Gas storage reservoir surrounding eye variable impedance charging method and system based on while-drilling parameter inversion

Abstract

The application provides a gas storage periphery eye variable resistance impedance charging method and system based on a while-drilling parameter inversion, and belongs to the technical field of underground engineering drilling and blasting construction, rock dynamics and intelligent construction. The method comprises the following steps: collecting while-drilling parameters of a rock drilling jumbo in real time and performing time-space reconstruction and denoising; establishing a modified mechanical specific energy model based on a percussion-rotary composite drilling mode; outputting a hardness curve in the hole depth direction through a comprehensive inversion model comprising a nonlinear mapping, a brittleness correction and a fracture reduction; matching a high-energy energy-gathering module, a variable-diameter centering decoupling module and a water-gas composite buffer isolation module according to the hardness curve, splicing a variable resistance charging kit and pushing the kit into a blast hole as a whole. By using the application, the problems of soft rock overbreak, hard rock underbreak caused by the unified charging mode in the prior art and the low prediction accuracy caused by the lack of rigorous physical derivation of the existing while-drilling data inversion model can be solved.

Description

Technical Field

[0001] This invention relates to the fields of underground engineering drilling and blasting construction, rock dynamics and intelligent construction technology, and in particular to a method and system for variable impedance charging of explosives around a gas storage facility based on drilling parameter inversion. Background Technology

[0002] In the construction of underground projects such as underground gas storage facilities, deep-buried extra-long tunnels, and large underground water-sealed rock cavern oil depots, the drill-and-blast method is widely used due to its strong adaptability and controllable cost. The blasting quality of the peripheral holes (outline holes) directly determines the smoothness of the excavation outline and the integrity of the surrounding rock. Especially in underground gas storage projects, which need to withstand extremely high internal gas pressure, the standards for excavation outline forming accuracy, surrounding rock damage control, and seepage prevention performance are far more stringent than those for ordinary tunnels. How to achieve refined smooth blasting of peripheral holes under heterogeneous lithology has become a key technical challenge that urgently needs to be overcome in this field.

[0003] In existing technologies, the charge design for smooth blasting is typically based on the surrounding rock grade determined by the preliminary macro-geological survey report. A uniform charge structure is used for the perimeter holes of the same excavation section and even the entire construction area, namely a fixed linear charge density, uniform PVC pipe air gaps, and a fixed decoupling coefficient. Regarding data utilization, although intelligent drilling rigs have become increasingly common in construction in recent years, and their measurement-while-drilling (MWD) data has been preliminarily used for geological identification, most existing inversion algorithms remain at the stage of statistical fitting based on empirical formulas, lacking rigorous physical derivation from the perspective of rock fragmentation energy conservation, and have insufficient generalization ability under different geological conditions. In the charge implementation stage, even with information on the lithological distribution within the borehole, existing charge structures still mainly rely on on-site manual cutting and binding of single-specification explosive cartridges, failing to achieve continuous and precise impedance matching of explosive energy for different lithological sections along the borehole depth.

[0004] The aforementioned existing technical solutions have the following prominent problems: First, the uniform charging mode cannot adapt to the strong heterogeneity of natural rock masses in the borehole depth direction. In the same borehole, soft rock sections are prone to severe over-excavation and damage to the surrounding rock due to relatively excessive charge, while hard rock sections suffer from under-excavation and root retention due to insufficient energy. The coexistence of these two issues seriously affects the quality of the excavation profile and the stability of the surrounding rock. Second, the existing MWD inversion model does not consider the dominant contribution of impact work in the "impact-rotation" composite drilling mode of the drilling rig, nor does it systematically incorporate correction factors for rock brittleness and fracture water pressure. This results in limited accuracy in predicting the strength of the rock mass within the borehole, making it difficult to provide reliable segment-by-segment hardness data for charge design. Third, the traditional single-cartridge charging method lacks structural control over the directionality of the explosive shock wave, failing to achieve tangential energy focusing and lateral buffering for directional energy distribution, and thus cannot fundamentally solve the problem of excessive damage to weak surrounding rock. Summary of the Invention

[0005] This invention provides a method and system for variable impedance charging of explosives around a gas storage reservoir based on drilling parameter inversion. This method addresses the problems of over-excavation in soft rock and under-excavation in hard rock caused by the uniform charging mode in existing technologies, as well as the low prediction accuracy resulting from the lack of rigorous physical derivation in existing drilling data inversion models. The technical solution is as follows: Firstly, a method for loading explosives around a gas storage facility using variable impedance charging based on drilling parameter inversion includes the following steps: Step 1: On the hydraulic circuit of the rock drilling rig, real-time sampling rate of not less than 50Hz is used to collect drilling parameters during the peripheral hole drilling process. The drilling parameters include feed pressure. Rotational pressure Impact pressure Drilling speed Rotation speed and flushing water pressure The collected drilling parameters are based on time. The sequence data is spatiotemporally reconstructed, and the drilling parameters are converted into parameters based on the surrounding hole depth. The spatial distribution data is processed and denoised to obtain a smooth spatial sequence data matrix; Step 2: Based on the classical mechanical energy specific model, introduce the impact energy term to establish a modified mechanical energy specific model suitable for the impact-rotation composite drilling mode. The real-time calculation model is used, and the hydraulic system parameters of the rock drilling rig are used to replace the mechanical force at the bottom of the surrounding holes with equivalent values ​​to obtain the corrected mechanical energy distribution in the hole depth direction. Step 3: Based on the corrected mechanical specific energy distribution, the uniaxial compressive strength of the rock mass is established through nonlinear fundamental mapping, brittleness and cutting depth correction, and joint and fracture reduction correction. The comprehensive inversion model outputs a continuous hardness curve in the hole depth direction; Step 4: Based on the continuous hardness curve, divide the charge unit along the hole depth direction. According to the UCS value of each charge unit, match the corresponding charge module from the preset module types. The module types include at least a variety of functional modules suitable for different rock mass hardness ranges. Step 5: Generate a charging instruction containing the module type and arrangement order of each charging unit, assemble the modules in sequence to form a charging kit with the same depth as the hole, and push the whole kit into the borehole to complete the charging.

[0006] Optionally, in step one, the aperture depth of the spatiotemporal reconstruction The calculation formula is: ; In the formula, τ is the integral time variable, and the denoising process adopts the wavelet threshold denoising algorithm to remove abnormal high-frequency jump signals caused by drill pipe connection and local stuck drill.

[0007] Optionally, in step two, the corrected mechanical specific energy... The real-time computing model is as follows: ; In the formula, To improve the system's energy decay coefficient, The energy attenuation coefficient of the impact system. For the depth of the hole The pressure to advance, To increase the effective area of ​​the piston in the propulsion cylinder, For return oil pressure, This represents the effective area of ​​the piston on the oil return side. The cross-sectional area of ​​the drill bit. For a single impact, For the impact frequency, For drilling speed, For rotational speed, This refers to the rotational torque.

[0008] Optionally, in step three, the uniaxial compressive strength of the rock mass... The comprehensive inversion model is as follows: ; In the formula, For nonlinear fundamental mapping coefficients, This is the brittleness correction factor. This is a brittleness correction index. This is the fracture reduction factor. These are constant terms, all of which are site-specific calibration coefficients obtained through joint training of on-site rock mechanics core sampling tests and machine learning. For the depth of the hole Corrected mechanical specific energy at the location, Measured per revolution. This represents the instantaneous pressure drop of the flushing water pressure.

[0009] Optionally, step four includes: When the UCS of the charging unit is ≥80MPa, a high-energy focusing module is allocated; the outer shell of the high-energy focusing module is made of high-density polyethylene, and the inside is filled with high-explosive emulsion explosive. The coupling coefficient between the outer diameter and the borehole diameter is 0.9 to 1.0. V-shaped focusing grooves with an included angle of 80° to 100° are opened on both sides of the outer shell along the axial direction. When the UCS of the charging unit is greater than or equal to 30MPa and less than 80MPa, a variable diameter centering decoupled module is allocated; the center of the variable diameter centering decoupled module is a standard diameter cartridge, and the outside is covered by a thin-walled PVC pipe 22. The outer wall of the thin-walled PVC pipe 22 is evenly distributed with 4 to 6 variable diameter self-locking centering blades, and the decoupling coefficient is 1.5 to 2.0. When the UCS of the charging unit is less than 30 MPa, a water-air composite buffer isolation module is allocated. The water-air composite buffer isolation module adopts an asymmetrical eccentric structure. A high-impedance rigid reflector is set on the side closer to the excavation center, and a porous aerogel-polyurethane composite energy absorption layer with a thickness of 10-15 mm is set on the side closer to the retained surrounding rock.

[0010] Optionally, the variable-diameter self-locking centering wing is made of shape memory alloy or elastic plastic, and automatically expands to fit the borehole wall after being pushed into the borehole, so that the propellant cartridge remains in a centered position inside the borehole.

[0011] Optionally, the end of the charge kit of the water-air composite buffer isolation module is provided with a direction indicator. In step five, when pushing into the borehole, the direction indicator is used to make one side of the composite energy-absorbing layer face the direction of the surrounding rock to be retained.

[0012] Secondly, a variable impedance charging system for a gas storage perimeter eye based on drilling parameter inversion, used to implement the aforementioned variable impedance charging method for a gas storage perimeter eye based on drilling parameter inversion, is characterized by further comprising: The drilling data acquisition module is installed on the hydraulic circuit of the drilling rig. It is used to collect the propulsion pressure, rotation pressure, impact pressure, drilling speed, rotation speed and flushing water pressure in real time during the drilling process of the peripheral hole at a sampling rate of not less than 50Hz. The time-based sequence data is converted into a spatial sequence data matrix based on hole depth after spatiotemporal reconstruction and noise reduction. An edge computing terminal, communicatively connected to the drilling data acquisition module, receives the spatial sequence data matrix, calculates the corrected mechanical energy distribution along the hole depth direction based on a corrected mechanical energy model of the impact-rotation composite drilling mode, and outputs a continuous hardness curve along the hole depth direction through a comprehensive inversion model that includes nonlinear basic mapping, brittleness and cutting depth correction, and joint and fracture reduction correction. Then, based on the continuous hardness curve, a one-hole-one-policy charging instruction is generated; The modular variable impedance continuous charge kit is configured according to the charge instructions and includes multiple standardized charge modules that are sequentially spliced ​​together by male and female end clips. The standardized charge modules include at least two of the following: high-energy focusing modules suitable for different rock mass hardness ranges, variable diameter centering decoupled modules, and water-air composite buffer isolation modules.

[0013] Optionally, the drilling data acquisition module includes a high-frequency pressure sensor and a displacement sensor installed on the hydraulic circuit of the drilling rig; the edge computing terminal has a built-in decision matrix, and the decision matrix has the following rules: when the UCS of the charging unit is ≥80MPa, the high-energy focusing module is allocated; when the UCS of the charging unit is greater than or equal to 30MPa and less than 80MPa, the variable diameter centering decoupled module is allocated; and when the UCS of the charging unit is <30MPa, the water-air composite buffer isolation module is allocated.

[0014] Optionally, the edge computing terminal is also used to generate a module assembly BOM list and output a 3D assembly instruction diagram; the calibration coefficients in the integrated inversion model are obtained by joint training of on-site rock mechanics core sampling test and support vector regression, and the spatial resolution of the continuous hardness curve is to output a UCS value every 0.1m along the hole depth direction.

[0015] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: This invention provides a method and system for variable impedance charging of gas storage perimeter boreholes based on drilling parameter inversion. It breaks away from the traditional black-box approach of purely empirical data fitting, rigorously deriving a composite drilling model from classical mechanical energy theory, and fully considering the reduction effects of rock brittleness and fracture water pressure. This model can accurately identify the boundary locations of weak interlayers within the borehole and exhibits strong adaptability and generalization ability under various complex and variable geological conditions. The accompanying modular variable impedance charging kit achieves a high degree of consistency between the explosive energy and rock impedance in spatial distribution, which can greatly curb over-excavation in soft rock sections and effectively eliminate under-excavation risks in hard rock sections, comprehensively and significantly improving the smoothness and forming quality of the tunnel excavation profile. The innovative buffer isolation module breaks the traditional physical characteristics of omnidirectional radiation of explosive energy. In weak and fractured zones, through the plastic deformation of energy-absorbing materials and the reflection effect of rigid media, it significantly weakens the destructive shock wave directed at the surrounding rock, significantly improving the porosity retention rate of the surrounding holes. This provides a solid guarantee for underground engineering projects with extremely high requirements for seepage prevention, such as underground gas storage facilities. Differentiated charging instructions are automatically generated by edge computing terminals, and standardized charging modules are plug-and-play, completely overturning the traditional cumbersome and highly experience-dependent charging mode. This significantly shortens the charging operation cycle, reduces the labor intensity of on-site personnel, and powerfully promotes the transformation and upgrading of traditional drill-and-blast construction towards digitalization, intelligence, and industrialization. It can effectively solve the problems of over-excavation in soft rock and under-excavation in hard rock caused by the uniform charging mode in existing technologies, as well as the low prediction accuracy caused by the lack of rigorous physical derivation in existing drilling data inversion models. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0017] Figure 1 This is a flowchart of the method provided in an embodiment of the present invention; Figure 2 This is a schematic cross-sectional view of the high-energy focusing module provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the high-energy focusing module assembly provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the variable diameter centering decoupled module provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the assembly of the variable diameter centering non-coupled module provided in an embodiment of the present invention; Figure 6 This is provided by the embodiments of the present invention. Figure 5 Enlarged view of point A; Figure 7 This is a schematic cross-sectional view of the water-air composite buffer isolation module provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the assembly of the water-air composite buffer isolation module provided in an embodiment of the present invention.

[0018] In the diagram: 1-High-energy focusing module; 11-V-shaped energy focusing trough; 2-Variable diameter centering non-coupled module; 21-Standard diameter cartridge; 22-Thin-walled PVC pipe; 23-Variable diameter self-locking centering wing; 3-Water-air composite buffer isolation module; 31-Rigid reflector; 32-Composite energy absorption layer; 33-Direction indicator. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0020] This embodiment provides a method for loading explosives into the periphery of a gas storage facility based on drilling parameter inversion, such as... Figure 1 As shown, it includes the following steps: S1: High-frequency acquisition and spatiotemporal sequence reconstruction of multi-source drilling parameters (MWD).

[0021] High-frequency pressure and displacement sensors are installed on the hydraulic circuit of the intelligent rock drilling rig to collect real-time drilling data during the peripheral hole drilling process at a sampling rate of no less than 50Hz. The collected parameters include: feed pressure. Rotational pressure Impact pressure Drilling speed Rotation speed and flushing water pressure Because the sensor collects data based on time... The sequence data, while the charge structure needs to be based on the hole depth space. The distribution data. The system first performs spatiotemporal reconstruction, hole depth The calculation formula is: ; Subsequently, a wavelet threshold denoising algorithm was used to remove abnormal high-frequency jump signals caused by drill pipe connection and local stuck drill, and a smooth spatial sequence data matrix was obtained.

[0022] Specifically, the wavelet thresholding denoising process is as follows: The db4 orthogonal wavelet from the Daubechies series is selected as the analysis mother function, and a 5-level multi-resolution decomposition is performed on the hole depth spatial sequence of each drilling parameter. For threshold selection, the general threshold criterion proposed by Donoho is adopted, where the threshold λ is equal to the product of the noise standard deviation estimate and the square root of the logarithm of the signal length. The noise standard deviation is robustly estimated by dividing the absolute median difference of the highest frequency detail coefficients by 0.6745. Soft thresholding is applied to the detail coefficients at each level, i.e., coefficients with absolute values ​​less than the threshold are set to zero, and coefficients with absolute values ​​greater than the threshold are reduced in the direction of zero. After processing, the signal is reconstructed using the low-frequency approximation coefficients and the corrected detail coefficients at each level, thus obtaining the denoised smooth spatial sequence. For transient impact signals caused by drill pipe connection, since their time domain width is extremely narrow and their amplitude is far greater than that of normal drilling signals, preprocessing is performed by sliding window detection and neighborhood median replacement before wavelet denoising. Data points that deviate from the window median by more than 3 times the window standard deviation are replaced with local medians, and then the above wavelet denoising process is performed.

[0023] S2: Derivation of the Modified Mechanical Specific Energy (MSE) model based on energy conservation.

[0024] The core inversion logic of this invention is based on the law of conservation of energy in rock fracturing. Teale proposed the classic concept of mechanical specific energy (MSE), which is the mechanical work consumed in fracturing a unit volume of rock. For traditional pure rotary drilling (such as roller cone drill bits), the work done consists of two parts: the work done by the propulsion force and the work done by the rotational torque. The classic formula is: ; In the formula, For propulsion, For rotational torque, The cross-sectional area of ​​the drill bit. For rotational speed, This represents the drilling speed.

[0025] Correction for Top Hammer Impact Work: The intelligent rock drilling rig employs a "top hammer impact-rotation" composite drilling mode. In hard rock, over 70% of the rock-breaking energy comes from the low-frequency, high-energy impact of the hydraulic rock drill, rather than simple rotary cutting. Therefore, the classic Teale formula severely underestimates rock-breaking energy. This invention, based on this, introduces an impact energy term. : ; In the formula, For a single impact, The frequency is the impact frequency.

[0026] By incorporating the impact energy term into the classical formula, we obtain the basic model of the specific energy of composite drilling machinery: ; Equivalent conversion of hydraulic parameters to mechanical parameters: Since the mechanical force at the bottom of the hole cannot be directly measured on site. and This invention utilizes the hydraulic system parameters of a rock drilling rig for equivalent substitution. (Thrust force) Determined by the pressure difference between the inlet and outlet oil of the propulsion cylinder: ; In the formula, , For the effective area of ​​the piston, This refers to the return oil pressure.

[0027] When the hydraulic rock drill of a rock drilling rig is working, the hydraulic piston reciprocates at a certain frequency to strike the drill bit, converting hydraulic energy into impact mechanical energy. The energy of a single impact... The structural parameters and impact pressure of the rock drill's impact piston can be used to determine the impact parameters. Jointly determined: The effective pressure-bearing cross-sectional area of ​​the rock drill impact piston is known to be... The effective stroke of the impact piston is Therefore, the energy of a single impact is approximately equal to the product of the impact pressure, the piston's bearing cross-sectional area, and the effective stroke, i.e. ≈ · · The above. and These are inherent structural parameters of the rock drill, which can be found in the technical manual provided by the equipment manufacturer. Impact frequency The relationship between impact pressure and frequency is determined by the hydraulic oscillation characteristics of the rock drill. Within the constant power adjustment range, the impact frequency decreases with increasing impact pressure and increases with increasing hydraulic oil flow. In actual construction, an accelerometer can be installed on the rock drill housing. By performing fast Fourier spectrum analysis on the vibration signal, the dominant frequency component can be extracted, which is the real-time impact frequency. Alternatively, the impact pressure-impact frequency calibration curve provided by the rock drill manufacturer can be used for table lookup and interpolation.

[0028] The rotary motor of the rock drilling rig converts hydraulic energy into rotational mechanical energy. Rotational torque. T With rotational pressure The relationship between the calculations is determined by the displacement parameter of the rotary motor: Given that the displacement per revolution of the rotary motor is... The mechanical efficiency of the rotary motor is The slewing torque at the bottom of the hole is approximately equal to the product of the slewing pressure, the displacement per revolution, and the mechanical efficiency, divided by 2π. This relationship allows us to utilize the real-time collected slewing pressure. Calculate the slewing torque T Rotary motor displacement and mechanical efficiency These are also inherent parameters of the equipment, obtained from the hydraulic system design documents of the rock drilling rig.

[0029] Finally, the corrected mechanical specific energy suitable for rock drilling rigs was derived. Real-time calculation formula: ; In the formula, , These are the energy attenuation coefficients of the propulsion system and the impact system during the drill pipe transmission process (usually taken as 0.6 to 0.85, decreasing with increasing hole depth).

[0030] The on-site calibration method for the energy attenuation coefficient is as follows: Before or at the initial stage of construction, select a test section with homogeneous rock and known compressive strength, and perform standard drilling in this section using a drilling rig. Temporarily install a bottom-hole mechanical sensing device at the connection between the drill rod and the drill bit to directly measure the actual thrust and impact energy at the bottom of the hole; simultaneously record the thrust and impact pressure at the hydraulic circuit end. The ratio of the measured thrust at the bottom of the hole to the calculated thrust at the hydraulic end is taken as... The initial calibration value is the ratio of the measured impact energy at the bottom of the hole to the calculated impact energy at the hydraulic end. The initial calibration value. Repeat the above measurements at different hole depths to obtain the initial calibration value. and The decay law with hole depth is generally fitted using a linear or exponential decreasing function. For the same type of drilling rig and the same type of drill pipe assembly, the calibration results are applicable under the same engineering conditions, and only need to be recalibrated when the drill pipe specification or rig model is changed.

[0031] S3: Derivation of the comprehensive inversion model for uniaxial compressive strength (UCS) of rock mass.

[0032] Under ideal brittle fracture conditions, mechanical specific energy Numerically, it should be approximately equal to the uniaxial compressive strength (UCS) of the rock. However, in actual drilling, there is energy dissipation due to repeated cutting of rock powder and frictional heating of the drill bit. This invention establishes a final UCS inversion mapping model by introducing two correction terms: drilling depth and fracture water pressure response.

[0033] Nonlinear fundamental mapping: As rock hardness increases, rock-breaking efficiency decreases exponentially; therefore, a logarithmic relationship is used to describe the fundamental mapping. ; Brittleness and Depth of Cut Correction: Introducing Progress Per Revolution (PR), i.e. The larger this ratio, the more easily the rock breaks into large chunks (high brittleness, low hardness). A correction term is introduced. .

[0034] Joint and fracture reduction correction: Natural rock masses contain fractures, and flushing water leaks as it passes through these fracture zones, leading to reduced flushing water pressure. Instantaneous voltage drop The greater the pressure drop, the more fractured the rock mass and the lower its macroscopic strength. A reduction term is introduced. .

[0035] Instantaneous pressure drop of flushing water The extraction method is as follows: First, the noise-reduced flushing water pressure signal is processed. Establish a baseline pressure envelope. Using the steady-state flushing water pressure of the intact rock section at the borehole orifice as a reference value, establish a low-frequency trend line along the borehole depth as the theoretical baseline pressure. This trend line can be obtained by... The data is obtained by using a large window (the number of data points corresponding to a window width of not less than 0.5m) moving average filtering. Instantaneous pressure drop is defined as the difference between the reference pressure and the measured pressure, i.e. = - When the difference is negative (the measured water pressure is higher than the baseline), take... =0. This extraction method can effectively identify the local water pressure drop caused by flushing water leaking into the surrounding rock fissures due to the drill bit crossing the fracture zone. The pressure drop amplitude is positively correlated with the degree of fracture development and opening.

[0036] Based on the above physical mechanisms, the final formula for calculating rock mass hardness inversion is derived: ; In the formula, , , , , These are site-specific calibration coefficients obtained through joint training using prior field rock mechanics coring tests and machine learning (such as Support Vector Regression, SVR). Using this formula, the system can output continuous hardness curves for every 0.1-meter segment along the borehole depth in real time.

[0037] The specific implementation process of joint training for calibration coefficients is as follows: In the pilot test phase before formal construction, several core drilling holes are set up along the proposed construction area. The number of core drilling holes is no less than 3, and the total core length is no less than 15m. The core drilling locations should cover as many typical rock types in the construction area as possible. The extracted rock cores are recorded and strength tested at 0.1m intervals. A point load tester is used for rapid on-site testing and the results are converted to uniaxial compressive strength. At the same time, representative rock core samples are selected and sent to the laboratory for standard uniaxial compression tests to verify the accuracy of the point load conversion. Subsequently, near the same core drilling locations, the same type of drilling rig used in the construction is used for accompanying drilling. Complete drilling parameters are collected, and the corrected mechanical specific energy at each depth is calculated according to steps S1 and S2 above. Intermediate values ​​such as advance per revolution and instantaneous pressure drop of flushing water were used. The UCS value obtained from core tests was used as the target variable, and the logarithmic value of the corrected mechanical specific energy at the corresponding depth, the power function value of advance per revolution, and the instantaneous pressure drop of flushing water were used as input feature vectors to construct a training sample set. Support vector regression was used for model training, with the radial basis function kernel function selected. The penalty parameter C0 and the kernel width parameter σ were determined through a combination of 5-fold cross-validation and grid search. The regression coefficients output after training correspond to α, β, γ, δ, and C in the inversion formula. During subsequent construction, the calibration coefficients were incrementally updated using newly obtained core data every 50m of cumulative advance or when significant geological changes occurred, to maintain the model's continued applicability.

[0038] S4: Innovative charge structure design – modular variable impedance continuous charge kit.

[0039] Each standardized propellant module is joined using an axially pluggable quick-connect coupling. Each module has a tenon end and a recessed end. The tenon end is a cylindrical protrusion with an outer diameter slightly smaller than the inner diameter of the module's outer shell, and its outer wall has 2-4 elastic claws evenly spaced circumferentially. The recessed end is a corresponding cylindrical concave cavity with an annular locking groove on its wall to engage with the elastic claws. During assembly, the tenon end of one module is inserted into the recessed end of the adjacent module. The elastic claws are compressed inwards, passing through the cavity opening and automatically ejecting to engage with the annular locking groove, forming an axial lock. This connection method requires no tools, and the assembly time for a single connector is no more than 3 seconds. After assembly, it can withstand an axial pull-out force of no less than 50N, ensuring that the entire propellant assembly does not disintegrate during insertion into the borehole. After assembly, the end faces of each module are tightly joined, with a detonation gap at the joint not exceeding 2mm, ensuring reliable propagation of the detonation wave throughout the entire propellant assembly.

[0040] To transform the inverse hardness curve into the actual physical structure of the propellant charge, this invention innovatively designs a modular variable impedance continuous charge kit. This kit is composed of various standardized modules with different functions, spliced ​​together by male and female snap-fits at the ends, with the total length matching the hole depth. Module types include: Extremely hard rock section (UCS≥80MPa) - High-energy focusing module 1 (e.g.) Figure 2 and Figure 3 (as shown) Figure 2 The two circular rings form the module's outer shell, which is made of high-density polyethylene (HDPE) and filled with high-velocity emulsion explosive. The coupling coefficient between the outer diameter and the borehole diameter is close to 1.0 (fully coupled). Its innovation lies in the V-shaped shaped charge grooves 11 with an included angle of 90 degrees formed along the axial direction on both sides of the outer shell. Upon detonation, the high-temperature, high-pressure metal or plastic jet generated by the shaped charge effect preferentially cuts guide cracks in the hard borehole wall, overcoming the tensile strength of high-resistivity rock. The detonation velocity of the high-velocity emulsion explosive is not less than 4500 m / s, and the charge density is 1.10–1.25 g / cm³. 3 The sympathetic detonation distance is no more than 5cm. The purpose of selecting a high-velocity explosive is to generate a sufficiently high peak shock wave pressure in the extremely hard rock section to overcome the dynamic compressive strength of the high-strength rock. Combined with the directional jet generated by the V-shaped energy channel 11, an initial guide crack is formed in a predetermined direction on the borehole wall. During the subsequent gas expansion stage, this crack further propagates, ultimately achieving a through crack along the direction connecting the surrounding boreholes, forming a smooth excavation profile. For example... Figure 3 As shown, the high-energy focusing module 1 is connected to other modules by male and female snap-fit ​​joints, which can be assembled by robots or operators using a modular snap-fit ​​method.

[0041] Medium-hard rock section (30MPa≤UCS<80MPa) — Variable diameter centering uncoupled module 2 (e.g.) Figure 4 , Figure 5 and Figure 6 As shown): The module's center contains a standard diameter propellant cartridge 21 (e.g., 25mm or 32mm in diameter), encased in a thin-walled PVC tube. Four to six variable-diameter self-locking centering fins 23 are evenly distributed on the outer wall of the thin-walled PVC tube. These fins are made of shape memory alloy or elastic plastic and automatically expand to fit the borehole wall after being pushed in, ensuring the propellant cartridge remains perfectly centered within the borehole. Figure 5 As shown, the outermost left and right sides are the blast holes. The variable diameter centering decoupling module 2 is radially decoupled from the blast holes. Through precise radial decoupling effect (decoupling coefficient 1.5~2.0), the peak value of the shock wave is reduced, achieving standard smooth blasting. Figure 4 As shown, the top and bottom of the variable diameter centering non-coupled module 2 are a universal male snap-fit ​​and a female snap-fit, respectively, so as to be spliced ​​with other modules.

[0042] Weak interlayer section (UCS < 30MPa) – Water-air composite buffer isolation module 3 (e.g.) Figure 7 and Figure 8 (As shown): This module is specifically designed for over-excavation in soft rock. It employs an asymmetrical eccentric structure, with a high-resistance rigid reflector plate 31 on the side closer to the tunnel excavation center, and a 10-15mm thick composite energy-absorbing layer 32 of porous aerogel and polyurethane on the side closer to the remaining surrounding rock. Extremely low detonation velocity explosives are filled between the rigid reflector plate 31 and the composite energy-absorbing layer 32, with an air gap provided. The extremely low detonation velocity explosives used are modified ammonium oil-based micro-detonation velocity water-containing explosives or powdered emulsion low-detonation velocity agents, with a detonation velocity range controlled between 1800 and 2500 m / s and a density of 0.8-1.0 g / cm³. 3The low detonation velocity significantly reduces the peak detonation wave pressure compared to conventional emulsion explosives. Combined with the expansion and buffering effect of the air gap layer, it effectively limits the impact load acting on weak surrounding rock below its dynamic failure threshold. The thickness of the reserved air gap is 5–10 mm, maintained by annular partition ribs on the inner wall of the module. The preparation process of the porous aerogel-polyurethane composite energy-absorbing layer is as follows: First, silica aerogel particles (particle size 0.5–2 mm, porosity not less than 90%) are uniformly incorporated into the two-component polyurethane prepolymer at a mass ratio of 30%–40%. After thorough mixing, the mixture is injected into a pre-designed arc-shaped semi-cylindrical mold. The inner wall of the mold is pre-coated with a release agent, and the radius of curvature of the mold is consistent with the radius of the borehole. The mold is allowed to stand at room temperature for 4–6 hours to foam and cure. After demolding, it is cut to a standard size equal to the length of the module. The cured composite energy absorber exhibits a semi-rigid porous structure, with aerogel particles uniformly dispersed within a polyurethane foam matrix. The overall porosity is no less than 75%, and the compressive deformation can reach over 60% of its thickness. When subjected to an explosive shock wave, it dissipates a significant amount of impact energy through plastic buckling of the pore walls and progressive fragmentation of the aerogel skeleton. The prepared composite energy absorber is bonded to the inner wall of the surrounding rock side of the module shell using structural adhesive. When the explosive shock wave reaches the surrounding rock side, the micropores of the energy-absorbing layer undergo plastic collapse, absorbing over 70% of the shock wave energy. The peak stress wave transmitted into the soft rock is forcibly attenuated below its dynamic compressive strength, thus achieving ultimate protection for the weak surrounding rock. Figure 8 As shown, the water-air composite buffer isolation module 3 is also spliced ​​with other modules using male and female snap fasteners. A direction indicator 33 is set at the end of the kit of the water-air composite buffer isolation module 3 so that the direction indicator 33 faces the side of the retained surrounding rock.

[0043] S5: One-hole-one-policy charge command generation and adaptive assembly.

[0044] After the rock drilling rig completes a single hole, the onboard edge computing terminal immediately uses the data retrieved from the S3 database. The curve is divided into charging units every 0.5 meters along the borehole depth. The unit length is 0.5m, chosen based on the following considerations: Firstly, the standard charging module's individual length is set to 0.4-0.5m, matching the charging unit length and facilitating configuration of one module per unit; secondly, the 0.5m division precision is far less than the typical thickness of weak interlayers in underground engineering (usually 1-3m), sufficient to capture most engineering-significant lithological change interfaces. Given that the integrated inversion model outputs a UCS value every 0.1m, each 0.5m charging unit contains 5 UCS data points. The system takes the arithmetic mean of these 5 data points as the representative UCS value for that charging unit, and uses this as the basis for module matching decisions. When the difference in the mean UCS values ​​of two adjacent charging units exceeds 20MPa, the system automatically inserts a transition segment marker at their interface, reminding construction personnel that the module interface is located at a lithological abrupt change zone.

[0045] The system has a built-in decision matrix: if the unit's UCS ≥ 80, allocate high-energy focusing module 1; if 30 ≤ UCS < 80, allocate variable-diameter centering decoupled module 2; if UCS < 30, allocate water-air composite buffer isolation module 3.

[0046] The system automatically generates a module assembly BOM list for the borehole (e.g., 0-1m from the bottom of the borehole is high-energy focusing module 1, 1-2m is water-air composite buffer isolation module 3, and 2-3m is variable-diameter centering decoupled module 2). On-site loading robots or construction personnel connect the modules according to the list, like assembling building blocks, and push the entire assembly into the borehole. During insertion, the direction indicator 33 at the end of the assembly ensures that the energy-absorbing side of all water-air composite buffer isolation modules 3 is strictly facing the surrounding rock.

[0047] The specific implementation of the directional indicator is as follows: On the outer end face of the water-air composite buffer isolation module, a fluorescent strip with a width of not less than 5mm is set in the radial direction along the side where the composite energy-absorbing layer is located. This strip extends from the module end face to the side of the outer shell for about 20mm, and is clearly visible in the low-light environment common in tunnel construction. At the same time, a corresponding directional mark is also set on the module end face of the outermost end (orifice end) of the explosive charge kit. Before pushing the blast hole, the construction personnel only need to align the directional mark at the orifice end with the direction of the retained surrounding rock. Since each module has a fixed circumferential positioning relationship when spliced ​​by the tenon end and the groove end (the tenon end has a positioning rib, and the groove end has a corresponding positioning guide groove, and the circumferential angle of each module is uniquely determined after the two are combined), as long as the orifice end direction is correct, the energy-absorbing layer side of all water-air composite buffer isolation modules in the kit will automatically face the side of the retained surrounding rock, without the need to calibrate the direction of each module individually.

[0048] The following is a specific example: In the excavation of the main cavern of an underground natural gas storage facility, the excavation section is 18 meters wide and 14 meters high. The geological conditions are extremely complex, mainly consisting of Permian limestone, but frequently interbedded with weak layers of argillaceous shale and fault breccia. In the early stages, conventional smooth blasting was used, but severe over-excavation frequently occurred in the soft rock section at the arch crown, with the maximum over-excavation depth reaching 65 cm.

[0049] When drilling the 22nd peripheral hole (designed depth 3.0 meters, diameter 42 mm) in the arch using a three-arm intelligent rock drilling rig, the onboard system collected MWD data at a frequency of 50 Hz. When drilling reached the 1.2-2.2 meter range, the system monitored the propulsion pressure. The flushing water pressure dropped sharply from 12 MPa to 5 MPa. A momentary pressure drop of 0.3 MPa occurred (indicating water leakage due to fractures), and the drilling speed... The speed surged from 1.5 m / min to 3.2 m / min. The edge computing terminal invoked the modified mechanical specific energy model and comprehensive inversion formula derived in this invention: ; Substitute the pre-defined parameters of the site (such as...) , Real-time calculations show that the average UCS in the 0–1.2m section is 85 MPa (extremely hard limestone); the average UCS in the 1.2–2.2m section is only 22 MPa (muddy shale interlayer) due to a sharp drop in mechanical specific energy and water pressure reduction; and the average UCS in the 2.2–3.0m section is 78 MPa (medium-hard limestone).

[0050] The system then generates a one-hole-one-policy loading instruction: Bottom section of the hole (2.2~3.0m, length 0.8m): Use two 0.4m long variable diameter centering uncoupled modules 2, with built-in 25mm diameter emulsion explosive.

[0051] Weak interlayer section (1.2-2.2m, length 1.0m): Two 0.5m long water-air composite buffer isolation modules 3 are used, with only high-energy detonating cord passing through the inside, and no solid explosives are loaded.

[0052] Orifice section (0-1.2m, length 1.2m): Utilizes 3 high-energy shaped charge modules 1, each 0.4m long, with a built-in 32mm diameter emulsion explosive.

[0053] The loader connects the modules sequentially according to the 3D assembly diagram displayed on the terminal. When pushing the module into the borehole, the loader uses the delivery rod to precisely align the blue energy-absorbing side of the water-air composite buffer isolation module 3 with the direction of the surrounding rock at the arch crown.

[0054] This embodiment provides a gas storage perimeter eye variable impedance charging system based on drilling parameter inversion, comprising the following components: The drilling data acquisition module includes a high-frequency pressure sensor and a displacement sensor installed on the hydraulic circuit of the drilling rig. The high-frequency pressure sensor is used to collect data on feed pressure, rotation pressure, impact pressure, and flushing water pressure, while the displacement sensor is used to measure drill pipe displacement in real time to calculate the drilling speed. The sampling rate is no less than 50Hz to ensure sufficient data density in the hole depth direction. The acquired time-series data is converted into a hole depth spatial sequence through spatiotemporal reconstruction, and outlier signals are removed using a wavelet threshold denoising algorithm.

[0055] Edge computing terminal: Communicates with the drilling data acquisition module via wired or wireless means. After receiving the spatial sequence data matrix, the edge computing terminal calls the modified mechanical specific energy model and the UCS integrated inversion model to output a continuous hardness curve along the hole depth in real time. The terminal has a built-in decision matrix that automatically assigns the corresponding module type based on the UCS value of each charge unit, generates a module assembly BOM list, and outputs a 3D assembly instruction diagram. The calibration coefficients in the integrated inversion model are obtained through joint training of on-site rock mechanics core sampling tests and support vector regression. The spatial resolution of the continuous hardness curve is one UCS value output every 0.1m along the hole depth.

[0056] Modular variable impedance continuous charge kit: Configured according to the charge instructions, it includes multiple standardized charge modules sequentially spliced ​​together via male and female end clips. The standardized charge modules include a high-energy focusing module 1, a variable-diameter centering decoupled module 2, and a water-air composite buffer isolation module 3. The structural design, functional characteristics, and applicable conditions of each module have been detailed in the aforementioned embodiments.

[0057] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; only preferred embodiments of the present invention are illustrated. The descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. As long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0058] It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept, and these all fall within the scope of protection of this invention. Therefore, the scope of protection of this invention should be determined by the appended claims.

Claims

1. A method for loading explosives into a gas storage perimeter hole based on drilling parameter inversion, characterized in that, Includes the following steps: Step 1: On the hydraulic circuit of the rock drilling rig, real-time sampling rate of not less than 50Hz is used to collect drilling parameters during the peripheral hole drilling process. The drilling parameters include feed pressure. Rotational pressure Impact pressure Drilling speed Rotation speed and flushing water pressure The collected drilling parameters are based on time. The sequence data is spatiotemporally reconstructed, and the drilling parameters are converted into parameters based on the surrounding hole depth. The spatial distribution data is processed and denoised to obtain a smooth spatial sequence data matrix; Step 2: Based on the classical mechanical energy specific model, introduce the impact energy term to establish a modified mechanical energy specific model suitable for the impact-rotation composite drilling mode. The real-time calculation model is used, and the hydraulic system parameters of the rock drilling rig are used to replace the mechanical force at the bottom of the surrounding holes with equivalent values ​​to obtain the corrected mechanical energy distribution in the hole depth direction. Step 3: Based on the corrected mechanical specific energy distribution, a comprehensive inversion model of the uniaxial compressive strength (UCS) of the rock mass is established through nonlinear basic mapping, brittleness and cutting depth correction, and joint and fracture reduction correction, and the continuous hardness curve in the hole depth direction is output. Step 4: Based on the continuous hardness curve, divide the charge unit along the hole depth direction. According to the UCS value of each charge unit, match the corresponding charge module from the preset module types. The module types include at least a variety of functional modules suitable for different rock mass hardness ranges. Step 5: Generate a charging instruction containing the module type and arrangement order of each charging unit, assemble the modules in sequence to form a charging kit with the same depth as the hole, and push the whole kit into the borehole to complete the charging.

2. The method for variable impedance charging of gas storage perimeter holes based on drilling parameter inversion according to claim 1, characterized in that, In step one, the aperture depth of the spatiotemporal reconstruction The calculation formula is: ； In the formula, τ is the integral time variable, and the denoising process adopts the wavelet threshold denoising algorithm to remove abnormal high-frequency jump signals caused by drill pipe connection and local stuck drill.

3. The method for variable impedance charging of a gas storage perimeter hole based on drilling parameter inversion according to claim 1, characterized in that, In step two, the corrected mechanical specific energy The real-time computing model is as follows: ； In the formula, To improve the system's energy decay coefficient, The energy attenuation coefficient of the impact system. For the depth of the hole The pressure to advance, To increase the effective area of ​​the piston in the propulsion cylinder, For return oil pressure, This represents the effective area of ​​the piston on the oil return side. The cross-sectional area of ​​the drill bit. For a single impact, For the impact frequency, For drilling speed, For rotational speed, This refers to the rotational torque.

4. The method for variable impedance charging of a gas storage perimeter hole based on drilling parameter inversion according to claim 1, characterized in that, In step three, the comprehensive inversion model for the uniaxial compressive strength (UCS) of the rock mass is as follows: ； In the formula, For nonlinear fundamental mapping coefficients, This is the brittleness correction factor. This is a brittleness correction index. This is the fracture reduction factor. These are constant terms, all of which are site-specific calibration coefficients obtained through joint training of on-site rock mechanics core sampling tests and machine learning. For the depth of the hole Corrected mechanical specific energy at the location, Measured per revolution. This represents the instantaneous pressure drop of the flushing water pressure.

5. The method for variable impedance charging of a gas storage perimeter hole based on drilling parameter inversion according to claim 1, characterized in that, Step four includes: When the UCS of the charging unit is ≥80MPa, a high-energy focusing module (1) is allocated; the outer shell of the high-energy focusing module (1) is made of high-density polyethylene, and is filled with high-explosive emulsion explosive. The coupling coefficient between the outer diameter and the borehole diameter is 0.9 to 1.

0. V-shaped focusing grooves (11) with an included angle of 80° to 100° are opened on both sides of the outer shell along the axial direction. When the UCS of the charging unit is greater than or equal to 30MPa and less than 80MPa, a variable diameter centering uncoupled module (2) is allocated; the center of the variable diameter centering uncoupled module (2) is a standard diameter cartridge (21), and a thin-walled PVC pipe (22) is sleeved on the outside. The outer wall of the thin-walled PVC pipe (22) is evenly distributed with 4 to 6 variable diameter self-locking centering winglets (23), and the uncoupled coefficient is 1.5 to 2.

0. When the UCS of the charging unit is less than 30MPa, a water-air composite buffer isolation module (3) is allocated; the water-air composite buffer isolation module (3) adopts an asymmetrical eccentric structure, with a high-impedance rigid reflector plate (31) set on the side close to the excavation center, and a porous aerogel-polyurethane composite energy absorption layer (32) with a thickness of 10-15mm set on the side close to the retained surrounding rock.

6. The method for variable impedance charging of a gas storage perimeter hole based on drilling parameter inversion according to claim 5, characterized in that, The variable diameter self-locking centering wing (23) is made of shape memory alloy or elastic plastic. After being pushed into the borehole, it automatically expands and fits the borehole wall, so that the propellant roll remains in the center position inside the borehole.

7. The method for variable impedance charging of a gas storage perimeter hole based on drilling parameter inversion according to claim 5, characterized in that, The water-air composite buffer isolation module (3) has a direction indicator (33) on the end of the charge kit. In step five, when the blast hole is pushed in, the direction indicator (33) makes one side of the composite energy-absorbing layer (32) face the direction of the surrounding rock to be retained.

8. A variable impedance charging system for a gas storage perimeter hole based on drilling parameter inversion, used to implement the variable impedance charging method for a gas storage perimeter hole based on drilling parameter inversion as described in any one of claims 1 to 7, characterized in that, Also includes: The drilling data acquisition module is installed on the hydraulic circuit of the drilling rig. It is used to collect the propulsion pressure, rotation pressure, impact pressure, drilling speed, rotation speed and flushing water pressure in real time during the drilling process of the peripheral hole at a sampling rate of not less than 50Hz. The time-based sequence data is converted into a spatial sequence data matrix based on hole depth after spatiotemporal reconstruction and noise reduction. An edge computing terminal, communicatively connected to the drilling data acquisition module, receives the spatial sequence data matrix, calculates the corrected mechanical energy distribution along the hole depth direction based on a corrected mechanical energy model of the impact-rotation composite drilling mode, and outputs a continuous hardness curve along the hole depth direction through a comprehensive inversion model that includes nonlinear basic mapping, brittleness and cutting depth correction, and joint and fracture reduction correction. Then, based on the continuous hardness curve, a one-hole-one-policy charging instruction is generated; The modular variable impedance continuous charge kit is configured according to the charge instructions and includes multiple standardized charge modules that are sequentially spliced ​​together by male and female end clips. The standardized charge modules include at least two of the following: a high-energy focusing module (1) suitable for different rock hardness ranges, a variable diameter centering non-coupled module (2), and a water-air composite buffer isolation module (3).

9. The variable impedance charging system for gas storage perimeter holes based on drilling parameter inversion according to claim 8, characterized in that, The drilling data acquisition module includes a high-frequency pressure sensor and a displacement sensor installed on the hydraulic circuit of the drilling rig; the edge computing terminal has a built-in decision matrix, and the decision matrix has the following rules: when the UCS of the charging unit is ≥80MPa, the high-energy focusing module (1) is allocated; when the UCS of the charging unit is greater than or equal to 30MPa and less than 80MPa, the variable diameter centering decoupled module (2) is allocated; when the UCS of the charging unit is <30MPa, the water-air composite buffer isolation module (3) is allocated.

10. The gas storage perimeter eye variable impedance charging system based on drilling parameter inversion according to claim 8, characterized in that, The edge computing terminal is also used to generate a module assembly BOM list and output a 3D assembly instruction diagram; the calibration coefficients in the integrated inversion model are obtained by joint training of on-site rock mechanics core sampling test and support vector regression; the spatial resolution of the continuous hardness curve is to output a UCS value every 0.1m along the hole depth direction.

Images