A method for accurately calculating the process of blasting gas wedging

Abstract

The application discloses a method for accurately calculating a blasting gas wedging process, which comprises the following steps: S1, establishing a geometric model of the blasting gas wedging process; S2, performing entity unit grid division on the model, and inserting a bonding unit between the entity units; S3, setting material parameters, a gas wedging opening parameter of the bonding unit and a blasting gas mechanical parameter; S4, under the same mechanical time step, calculating the volume of a cavity on a fracture zone according to the opening of a failed bonding unit; S5, under the same mechanical time step, performing multiple gas circulation calculations to obtain the gas pressure of each cavity on the fracture zone; S6, after the gas circulation calculation is completed, calculating and updating related parameters by using the calculation results in the steps S4 and S5, and judging and updating the connection state of the bonding unit and the crack geometric characteristics according to a constitutive relation; and S7, repeating the steps S4-S6 until the whole blasting rock breaking process simulation is completed.

Description

Technical Field

[0001] This invention relates to the field of blasting analysis technology, specifically to a method for accurately calculating the wedge-in process of blasting generated gases. Background Technology

[0002] Blasting technology is widely used in mining, tunneling, and other fields. The rock-breaking process of blasting can be understood as the detonation of explosives producing high-energy gases. High-pressure gas molecules rapidly impact the borehole wall, forming an explosive stress wave. This creates a crushing zone and an initial fracture zone around the borehole wall. When the pressure and temperature inside the borehole decrease to a certain level, the gas molecules tend to stabilize, and the gas wefts into the crack, generating pressure and further promoting crack propagation. However, existing blasting theories do not fully consider the role of explosive gases in the blasting process, and the understanding of the rock-breaking mechanism of explosive gases is unclear, making it difficult to effectively guide blasting construction. Considering that traditional physical experiments cannot measure the action of explosive gases, numerical simulation methods can simulate blasting conditions under different blasting parameters and different explosive gas pressures, accurately predicting the rock mass fragmentation range and vibration effects during blasting. This can provide a scientific basis for optimizing blasting parameters and improve engineering quality and safety.

[0003] Currently, there is a lack of a direct and effective method to simulate the crack propagation process driven by explosive gases. Most numerical simulations of blasting oversimplify the treatment of explosive gases: they are typically modeled by simply calculating gas pressure or applying equivalent pressure curves, and the gas pressure is treated as an external load applied to the blast cavity or crack wall to characterize its effect on the rock mass. However, the actual evolution of explosive gas infiltration and crack propagation is extremely complex. As a compressible gas, the volume of explosive gas under high temperature and pressure is significantly affected by pressure changes. Simultaneously, its flow velocity is high during continuous infiltration into the crack, resulting in a non-laminar flow state and complex pressure gradient changes within the crack. Existing methods cannot effectively simulate these key characteristics of explosive gas action and cannot accurately simulate the dynamic process of gas-driven crack propagation.

[0004] Therefore, it is necessary to propose a method for accurately calculating the wedge-in process of explosive gases during blasting. Summary of the Invention

[0005] The purpose of this invention is to provide a method for accurately calculating the wedge-in process of explosive gases during blasting, in order to solve the technical problems existing in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for accurately calculating the wedge-in process of explosive gases during blasting includes the following steps:

[0008] S1. Establish a geometric model of the blasting gas weft-in process and set the model shape, size and boundary;

[0009] S2, perform solid element meshing on the model, insert bonding elements between solid elements, initialize the gas cavity linked list, establish its mesh node correspondence, when the bonding element connected to the explosive fails and disconnects, a fracture zone is formed, and the corresponding bonding element is called the failed bonding element.

[0010] S3, set material parameters, bonding unit gas wedge opening parameters, and explosive gas mechanical parameters;

[0011] S4, under the same mechanical time step, calculate the gas volume of the cavity above the fracture zone based on the opening of the failed bonding unit;

[0012] S5, under the same mechanical time step, perform multiple gas circulation calculations to obtain the gas pressure of each cavity in the rupture zone;

[0013] S6. After the gas circulation calculation is completed, the calculation results in steps S4 and S5 are used to perform Newton's second law equilibrium calculation and update the relevant mechanical parameters. The connection state and crack geometry of the bonding unit are judged and updated according to the constitutive relation.

[0014] S7. Repeat steps S4-S6 until the entire blasting and rock breaking process simulation is completed.

[0015] Further, in step S3, the gas wedge opening parameters of the bonding unit include the initial opening of the bonding unit, the upper limit opening, and the lower limit opening;

[0016] The mechanical parameters of the explosive gas include the gas adiabatic index, initial gas bulk modulus, initial gas density, initial explosive gas pressure, and explosive location.

[0017] Furthermore, in step S4, when calculating the gas volume of the cavity above the rupture zone based on the opening degree of the failed bonding unit, the specific steps include the following:

[0018] S41, the opening of each failed bonded unit is calculated using the following formula:

[0019]

[0020] In the formula, a is the crack aperture, a0 is the initial crack aperture, and a max and a min These are the upper limit crack aperture and the lower limit crack aperture, respectively. The average crack aperture;

[0021] S42, Calculate the gas volume of each node in a single failed bonded element based on the opening degree. If the geometric model established in step S1 is a two-dimensional model, then for a two-dimensional bonded element, the gas volume is calculated using the following formula:

[0022]

[0023] If the geometric model established in step S1 is a three-dimensional model, then for the three-dimensional bonding element, the gas volume is calculated using the following formula:

[0024]

[0025] In the formula, L is the length of the common edge of a two-dimensional bonding element and an adjacent solid element, S is the area of ​​the common surface of a three-dimensional bonding element and an adjacent solid element, and n is the number of nodes of the bonding element. n is 4 in the two-dimensional model and 6 in the three-dimensional model.

[0026] S43, based on the node volume, further solve for the gas volume of each bonding element node contained in the cavity above the fracture zone:

[0027]

[0028] S44, sum up the gas volume occupied by all bonding unit nodes contained in the cavity above the fracture zone to obtain the gas volume of the cavity:

[0029] .

[0030] Furthermore, step S5 specifically includes the following steps:

[0031] S51, initialize the system to set the gas volume of all cavities to 0;

[0032] S52, update the gas density based on the previous gas calculation time step. and bulk modulus :

[0033]

[0034]

[0035] In the formula, Let P0 be the initial gas density, P1 be the initial gas pressure, and P2 be the current gas pressure, obtained from the previous gas calculation time step. The gas adiabatic index;

[0036] S53, For any fractured cavity, calculate the influence coefficient of the gas saturation of the fractured cavity on the gas flow rate:

[0037]

[0038] In the formula, The gas saturation of the cavity is obtained from the previous gas calculation time step;

[0039] S54, Calculate the gas velocity at any bonded element node i in the cavity:

[0040]

[0041] In the formula These are the gas densities of bonding element node i and its connected bonding element node j calculated at this gas calculation time step. The density of the two bonded element nodes in the previous gas calculation time step. Let be the gas permeability coefficient. The gas pressure difference between bonding unit nodes i and j, and b is a user-defined coefficient;

[0042] S55, sum the gas flow velocities of all bonded unit nodes within the cavity to obtain the total gas flow velocity of the cavity:

[0043]

[0044] S56, Calculate the gas saturation of each cavity:

[0045]

[0046] In the formula The saturation of the cavity at the current gas calculation time step. The saturation of the cavity in the previous gas calculation time step, i.e., in step S53 , For gas calculation time step, and These are the volumes of the cavity at the current and previous time steps, respectively. satisfy ;

[0047] S57, the gas pressure of each cavity is calculated from the flow velocity of each cavity:

[0048]

[0049] In the formula The gas pressure in the cavity at the current gas calculation time step. The gas pressure in the cavity during the previous gas calculation time step. The bulk modulus of the gas. For gas calculation time step;

[0050] After calculating the gas pressure of all cavities, the gas pressure distribution of the rupture zone cavities at this gas calculation time step is obtained.

[0051] S58. Repeat steps S51-S57 to continuously update the gas pressure distribution. After reaching the specified number of gas cycle calculations, stop the calculation and use the calculation result obtained from the last gas cycle calculation as the explosion gas pressure distribution for this mechanical time step to participate in the mechanical calculation.

[0052] Furthermore, in step S54, the gas pressure difference between bonding unit nodes i and j Calculated using the following formula:

[0053]

[0054] In the formula, These represent the gas pressures at bonding element node i and bonding element node j, respectively. ρ is the gas density, and g is the acceleration due to gravity.

[0055] Furthermore, in step S57, after calculating the gas pressure of each cavity, the gas pressure experienced by each solid unit adjacent to the cavity is also calculated. For a two-dimensional model, it is calculated using the following formula:

[0056]

[0057] For 3D models, the following formula is used for calculation:

[0058]

[0059] In the formula, L is the length of the common side of a two-dimensional bonding unit and an adjacent solid unit, and S is the area of ​​the common surface of a three-dimensional bonding unit and an adjacent solid unit. Thus, the gas pressure distribution of the explosive gas during the seepage process in the rupture zone is obtained.

[0060] Furthermore, in step S7, specifically, steps S4-S6 are repeated, the gas pressure changes are updated by gas, the mechanical calculation results of the rupture are performed, and the calculation ends when the specified total time step is reached, thus completing the simulation of the entire explosive gas blasting and rock breaking process.

[0061] Compared with the prior art, the advantages of the present invention are as follows:

[0062] Existing methods for simulating explosive gases cannot accurately simulate the crack propagation process driven by explosive gases. This invention provides a method for accurately calculating the wedge-in process of explosive gases during blasting within the framework of the finite-discrete element method. This method solves the above-mentioned problems of existing simulation methods, can accurately calculate the velocity change of explosive gases in the crack, and accurately characterize the crack propagation process driven by explosive gases. This is of great significance for accurately simulating the action process of explosive gases. Attached Figure Description

[0063] To more clearly illustrate the technical solutions in this embodiment, the accompanying drawings used in the description of the embodiment will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0064] Figure 1 This is a flowchart illustrating a method for accurately calculating the wedge-in process of explosively generated gases provided by the present invention.

[0065] Figure 2 This is a schematic diagram of the crack propagation process driven by explosive gas.

[0066] Figure 3 This is a schematic diagram of the cavity in the fractured area;

[0067] Figure 4 This is a schematic diagram of a bonding unit that connects two-dimensional triangular solid units and three-dimensional tetrahedral solid units respectively;

[0068] Figure 5 This is a schematic diagram of a bonding unit and the two triangular solid units connected to it;

[0069] Figure 6 This is a schematic diagram of a bonding unit and the two tetrahedral solid units connected to it;

[0070] Figure 7 This is a schematic diagram of a cavity connected to multiple gas seepage channels. Detailed Implementation

[0071] To make the technical means, creative features, objectives and effects of this invention easier to understand, the following description, in conjunction with the accompanying drawings and specific embodiments, further explains how this invention is implemented.

[0072] In one specific embodiment, refer to Figure 1 As shown, the present invention provides a method for accurately calculating the wedge-in process of explosive gases during blasting, comprising the following steps:

[0073] S1. Establish a geometric model of the explosion-generated gas wedge-in process and set the model shape, size and boundary; the established geometric model can be a two-dimensional model or a three-dimensional model.

[0074] S2, perform solid element meshing on the model, insert bonding elements between solid elements, initialize the gas cavity linked list, establish the correspondence between its mesh nodes, when the bonding element connected to the explosive fails and disconnects, a fracture zone (crack) is formed, and the corresponding bonding element is called the failed bonding element.

[0075] Understandably, gas flow occurs between the explosive and the fracture zone. The explosive gas wedges into the fracture zone and acts on the surrounding solid elements, driving them to expand outwards. This causes more bonded elements to fail, and the fracture zone continuously expands, thus simulating the propagation of cracks driven by explosive gas. Figure 2 As shown.

[0076] S3, set material parameters, bonding unit gas wedge opening parameters, and explosive gas mechanical parameters.

[0077] Specifically, the material parameters include material density, elastic modulus, Poisson's ratio, setting the tensile strength of the bonding element, and setting the perimeter of the model as an absorbing boundary; the bonding element gas wedge opening parameters include the initial opening, upper limit opening, and lower limit opening of the bonding element; the explosive gas mechanical parameters include the gas adiabatic index, initial gas bulk modulus, initial gas density, initial explosive gas pressure, and explosive position.

[0078] S4, at the same mechanical time step, calculate the gas volume of the cavity above the fracture zone based on the opening of the failed bonding unit.

[0079] like Figure 3 As shown, the gas pressure is generated due to the explosive gas filling the cavities in the rupture zone ( Figure 3 Between 1, 2, ..., 15, gas exchange occurs through the failed bonding unit. Therefore, the essence of simulating the explosive gas-driven crack propagation process is to calculate the pressure effect of the explosive gas on the bonding unit in the fracture zone. The core of this solution process is to calculate the gas pressure of the explosive gas on each cavity in the fracture zone. Before solving for the gas pressure, the gas volume of each cavity needs to be calculated. The volume of the cavity in the fracture zone can be calculated based on the opening of the failed bonding unit.

[0080] The calculation of the gas volume in the cavity above the rupture zone based on the opening of the failed bonding unit includes the following steps:

[0081] S41, for the calculation of the opening of the bonding unit, Figure 4 Taking a bonded element connecting triangular solid elements and tetrahedral solid elements as an example, for a two-dimensional bonded element, calculate the opening of the bonded element, such as... Figure 5Consider a bonded element and two connected triangular solid elements. The nodes of the bonded element are nodes 1, 2, 3, and 4, and the midpoints of the two sides of the bonded element are nodes 5 and 6. A rectangular coordinate system is established with the normal and parallel directions of the line connecting the midpoints (nodes 5 and 6) of the bonded element as the x and y directions, and the midpoint O of the line connecting the midpoints as the origin. Under this coordinate system, the coordinates (x, y) of the two pairs of opposite nodes 1, 2, 3, 4 and the pair of midpoints 5, 6 of the quadrilateral surface are obtained. i ,y i If i = 1, 2, ..., 6, then the opening degree of each group of relative points is:

[0082]

[0083] In the formula y m y n These are the ordinates of a set of relative points.

[0084] For a three-dimensional bonded element, when calculating the opening of the bonded element, such as Figure 6 Consider a bonding element and two connected tetrahedral elements. The nodes of the bonding element are nodes 1, 2, 3, 4, 5, and 6. The centroids of the two faces of the bonding element are nodes 7 and 8. The direction of the line connecting the centroids (nodes 7 and 8) of the top and bottom faces of the bonding element is taken as the z-direction. Two mutually perpendicular directions perpendicular to the z-direction are taken as the x and y directions. A spatial rectangular coordinate system is established with centroid 8 of one face of the bonding element as the origin. Under this coordinate system, the coordinates (x, y) of two pairs of opposite nodes 1, 2, 3, 4 and one pair of midpoints 5, 6 of the tetrahedral face are obtained. i ,y i， z i If i = 1, 2, ..., 8, then the opening degree O of each group of relative points is... i for:

[0085]

[0086] In the formula z m z n These are the z-axis coordinates of a set of relative points.

[0087] Then the average crack aperture of the bonded unit can be calculated:

[0088]

[0089] In the formula, N is the total number of relative nodes and relative midpoints of the bonding element. For a two-dimensional triangular element, N=3; for a three-dimensional tetrahedral element, N=4.

[0090] Then, the opening of each failed bonded unit can be calculated using the following formula:

[0091]

[0092] In the formula, a is the crack aperture, a0 is the initial crack aperture, and a max and a min These are the upper limit crack aperture and the lower limit crack aperture, respectively. The average crack opening.

[0093] S42, Calculate the gas volume of each node in a single failed bonded element based on the opening degree. If the geometric model established in step S1 is a two-dimensional model, then for a two-dimensional bonded element, the gas volume is calculated using the following formula:

[0094]

[0095] If the geometric model established in step S1 is a three-dimensional model, then for the three-dimensional bonding element, the gas volume is calculated using the following formula:

[0096]

[0097] In the formula, L is the length of the common edge of a two-dimensional bonding element and an adjacent solid element, S is the area of ​​the common surface of a three-dimensional bonding element and an adjacent solid element, and n is the number of nodes of the bonding element. n is 4 in the two-dimensional model and 6 in the three-dimensional model.

[0098] S43, based on the node volume, further solve for the gas volume of each bonding element node contained in the cavity above the fracture zone:

[0099]

[0100] like Figure 7 As shown, a cavity connects multiple failed bonding units (gas permeation channels), including bonding unit nodes 1, 2, 3, 4, 5, and 6. Taking bonding unit node 3 as an example... , where V 31 V represents the gas volume of node 3 within the bonding unit composed of nodes 3, 4, 10, and 9. 32 Let 3 be the gas volume in the bonding unit composed of nodes 2, 3, 8, and 7.

[0101] S44, summing the gas volumes occupied by all bonding unit nodes within the cavity in the fractured region, yields the volume of the cavity:

[0102] .

[0103] S5, under the same mechanical time step, performs multiple gas circulation calculations to obtain the gas pressure of each cavity in the rupture zone. Specifically, this includes the following steps:

[0104] S51, initialize the system to set the gas volume of all cavities to 0;

[0105] S52, update the gas density based on the previous gas calculation time step. and bulk modulus :

[0106]

[0107]

[0108] In the formula, Let P0 be the initial gas density, P1 be the initial gas pressure, and P2 be the current gas pressure, obtained from the previous gas calculation time step. This represents the gas's adiabatic index. Because gases are compressible, changes in their pressure significantly affect their volume and density, thus influencing the calculation results. Therefore, the gas density and bulk modulus need to be updated based on changes in gas pressure during the calculation process.

[0109] S53, For any fractured cavity, considering the influence of gas saturation on gas pressure when gas wedges into the crack, calculate the influence coefficient of saturation on flow velocity of the fractured cavity:

[0110]

[0111] In the formula, The gas saturation of the cavity is obtained from the previous gas calculation time step.

[0112] S54, Calculate the gas velocity at any bonded element node i in the cavity:

[0113]

[0114] In the formula These are the gas densities of bonding element node i and its connected bonding element node j calculated at this gas calculation time step. The density of the two bonded element nodes in the previous gas calculation time step. Let be the gas permeability coefficient. is the gas pressure difference between bonding unit nodes i and j, and b is a user-defined coefficient.

[0115] Gas pressure difference between bonding unit nodes i and j Calculated using the following formula:

[0116]

[0117] In the formula, These represent the gas pressures at bonding element node i and bonding element node j, respectively. ρ is the gas density, and g is the acceleration due to gravity.

[0118] like Figure 7 As shown, a cavity contains multiple bonding element nodes i (i=1,2,…,6). Gas exchange occurs between different cavities through failed bonding elements. Gas exchange within each cavity is caused by gas exchange between the bonding element nodes contained within the cavity and the bonding element nodes connected to them, as shown... Figure 7 Nodes 2 and 7, 3 and 8, 3 and 9, 4 and 10, 5 and 11, 6 and 12 are used as nodes. Therefore, the flow velocity of each bonding unit node in the cavity is first calculated using the above method.

[0119] S55, sum the gas flow velocities of all bonded unit nodes within the cavity to obtain the total gas flow velocity of the cavity:

[0120] .

[0121] S56, Calculate the gas saturation of each cavity:

[0122]

[0123] In the formula The gas saturation of the cavity at the current gas calculation time step. The gas saturation of the cavity in the previous gas calculation time step. For gas calculation time step, and These are the volumes of the cavity at the current and previous time steps, respectively. satisfy .

[0124] S57, the gas pressure of each cavity is calculated from the gas flow rate of each cavity:

[0125]

[0126] In the formula The gas pressure in the cavity at the current gas calculation time step. The gas pressure in the cavity during the previous gas calculation time step. The bulk modulus of the gas. The time step is defined as follows: after calculating the gas pressure of all cavities, the gas pressure distribution of the rupture zone cavities at this gas calculation time step is obtained.

[0127] After calculating the gas pressure in each cavity, the gas pressure on each solid unit adjacent to the cavity is also calculated. For a two-dimensional model, it is calculated using the following formula:

[0128]

[0129] For 3D models, the following formula is used for calculation:

[0130]

[0131] In the formula, L is the length of the common side of a two-dimensional bonding unit and an adjacent solid unit, and S is the area of ​​the common surface of a three-dimensional bonding unit and an adjacent solid unit. Thus, the gas pressure distribution of the explosive gas during the seepage process in the rupture zone is obtained.

[0132] S58. Repeat steps S51-S57 to continuously update the gas pressure distribution. After reaching the specified number of calculation cycles, stop the calculation and use the calculation result obtained from the last gas cycle calculation as the explosion gas pressure distribution for this mechanical time step to participate in the mechanical calculation.

[0133] S6. After the gas circulation calculation is completed, the calculation results in steps S4 and S5 are used to perform Newton's second law equilibrium calculation and update the relevant mechanical parameters, such as nodal forces, nodal displacements, nodal velocities, solid element stresses, solid element strains, bonding element forces, bonding element openings, and bonding element sliding displacements within the calculation domain. The connection state and crack geometry of the bonding elements are determined and updated based on the constitutive relation. The calculation methods for these parameters are conventional techniques, such as the finite discrete element method, and will not be elaborated here.

[0134] S7. Repeat steps S4-S6, update the gas pressure change through gas updates, perform mechanical calculations on the fracture results, and end the calculation when the specified total time step is reached. The simulation of the entire explosive gas blasting and rock breaking process is completed.

[0135] Existing methods for simulating explosive gases cannot accurately simulate the crack propagation process driven by explosive gases. This invention provides a method for accurately calculating the wedge-in process of explosive gases during blasting within the framework of the finite-discrete element method. This method solves the above-mentioned problems of existing simulation methods, can accurately calculate the velocity change of explosive gases in the crack, and accurately characterize the crack propagation process driven by explosive gases. This is of great significance for accurately simulating the action process of explosive gases.

[0136] Finally, it should be noted that the above description is only an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for accurately calculating the wedge-in process of explosive gases during blasting, characterized in that, Includes the following steps: S1. Establish a geometric model of the blasting gas weft-in process, and set the model shape, size and boundary; S2, perform solid element meshing on the model, insert bonding elements between solid elements, initialize the gas cavity linked list, establish its mesh node correspondence, when the bonding element connected to the explosive fails and disconnects, a fracture zone is formed, and the corresponding bonding element is called the failed bonding element. S3, set material parameters, bonding unit gas wedge opening parameters, and explosive gas mechanical parameters; S4, under the same mechanical time step, calculate the gas volume of the cavity above the fracture zone based on the opening of the failed bonding unit; S5, under the same mechanical time step, perform multiple gas circulation calculations to obtain the gas pressure of each cavity in the rupture zone; S6. After the gas circulation calculation is completed, the calculation results in steps S4 and S5 are used to perform Newton's second law equilibrium calculation and update the relevant mechanical parameters. The connection state and crack geometry of the bonding unit are judged and updated according to the constitutive relation. S7. Repeat steps S4-S6 until the entire blasting and rock breaking process simulation is completed. Step S5 specifically includes the following steps: S51, initialize the system to set the gas volume of all cavities to 0; S52, update the gas density based on the previous gas calculation time step. and bulk modulus : ； ； In the formula, Let P0 be the initial gas density, P1 be the initial gas pressure, and P2 be the current gas pressure, obtained from the previous gas calculation time step. The gas adiabatic index; S53, For any fractured cavity, calculate the influence coefficient of the gas saturation of the fractured cavity on the gas flow rate: ； In the formula, The gas saturation of the cavity is obtained from the previous gas calculation time step; S54, Calculate the gas velocity at any bonded element node i in the cavity: ； In the formula These are the gas densities of bonding element node i and its connected bonding element node j calculated at this gas calculation time step. The gas density at the two bonded element nodes in the previous gas calculation time step. Let be the gas permeability coefficient. is the gas pressure difference between nodes i and j of the bonding element, b is a user-defined coefficient, a is the crack aperture, and L is the length of the common edge of a two-dimensional bonding element and its adjacent solid element. S55, sum the gas flow velocities of all bonded unit nodes within the cavity to obtain the total gas flow velocity of the cavity: ； S56, Calculate the gas saturation of each cavity: ； In the formula The gas saturation of the cavity at the current gas calculation time step. The gas saturation of the cavity in the previous gas calculation time step is calculated, i.e., in step S53. , For gas calculation time step, and These are the volumes of the cavity at the current and previous time steps, respectively. satisfy ; S57, the gas pressure of each cavity is calculated from the gas flow rate of each cavity: ； In the formula The gas pressure in the cavity at the current gas calculation time step. The gas pressure in the cavity during the previous gas calculation time step. The bulk modulus of the gas. For gas calculation time step; After calculating the gas pressure of all cavities, the gas pressure distribution of the rupture zone cavities at this gas calculation time step is obtained. S58. Repeat steps S51-S57 to continuously update the gas pressure distribution. After reaching the specified number of gas cycle calculations, stop the calculation and use the calculation result obtained from the last gas cycle calculation as the explosion gas pressure distribution for this mechanical time step to participate in the mechanical calculation.

2. The method for accurately calculating the wedge-in process of explosive gases according to claim 1, characterized in that, In step S3, the gas wedge opening parameters of the bonding unit include the initial opening of the bonding unit, the upper limit opening, and the lower limit opening; The mechanical parameters of the explosive gas include the gas adiabatic index, initial gas bulk modulus, initial gas density, initial explosive gas pressure, and explosive location.

3. The method for accurately calculating the wedge-in process of explosive gases according to claim 2, characterized in that, In step S4, when calculating the gas volume of the cavity above the rupture zone based on the opening degree of the failed bonding unit, the specific steps include the following: S41, the opening of each failed bonded unit is calculated using the following formula: ； In the formula It is the initial crack opening. and These are the upper limit crack aperture and the lower limit crack aperture, respectively. The average crack aperture; S42, Calculate the gas volume of each node in a single failed bonded element based on the opening degree. If the geometric model established in step S1 is a two-dimensional model, then for a two-dimensional bonded element, the gas volume is calculated using the following formula: ； If the geometric model established in step S1 is a three-dimensional model, then for the three-dimensional bonding element, the gas volume is calculated using the following formula: ； In the formula, S is the area of ​​the common surface between a three-dimensional bonding element and an adjacent solid element, and n is the number of nodes of the bonding element. n is 4 in the two-dimensional model and 6 in the three-dimensional model. S43, based on the node volume, further solve for the gas volume of each bonding element node contained in the cavity above the fracture zone: ； S44, sum up the gas volume occupied by all bonding unit nodes contained in the cavity above the fracture zone to obtain the gas volume of the cavity: 。 4. The method for accurately calculating the wedge-in process of explosive gases according to claim 3, characterized in that, In step S54, the gas pressure difference between bonding unit nodes i and j Calculated using the following formula: ； In the formula, These represent the gas pressures at bonding element node i and bonding element node j, respectively.

5. The method for accurately calculating the wedge-in process of explosive gases according to claim 4, characterized in that, In step S57, after calculating the gas pressure of each cavity, the gas pressure of each solid unit adjacent to the cavity is also calculated. For a two-dimensional model, it is calculated using the following formula: ； For 3D models, the following formula is used for calculation: ； In the formula, L is the length of the common side of a two-dimensional bonding unit and an adjacent solid unit, and S is the area of ​​the common surface of a three-dimensional bonding unit and an adjacent solid unit. Thus, the gas pressure distribution of the explosive gas during the seepage process in the rupture zone is obtained.

6. The method for accurately calculating the wedge-in process of explosive gases according to claim 5, characterized in that, In step S7, specifically, steps S4-S6 are repeated, the gas pressure changes are updated, the fracture results are mechanically calculated, and the calculation ends when the specified total time step is reached, thus completing the simulation of the entire explosive gas blasting and rock breaking process.

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