m; q is the load applied to the top plate and MPa; e i is the elastic modulus of the i-th layer of overlying rock mass and MPa; h i is the thickness of the i-th layer of overlying rock body, m; gamma i is the volume weight of the i-th layer of overlying rock mass, kN/m 3; the cycle step distance is calculated as follows:
Wherein: l z is the period step-by-step distance, m of the roof strata; h is the thickness of the roof strata, m; σ t is the tensile strength of the roof strata, and MPa; q is the load applied to the top plate and MPa; determining that the distance between two horizontal sections is not more than 220+L z according to the calculation result, wherein the length of the horizontal section of the horizontal well is 800 meters, selecting a hard top plate as a target layer, and carrying out well structure design on the basis, wherein one of the two sections is drilled to 10m below a stable bedrock, a J55 casing is drilled to 10m below the bedrock, and cement slurry is returned to the ground; beginning deflecting from the second drilling to 450m at the upper part of the target layer, drilling horizontally after drilling to the target layer by using a dog leg degree of 6 degrees/30 m until reaching the length of the designed horizontal section, and putting a P110 sleeve into the second drilling structure;
S4, area anti-impact fracturing design:
1) Fracturing material selection: according to logging stratum data, selecting a composite fracturing process of directional perforation and pumping bridge plug optical sleeve fracturing to perform staged fracturing operation, adopting deep penetration reinforcing bullets to perform perforation operation, wherein the effective depth of perforation is more than 800mm, selecting active water as fracturing construction liquid, and selecting quartz sand with 20-40 meshes as propping agent;
2) And (3) designing a fracturing point and a scale: when the staged fracturing is carried out, the cluster spacing is not more than 100+L z, the perforation is carried out by taking the half-period starting step spacing as the spacing, the perforation length is 1m, and the perforation direction is the directional two-wing perforation;
S5, guiding ground drilling and segmented fracturing according to the steps;
S6, carrying out hydraulic fracturing real-time monitoring on the roof strata of the coal seam by adopting a fracturing well microseism crack monitoring and evaluating system in the fracturing process until the fracturing construction is finished, and checking the anti-impact effect according to the hydraulic fracturing monitoring result.
2. The method for advanced prevention and treatment of coal mine rock burst in a ground horizontal well section fracturing area according to claim 1, wherein the method comprises the following steps: during staged fracturing, high-pressure fracturing fluid is pumped into a to-be-fractured stage through a ground fracturing truck and is continuously pressurized, staged fracturing is achieved by adopting a pumping bridge plug, the fracturing construction displacement is 14m 3/min, and the fracturing construction fluid quantity is 1000m 3.
3. The method for advanced prevention and treatment of coal mine rock burst in a ground horizontal well section fracturing area according to claim 2, wherein the method comprises the following steps: the fracture well microseism crack monitoring and evaluating system comprises a crack real-time monitoring system, wherein the crack real-time monitoring system comprises a microseism detector, a signal amplifier, a wireless transmitting and transmitting receiver, a high-precision GPS and a PC computer.
4. A method for advanced control of coal mine rock burst in a ground horizontal well section fracture zone as claimed in claim 3, wherein the specific operation of checking the impact protection effect comprises:
1) Monitoring on-site investigation: recording coordinates, topography and topography of an anti-scour wellhead;
2) Arranging monitoring substations, recording coordinates of each substation, and solving the position of each substation relative to the anti-flushing well;
3) Setting and debugging system parameters: opening a main substation instrument, debugging communication and data transmission between main substations, and setting parameters;
4) Starting the fracturing construction of the target layer, opening a fracture real-time monitoring system to enter a monitoring state, automatically collecting micro shock waves, recording waveforms, processing data and displaying the state in real time by the system, ending the fracturing construction of the target layer, storing the data and shutting down the device;
5) And (5) packing up the microseismic detector to complete the field monitoring.
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| CN111005722A (en) * | 2018-12-12 | 2020-04-14 | 天地科技股份有限公司 | Well arrangement method for governing rock burst at pressure relief source of ground fracturing area |
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| CN111859712A (en) * | 2020-08-03 | 2020-10-30 | 重庆大学 | Ground advanced pre-control method for coal mine rock burst |
| CN113404535A (en) * | 2021-07-07 | 2021-09-17 | 陕西彬长孟村矿业有限公司 | Method for preventing rock burst by hydraulic fracturing of coal mine underground |
| CN115788435A (en) * | 2022-11-30 | 2023-03-14 | 陕西彬长孟村矿业有限公司 | System and method for preventing rock burst in coal mine from up and down in three-dimensional manner |
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| CN111005722A (en) * | 2018-12-12 | 2020-04-14 | 天地科技股份有限公司 | Well arrangement method for governing rock burst at pressure relief source of ground fracturing area |
| CN111520184A (en) * | 2020-05-29 | 2020-08-11 | 陕西省煤层气开发利用有限公司 | Comprehensive control system and method for coal mine rock burst and harmful gas |
| CN111859712A (en) * | 2020-08-03 | 2020-10-30 | 重庆大学 | Ground advanced pre-control method for coal mine rock burst |
| CN113404535A (en) * | 2021-07-07 | 2021-09-17 | 陕西彬长孟村矿业有限公司 | Method for preventing rock burst by hydraulic fracturing of coal mine underground |
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