A method and device for simulating rock burst by carbon dioxide fracturing tube blasting
Through the carbon dioxide fracturing tube blasting method and numerical simulation, a mapping relationship between particle parameters and rockburst energy level was constructed, which solved the accuracy problem of existing rockburst simulation methods and achieved efficient and safe rockburst simulation.
Patent Information
- Application Number
- CN202510872872.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-27
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2045-06-27
AI Technical Summary
Existing rockburst simulation methods are unable to accurately simulate the rockburst process, especially under high ground stress conditions, which makes it difficult to construct components of the rockburst protection system and test their bearing performance.
The carbon dioxide fracturing tube blasting method is used to obtain the particle microscopic parameters of rock specimens, conduct blasting tests and numerical simulations, establish a mapping relationship between particle parameters and blasting parameters, simulate rockburst characteristics at different energy levels, reduce the number of physical tests and improve simulation accuracy.
It has achieved accurate simulation of rockburst and rock ejection phenomena under laboratory conditions, reduced safety risks and costs, and improved the accuracy and efficiency of rockburst simulation.
Smart Images
Figure CN120405092B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of computer technology, and in particular to a method and device for simulating rock burst by blasting a carbon dioxide fracturing tube. Background Art
[0002] During railway tunnel construction, the stability of tunnel excavation is often affected by the complex geological environment. Under high geostress conditions, brittle hard rock can experience dynamic instability after unloading during excavation, known as rockburst. This phenomenon severely impacts tunnel construction safety and poses a significant risk to life and property. Testing can often be used to determine the threat posed by rockburst to protective systems, allowing for targeted mitigation measures.
[0003] Existing testing methods fall into two main categories. One involves using on-site drop ball tests to equate rockburst energy. This approach is reliable for demonstrating the load-bearing performance of protection systems. However, the regular shape of the drop ball differs from that of actual rockburst fragments, weakening the shearing effect of sharp rock surfaces. Furthermore, the falling process of the drop ball under gravity differs from the sudden impact of rockburst fragments. The second approach involves recreating the rockburst process through true triaxial model testing. This method inevitably requires scaling down the tunnel to perform the test model in order to achieve the desired in-situ stress.
[0004] In summary, the existing rockburst simulation methods cannot accurately simulate the rockburst process in the field. Summary of the Invention
[0005] Based on this, it is necessary to provide a method and device for simulating rock burst by blasting a carbon dioxide fracturing tube to address the above technical problems.
[0006] The present invention adopts the following technical solutions:
[0007] The present invention provides a method for simulating rock burst through carbon dioxide fracturing tube blasting. The method comprises the following steps: first, obtaining particle microscopic parameters reflecting the physical properties of a rock specimen; then conducting a carbon dioxide fracturing tube blasting test on the rock specimen; and determining the distribution pattern of explosive blocks during the blasting process. Then, the carbon dioxide fracturing tube blasting is numerically simulated multiple times to correct the particle microscopic parameters. At the same time, a first mapping relationship between simulation parameters of explosion point particles and carbon dioxide fracturing tube parameters in the numerical simulation is constructed. Finally, the carbon dioxide fracturing tube blasting under different blasting conditions is simulated through numerical simulation to match real rock burst characteristics at different energy levels. A second mapping relationship between simulation parameters of explosion point particles and rock burst energy levels is constructed. Based on the first mapping relationship and the second mapping relationship, a mapping relationship between the carbon dioxide fracturing tube parameters and rock bursts at different energy levels is determined, thereby simulating rock burst through carbon dioxide fracturing tube blasting in practice.
[0008] The present invention provides a device for simulating rock burst by blasting a carbon dioxide fracturing tube, comprising:
[0009] Rock modeling module, used to obtain particle microscopic parameters reflecting the physical properties of rock specimens;
[0010] The blasting test module is used to conduct carbon dioxide fracturing tube blasting tests on rock specimens and determine the distribution pattern of explosive blocks during the blasting process;
[0011] The blasting simulation module is used to use the discrete element method to equate the carbon dioxide fracturing tube to the explosion point particle, simulate the carbon dioxide fracturing tube blasting multiple times to correct the particle microscopic parameters until the distribution pattern of the explosion block is restored; and determine the first mapping relationship between the simulation parameters of the explosion point particle and the carbon dioxide fracturing tube parameters;
[0012] The matching module is used to simulate the blasting process under different blasting conditions based on the modified particle microscopic parameters and the explosion point particles with different simulation parameters using the discrete element method, and to match the real rockburst characteristics at different energy levels, thereby constructing a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level;
[0013] The rock burst simulation mapping module is used to determine the mapping relationship between the carbon dioxide fracturing tube parameters and rock bursts of different energy levels according to the first mapping relationship and the second mapping relationship, so as to simulate rock bursts by blasting the carbon dioxide fracturing tube in the field.
[0014] The present invention provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the method for simulating rock burst by blasting with carbon dioxide-induced fracturing tubes is implemented.
[0015] The present invention provides a computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for simulating rock burst by blasting a carbon dioxide fracturing tube is implemented.
[0016] At least one of the above technical solutions adopted by the present invention can achieve the following beneficial effects:
[0017] The impact process of carbon dioxide fracturing tube blasting is quite similar to that of the explosive blocks after rockburst. However, exploring how to accurately simulate rockburst through physical experiments with carbon dioxide fracturing tube blasting has safety risks and is costly.
[0018] The present invention takes a single carbon dioxide fracturing tube blasting test as a benchmark, adopts a particle flow discrete element modeling method to accurately simulate the carbon dioxide fracturing tube blasting test, corrects the particle micro-parameters reflecting the physical properties of the rock specimen through multiple simulations, and simultaneously determines the mapping relationship between the simulation parameters of the explosive point particles and the carbon dioxide fracturing tube parameters. Then, based on the corrected particle micro-parameters, the blasting process under different blasting conditions is simulated to match the real rockburst characteristics of different energy levels. The mapping relationship between the carbon dioxide fracturing tube blasting and the rockburst is accurately connected through the numerical simulation process, thereby obtaining an accurate mapping relationship between the carbon dioxide fracturing tube parameters and rockbursts of different energy levels, so that carbon dioxide fracturing tube blasting can be carried out in the field to accurately simulate rockbursts of the target energy level.
[0019] The present invention restores the actual rockburst and rock ejection phenomenon at the laboratory scale through physical blasting tests and numerical simulations of carbon dioxide fracturing tubes. Through fewer physical tests, the mapping relationship between carbon dioxide fracturing tube parameters and rockbursts of different energy levels is determined for application in field rockburst simulations, thereby improving the accuracy of field rockburst simulations. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:
[0021] Figure 1 A schematic flow chart of a method for simulating rock burst by carbon dioxide fracturing tube blasting provided by the present invention;
[0022] Figure 2 A schematic diagram of discrete element modeling of a rock sample provided by the present invention;
[0023] Figure 3 A schematic diagram of a carbon dioxide fracturing tube explosion test provided by the present invention;
[0024] Figure 4 A schematic diagram of numerical simulation of carbon dioxide fracturing tube explosion provided by the present invention;
[0025] Figure 5 A schematic diagram of a blasting stress wave provided by the present invention;
[0026] Figure 6 A schematic diagram of the ejection phenomenon of explosive pieces during the blasting of a carbon dioxide fracturing tube provided by the present invention;
[0027] Figure 7 A schematic diagram of a device for simulating rock burst by blasting a carbon dioxide fracturing tube provided by the present invention. DETAILED DESCRIPTION
[0028] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0029] At present, the equivalent rockburst energy obtained through on-site drop ball tests is quite different from the actual rockburst blocks. Testing through models will make it difficult to construct rockburst protection system components (anchor rods, protective nets, etc.) on the models, and it is impossible to test the bearing capacity of the rockburst protection system.
[0030] In order to verify the threat level of rockburst rocks to the protection system in the laboratory, the idea of the present invention is to use carbon dioxide fracturing tubes to apply impact loads to the rocks to restore the rockburst rock throwing phenomenon. However, since this field is still blank, there is no clear mapping relationship between the amount and installation position of carbon dioxide fracturing tubes and the kinetic energy of rocks under different rockburst energy levels. In addition, exploring the mapping relationship between the two through multi-condition physical blasting tests will bring about problems such as increased test costs, high safety risks and large manpower investment.
[0031] The technical solutions provided by various embodiments of the present invention are described in detail below with reference to the accompanying drawings.
[0032] Figure 1 The present invention provides a method for simulating rock burst by blasting a carbon dioxide fracturing tube, which specifically includes the following steps:
[0033] S101: Obtaining particle microscopic parameters reflecting the physical properties of the rock specimen.
[0034] S102: Conduct a carbon dioxide fracturing tube blasting test on the rock specimen and determine the distribution pattern of the explosive blocks during the blasting process.
[0035] S103: Using the discrete element method, the carbon dioxide fracturing tube is equivalent to the explosion point particle, and the carbon dioxide fracturing tube blasting is simulated multiple times to correct the particle microscopic parameters until the distribution pattern of the explosion block is restored; and a first mapping relationship between the simulation parameters of the explosion point particle and the carbon dioxide fracturing tube parameters is determined.
[0036] S104: Using the discrete element method, based on the corrected particle microscopic parameters and the explosion point particles with different simulation parameters, the blasting process under different blasting conditions is simulated, and the real rockburst characteristics at different energy levels are matched, thereby constructing a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level.
[0037] S105: Determine a mapping relationship between the carbon dioxide fracturing tube parameters and rock bursts of different energy levels based on the first mapping relationship and the second mapping relationship, so as to simulate rock bursts by blasting the carbon dioxide fracturing tube in situ.
[0038] Generally, when there are risks in physical experiments, it is possible to consider performing a certain degree of simulation through numerical simulation to reduce the number of actual physical experiments. Among them, how to perform numerical simulation is related to whether the numerical simulation can accurately reflect the physical test conditions.
[0039] Based on this, in one or more embodiments of the present invention, particle flow discrete element modeling is used to numerically simulate the rock in the construction area. Particle flow is a discrete element method that simulates the macroscopic mechanical properties of materials through the interactions between circular particles. Because the macroscopic physical and mechanical parameters corresponding to the numerical model and the microscopic parameters of the particles are generally not one-to-one corresponding during discrete element numerical simulation, the present invention can first conduct uniaxial compression tests and Brazilian splitting tests on rock samples, respectively, to obtain pressure stress-strain curves and tensile stress-strain curves of the rock samples as actual test results. Then, particle flow is used to perform isometric discrete element modeling on the rock samples, and initial mesoscopic parameters are assigned to each particle to obtain an initial rock simulation sample. Next, the pressure stress-strain curves and tensile stress-strain curves corresponding to the numerical simulation test results of the initial rock simulation sample are determined. Based on the deviation between the numerical simulation test results of the rock simulation sample and the actual test results of the rock sample, the initial mesoscopic parameters are corrected. Finally, through multiple rounds of iterative correction, the numerical simulation test results are aligned with the actual test results, resulting in multiple sets of initial particle mesoscopic parameters reflecting the physical properties of the rock sample.
[0040] Since each set of initial particle mesoscopic parameters includes multiple mesoscopic parameters, multiple sets of initial particle mesoscopic parameters are different combinations of multiple mesoscopic parameters, and each combination may meet the purpose of matching the numerical simulation test results with the actual test results, then each set of initial particle mesoscopic parameters can be retained, and subsequently the multiple sets of initial particle mesoscopic parameters can be screened through the blasting simulation process to obtain the best final particle mesoscopic parameters.
[0041] For example, rock samples corresponding to the rock specimens can be obtained first, and samples for uniaxial compression tests and Brazilian splitting tests can be taken separately, wherein the diameter of the uniaxial compression specimen can be 50 mm and the height can be 100 mm, and the diameter of the Brazilian splitting specimen can be 50 mm and the height can be 25 mm.
[0042] By performing uniaxial compression tests and Brazilian splitting tests on rock samples, their pressure stress-strain curves and tensile stress-strain curves can be obtained. Then, the particle flow discrete element modeling can be performed. The rock sample is composed of round particles, and appropriate particle microscopic parameters are assigned to the contact between particles. The wall unit applies loads, such as Figure 2 As shown, Figure 2 This is a schematic diagram of discrete element modeling of a rock sample in the present invention. Figure 2 The left side of the center shows a schematic diagram of a uniaxial compression test on a rock sample, and the right side shows a schematic diagram of a Brazilian splitting test on a rock sample. For the calibration of particle microscopic parameters, a "trial and error" method can be used to calibrate various parameters of the rock sample.
[0043] For example, first, the stiffness ratio (kratio) and internal friction angle are kept unchanged, and the macroscopic compressive elastic modulus is controlled by adjusting the particle contact modulus (emod) and parallel bond modulus (pb_emod). Secondly, the Poisson's ratio is controlled by the stiffness ratio. For the change of the elastic modulus in this process, repeated iterations are used to achieve a reasonable elastic modulus and Poisson's ratio. Finally, the internal friction angle and cohesion of the rock can be controlled by adjusting the parallel bond normal strength (pb_ten) and tangential strength (pb_coh), so that its pressure stress-strain curve and tensile stress-strain curve are as consistent as possible with the actual experimental curve. Finally, by restoring the rock sample indoor test, the uniaxial compression and Brazilian splitting numerical simulation are completed, and multiple sets of initial particle micro-parameters that can better reflect the physical properties of the rock are obtained.
[0044] Afterwards, a CO2 fracturing tube blasting test can be conducted based on a rock specimen of a predetermined size that has the same physical properties as the rock sample.
[0045] For example, a rock specimen with an overall size of 1.2m×1.2m×1.2m can be prefabricated, and a circular hole with a diameter of 60mm and a depth of 800mm can be prefabricated on the rock specimen to facilitate the installation of the carbon dioxide fracturing pipe. Figure 3 As shown, Figure 3 This is a schematic diagram of a carbon dioxide fracturing tube explosion test in the present invention. Figure 3 The left side of the middle diagram is a schematic diagram of the rock specimen being blasted by a fracturing tube, and the right side (a) to (d) are schematic diagrams of the process of the rock specimen being blasted by a fracturing tube.
[0046] After the rock specimens are processed, they can be moved to the blasting site. When prefabricating the rock specimens, each CO2 fracturing tube is filled with 0.7L of liquid CO2. Once sealed, the tubes are carried to the blasting site. A 1.2m x 1.2m x 1.2m rock specimen is tested. With the prefabricated circular hole facing upwards, the tube vent is located at the bottom of the hole. The tubes are placed in the prefabricated holes in the rock specimens and sealed with quick-drying cement to prevent them from flying. After installing the tubes, personnel retreat to a safe distance and detonate them for a fully free-face blasting test.
[0047] In one or more embodiments of the present invention, a high-speed camera can be used to record the blasting process. Using the camera's motion capture function, the explosive fragments can be captured to produce images of their ejection. Subsequently, the images of the explosive fragments captured during the blasting process can be used to determine the ejection velocity of each fragment. The velocity distribution of each fragment can then be determined based on its size and distance from the target location.
[0048] For the distribution law of blasting blocks, the fractal dimension can be calculated based on the blasting blocks after the rock specimens are broken. The blasting blocks can be divided into multiple levels according to the fragmentation size. For example, the side lengths of the blasting blocks can be sieved according to 0.5m, 0.25m, 0.1m, 0.05m, 0.02m, 0.01m and 0.005m. The mass of the blasting blocks corresponding to each level of fragmentation size can be determined by a high-precision balance. In order to quantify the distribution characteristics of the fragmentation size at each level, the fragmentation size distribution law of each blasting block can be determined according to the mass-fragmentation relationship: .
[0049] Where, is the size of the broken pieces, The crushed pieces are smaller than The cumulative mass of the explosion blocks, is the total mass of each explosive block, is the fractal dimension of the fragment size distribution of each explosive block.
[0050] We can also take the logarithm of the fragment size distribution of each blast block: , and is the horizontal axis, is the vertical axis, To fit the slope of the curve, the mass fractal dimension of each explosive block was obtained.
[0051] Next, numerical simulations of CO2-induced fracturing tube blasting can be performed based on physical blasting tests. Specifically, in one or more embodiments of the present invention, a rock specimen can be simulated using particle flow based on initial particle microscopic parameters, and a rock simulation specimen of the same size as the rock specimen can be constructed. At the location of the CO2-induced fracturing tube relative to the rock simulation specimen, explosive point particles with the same diameter as the CO2-induced fracturing tube are placed to simulate the blasting point. The explosive point particles then expand to generate a superposition force on the particles representing the rock mass surrounding the explosive point, thereby treating the CO2-induced fracturing tube as the explosive point particle. The blasting process of the CO2-induced fracturing tube is then simulated, and the velocity distribution, fragmentation size distribution, and mass fractal dimension of each explosive block during the simulated blasting process are determined as the distribution pattern of each explosive block during the simulated blasting process.
[0052] For example, the discrete element method (DEM) can be used to generate a rock simulation specimen with a size of 1.2m×1.2m×1.2m. The particle microscopic parameters between particles use any set of initial particle microscopic parameters obtained above. The bottom is used to simulate the ground with a wall. The blasting point is set at the same position as the physical test, such as Figure 4 As shown, Figure 4 This figure shows a numerical simulation of a CO2-induced fracturing tube blasting method used in this invention. The central circular particle represents the blasting point particle. The initial diameter of the blasting point particle is the same as that of the CO2 fracturing tube. A measuring circle is set around the blasting point particle. As the blasting point particle expands, it creates a superposition force on the surrounding rock particles, generating a blasting impact force.
[0053] The explosion of a carbon dioxide-induced fracturing pipe can be roughly regarded as propagating outward from the vent hole in the form of a spherical wave. In the granular flow, it is equivalent to a pulse stress wave. The pressure effect on the hole wall can be divided into a half-sine wave with the same rise and fall time: ,like Figure 5 As shown, Figure 5 This is a schematic diagram of a blasting stress wave in the present invention.
[0054] Where, is the peak pressure inside the hole at the target location, is the pressure action time, is the duration, is the gas pressure. Based on the peak pressure of the high-pressure gas in the carbon dioxide fracturing tube and the duration of action in the cavity, the changing trend of the force exerted on the rock inner wall during the entire process of carbon dioxide fracturing tube blasting can be obtained.
[0055] In terms of numerical simulation, the expansion of particles at the explosion point can be used to simulate the carbon dioxide-induced fracturing pipe according to the following formula: .
[0056] Where, is the radius expansion of the explosion point particle, is the contact stiffness between particles of the rock simulation specimen, is the initial diameter of the explosion point particle, It is the simulated hole explosion pressure for carbon dioxide induced fracturing pipe blasting.
[0057] According to the particle contact principle, the initial diameter of the explosion point particle is determined to be r , fix the position of the explosion point, increase the radius of the explosion particle, and after expansion, the explosion point particle contacts the rock particles and transmits pressure to the adjacent particles, thereby generating radial thrust on the surrounding rock particles. When the initial radius of the explosion point particle, the contact stiffness between particles, and the explosion pressure are known, the carbon dioxide fracturing tube blasting can be simulated by changing the radius of the explosion point particle.
[0058] As long as the particles in the rock simulation specimen are By changing the pressure, the blasting load can be simulated to act around the blasthole in the rock mass. When the particles at the blast point expand, shock waves are generated on the particles around the particles at the blast point in the rock simulation specimen, forming a crushing zone under radial compression. After crushing the rock simulation specimen, the shock waves decay into stress waves, generating tensile stress on the surface of the rock simulation specimen, causing the rock simulation specimen to break and form cracks. Figure 6 As shown, Figure 6 This is a schematic diagram of the ejection phenomenon of explosive blocks in a carbon dioxide fracturing tube blasting according to the present invention. Figure 6 The left side of the center shows a schematic diagram of the numerical simulation of rock sample expansion blasting, and the right side shows a schematic diagram of the numerical simulation of rock block ejection. After the simulation is completed, the velocity, block distribution, and fractal dimension of the rock ejection are obtained based on the pre-set measurement circle and post-processing. The numerical simulation results are compared with the physical test results. If the ejected rock is well restored, the accuracy of the numerical simulation model is confirmed. If there is a significant discrepancy between the numerical simulation results and the physical test results, the initial particle mesoscopic parameters are adjusted and the simulation is repeated until the phenomena are basically consistent (multiple sets of initial particle mesoscopic parameters can be selected to ensure that the blasting simulation and blasting test results are consistent, thus obtaining the final particle mesoscopic parameters). This constructs a first mapping relationship between the simulated parameters of the explosive point particles (expansion radius and layout) and the parameters of the CO2 fracturing tube, resulting in a blasting simulation model that can accurately simulate CO2 fracturing tube blasting based on the physical properties of the rock in the construction area.
[0059] Furthermore, in one or more embodiments of the present invention, after verifying the reliability of the numerical simulation of CO2 fracturing tube blasting, numerical simulations of different blasting conditions can be configured. These different blasting conditions include different blasting points and different blasting energies, with different blasting energies corresponding to different simulated hole explosion pressures. The radius expansion of the blasting point particles represents the peak pressure of CO2 within the CO2 fracturing tube, and the placement of the blasting point particles represents the installation location of the CO2 fracturing tube vent within the rock.
[0060] Table 1 Numerical simulation of carbon dioxide-induced fracturing pipe explosion under different working conditions
[0061]
[0062] For example, the peak pressure can be set to 150 MPa, 200 MPa, 250 MPa and 300 MPa respectively, and the blasting positions can be set to (0.6 m, 0.6 m, 0.2 m), (0.6 m, 0.6 m, 0.3 m), (0.6 m, 0.6 m, 0.4 m), and (0.6 m, 0.6 m, 0.5 m) respectively. The numerical simulation test of multi-condition control variables is set, as shown in Table 1.
[0063] After the test is completed, the numerical simulation results under different working conditions are recorded by measuring the circle. According to the numerical simulation results, the corresponding relationship between blasting pressure, blasting position, block ejection velocity and fractal dimension is obtained, and the distribution law of blasting blocks and ejection velocity after rock blasting are statistically analyzed.
[0064] During the simulation process, a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level can be constructed by combining real rockburst cases at different energy levels.
[0065] Rockburst is a dynamic phenomenon in which the elastic deformation energy accumulated in the rock mass is suddenly released under engineering disturbance, resulting in the explosion and ejection of surrounding rock. The main hazard of rockburst is the threat posed by the kinetic energy of the rock fragments to construction workers and machinery. Reducing the ejection phenomenon of rock fragments in tunnel rockburst dynamic hazards is of great significance for rockburst disaster prevention and control. Due to the different lithology, strength, and integrity of the surrounding rock, the volume and velocity of the ejected rocks also vary greatly. According to the current classification of rockburst energy levels, the velocity and range of rockburst rocks at different energy levels are shown in Table 2.
[0066] Table 2 Typical characteristics of different rockburst energy levels
[0067]
[0068] The numerical simulation results of carbon dioxide fracturing tube blasting are compared with real rock burst cases to find the most representative distribution of projectile blocks in each energy level rock burst, and establish a mapping relationship between the expansion radius and layout position of the explosion point particles and the rock burst energy level. Then, based on the expansion radius and layout position of the explosion point particles, the carbon dioxide fracturing tube parameters in the physical blasting test of carbon dioxide fracturing tube blasting are obtained, so as to achieve the purpose of restoring the dynamic disaster of real rock burst disaster by blasting rocks with carbon dioxide fracturing tube, and simulate rock burst by carbon dioxide fracturing tube blasting in the field.
[0069] based on Figure 1 The method for simulating rock burst by carbon dioxide fracturing tube blasting shown in the figure first obtains the particle micro-parameters reflecting the physical properties of the rock specimen, then conducts a carbon dioxide fracturing tube blasting test on the rock specimen, and determines the distribution pattern of the explosive blocks during the blasting process. Then, the carbon dioxide fracturing tube blasting is numerically simulated multiple times to correct the particle micro-parameters, and at the same time, a first mapping relationship between the simulation parameters of the explosive point particles in the numerical simulation and the carbon dioxide fracturing tube parameters is constructed. Finally, the carbon dioxide fracturing tube blasting under different blasting conditions is simulated by numerical simulation to match the real rock burst characteristics of different energy levels, and a second mapping relationship between the simulation parameters of the explosive point particles and the rock burst energy level is constructed. Based on the first mapping relationship and the second mapping relationship, the mapping relationship between the carbon dioxide fracturing tube parameters and rock bursts of different energy levels is determined, so as to simulate rock burst by carbon dioxide fracturing tube blasting in practice.
[0070] The impact process of carbon dioxide fracturing tube blasting is quite similar to that of the explosive blocks after rockburst. However, exploring how to accurately simulate rockburst through physical experiments with carbon dioxide fracturing tube blasting has safety risks and is costly.
[0071] The present invention takes a single carbon dioxide fracturing tube blasting test as a benchmark, adopts a particle flow discrete element modeling method to accurately simulate the carbon dioxide fracturing tube blasting test, corrects the particle micro-parameters reflecting the physical properties of the rock specimen through multiple simulations, and simultaneously determines the mapping relationship between the simulation parameters of the explosive point particles and the carbon dioxide fracturing tube parameters. Then, based on the corrected particle micro-parameters, the blasting process under different blasting conditions is simulated to match the real rockburst characteristics of different energy levels. The mapping relationship between the carbon dioxide fracturing tube blasting and the rockburst is accurately connected through the numerical simulation process, thereby obtaining an accurate mapping relationship between the carbon dioxide fracturing tube parameters and rockbursts of different energy levels, so that carbon dioxide fracturing tube blasting can be carried out in the field to accurately simulate rockbursts of the target energy level.
[0072] The present invention restores the actual rockburst and rock ejection phenomenon at the laboratory scale through physical blasting tests and numerical simulations of carbon dioxide fracturing tubes. Through fewer physical tests, the mapping relationship between carbon dioxide fracturing tube parameters and rockbursts of different energy levels is determined for application in field rockburst simulations, thereby improving the accuracy of field rockburst simulations.
[0073] When it is necessary to simulate a rockburst of a certain energy level, the rockburst simulation can be carried out directly on-site by carrying out carbon dioxide fracturing tube blasting using the corresponding carbon dioxide fracturing tube parameters. This can not only accurately simulate the rockburst to determine the threat level of rockburst rocks to the protection system, but also reduce the number of physical blasting tests, thereby reducing safety risks and costs.
[0074] When applying the method of simulating rock burst by blasting with carbon dioxide fracturing tube provided by the present invention, it is not necessary to Figure 1 The steps are executed in the order shown. The specific execution order of the steps can be determined according to needs, and the present invention does not limit this.
[0075] The above is a method for simulating rock burst by blasting a carbon dioxide fracturing tube provided by one or more embodiments of the present invention. Based on the same idea, the present invention also provides a corresponding device for simulating rock burst by blasting a carbon dioxide fracturing tube, such as Figure 7 shown.
[0076] Figure 7 A schematic diagram of a device for simulating rock burst by blasting a carbon dioxide fracturing tube is provided in the present invention, comprising:
[0077] A rock modeling module 201 is used to obtain particle microscopic parameters reflecting the physical properties of a rock specimen used for blasting to simulate rockburst;
[0078] Blasting test module 202, used to perform carbon dioxide fracturing tube blasting test on rock specimens;
[0079] The blasting simulation module 203 is configured to use a discrete element method to equate the CO2 fracturing tubes to explosive point particles, perform multiple simulations of the CO2 fracturing tube blasting to modify the particle microscopic parameters until the distribution pattern of the explosive particles is restored; and determine a first mapping relationship between the simulated parameters of the explosive point particles and the CO2 fracturing tube parameters;
[0080] Matching module 204 is used to simulate the blasting process under different blasting conditions using the discrete element method based on the corrected particle microscopic parameters and the explosion point particles with different simulation parameters, and match the real rockburst characteristics of different energy levels to establish a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level;
[0081] The simulated rock burst mapping module 205 is used to determine the mapping relationship between the CO2 fracturing tube parameters and rock bursts of different energy levels according to the first mapping relationship and the second mapping relationship, so as to simulate rock burst by blasting the CO2 fracturing tube in situ.
[0082] The specific definitions of the apparatus for simulating rockbursts via carbon dioxide fracturing tube blasting can be found in the above-mentioned definitions of the method for simulating rockbursts via carbon dioxide fracturing tube blasting, and will not be repeated here. Each module in the apparatus for simulating rockbursts via carbon dioxide fracturing tube blasting can be implemented in whole or in part via software, hardware, or a combination thereof. Each of these modules can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each of these modules.
[0083] The present invention also provides a computer-readable storage medium, which stores a computer program, which can be used to execute the above Figure 1 A method for simulating rock burst by blasting a carbon dioxide-induced fracturing tube is provided.
[0084] The present invention also provides a computer device. At the hardware level, the computer device includes a processor, an internal bus, a network interface, a memory, and a non-volatile memory. Of course, it may also include hardware required for other services. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it to achieve the above Figure 1 A method for simulating rock burst by blasting a carbon dioxide-induced fracturing tube is provided.
[0085] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware using a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes in the above-described method embodiments. Any reference to memory, storage, database, or other media used in the various embodiments provided herein may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).
[0086] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of the present invention.
Claims
1. A method for simulating rock burst by carbon dioxide fracturing tube blasting, characterized in that: include: Obtaining particle microscopic parameters that reflect the physical properties of rock specimens; A carbon dioxide fracturing tube blasting test was conducted on rock specimens. The ejection images of the explosive blocks collected during the blasting process were obtained to determine the ejection velocity of each explosive block. The velocity distribution of each explosive block was determined based on its size and distance from the target location. After blasting, the explosive blocks were divided into multiple levels according to their fragmentation size, and the cumulative mass of the explosive blocks corresponding to each level of fragmentation was determined. The fragmentation size distribution of each explosive block was determined using the following formula: ; Take the logarithm of the fragment size distribution of each blast block: , and is the horizontal axis, is the vertical axis, To fit the slope of the curve, the mass fractal dimension of each explosive block was obtained; Based on the particle microscopic parameters, a rock specimen was simulated using particle flow to construct a rock simulation specimen of the same size as the rock specimen. At the position of the CO2 fracturing tube relative to the rock specimen, explosive point particles with the same diameter as the CO2 fracturing tube were set. The blasting of the CO2 fracturing tube was simulated by the expansion of the explosive point particles according to the following formula: When the explosive point particles expand, shock waves are generated on the particles around the explosive point particles in the rock simulation specimen, forming a crushing zone under radial compression, and decaying into stress waves after crushing the rock simulation specimen, generating tensile stress on the surface of the rock simulation specimen, causing the rock simulation specimen to break and form cracks; the velocity distribution law, broken piece size distribution law and mass fractal dimension of each explosive block in the simulated blasting process are determined as the distribution law of each explosive block in the simulated blasting process, so as to correct the particle microscopic parameters until the distribution law of the explosive block is restored; and the first mapping relationship between the simulation parameters of the explosive point particles and the carbon dioxide fracturing tube parameters is determined; The discrete element method is used to simulate the blasting process under different blasting conditions based on the corrected particle microscopic parameters and the explosion point particles with different simulation parameters. The blasting characteristics of the real rockburst at different energy levels are matched, and a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level is constructed. Determining, based on the first mapping relationship and the second mapping relationship, a mapping relationship between carbon dioxide fracturing tube parameters and rock bursts of different energy levels, so as to simulate rock bursts by blasting the carbon dioxide fracturing tube in situ; in, is the size of the broken pieces, The crushed pieces are smaller than The cumulative mass of the explosion blocks, is the total mass of each explosive block, is the fractal dimension of the fragmentation distribution of each explosive block, is the radius expansion of the explosion point particle, is the contact stiffness between particles of the rock simulation specimen, is the initial diameter of the explosion point particle, It is the simulated hole explosion pressure for carbon dioxide induced fracturing pipe blasting.
2. The method for simulating rock burst by carbon dioxide fracturing tube blasting according to claim 1, characterized in that: The different blasting conditions include different blasting points and different blasting energies; the different blasting energies correspond to different simulated hole explosion pressures.
3. The method for simulating rock burst by carbon dioxide fracturing tube blasting according to claim 1, characterized in that: The step of obtaining the particle microscopic parameters reflecting the physical properties of the rock specimen specifically includes: Obtain rock samples corresponding to the rock specimens, perform uniaxial compression tests and Brazilian splitting tests on the rock samples, and obtain pressure stress-strain curves and tensile stress-strain curves of the rock samples as real test results; The rock sample is modeled with discrete element method at equal scale using particle flow, and initial microscopic parameters are assigned to each particle to obtain the initial rock simulation sample. Determine the pressure stress-strain curve and the tension stress-strain curve corresponding to the numerical simulation test results of the initial rock simulation sample, and modify the initial mesoscopic parameters according to the deviation between the numerical simulation test results of the rock simulation sample and the actual test results of the rock sample; Through multiple rounds of iterative correction, the numerical simulation test results are matched with the actual test results, and the particle micro-parameters reflecting the physical properties of the rock samples are obtained.
4. A device for simulating rock burst by blasting a carbon dioxide fracturing tube, characterized in that: include: Rock modeling module, used to obtain particle microscopic parameters reflecting the physical properties of rock specimens; The blasting test module is used to conduct carbon dioxide fracturing tube blasting tests on rock specimens, obtain the ejection images of the explosive blocks collected during the blasting process, and determine the ejection velocity of each explosive block. The velocity distribution of each explosive block is determined based on the size of each explosive block and the distance from the target position. After blasting, each explosive block is divided into multiple levels according to the fragmentation size, and the cumulative mass of the explosive block corresponding to each level of fragmentation size is determined. The fragmentation size distribution of each explosive block is determined using the following formula: ; Take the logarithm of the fragment size distribution of each blast block: , and is the horizontal axis, is the vertical axis, To fit the slope of the curve, the mass fractal dimension of each explosive block was obtained; The simulation blasting module is used to simulate the rock specimen using particle flow based on the particle microscopic parameters, and construct a rock simulation specimen with the same size as the rock specimen; at the position where the carbon dioxide fracturing tube is set relative to the rock simulation specimen, explosive point particles with the same diameter as the carbon dioxide fracturing tube are set; and the expansion of the explosive point particles is used to simulate the blasting of the carbon dioxide fracturing tube according to the following formula: When the explosive point particles expand, shock waves are generated on the particles around the explosive point particles in the rock simulation specimen, forming a crushing zone under radial compression, and decaying into stress waves after crushing the rock simulation specimen, generating tensile stress on the surface of the rock simulation specimen, causing the rock simulation specimen to break and form cracks; the velocity distribution law, broken piece size distribution law and mass fractal dimension of each explosive block in the simulated blasting process are determined as the distribution law of each explosive block in the simulated blasting process, so as to correct the particle microscopic parameters until the distribution law of the explosive block is restored; and the first mapping relationship between the simulation parameters of the explosive point particles and the carbon dioxide fracturing tube parameters is determined; The matching module is used to simulate the blasting process under different blasting conditions based on the modified particle microscopic parameters and the explosion point particles with different simulation parameters using the discrete element method, and to match the real rockburst characteristics at different energy levels, thereby constructing a second mapping relationship between the simulation parameters of the explosion point particles and the rockburst energy level; A rockburst simulation mapping module is used to determine a mapping relationship between carbon dioxide fracturing tube parameters and rockbursts of different energy levels based on the first mapping relationship and the second mapping relationship, so as to simulate rockbursts by blasting the carbon dioxide fracturing tube in situ; in, is the size of the broken pieces, The crushed pieces are smaller than The cumulative mass of the explosion blocks, is the total mass of each explosive block, is the fractal dimension of the fragmentation distribution of each explosive block, is the radius expansion of the explosion point particle, is the contact stiffness between particles of the rock simulation specimen, is the initial diameter of the explosion point particle, It is the simulated hole explosion pressure for carbon dioxide induced fracturing pipe blasting.
5. A computer-readable storage medium, characterized in that The storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 3 is implemented.
6. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 3 is implemented.