Axial air interval charging hole wall explosion load determination method and system

Abstract

The invention provides a method and a system for determining an explosion load of an axial air interval charging hole wall, and belongs to the technical field of numerical simulation of explosive mechanics and geotechnical engineering. According to the method, theoretical analysis and derivation are carried out on the explosion process of the charging section, a calculation method for the load peak values of the charging section and the air section is established, and the load peak values serve as key parameters to be reasonably given to a load duration curve of each node of a blast hole wall. According to the method, the obvious difference between the charging section and the air section is fully considered, and the load applying modes under different charging structure conditions are distinguished, so that the constructed blast hole wall load curve better conforms to the actual explosion process in the aspects of peak value characteristics, action time history and spatial distribution. The method is clear in calculation process, clear in physical significance, suitable for various axial charging structural forms, capable of effectively improving the accuracy of drilling and blasting numerical simulation and engineering analysis results and good in engineering application value.

Description

Technical Field

[0001] This invention belongs to the field of explosion mechanics and geotechnical engineering testing technology, specifically involving a method for determining and defining the load distribution characteristics on the borehole wall under different charge structure conditions. It is particularly suitable for the analysis of the law of explosion load action in rock and soil media, the establishment of numerical simulation input parameters, and the study of rock breaking efficiency. Background Technology

[0002] In fields such as rock and soil blasting, geological exploration, and protective engineering, explosive load is a crucial fundamental parameter for studying the response and failure mechanisms of a medium. During borehole blasting, the high-pressure gas and shock wave generated by the explosive detonation act on the borehole wall, forming a complex transient load distribution. The temporal characteristics and spatial distribution of this load are not only related to the properties of the medium but also influenced by the charge structure, including the axial decoupling coefficient, the position of the explosive charge, the interstitial medium, the sealing material, and the length of the charge.

[0003] Existing research applies only one type of explosive load curve to the borehole wall, without distinguishing between the charge section and the air section. For example, invention patent CN112052574A proposes a method for calculating the amount of explosive in pre-splitting blasting without coal pillars and roof cutting, in which the same load is applied to the borehole wall for radially or axially uncoupled charges. However, in reality, the peak load in the air section is much smaller than that in the charge section. This indicates that traditional methods cannot accurately reflect the influence of changes in the charge structure on the borehole wall load distribution curve, resulting in inaccurate input of the load curve in numerical simulations and affecting the reliability of blasting design and structural response prediction.

[0004] Therefore, there is an urgent need to propose a method that can effectively define the borehole wall load curve according to different charge structure forms (such as continuous charge, segmented charge, interval charge, etc.) in order to more realistically describe the spatial distribution characteristics of the explosive load on the borehole wall and provide a reliable basis for blasting effect analysis and numerical simulation. Summary of the Invention

[0005] To overcome the problems of inaccurate definition and poor versatility of borehole wall load curves under different charge structures in existing technologies, a method is proposed to determine the time history and spatial distribution characteristics of the explosive load on the borehole wall based on the characteristics of the charge form and the peak values ​​of the explosive load in the explosive section and the air section.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first aspect of this invention provides a method for determining the explosive load on the wall of an axially spaced air-gap charging hole, comprising the following steps: S1, Obtain the structural characteristic parameters of the borehole blasting, including explosive performance parameters, borehole geometric parameters, charge structure parameters, and blasting surrounding medium parameters; S2, Based on the structural characteristic parameters, design multiple sets of single-hole charging structure working conditions, which are determined by adjusting the axial decoupling coefficient, the number of axial air gap segments, and the decoupling medium; S3, based on the theory of explosion mechanics, analyzes the propagation, reflection and transmission laws of shock waves at different medium interfaces during the explosion of the charge section, and calculates the peak value of the blast load and the characteristics of the load time history curve of the charge section and the air section under each working condition. S4. Based on the peak value of the blasting load and the characteristics of the load time history curve, construct the load duration curve for each node of the borehole wall. Combined with the difference in peak load between the charge section and the air section, divide the load duration curve into segments and apply them to the corresponding nodes.

[0007] Preferably, in step S1, the explosive performance parameters include explosive density, detonation velocity, heat of explosion, detonation pressure, and Grüneisen coefficient; the borehole geometric parameters include borehole diameter, length, and plugging length; the charge structure parameters include charge length, charge position, number of axial air gaps, and axial decoupling coefficient; and the blasting surrounding medium parameters include medium density, impact compression empirical constant, and wave impedance.

[0008] Preferably, in step S2, the charge structure includes a continuous charge structure, a segmented charge structure, and a charge structure with axial air gaps; the uncoupled medium is air.

[0009] Preferably, in step S3, when calculating the peak value of the blasting load, the initial shock wave back pressure is derived by using the mass conservation equation, momentum conservation equation and Hugoniot equation, and the pressure relationship before and after the rarefaction wave is solved by combining the Murnaghan isentropic formula, and the transmitted shock wave pressure is determined by considering the difference in medium wave impedance.

[0010] Preferably, in step S4, based on the significant difference in the peak blast load between the charge section and the air section, the load duration curves of different nodes on the borehole wall are assigned values ​​respectively.

[0011] Preferably, in step S4, the load duration curve of the borehole wall adopts an exponential decay curve, which is used to reflect the characteristics of the rising and decaying segments of the explosive load.

[0012] Preferably, the method is applicable to the blasting response analysis of rock, concrete or soil media, and is used for the simulation of the duration of explosive blasting load in numerical simulation and theoretical calculation.

[0013] A second aspect of the present invention provides a system for determining the explosive load on the wall of an axially spaced air-gap charging hole, for implementing the method described above, the system comprising: The parameter acquisition module is used to acquire the structural characteristic parameters of borehole blasting, including explosive performance parameters, borehole geometric parameters, charge structure parameters, and parameters of the surrounding medium of the blasting. The working condition design module is used to design multiple sets of single-hole charging structure working conditions based on the structural characteristic parameters. The working conditions are determined by adjusting the axial decoupling coefficient, the number of axial air gap segments, and the decoupling medium. The load calculation module is used to analyze the propagation, reflection and transmission of shock waves at different medium interfaces during the explosion of the charge section based on the theory of explosion mechanics, and to calculate the peak value of the blast load and the characteristics of the load time history curve of the charge section and the air section under various working conditions. The load application module is used to construct the load duration curve of each node of the borehole wall based on the peak value of the blasting load and the characteristics of the load time history curve. Combining the difference in the peak load of the charge section and the air section, the load duration curve is segmented and applied to the corresponding node.

[0014] Preferably, it also includes a data storage module for storing the structural characteristic parameters, working condition parameters, peak blast load, load time history curve characteristics, and load duration curve data. It also includes a result output module, which is used to output the load duration curves and blast load distribution results of each node of the borehole wall.

[0015] Preferably, the load calculation module incorporates an explosion mechanics theoretical calculation model, which integrates the mass conservation equation, momentum conservation equation, Hugoniot equation, and Murnaghan isentropic formula. The load application module has a built-in exponential decay curve generation unit, which is used to generate a corresponding load duration curve based on the peak value of the blasting load and the characteristics of the load time history curve.

[0016] The present invention has the following beneficial effects: 1. Breaking through the limitations of traditional empirical assumptions, a quantitative mapping relationship between the structural characteristics of the charge and the load distribution on the borehole wall is established through derivation of the theory of explosion mechanics. This eliminates the need to rely on unified empirical load assumptions and improves the scientific nature of load determination.

[0017] 2. Taking full account of the difference in peak load between the charge section and the air section, the load is applied in segments, which realistically reproduces the propagation and evolution process of the explosive load in the borehole and improves the realism of the load distribution.

[0018] 3. It is suitable for various structural forms such as continuous charging, segmented charging, and axial air gap charging, and can be applied to various media such as rock, concrete, and soil, making it highly versatile.

[0019] 4. The system has a clear structure and is easy to operate. It can quickly output accurate load duration curves, providing reliable input parameters for blasting numerical simulation and engineering design, and significantly improving the accuracy and safety of blasting design.

[0020] In summary, the method of this invention obtains the peak value and time history characteristics of the blast load corresponding to the structural parameters of the charge by theoretically analyzing the propagation, reflection and transmission mechanism of the shock wave during the explosion of the charge section. The peak value of the blast load is used as the core control parameter to assign and correct the nodal load history curves at different spatial locations on the borehole wall. Thus, without relying on a unified empirical load assumption, a quantitative mapping relationship is established between the structural characteristics of the charge, such as the charge length, axial decoupling coefficient, number of air gaps and medium type, and the actual load distribution on the borehole wall. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Figure 1 This is a schematic diagram illustrating the theoretical derivation of the load curve of this invention.

[0023] Figure 2 This is a schematic diagram simulating different working conditions of the present invention.

[0024] Figure 3 This is a schematic diagram of the peak load on the borehole wall of the S1 of the present invention.

[0025] Figure 4 This is a schematic diagram of the peak load on the borehole wall of the S2 of the present invention.

[0026] Figure 5 This is a schematic diagram of the peak load on the S3 borehole wall of the present invention.

[0027] Figure 6 The diagram illustrates the application of load to the borehole wall according to the present invention. (a) shows the application of load according to the conventional concept, and (b) shows the application of load according to the innovative concept of the present invention.

[0028] Among them: 1. Explosive; 2. Air column; 3. Blocking; 4. Borehole wall; 5. Explosive load. Detailed Implementation To make the objectives, technical solutions, and advantages of this invention clearer, the embodiments of this invention will be described in detail below with reference to the examples. However, those skilled in the art will understand that the following examples are only for illustrating this invention and should not be regarded as limiting the scope of this invention.

[0029] Example 1: A method for determining the explosion load on the wall of an axially spaced air-filled explosive charging hole includes the following steps: Step 1: Determine the structural characteristic parameters of borehole blasting in the engineering application scenario; specifically, this includes: the performance parameters of the explosive itself, the geometric parameters of the borehole, the charge structure, and the type of the surrounding medium.

[0030] Step 2: Design a single-hole charging structure, control the axial decoupling coefficient, the number of axial air gaps, and the decoupling medium, and list the corresponding operating conditions; Step 3: Analysis based on explosion mechanics theory: The propagation, reflection and transmission laws of shock waves at different medium interfaces during the explosion of the charge section are theoretically derived, and finally the peak value of the blasting load and the characteristics of the load time history curve of the corresponding charge section under each charge condition are calculated.

[0031] To analyze the distribution mechanism of blast load under an axial air-spaced charge structure, a bottom-charge structure is taken as an example. The bottom of the borehole is considered to be of length... L e A continuous charge section, with a length set at the top. L a An air column, the orifice sealed by a plugging section. After the explosive detonates at the bottom, the shock wave waveform is as follows. Figure 1 As shown.

[0032] like Figure 1 As shown, after the explosive detonates at the bottom, it simultaneously generates a shock wave that travels to the right. SR Shockwave moving to the right SR Transmission and reflection occur at the explosive-air interface, forming reflected waves. FR 1 will move to the left and generate a reflected wave at the bottom of the hole. FR 2, while transmitted waves TR 1 will continue moving to the right; transmitted wave TR 1. Transmission and reflection will occur again at the explosive-blocking interface, where the reflected wave... FT R It will move to the left, transmitting waves TR 2 will continue to move to the right through the congestion.

[0033] After explosives detonate inside a borehole, the propagation of the shock wave may encounter different media. When the shock wave enters another medium from one medium, the nature of the reflected wave depends on the magnitude of the wave impedance of the two media themselves.

[0034] When the incident shock wave C Before the shock wave reaches the interface between the two media, the conservation of mass and momentum before and after the shock wave front indicates that: (1) In the formula: P The initial pressure of the medium on both sides of the interface. u The initial velocities of the media on both sides of the interface are... The density of the medium in front of the wavefront, The density of the medium behind the wavefront. The velocity of the shock wave front. The initial velocity of the medium in front of the wavefront. The initial velocity of the medium after the wavefront. The pressure behind the initial shock wave; Eliminate by equation (1) u A0 We can obtain: (2) In the formula: C 0 represents the velocity of the shock wave front.

[0035] Using the Hugoniot equation, the initial shock wave back pressure was further calculated as follows: (3) In the formula: and for A The empirical constant for shock compression in the medium can be obtained from this formula. B Impact pressure value of the region.

[0036] The solution can be obtained using equation (3). A The magnitude of the impact pressure in 1 can be determined by the physical quantities in the explosive medium based on the front-back relationship of the reflected rarefied wave front after the shock wave comes into contact with the interface between the two media. The front-back relationship of the shock wave front in the air medium can be determined based on the continuity condition of the interface.

[0037] Let the velocity of the particles in the region in front of the rarefied wavefront in the explosive medium be . u The velocity of the particles in the region behind the wavefront is u A1 The relationship between pressure before and after a sparse wave can be calculated from the relationship between particle velocities and state parameters in the regions before and after the wavefront. Therefore, the Murnaghan isentropic formula is used as an approximation for the solution. (4) In the formula, The pressure behind the sparse wavefront, For the pressure in front of the sparse wavefront, The adiabatic coefficient of the generated gas; The pressure behind the right-hand shock wave is: (5) In the formula: , These are the Grüneisen coefficients, representing the medium density of the explosive. The initial density of the No. 2 rock emulsion explosive is... The density of the medium in the backwave region after being disturbed by the shock wave.

[0038] Reflection and transmission occur at the explosive-air interface. Due to the large density difference between the explosive and air, the reflected rarefaction wave can be ignored. The pressure transmitted into the air column can be obtained by solving equation (6): (6) In the formula: The density of the air medium, The pressure transmitted into the air column. The adiabatic coefficient of the gas; For transmitted shock waves, the roughness of the borehole wall and the properties of the explosive affect their attenuation process, particularly in the air section. for: (7) In the formula: It is a proportionality constant. Let be the attenuation coefficient of the shock wave at this point. The length of the explosive section. The distance from the detonation point of the explosive. This represents the peak pressure of the air section.

[0039] Step 4: Use the peak load calculated in Step 3 as the key data for determining the load duration curves of each node on the borehole wall. Given the significant difference in peak loads between the explosive section and the air section, with the peak load of the explosive section being significantly higher than that of the air section, the two are processed and loaded separately during the load application process to more realistically simulate the propagation and evolution of the load in the borehole during the explosive explosion.

[0040] Example 2: The method of the present invention will be further described in detail below with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

[0041] Step 1: Using a large cylindrical granite sample with a diameter of 240 mm and a height of 300 mm, drill a borehole with a diameter of 10 mm and a length of 200 mm in its center. The plugging section is 80 mm long, and the charge section is 120 mm long, with the explosive having a density of 1.65 g / cm³. 3 , explosive speed D The speed is approximately 6900 m / s, the heat of explosion is approximately 4100 kJ / kg, the detonation pressure is approximately 19 GPa, and the explosion temperature can reach 2800 ℃.

[0042] Step 2: Set up 3 different charge structures, S1 to S3. S1, S2 and S3 are working conditions corresponding to different charge positions and number of segments when the axial decoupling coefficient is equal to 4.0. S1 and S2 are both single charge segments, but they are located at the bottom and top of the charge segment, respectively. S3 is a three-segment charge.

[0043] Step 3: Based on the different charge structures set in Step 2, to analyze the distribution and evolution mechanism of the blast load under the axial air gap charge structure, the above working conditions are derived. Considering the presence of a length of [missing information] at the bottom of the borehole... L e A continuous charge section, the upper part being a length of L a An air column, and a length of [missing information] is set at the orifice. L b The blocked section. After the explosive detonates at the bottom, the relationship between the shock wave propagation and the multi-interface interaction is as follows: Figure 1 As shown.

[0044] The shock wave propagating within a borehole from an explosive detonation may cross the boundaries of different media, and the difference in wave impedance between the media determines the nature and intensity of the transmitted and reflected waves. When an incident shock wave... C Before the particle reaches the interface, the relationship between the velocity and pressure of the particles before and after the interface can be obtained from the laws of conservation of mass and momentum as follows: (1) In the formula: P The initial pressure of the medium on both sides of the interface. u The initial velocities of the media on both sides of the interface are... The density of the medium in front of the wavefront, The density of the medium behind the wavefront. The velocity of the shock wave front. The initial velocity of the medium in front of the wavefront. The initial velocity of the medium after the wavefront. The pressure behind the initial shock wave; Eliminate by equation (1) u A0 We can obtain: (2) In the formula: C 0 represents the velocity of the shock wave front.

[0045] Using the Hugoniot equation, the initial shock wave back pressure was further calculated as follows: (3) In the formula: and for AThe empirical constant for shock compression in the medium can be obtained from this formula. B Impact pressure value of the region.

[0046] Since the peak pressure generated by the explosive segment depends only on the properties of the explosive itself, the duration of the effect... T Only related to the length of the explosive l Since the explosion of an explosive is a transient process, the explosive load of the explosive segment exhibits a "U" shape. The longer the explosive is, the longer the peak explosive load is.

[0047] Based on equation (3), the impact pressure in explosive medium A can be calculated. When the shock wave velocity C 0 is taken as 4200 m / s, the empirical constant for impact compression. Take 1.12, When the value is 0.91, the calculation is as follows: The value is 3.154 GPa.

[0048] When the shock wave reaches the explosive-air interface, it is necessary to further solve for the changing characteristics of the rarefied wave and the transmitted shock wave. Assume the particle velocity in the region before the rarefied wavefront is... Behind the wavefront is u A1 The sparse wave relation can then be approximated using the Murnaghan isentropic formula: (4) In the formula, The pressure behind the sparse wavefront, For the pressure in front of the sparse wavefront, The adiabatic coefficient of the generated gas; The pressure behind the right-hand shock wave is: (5) In the formula: , These are the Grüneisen coefficients, representing the medium density of the explosive. The initial density of the No. 2 rock emulsion explosive is... The density of the medium in the backwave region after being disturbed by the shock wave.

[0049] Reflection and transmission occur at the explosive-air interface. Due to the large density difference between the explosive and air, the reflected rarefaction wave can be ignored. The pressure transmitted into the air column can be obtained by solving equation (6): (6) In the formula: The density of the air medium, The pressure transmitted into the air column. The adiabatic coefficient of the gas; Axial decoupling coefficient K d Length of the charge section L e With the length of the explosive d e The ratio: (7) For transmitted shock waves, the roughness of the borehole wall and the properties of the explosive affect their attenuation process, particularly in the air section. P 3 is: (8) In the formula: It is a proportionality constant. Let be the attenuation coefficient of the shock wave at this point. The length of the explosive section. The distance from the detonation point of the explosive. This represents the peak pressure of the air section.

[0050] The load value of the air section calculated by formula (8) is combined with the load of the explosive section to form a complete borehole wall explosion load curve.

[0051] Taking S1 as an example, the explosive section is located at the bottom of the charging section, the axial decoupling coefficient is 4.0, the length of the explosive section is 0.03m, and the shock wave attenuation coefficient is... Take 1.12, the proportionality constant B is taken as 1.5, and take several... d 1. Calculate the magnitude of the loads respectively, as shown in Table 1. The peak load curves of S1 and S2 are as follows: Figure 3 , Figure 4 As shown.

[0052] Table 1. Relationship between peak load in the air section and distance from the explosion center.

[0053] For multi-stage explosive charges, such as in case S3, where the axial decoupling coefficient is 4.0 for all segments, the explosive charge is divided into corresponding segments, and the peak air load is calculated separately for each segment. Dividing the explosive charge into three parts results in a load superposition when two adjacent explosive segments are calculated to the middle of the air segment, creating a small "bulge." Combined with the peak load of each explosive segment, this can be plotted as follows: Figure 5 The corresponding peak load curve.

[0054] Step Four: The peak load calculated in Step Three is used as an important basis for determining the load duration curves of each node on the borehole wall. Since the peak load of the explosive section is much higher than that of the air section, they must be applied separately to better simulate the load propagation process of the explosive explosion. Compared with traditional methods, the application of loads is more efficient. Figure 6As shown.

[0055] In summary, the core advantage of the borehole wall load curve definition method proposed in this invention lies in its full consideration of the differentiated characteristics of the charge structure. Through rigorous theoretical derivation, it accurately obtains the peak parameters and time-varying process of the explosive load of the charge segment and deeply integrates them into the construction process of the borehole wall load curve. This technical solution can realistically reproduce the propagation characteristics and action mechanism of the explosive load inside the borehole, completely breaking through the limitations of the empirical and standardized load assumptions long used in the engineering field. It significantly improves the fit between numerical simulation results and actual blasting conditions, and significantly enhances the scientificity and credibility of simulation analysis. It provides key theoretical support and technical guarantee for the precise design, safety assessment, and performance optimization of geotechnical blasting engineering.

[0056] Example 3: This embodiment provides a system for determining the explosive load on the wall of an axially spaced air-gap charging hole, used to implement the method described above. The system includes: The parameter acquisition module is used to acquire the structural characteristic parameters of borehole blasting, including explosive performance parameters, borehole geometric parameters, charge structure parameters, and parameters of the surrounding medium of the blasting. The working condition design module is used to design multiple sets of single-hole charging structure working conditions based on the structural characteristic parameters. The working conditions are determined by adjusting the axial decoupling coefficient, the number of axial air gap segments, and the decoupling medium. The load calculation module is used to analyze the propagation, reflection and transmission of shock waves at different medium interfaces during the explosion of the charge section based on the theory of explosion mechanics, and to calculate the peak value of the blast load and the characteristics of the load time history curve of the charge section and the air section under various working conditions. The load application module is used to construct the load duration curve of each node of the borehole wall based on the peak value of the blasting load and the characteristics of the load time history curve. Combining the difference in the peak load of the charge section and the air section, the load duration curve is segmented and applied to the corresponding node.

[0057] Preferably, it also includes a data storage module for storing the structural characteristic parameters, working condition parameters, peak blast load, load time history curve characteristics, and load duration curve data. It also includes a result output module, which is used to output the load duration curves and blast load distribution results of each node of the borehole wall.

[0058] Preferably, the load calculation module incorporates an explosion mechanics theoretical calculation model, which integrates the mass conservation equation, momentum conservation equation, Hugoniot equation, and Murnaghan isentropic formula. The load application module has a built-in exponential decay curve generation unit, which is used to generate a corresponding load duration curve based on the peak value of the blasting load and the characteristics of the load time history curve.

[0059] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit of the invention and the scope of protection of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A method for determining the explosive load on the wall of an axially spaced air-gap charging hole, characterized in that, Includes the following steps: S1, Obtain the structural characteristic parameters of the borehole blasting, including explosive performance parameters, borehole geometric parameters, charge structure parameters, and blasting surrounding medium parameters; S2, Based on the structural characteristic parameters, design multiple sets of single-hole charging structure working conditions, which are determined by adjusting the axial decoupling coefficient, the number of axial air gap segments, and the decoupling medium; S3, based on the theory of explosion mechanics, analyzes the propagation, reflection and transmission laws of shock waves at different medium interfaces during the explosion of the charge section, and calculates the peak value of the blast load and the characteristics of the load time history curve of the charge section and the air section under each working condition. S4. Based on the peak value of the blasting load and the characteristics of the load time history curve, construct the load duration curve for each node of the borehole wall. Combined with the difference in peak load between the charge section and the air section, divide the load duration curve into segments and apply them to the corresponding nodes.

2. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 1, characterized in that, In step S1, the explosive performance parameters include explosive density, detonation velocity, heat of explosion, detonation pressure, and Grüneisen coefficient; the borehole geometric parameters include borehole diameter, length, and plugging length; the charge structure parameters include charge length, charge position, number of axial air gaps, and axial decoupling coefficient; and the blasting surrounding medium parameters include medium density, impact compression empirical constant, and wave impedance.

3. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 1, characterized in that, In step S2, the charge structure includes a continuous charge structure, a segmented charge structure, and a charge structure with axial air gaps; the uncoupled medium is air.

4. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 1, characterized in that, In step S3, when calculating the peak value of the blast load, the initial shock wave back pressure is derived by using the mass conservation equation, momentum conservation equation and Hugoniot equation, and the pressure relationship before and after the rarefaction wave is solved by combining the Murnaghan isentropic formula, and the transmitted shock wave pressure is determined by considering the difference in medium wave impedance.

5. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 1, characterized in that, In step S4, based on the significant difference in peak blast load between the charge section and the air section, load duration curves at different locations on the borehole wall are assigned values.

6. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 5, characterized in that, In step S4, the load duration curve of the borehole wall adopts an exponential decay curve, which is used to reflect the characteristics of the rising and decaying segments of the explosive load.

7. The method for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 5, characterized in that, The method is applicable to the analysis of blasting response in rock, concrete or soil media, and is used for the simulation of the duration of explosive blasting load in numerical simulation and theoretical calculation.

8. A system for determining the explosive load on the wall of an axially spaced air-filled charging hole, used to implement the method according to any one of claims 1 to 7, characterized in that, The system includes: The parameter acquisition module is used to acquire the structural characteristic parameters of borehole blasting, including explosive performance parameters, borehole geometric parameters, charge structure parameters, and parameters of the surrounding medium of the blasting. The working condition design module is used to design multiple sets of single-hole charging structure working conditions based on the structural characteristic parameters. The working conditions are determined by adjusting the axial decoupling coefficient, the number of axial air gap segments, and the decoupling medium. The load calculation module is used to analyze the propagation, reflection and transmission of shock waves at different medium interfaces during the explosion of the charge section based on the theory of explosion mechanics, and to calculate the peak value of the blast load and the characteristics of the load time history curve of the charge section and the air section under various working conditions. The load application module is used to construct the load duration curve of each node of the borehole wall based on the peak value of the blasting load and the characteristics of the load time history curve. Combining the difference in the peak load of the charge section and the air section, the load duration curve is segmented and applied to the corresponding node.

9. The system for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 8, characterized in that, It also includes a data storage module for storing the structural characteristic parameters, working condition parameters, peak blast load, load time history curve characteristics, and load duration curve data. It also includes a result output module, which is used to output the load duration curves and blast load distribution results of each node of the borehole wall.

10. The system for determining the explosive load on the wall of an axial air-spaced charging hole according to claim 8, characterized in that, The load calculation module incorporates an explosion mechanics theory calculation model, which integrates the mass conservation equation, momentum conservation equation, Hugoniot equation, and Murnaghan isentropic formula. The load application module has a built-in exponential decay curve generation unit, which is used to generate a corresponding load duration curve based on the peak value of the blasting load and the characteristics of the load time history curve.

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