An experimental method for gas explosion impact injury in coal mine underground

Abstract

The present application provides a kind of experimental method of coal mine underground gas explosion impact injury, belong to the field of mine safety technology.The present application simulates the limited roadway space in coal mine by adjustable modular rectangular explosion pipeline;The matrix type connected restraint cage is used to realize the accurate positioning and restraint of the biological sample in multiple points and multiple attitudes, and the real stress distribution of underground personnel is simulated.The physical parameters of the whole process of explosion are collected synchronously, and the multi-dimensional damage evaluation is completed by combining full-level medical detection, the statistical correlation analysis of explosion parameters and biological damage indexes under different working conditions is carried out, and the standardized experimental evaluation system of gas explosion impact injury is established.The present application solves the problem of discrete damage data and single evaluation dimension in traditional experiment, and provides a scientific platform for precise medical rescue and protective equipment research and development after coal mine disaster, and the experiment has strong controllability and repeatability.

Description

Technical Field

[0001] This invention relates to the field of mine safety technology, specifically to an experimental method for gas explosion impact injuries in underground coal mines. Background Technology

[0002] Coal accounts for a significant proportion of primary energy consumption in the energy structure and is the foundation for ensuring a secure and stable energy supply. As coal mining extends to deeper underground locations, the high-gas, high-stress working environment becomes increasingly complex, and the safety risks of gas explosions persist. The impact injuries, burns, and toxic gas poisoning caused by gas explosions are characterized by their instantaneous occurrence and complex injury types, posing significant challenges to post-disaster medical emergency rescue in coal mines.

[0003] Existing research largely focuses on the physical and dynamic evolution of gas explosions, with limited studies addressing the intersection of gas explosion injuries and medical treatment. Research on the damage patterns of living organisms in complex tunnel environments remains significantly insufficient. Currently, there is a lack of standardized experimental methods capable of simulating real-world underground spatial distribution, biological stress postures, and multi-dimensional medical assessments. Existing animal experimental methods cannot effectively simulate the environmental characteristics of confined underground spaces, and the posture of experimental samples under shock waves exhibits randomness, resulting in highly dispersed damage data that makes it difficult to form stable and repeatable experimental conclusions. This hinders the provision of reliable experimental support for optimizing post-disaster emergency rescue plans.

[0004] Therefore, an experimental method for detecting gas explosion shock injuries in underground coal mines is proposed. Summary of the Invention

[0005] The present invention aims to solve the problems mentioned in the background art by providing an experimental method for treating gas explosion shock injuries in coal mines.

[0006] The specific technical solution is as follows: An experimental method for simulating and quantitatively evaluating the impact damage of gas explosions in confined spaces of coal mines on organisms includes the following steps: S1: Construct a roadway explosion test system. The system includes a modular rectangular test pipeline consisting of a detonation section and a propagation section that are sequentially sealed and connected. It is equipped with a gas distribution unit, an ignition unit, a synchronization control unit, and a multi-physics field data acquisition unit. By adjusting the combined length of the pipeline between the detonation section and the propagation section, the system simulates the confined roadway space of coal mines at different scales. The detonation section and the propagation section are isolated by a breakable sealing partition. S2: Standardized preprocessing and posture constraint of biological samples. Experimental rats are grouped and placed in matrix-type conjoined constraint cages. The constraint cages are equipped with multiple independent and closed cage positions to form spatial constraints on individual rats to fix their impact posture. The constraint cages carrying rats are fixed at preset measuring point positions in the propagation section pipe. The impact posture of the rats is switched by adjusting the installation orientation of the constraint cages. S3: Standardized simulation and synchronous triggering of gas explosion environment. After the airtightness of the detonation section is checked, a vacuum is drawn. A methane-air mixture of a preset concentration is introduced into the detonation section by the partial pressure method. The circulation unit is turned on to uniformly premix the mixture and let it stand. The ignition unit is triggered by the synchronous control unit to detonate the mixture. At the same time, the multi-physics field data acquisition unit is triggered to synchronously collect the physical and mechanical parameters of the entire explosion process in the pipeline. S4: Comprehensive assessment of blast impact injury. After the explosion, the harmful gas in the pipeline was evacuated. After the rat was removed, an immediate initial assessment of the injury was completed. Then, imaging tests, blood biochemistry tests, histopathological tests and molecular biological tests were carried out in sequence to obtain multi-organ and multi-dimensional quantitative indicators of injury in rats. S5: Multi-condition control experiment, replace the sealing baffle between the detonation section and the propagation section, clean the explosion residue in the pipeline, repeat steps S2 to S4, and carry out multiple sets of parallel control experiments under different methane concentrations, different measuring point distances, and different impact postures. S6: Construction of Damage Pattern Analysis and Evaluation System. Statistical correlation analysis is conducted on the explosion physics and mechanics parameters and biological damage quantitative indicators collected from each group of experiments. A quantitative correlation model between explosion exposure conditions and the degree of damage to organisms is established, including the aforementioned single-factor core injury model, multi-factor coupling correction model, organ-specific injury model, and damage grading judgment model. A precise mapping relationship between explosion exposure conditions and the degree of damage to organisms is established, forming a standardized experimental evaluation system for gas explosion impact injuries in coal mines.

[0007] As a preferred embodiment of the present invention, the rectangular experimental pipe is made of rectangular steel pipe with an inner cross-sectional dimension of 500mm×500mm and a wall thickness of 2cm; the detonation section and the propagation section are both spliced ​​together from multiple sections of pipe with a single section length of 1m, 2m, 3m or 4m, and the splice is fixedly connected by a sealing flange; the breakable sealing partition is made of PTFE film and is clamped and fixed between the flanges connecting the detonation section and the propagation section.

[0008] As a preferred embodiment of the present invention, the matrix-type integrated constraint cage is a 3×3 matrix-type integrated steel cage containing 9 independent and enclosed cage positions. The cage positions are divided into three layers, with 3 cage positions evenly arranged in each layer. The internal dimensions of a single cage position are 165mm in length, 65mm in width, and 80mm in height. The cage is made of a grid structure with a main rib diameter of 4mm, a secondary rib diameter of 2mm, and a grid aperture of 25mm.

[0009] As a preferred embodiment of the present invention, in step S2, the impact posture of the rats is switched by adjusting the installation orientation of the restraint cage. The impact posture includes a standing posture simulating the standing state of underground personnel and a lying posture simulating the prone state of underground personnel. In the same group of experiments, the impact posture of all rats in the restraint cage is kept consistent.

[0010] As a preferred embodiment of the present invention, in step S2, the preset measuring point positions in the propagation section pipe include position 1, which is 3m away from the ignition end of the detonation section; position 2, which is 6m away from the ignition end of the detonation section; and position 3, which is 12m away from the ignition end of the detonation section. In the same group of experiments, the entire constraint cage is fixed at a single preset measuring point position, and different groups of experiments correspond to different preset measuring point positions.

[0011] As a preferred embodiment of the present invention, in step S3, the methane-air mixture of the preset concentration includes a lower limit concentration mixture with a methane volume fraction of 7.5%, a stoichiometric concentration mixture with a methane volume fraction of 9.5%, and an upper limit concentration mixture with a methane volume fraction of 11.5%; a single concentration of methane-air mixture is used in the same group of experiments, and different concentrations of methane-air mixture are used in different groups of experiments.

[0012] As a preferred embodiment of the present invention, in step S3, when the circulation unit performs uniform premixing of the mixed gas, the volume of the circulating gas is not less than 3 times the volume of the inner cavity of the detonation section; after the premixing is completed, the circulation unit is turned off, and the mixed gas is left to stand for not less than 15 minutes before triggering ignition and detonation.

[0013] As a preferred embodiment of the present invention, in step S3, the multi-physics data acquisition unit includes multiple pressure sensors, temperature sensors and CO sensors arranged along the pipeline axis, as well as a high-speed data acquisition instrument; when the synchronous control unit triggers ignition, it triggers the high-speed data acquisition instrument to synchronously acquire real-time change data of shock wave overpressure, ambient temperature and CO concentration at each measuring point in the pipeline at a sampling frequency of not less than 1MHz.

[0014] As a preferred embodiment of the present invention, in step S4, the immediate initial injury assessment includes observing and recording the survival status, external body surface damage, and behavioral and consciousness status of the experimental rats, while simultaneously monitoring the rats' heart rate, respiration, and blood pressure vital signs in real time to complete the preliminary injury severity grading assessment of the blast impact injury.

[0015] As a preferred embodiment of the present invention, in step S4, the imaging detection includes one or more of X-ray examination, ultrasound examination, CT examination, and MRI examination to perform in vivo scanning detection of the rat's cranium, thoracic cavity, abdominal cavity organs and skeletal structure, and to obtain morphological damage imaging data of the rat's organs and bones.

[0016] In a preferred embodiment of the present invention, in step S4, the blood biochemical detection includes quantitative detection of liver function indicators, kidney function indicators, myocardial injury indicators, oxidative stress indicators, and nerve injury-related indicators in rat blood samples; the liver function indicators include alanine aminotransferase and aspartate aminotransferase, the kidney function indicators include blood urea nitrogen and creatinine, and the myocardial injury indicators include lactate dehydrogenase.

[0017] As a preferred embodiment of the present invention, in step S4, the histopathological examination includes gross morphological observation of the major organs of rats, such as the brain, heart, liver, lungs, and kidneys, and recording changes in organ morphology such as hemorrhage, edema, and rupture; after fixing, dehydrating, embedding, sectioning, and staining the target organ tissue with hematoxylin and eosin (HE), the pathological changes of tissue structure, cell necrosis, inflammatory cell infiltration, hemorrhage, and edema are observed under a microscope to complete the quantitative analysis of the degree of damage at the tissue level.

[0018] As a preferred embodiment of the present invention, in step S4, the molecular biological detection includes extracting RNA and protein from rat target organ tissues, using real-time quantitative PCR technology to detect the mRNA expression level of explosion damage-related genes, using Western blot technology to detect the expression level of explosion damage-related proteins, and analyzing the molecular mechanisms of inflammatory response, oxidative stress response, and cell damage response related to explosion impact injury.

[0019] As a preferred embodiment of the present invention, in step S6, the statistical correlation analysis includes analyzing the inter-group differences between the explosion physics and mechanical parameters under different methane concentrations, different measuring point distances, and different impact postures, and the corresponding group rat multi-dimensional damage quantitative indicators. This establishes a full-chain quantitative correlation model system between shock wave overpressure, exposure distance, impact posture, and the degree of damage to multiple organs of the organism. Unlike the simple correlation analysis that can only be carried out in the prior art, this model system can directly and accurately calculate the comprehensive damage degree of the organism and the specific damage degree of each target organ through measured explosion physics parameters, and complete the standardized grading of the damage degree. This achieves a technical breakthrough from qualitative correlation analysis to quantitative and accurate prediction of gas explosion impact injuries, and forms a grading evaluation standard for gas explosion impact injuries in coal mines.

[0020] The present invention has the following beneficial effects: This method fills the gap in experimental methods at the intersection of mine safety and biomedicine. For the first time, it establishes a standardized experimental method covering the entire process of underground scenario simulation, biological sample attitude control, synchronous acquisition of explosion parameters, multi-dimensional damage assessment, and damage pattern analysis, thus solving the problem of disconnect between engineering explosion simulation and medical damage assessment in existing research.

[0021] Through modular pipeline design, the combined length of the pipeline can be flexibly adjusted to adapt to the simulation needs of underground roadways of different scales. It can realistically reproduce the propagation law of gas explosion in confined underground spaces. The experimental scenario is highly consistent with the actual accident scenario in underground mines, and the experimental results obtained are more practically valuable.

[0022] The specialized conjoined restraint cage design allows for stable spatial restraint of multiple experimental animals simultaneously, ensuring that all animals in the same experimental group are in a completely identical explosion exposure environment. At the same time, the impact posture of the animals can be flexibly adjusted to simulate the real stress state of personnel underground, effectively eliminating experimental interference caused by random changes in animal posture, significantly reducing the dispersion of experimental data, and improving the stability and repeatability of experimental results.

[0023] The synchronous control of ignition and data acquisition design ensures the temporal correspondence between explosion physical parameters and biological damage processes, providing accurate basic data for the correlation analysis of explosion conditions and damage levels, and avoiding analytical errors caused by data timing misalignment.

[0024] Through a comprehensive medical injury assessment design, we can obtain complete information on the damage caused by the explosion to animals, from gross appearance, in vivo imaging, organ function, histopathology to molecular mechanisms. This fully restores the complete injury characteristics of gas explosion shock injuries, avoiding information omissions caused by single-dimensional assessments, and making the assessment results more comprehensive and accurate.

[0025] Through the experimental design of multi - working - condition parallel comparison, the variation law of damage under different gas concentrations, different exposure distances, and different impacted postures can be systematically sorted out, establishing a stable correlation between the explosion exposure conditions and the degree of biological damage. The finally formed standardized experimental evaluation system can provide a reliable experimental platform and data support for the optimization of post - disaster emergency rescue plans in coal mines and the research and development of personal protective equipment.

[0026] The operation process of this method is standardized, and the experimental conditions are highly controllable. The experimental results of different experimental batches and different experimental sites have the basis for horizontal comparison, and it has great application value for promotion. At the same time, the modular design of the experimental device has good expandability. In addition to the research on gas explosion shock injuries, it can also be expanded for experimental research related to explosion - harmful gases, with a wide range of applications.

[0027] The present invention first constructs a full - chain quantitative correlation model system covering core injury relationships, multi - factor coupling correction, organ - specific injuries, and injury grading determination, breaking through the technical limitation of the prior art that can only carry out simple correlation analysis between explosion parameters and injury indicators. This model system has clear mathematical expressions, fixed fitting parameters and correction coefficients, and standardized injury grading rules. Those skilled in the art can directly measure the explosion physical parameters underground to accurately predict the comprehensive injury degree of personnel at the accident site and the injury situation of core target organs, quickly complete injury grading, providing a directly applicable mathematical model and quantitative standard for rapid hierarchical treatment of personnel, optimization of emergency rescue plans, and quantitative evaluation of the protective effect of personal protective equipment after gas explosion accidents in coal mines, filling the gap in quantitative research in the cross - field of mine safety and emergency medicine, and having great industry application value and promotion prospects. Brief Description of the Drawings

[0028] Figure 1 It is a schematic structural diagram of the gas explosion experimental device used in the experimental method for gas explosion shock injuries in coal mines of the present invention. This figure shows the overall layout of the experimental device and the connection relationship of each functional module, including a detonation section and a propagation section that are hermetically spliced in sequence, as well as a gas distribution unit, an ignition unit, a synchronous control unit, a multi - physical - field data acquisition unit, and a tail gas treatment unit arranged in a supporting manner. The figure marks the sealed partition between the detonation section and the propagation section, the installation position of the ignition rod, the sensor points arranged along the axial direction of the pipeline, and the setting positions of various control valves, fully demonstrating the core structure of the experimental device and the cooperation logic of each module, and is used to intuitively illustrate the hardware carrier composition of this experimental method.

[0029] Figure 2This is a schematic diagram of the matrix-type connected restraint cage structure used in the experimental method of this invention. The diagram shows the 3×3 matrix-type connected steel cage structure used to immobilize experimental rats, presenting the overall layout of three layers of cages, each layer with three independent enclosed cage positions. The specifications of the main and secondary ribs of the cage mesh and the dimensional parameters of individual cage positions are labeled. This diagram clearly shows the mesh cutout structure and independent restraint design of the cage, illustrating the specialized device structure used in this experimental method for posture fixation and spatial positioning of experimental rats.

[0030] Figure 3 This diagram illustrates the surface damage of rats after an explosion in an embodiment of the present invention. It shows a comparison of the surface appearance of rats in the normal control group and rats in experimental groups under different explosion conditions, clearly demonstrating the differences in the extent and severity of fur burns and surface injuries under different explosion exposure conditions. This visually reflects the acute injury characteristics caused by the gas explosion impact on the surface of the experimental rats.

[0031] Figure 4 This is a schematic diagram illustrating the gross morphological changes of rat internal organs after an explosion in an embodiment of the present invention. The diagram shows a comparison of the gross anatomical morphology of the core internal organs of rats in the normal control group and the explosion experimental group, covering the main target organs of the explosion impact, such as the brain, heart, liver, lungs, and kidneys. It clearly presents the gross morphological abnormalities of the rat organs after the explosion impact, such as congestion, edema, ecchymosis, and focal rupture, and is used to visually reflect the gross damage caused by the gas explosion impact to the important organs in the rats.

[0032] Figure 5 This is a schematic diagram of the imaging examination results of rats in an embodiment of the present invention. The figure shows the multiplanar CT scan results of the rats after the explosion, including cross-sectional, sagittal, and coronal images, which clearly reflect the imaging changes of the thoracic and abdominal organs after the explosion impact. The main abnormal signs are diffuse pulmonary effusion and pleural and peritoneal effusions, thus visually revealing the damage caused by the gas explosion to the rats' internal organs in a living state.

[0033] Figure 6 This is a schematic diagram of the X-ray examination results of rats in an embodiment of the present invention. This figure shows a comparison of X-ray films of the limbs and chest of rats in the normal control group and the explosion experimental group. It clearly presents the bony damage manifestations such as rib fractures and discontinuity of long bones in the limbs after the explosion impact. It is used to intuitively reflect the damage characteristics caused by the gas explosion impact to the rat skeletal system and provide imaging evidence for the judgment of bony damage.

[0034] Figure 7This is a schematic diagram showing the changes in serum biochemical indicators of rats in each group in this embodiment of the invention. This figure is a bar chart comparing serum biochemical indicators of rats in the normal control group and experimental groups at different exposure locations. It covers core detection indicators related to liver function, kidney function, and myocardial injury, clearly showing the differences in the expression levels of various biochemical indicators of rats under different explosion conditions, and is used to quantify the degree of damage caused by gas explosion impact to the function of important organs of rats. Figure 8 This is a view of a rat restrained in a matrix-type conjoined cage. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this application. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0037] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0038] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] Reference Figure 1-8 The following examples are provided.

[0040] The experimental method for assessing the impact injury of underground gas explosions in coal mines provided in this embodiment is characterized by simulating and quantifying the impact damage to organisms caused by gas explosions in confined spaces underground in coal mines. It includes the following steps: S1: Construct a roadway explosion test system. The system includes a modular rectangular test pipeline consisting of a detonation section and a propagation section that are sealed and connected in sequence. It is equipped with a gas distribution unit, an ignition unit, a synchronization control unit, and a multi-physics field data acquisition unit. By adjusting the combined length of the pipeline between the detonation section and the propagation section, the system simulates the confined roadway space of coal mines at different scales. The detonation section and the propagation section are isolated by a breakable sealing partition. S2: Standardized preprocessing and posture constraint of biological samples. Experimental rats were grouped and placed in matrix-type conjoined constraint cages. The constraint cages were set with multiple independent and closed cage positions to form spatial constraints on individual rats to fix their impact posture. The constraint cages carrying the rats were fixed at preset measuring point positions in the propagation section pipe. The impact posture of the rats was switched by adjusting the installation orientation of the constraint cages. S3: Standardized simulation and synchronous triggering of gas explosion environment. After the airtightness of the detonation section is checked, a vacuum is drawn. A methane-air mixture of a preset concentration is introduced into the detonation section by the partial pressure method. The circulation unit is turned on to uniformly premix the mixture and let it stand. The ignition unit is triggered by the synchronous control unit to detonate the mixture. At the same time, the multi-physics field data acquisition unit is triggered to synchronously collect the physical and mechanical parameters of the entire explosion process in the pipeline. S4: Comprehensive assessment of blast impact injury. After the explosion, the harmful gas in the pipeline was evacuated. After the rat was removed, an immediate initial assessment of the injury was completed. Then, imaging tests, blood biochemistry tests, histopathological tests and molecular biological tests were carried out in sequence to obtain multi-organ and multi-dimensional quantitative indicators of injury in rats. S5: Multi-condition control experiment, replace the sealing baffle between the detonation section and the propagation section, clean the explosion residue in the pipeline, repeat steps S2 to S4, and carry out multiple sets of parallel control experiments under different methane concentrations, different measuring point distances, and different impact postures. S6: Construction of Damage Pattern Analysis and Evaluation System. Statistical correlation analysis is conducted on the explosion physics and mechanics parameters and biological damage quantitative indicators collected from each group of experiments. A quantitative correlation model between explosion exposure conditions and the degree of damage to organisms is established, including the aforementioned single-factor core injury model, multi-factor coupling correction model, organ-specific injury model, and damage grading judgment model. A precise mapping relationship between explosion exposure conditions and the degree of damage to organisms is established, forming a standardized experimental evaluation system for gas explosion impact injuries in coal mines.

[0041] By adopting the above scheme, a modular experimental system is built, which can flexibly adapt to different underground tunnel simulation needs, making the experimental environment closer to the real underground operation scenario and reducing the deviation caused by environmental simulation. Standardized biological sample processing and posture constraint procedures can stably control irrelevant variables during the experiment, avoiding interference from non-experimental factors. Synchronized control of explosion triggering and data acquisition ensures the correspondence between explosion process parameters and biological damage data, making the correlation analysis between the two types of data more accurate. The full-process damage assessment design can comprehensively cover the impact of the explosion on different levels of the organism, comprehensively acquiring various damage-related information. The design of multiple control experiments can systematically analyze the differences in damage under different experimental conditions, making the experimental patterns more complete. The final standardized experimental evaluation system can provide a unified execution and judgment standard for subsequent similar experiments, providing a basis for horizontal comparison of results from different experiments.

[0042] Specifically, in this embodiment, the rectangular experimental pipeline is made of rectangular steel pipe with an inner cross-sectional dimension of 500mm×500mm and a pipe wall thickness of 2cm. Both the detonation section and the propagation section are spliced ​​together from multiple sections of pipe with a single section length of 1m, 2m, 3m or 4m, and the splice is fixedly connected by a sealing flange. The breakable sealing partition is made of PTFE film and is clamped and fixed between the flanges connecting the detonation section and the propagation section.

[0043] This design utilizes steel to construct the experimental piping, capable of withstanding the high-temperature and high-pressure environment generated during an explosion, ensuring the stability and safety of the experiment. The multi-section piping structure allows for flexible adjustment of the overall length to suit different simulation scenarios. Flange connections ensure a tight seal at the pipe joints, preventing gas leakage from affecting the accuracy of gas distribution and thus guaranteeing the stability of the explosion conditions. A breakable sealing baffle between the two sections isolates them during gas distribution and detonation, ensuring precise gas concentration. This baffle breaks easily during the explosion without interfering with the normal propagation of the shock wave, making the explosion environment within the propagation section more closely resemble the actual shock wave propagation patterns in a mine.

[0044] Specifically, in this embodiment, the matrix-type integrated constraint cage is a 3×3 matrix-type integrated steel cage containing 9 independent and enclosed cage positions. The cage positions are divided into three layers, with 3 cage positions evenly arranged in each layer. The internal dimensions of a single cage position are 165mm in length, 65mm in width, and 80mm in height. The cage is made of a mesh structure with a main mesh reinforcement diameter of 4mm, a secondary mesh reinforcement diameter of 2mm, and a mesh aperture of 25mm.

[0045] The integrated cage structure in this design can simultaneously restrain multiple experimental animals, ensuring that all animals in the same experimental group are in a completely consistent explosion exposure environment, reducing bias in experimental data within the group. The independent cage design avoids interference between experimental animals, ensuring that each animal maintains a stable impact state during the explosion and does not shift position. The mesh cage design does not significantly obstruct the propagation of the shock wave, ensuring that the impact environment received by the experimental animals is consistent with that in a real tunnel, while the cage itself has sufficient structural strength to prevent deformation or damage during the explosion, continuously maintaining the restraint effect on the animals.

[0046] Specifically, in this embodiment, in step S2, the impact posture of the rats is switched by adjusting the installation position of the restraint cage. The impact posture includes the standing posture simulating the standing state of underground personnel and the lying posture simulating the prone state of underground personnel. In the same group of experiments, the impact posture of all rats in the restraint cage is kept consistent.

[0047] This method allows for the simulation of different stress states of personnel underground by adjusting the cage's installation orientation to change the animal's impact posture, making the experimental results more closely resemble the injuries suffered by personnel in real accidents. Maintaining a consistent impact posture for animals within the same experimental group eliminates interference from experimental variables caused by posture differences, improves the stability and consistency of experimental data within the same group, and facilitates accurate analysis of the actual impact of different experimental conditions on injury results.

[0048] Specifically, in this embodiment, in step S2, the preset measuring point positions in the propagation section pipe include position 1, which is 3m away from the ignition end of the detonation section; position 2, which is 6m away from the ignition end of the detonation section; and position 3, which is 12m away from the ignition end of the detonation section. In the same group of experiments, the entire constraint cage is fixed at a single preset measuring point position, and different groups of experiments correspond to different preset measuring point positions.

[0049] This scheme sets up measuring points at different distances within the propagation section to simulate the exposure environment at different locations during the propagation of the blast shock wave in the tunnel, allowing the system to obtain biological damage under different shock wave intensities. Fixing the cages at a single measuring point in the same group of experiments ensures that all animals in the group experience identical blast exposure conditions, eliminating interference from distance differences, improving the comparability of experimental data, and accurately identifying the correlation between exposure distance and damage severity.

[0050] Specifically, in this embodiment, in step S3, the methane-air mixture of preset concentration includes a lower limit concentration mixture with a methane volume fraction of 7.5%, a stoichiometric concentration mixture with a methane volume fraction of 9.5%, and an upper limit concentration mixture with a methane volume fraction of 11.5%. The same group of experiments uses a single concentration of methane-air mixture, and different groups of experiments correspond to different concentrations of methane-air mixture.

[0051] This scheme employs mixed gas concentrations covering different explosion ranges, comprehensively simulating various typical scenarios of underground gas accumulation. This makes the experimental conditions more closely resemble real-world accident occurrences, avoiding limitations imposed by a single explosion condition. Different experimental groups use mixed gas concentrations, allowing for a systematic comparison of explosion damage differences under different gas concentrations. This fully covers different characteristic ranges of gas explosions, broadening the applicability of the experimental conclusions.

[0052] Specifically, in this embodiment, in step S3, when the circulation unit premixes the mixed gas uniformly, the volume of the circulating gas is not less than 3 times the volume of the inner cavity of the detonation section; after the premixing is completed, the circulation unit is turned off, and the mixed gas is left to stand for no less than 15 minutes before triggering ignition and detonation.

[0053] This method involves sufficient premixing of the gas mixture to ensure thorough and uniform mixing of methane and air within the detonation stage, preventing localized concentration deviations from affecting the stability of the explosion. After premixing, allowing the mixture to settle completely eliminates turbulence, ensuring a stable and uniform gas state at ignition, improving the consistency of each explosion and enhancing experimental repeatability.

[0054] Specifically, in this embodiment, in step S3, the multi-physics data acquisition unit includes multiple pressure sensors, temperature sensors, and CO sensors arranged along the pipeline axis, as well as a high-speed data acquisition instrument; while the synchronous control unit triggers ignition, it triggers the high-speed data acquisition instrument to synchronously acquire real-time change data of shock wave overpressure, ambient temperature, and CO concentration at each measuring point in the pipeline at a sampling frequency of not less than 1MHz.

[0055] This solution deploys multiple types of sensors along the pipeline axis to comprehensively collect various physical parameters during the explosion process, fully reconstructing the entire explosion's characteristics. The synchronously triggered high-speed acquisition mode ensures that the collected physical parameters perfectly correspond to the time points of the explosion process and biological damage, providing accurate foundational data for subsequent parameter-damage correlation analysis. The high-frequency sampling settings can completely capture the instantaneous changes of the explosion shock wave, ensuring no characteristic information is missed during the explosion process, resulting in more accurate physical data.

[0056] Specifically, in this embodiment, step S4, the immediate initial injury assessment, includes observing and recording the survival status, external body surface damage, and behavioral and consciousness status of the experimental rats, while simultaneously monitoring the rats' heart rate, respiration, blood pressure, and other vital signs in real time to complete the preliminary injury severity grading assessment of the blast impact injury.

[0057] The initial damage assessment conducted immediately after the explosion in this scheme can obtain the immediate impact of the explosion on the animal, capturing changes in vital signs and acute injury manifestations within a short period after the explosion, without missing relevant information about acute injury over time. The multi-faceted assessment design can quickly classify the degree of injury, providing a basis for subsequent in-depth detection grouping and detection direction, and can also preliminarily establish a direct correlation between the explosion condition and the degree of injury.

[0058] Specifically, in this embodiment, step S4, imaging detection includes using one or more of X-ray examination, ultrasound examination, CT examination, and MRI examination to perform in vivo scanning detection of the rat's cranium, thoracic cavity, abdominal cavity organs and skeletal structure, and to obtain morphological damage imaging data of the rat's organs and bones.

[0059] This approach employs multiple imaging techniques, enabling complete observation of morphological changes in the internal organs and skeleton of animals in vivo. Damage information of internal structures can be obtained without euthanizing the animal, allowing for dynamic tracking of damage progression. Comprehensive detection of multiple sites covers the main internal tissues and structures affected by blast injuries, ensuring no internal structural damage is overlooked, and providing intuitive imaging evidence for assessing the degree of injury.

[0060] Specifically, in this embodiment, step S4, blood biochemical detection, includes quantitative detection of liver function indicators, kidney function indicators, myocardial injury indicators, oxidative stress indicators, and nerve injury-related indicators in rat blood samples; liver function indicators include alanine aminotransferase and aspartate aminotransferase, kidney function indicators include blood urea nitrogen and creatinine, and myocardial injury indicators include lactate dehydrogenase.

[0061] This approach quantitatively detects biochemical indicators corresponding to the functions of multiple organs, reflecting the damage caused by the explosion to different organs in animals at a functional level, thus compensating for the inability of morphological testing to determine functional damage. The comprehensive coverage of multiple indicators allows for a systematic assessment of the impact of the explosion on the function of multiple vital organs, while also reflecting the degree of stress and damage response in the body, providing objective laboratory data support for the quantitative grading of damage severity.

[0062] Specifically, in this embodiment, step S4 involves histopathological examination, including gross morphological observation of the major organs of rats (brain, heart, liver, lungs, and kidneys), recording changes in organ morphology such as hemorrhage, edema, and rupture; after fixing, dehydrating, embedding, sectioning, and staining the target organ tissue with hematoxylin and eosin (HE), the pathological changes in tissue structure, cell necrosis, inflammatory cell infiltration, hemorrhage, and edema are observed under a microscope to complete the quantitative analysis of the degree of damage at the tissue level.

[0063] This approach, through layer-by-layer observation from the gross morphology to the microstructure of organs, comprehensively presents the damage and changes in organs and tissues caused by explosions, from macroscopic to microscopic levels, and precisely locates the specific location and severity of the damage. Microscopic observation of stained tissue sections clearly reveals pathological changes at the cellular level, clarifying the pathological type and progression stage of the injury, providing direct histological evidence for the analysis of the damage mechanism of blast injuries, and enabling precise quantitative comparison of the degree of damage under different working conditions.

[0064] Specifically, in this embodiment, step S4, molecular biological detection, includes extracting RNA and proteins from rat target organ tissues, using real-time quantitative PCR to detect the mRNA expression level of explosion damage-related genes, using Western blot to detect the expression level of explosion damage-related proteins, and analyzing the molecular mechanisms of inflammatory response, oxidative stress response, and cell damage response related to explosion impact injury.

[0065] This protocol detects the expression levels of injury-related genes and proteins, revealing the intrinsic mechanisms of blast injuries at the molecular level and clarifying the specific molecular pathways through which explosions cause tissue and organ damage. Analyzing molecular indicators of various injury-related responses in the body can supplement the limitations of macroscopic and tissue-level detection, explaining the occurrence and development of injury from a fundamental biological perspective, and providing basic experimental evidence for subsequent target screening for injury prevention and treatment.

[0066] Specifically, in this embodiment, step S6 involves statistical correlation analysis, which includes analyzing the inter-group differences between the explosion physics and mechanics parameters under different methane concentrations, different measuring point distances, and different impact postures, and the corresponding group of rat multidimensional damage quantitative indicators. A quantitative correlation model is established between shock wave overpressure, exposure distance, impact posture, and the degree of damage to multiple organs of the organism, forming a grading evaluation standard for gas explosion shock injuries in coal mines.

[0067] This scheme employs correlation analysis between explosion physical parameters and biological damage indicators to clarify the intrinsic relationship between different explosion exposure conditions and the degree of damage to organisms, and to outline the damage variation patterns under different working conditions. Significance analysis of inter-group differences eliminates the interference of random factors on experimental results, making the derived damage patterns more scientific and reliable. The final grading evaluation criteria provide a unified evaluation basis for similar gas explosion impact injury experiments, ensuring the comparability of results from different experiments, and also serving as a reference for personnel injury prediction and emergency treatment planning after underground accidents.

[0068] Working principle: This method integrates mine safety engineering and biomedical engineering to fully recreate the real scenario of underground gas explosions in coal mines. At the same time, it establishes the correlation between explosion conditions and biological injuries, enabling standardized experimental research on gas explosion impact injuries.

[0069] First, a modular, interconnected pipe structure was used to construct an explosion propagation space that matches the characteristics of confined roadways in coal mines. This allowed for the reconstruction of the actual patterns of shock wave propagation, temperature field changes, and harmful gas diffusion during a gas explosion, ensuring consistency between the experimental environment and real-world underground accident scenarios. A dedicated, integrated constraint cage structure provided stable spatial constraint for the experimental biological samples. Simultaneously, the impact posture of the samples could be adjusted to simulate the stress state of underground workers during an explosion, eliminating experimental variable interference caused by random changes in sample posture and ensuring that all samples in the same experimental group experienced completely identical explosion exposure conditions.

[0070] By employing synchronous control, multiphysics data acquisition is initiated simultaneously with the triggering of the explosion ignition, comprehensively recording all physical parameters throughout the entire explosion process. This ensures that the acquired physical data fully corresponds to the explosion impact process experienced by the biological sample, providing accurate foundational data for subsequent damage correlation analysis. After the explosion, comprehensive medical testing, ranging from gross appearance to the molecular level, is used to fully acquire information on the damage to multiple organs and layers of the biological sample caused by the explosion, comprehensively reconstructing the damage characteristics of gas explosion impact injuries.

[0071] Through multiple sets of parallel control experiments, the experimental conditions such as gas concentration, exposure distance, and impact posture of the samples were systematically adjusted. The differences between the explosion physical parameters and biological damage data under different working conditions were compared. Finally, a quantitative correlation between explosion exposure conditions and the degree of biological damage was established, forming a standardized experimental evaluation system for gas explosion impact injuries.

[0072] How to use: The first step is to complete the construction and debugging of the experimental setup. Based on the simulated scenario required for the experiment, pipes of corresponding lengths are spliced ​​together to form the detonation section and the propagation section. The two sections are isolated by a sealing partition. At the same time, the gas distribution unit, ignition unit, synchronization control unit, data acquisition unit, and exhaust gas treatment unit are installed and deployed. The airtightness of the device is verified and the linkage debugging of each unit is completed to ensure that each module can work normally and collaboratively.

[0073] The second step is to complete the pretreatment and grouping of experimental samples. Select experimental animals that meet the experimental requirements, acclimate them to the environment before the experiment, record basic physiological indicators, and randomly group them according to the experimental design, setting up corresponding control and experimental groups.

[0074] The third step is to fix and install the experimental samples. The grouped experimental animals are placed into their individual cages in the conjoined restraint cages. The cages are then closed to restrict the animals' range of motion. The installation orientation of the restraint cages is adjusted according to the experimental design to fix the animals' impact posture. Finally, the loaded restraint cages are fixed in the preset positions within the propagation section.

[0075] The fourth step is to complete the explosion environment simulation and synchronous triggering. The detonation section is evacuated, and a mixture of methane and air is introduced according to the concentration requirements of the experimental design. The circulation unit is activated to fully premix the mixture. After premixing, the mixture is allowed to stand to stabilize. The ignition unit is triggered by the synchronous controller to detonate the mixture, and at the same time, the data acquisition unit is triggered to synchronously collect various physical parameters of the entire explosion process.

[0076] The fifth step is to complete a comprehensive assessment of the blast impact injuries. After the explosion, the harmful gases in the pipeline are completely vented through the exhaust gas treatment unit. The experimental animals are then quickly removed, and their survival status, external injuries, and vital signs are observed and preliminarily assessed immediately. Imaging tests, blood biochemistry tests, histopathological tests, and molecular biological tests are then conducted in sequence to obtain comprehensive quantitative data on the damage to multiple organs and at multiple levels.

[0077] Step 6: Complete the parallel control experiment under multiple operating conditions. After completing a single group experiment, replace the sealing partition with a brand new one, thoroughly clean the inside of the pipeline to remove any explosion residue, replace the experimental animals with new ones, and repeat steps 3 to 5 to complete all groups of experiments under different experimental conditions in sequence.

[0078] The seventh step is to integrate and analyze the experimental data. Collect the explosion physics parameters and biological damage data from all groups of experiments, perform inter-group difference analysis and correlation analysis using statistical methods, identify the patterns of biological damage changes under different experimental conditions, and ultimately form a standardized experimental evaluation system for gas explosion impact injuries.

[0079] In addition, the following implementation examples are also provided in this specific embodiment.

[0080] This embodiment is used to illustrate the complete technical solution of the present invention in detail. Those skilled in the art can repeat the experiment based on this embodiment to obtain stable and repeatable experimental results.

[0081] I. Experimental Setup and System Debugging The tunnel explosion test system used in this implementation example corresponds to the attached... Figure 1 The structure and specific construction scheme are as follows: 1. The modular experimental piping is made of Q235 rectangular steel pipe with an internal cross-sectional dimension of 500mm×500mm and a wall thickness of 2cm. Individual pipe sections are available in four lengths: 1m, 2m, 3m, and 4m. Each section is bolted together using a flange with a high-pressure resistant sealing gasket, allowing for flexible adjustment of the splicing length according to experimental requirements.

[0082] 2. The pipeline is divided into an ignition section and a propagation section. The ignition section consists of two 2m sections of pipe spliced ​​together, with a total length of 4m. The propagation section consists of three 4m sections of pipe spliced ​​together, with a total length of 12m. A PTFE membrane is clamped and fixed between the connecting flanges of the ignition section and the propagation section as a breakable sealing partition to completely seal and isolate the two sections of pipeline.

[0083] 3. The complete set of supporting functional units includes a gas distribution unit with a methane cylinder, vacuum pump, air compressor, explosion-proof circulating pump, vacuum pressure gauge, methane concentration gauge, and injection valve, exhaust valve, and circulation control valve; an ignition unit with an adjustable high-energy igniter and ignition rod, the ignition rod being fixed at the center of the closed end of the detonation section; a synchronization control unit using a programmable synchronous controller, electrically connected to the igniter, high-speed data acquisition instrument, and high-speed camera to achieve synchronous triggering of ignition, data acquisition, and video recording; visual observation windows are provided at preset measurement points at 3m, 6m, and 12m along the propagation section pipeline, with equipment deployed outside the windows. A high-speed camera with a frame rate of 1500fps, with its lens directly facing the center of the viewing window, is used to accurately capture the transient flow field changes around the organism at the moment of the shock wave. The multiphysics data acquisition unit includes a high-speed data acquisition instrument, as well as pressure sensors, temperature sensors, and CO sensors arranged along the pipeline axis. The pressure sensors are respectively located at the end of the detonation section and at positions of 3m, 6m, and 12m in the propagation section, with a sampling frequency of 2MHz. The temperature and CO sensors are arranged at the same locations as the pressure sensors. An exhaust fan is connected to the end of the propagation section as an exhaust gas treatment unit to safely vent harmful gases from the pipeline after the explosion.

[0084] 4. During the system debugging phase, close all valves in the detonation section, turn on the vacuum pump to evacuate the detonation section, and after turning off the vacuum pump, let it stand for 10 minutes. If the vacuum pressure gauge reading does not drop significantly, it confirms that the airtightness of the detonation section meets the experimental requirements. Simultaneously debug the ignition unit, synchronization control unit, data acquisition unit, and high-speed camera to confirm that ignition triggering, data acquisition, and high-speed camera shooting can start synchronously, that the signal transmission of each sensor is normal, and that the high-speed camera has no frame loss or blurry images.

[0085] II. Preparation of Experimental Materials and Animals 1. Experimental Animals: SPF-grade male SD rats, aged 10-12 weeks and weighing 250±20g, were purchased from a qualified experimental animal breeding institution. Before the experiment, the rats were placed in a barrier environment for one week for acclimatization, with free access to food and water, maintaining a 12-hour circadian rhythm. They were fasted and deprived of water for 24 hours prior to the experiment. All physiological indicators, including baseline heart rate, blood pressure, and weight, were recorded in advance.

[0086] 2. Biological sample restraint device: A matrix-type integrated restraint cage is fabricated using 304 stainless steel, corresponding to... Figure 2 The restraint cage is a 3×3 matrix-type connected structure containing 9 independent and enclosed cage positions. It is divided into three layers, with 3 cage positions evenly distributed in each layer. The internal dimensions of a single cage position are 165mm long, 65mm wide, and 80mm high. The cage body is constructed using a mesh structure with main ribs of 4mm diameter, secondary ribs of 2mm diameter, and mesh aperture of 25mm. This structure effectively restrains rat movement without significantly obstructing shock wave propagation, while also providing sufficient impact resistance.

[0087] 3. Detection reagents and instruments: The methane gas used in the experiment has a purity of 99.99%, and the matching HE staining reagent, serum biochemical test kit, real-time fluorescence quantitative PCR kit, and Western blot test reagent are all of analytical grade; the detection instruments include a small animal X-ray machine, a small animal CT scanner, a fully automated biochemical analyzer, an optical microscope, a real-time fluorescence quantitative PCR instrument, a protein immunoblotting system, a non-invasive physiological parameter detector, and a 1500fps high-speed camera.

[0088] III. Experimental Group Setup The experimental rats were grouped using a random number table method, with a blank control group and an explosion experimental group, each containing 9 rats. All experimental groups were tested in triplicate to ensure the reliability of the experimental results.

[0089] The explosion experiment group was divided into subgroups according to three variable dimensions to fully cover different downhole explosion scenarios: 1. Concentration subgroups: 7.5% methane concentration group, 9.5% methane concentration group, and 11.5% methane concentration group are set up respectively, corresponding to typical scenarios in the lower explosion limit range, chemical equivalent concentration, and upper explosion limit range of methane; 2. Distance subgroups: 3m exposure group, 6m exposure group, and 12m exposure group are set up respectively, corresponding to the three preset measuring point positions of the distance detonation section within the propagation section; 3. Posture subgroups: The subgroups are divided into a prone group and a standing group, which correspond to the two stress postures of personnel in the mine, namely prone and standing.

[0090] The control group rats were kept in the same environment as the experimental group, but were not exposed to the blast impact. The rest of the procedures, such as anesthesia, blood collection, and testing, were exactly the same as those for the experimental group.

[0091] IV. Complete Experimental Procedure Step 1: Biological Sample Posture Constraint and Installation Rats in the experimental groups were placed in individual cages within a matrix-style conjoined restraint cage system, with one rat in each cage. The cage doors were sealed to stabilize the rats' range of movement and ensure they could not adjust their position independently during the explosion. For the supine group, the cage orientation was adjusted to ensure the rats remained prone with their heads facing the detonation section; for the standing group, the cage orientation was adjusted to ensure the rats remained standing with their torsos perpendicular to the bottom of the pipe. The loaded restraint cages were then fixed to pre-defined measuring points within the propagation section using stainless steel supports. All restraint cages in the same group were fixed to the same measuring point, corresponding to distances of 3m, 6m, and 12m from the detonation section, ensuring all rats in the group were exposed to a completely identical explosion environment.

[0092] Step 2: Explosion Environment Simulation and Synchronous Triggering Turn on the air compressor to thoroughly clean the propagation section pipeline, removing impurities before sealing the end of the propagation section. Evacuate the detonation section again to the preset vacuum level. Calculate the methane injection volume using the partial pressure method. Open the injection valve and methane cylinder to inject methane gas into the detonation section. Then, introduce clean air to atmospheric pressure and close the injection valve. Open the inlet and outlet recirculation valves and start the explosion-proof circulation pump to circulate and premix the gas mixture in the detonation section. Once the circulating gas volume reaches four times the volume of the detonation section cavity, close the circulation pump and circulation valves. Let the mixed gas stand for 20 minutes, and confirm that the mixed gas concentration has reached the preset experimental value using a methane concentration gauge. The high-energy igniter is triggered by the synchronous controller to ignite and detonate the mixed gas. At the same time, the high-speed data acquisition instrument and the high-speed camera with a frame rate of 1500fps are activated synchronously. The high-speed camera accurately captures the transient flow field changes around the rat at the moment of the shock wave action through the pipeline viewing window. The high-speed data acquisition instrument synchronously collects the real-time change data of shock wave overpressure, temperature and CO concentration at each measuring point, and fully records the physical parameters and flow field characteristics of the entire explosion process.

[0093] Step 3: Comprehensive Damage Assessment of Explosion Impact Injuries Immediately after the explosion, turn on the exhaust fan at the end of the propagation section to completely vent the harmful gases from the pipe. Quickly remove the restraint cage and rat, and conduct a comprehensive injury assessment in sequence: 1. Immediate injury assessment: Observe and record the number of surviving rats, the extent of burns on the skin and fur, limb movement, and level of consciousness as soon as possible. Use a non-invasive physiological testing instrument to detect the heart rate, respiratory rate, and blood pressure of the rats to complete the preliminary grading assessment of the degree of injury. 2. Imaging examination: After standardized anesthesia, surviving rats were subjected to X-ray examination and small animal CT scan in sequence to comprehensively observe the morphological changes of the rat's limb bones, chest lungs, and abdominal organs, and record the damage such as fractures, pulmonary effusion, and pleural and peritoneal effusions to obtain internal structural damage data in vivo. 3. Blood biochemistry test: Blood was collected from the abdominal aorta of rats, serum was separated, and the levels of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine, and lactate dehydrogenase in the serum were detected using a fully automated biochemical analyzer to assess the degree of damage to the liver, kidneys, and myocardium of rats from a functional perspective. 4. Histopathological examination: After blood collection, rats were euthanized humanely, and brain, heart, liver, lung, and kidney tissues were dissected and removed. First, gross morphological observation was performed, and the gross changes of organ congestion, edema, hemorrhage, and rupture were recorded. Then, the tissue samples were fixed with 4% paraformaldehyde, dehydrated, embedded, sectioned, and stained with hematoxylin and eosin (HE). The microscopic pathological changes of the tissues were observed under an optical microscope, and the degree of cell necrosis, inflammatory cell infiltration, hemorrhage, and edema were recorded. 5. Molecular biological detection: Rat lung and brain tissue samples were collected, and total RNA and total protein were extracted from the tissues. Real-time quantitative PCR was used to detect the mRNA expression levels of inflammatory factors and oxidative stress-related genes, and Western blot was used to detect the expression levels of apoptosis-related proteins. The molecular mechanism of blast injury was analyzed.

[0094] Step 4: Parallel Control Experiment under Multiple Operating Conditions After completing the single-group experiment, the connecting flange between the detonation section and the propagation section was disassembled, and a brand-new PTFE membrane sealing diaphragm was replaced. An air compressor was used to thoroughly clean the pipes in both the detonation and propagation sections to completely remove any explosive residues and condensates, eliminating any interference from the previous experiment. New experimental rats were used, and the entire process of sample installation, explosion triggering, and damage assessment was repeated. All subgroup experiments with different methane concentrations, different exposure distances, and different impact postures were performed, along with three parallel replicate experiments.

[0095] Step 5: Data Integration and Pattern Analysis Explosion physics parameters and biological damage quantification indicators were collected from all experimental groups. Statistical software was used to analyze the significant differences between groups. The differences in the degree of injury of rats under different methane concentrations, different exposure distances, and different impact postures were compared. A quantitative correlation model between shock wave overpressure, exposure distance, impact posture, and the degree of multi-organ damage in rats was established. The damage patterns and target organ characteristics of gas explosion shock injuries in coal mines were sorted out, and finally a standardized experimental evaluation system for gas explosion shock injuries in coal mines was formed.

[0096] V. Experimental Results 1. Explosion physical parameters: The 9.5% methane concentration group had the highest overpressure peak of the explosion shock wave, reaching 182 kPa at 6m, 126 kPa at 3m, and 91 kPa at 12m; the overpressure peaks of the 7.5% and 11.5% concentration groups were lower than those of the 9.5% concentration group, which is completely consistent with the combustion characteristics of gas explosion.

[0097] 2. Initial Immediate Injury Assessment Results: In the blank control group, rats showed no abnormalities and their vital signs were stable. In the 9.5% methane concentration group, the mortality rate of rats at 6m exceeded 70%, with surviving rats exhibiting 70% skin and fur burns, some areas showing charring, limb movement disorders, and loss of consciousness. Rats at 3m showed severe injury, with approximately 50% skin and fur burns and disordered vital signs. Rats at 12m showed moderate injury, with no obvious skin and fur burns, but exhibited rapid breathing and reduced activity. The overall injury severity in the standing group was significantly higher than that in the lying group, consistent with the biomechanical characteristics of shock wave propagation. Figure 3 The manifestations of damage to the body surface.

[0098] 3. Imaging and Gross Pathological Results: CT images of rats in the explosion experiment group showed diffuse pulmonary effusion and pleural effusion. Some rats exhibited rib fractures and long bone fractures of the limbs. X-ray examination clearly showed discontinuity in skeletal structure. Figure 5 , Figure 6 Imaging findings; gross anatomical examination revealed significant congestion, edema, and ecchymosis in the lungs, heart, liver, and other organs of the rats in the explosion experiment group, with focal ruptures in some organs. Figure 4 The gross morphological changes of the internal organs.

[0099] 4. Blood biochemistry and pathological test results: Compared with the blank control group, the serum liver function, kidney function, and myocardial injury-related indicators of rats in the explosion experimental group were significantly increased, and the increase was positively correlated with the peak value of the explosion overpressure. The indicators in the 6m position group showed the most significant increase. Figure 7 Changes in serum biochemical indicators; HE staining sections showed that the lung tissue of the rats in the explosion experimental group exhibited alveolar rupture, diffuse hemorrhage, edema, and a large number of inflammatory cell infiltrations. The myocardium, liver, kidney, and brain tissues all showed varying degrees of cell necrosis and pathological changes. The degree of damage was positively correlated with the peak value of the explosion overpressure.

[0100] 5. Transient flow field capture results: The 1500fps high-speed camera clearly captured the transient eddies formed on the surface of the rat and the trajectory of the shock wave front when the explosion shock wave propagated to each measuring point through the viewing window. The flow field changes were highly matched with the peak overpressure and propagation speed of the shock wave, which intuitively restored the dynamic process of the interaction between the shock wave and the organism, and provided a visual basis for the analysis of biomechanical damage mechanisms.

[0101] 6. Results of Pattern Analysis: Through correlation analysis of multi-dimensional data, the influence weights of three core factors—gas concentration, exposure distance, and impact posture—on the degree of damage to organisms were clarified. A quantitative correlation model between explosion physical parameters and the degree of biological damage was established, forming a complete experimental evaluation system covering explosion scenario simulation, damage classification, and mechanism analysis.

[0102] VI. Supplementary Implementation Examples This supplementary embodiment is used to verify the modular adaptability of the present invention. Except for the experimental pipeline splicing scheme, the other experimental materials, grouping, and operation steps are the same as those in the main embodiment above.

[0103] In this implementation example, the detonation section consists of two 1m pipe sections spliced ​​together, with a total length of 2m; the propagation section consists of 1m+2m+3m pipe sections spliced ​​together, with a total length of 6m, used to simulate gas explosion shock injury scenarios in short-distance roadways and chambers in coal mines. The experimental results stably obtain the propagation characteristics of shock waves and the corresponding biological damage patterns within short-distance roadways, verifying that this experimental method can flexibly adapt to the simulation needs of confined spaces in underground mines of different scales, thus expanding the applicability of the method.

[0104] In step S6, the statistical correlation analysis ultimately constructs a quantitative correlation model, which includes a single-factor core injury quantitative model, a multi-factor coupling modified quantitative correlation model, an organ-specific injury quantitative correlation model, and an injury severity grading quantitative determination model, as detailed below: Single-factor core injury quantification model: Using the peak overpressure of the explosion shock wave as the core injury-causing independent variable and the comprehensive damage index of the organism as the dependent variable, a linear-power function coupled core injury model is constructed by fitting large sample data obtained through the standardized experiments of this invention. The formula is as follows:

[0105] In the formula: It is an index of the overall degree of damage to an organism, with a value range of 0 to 100. The higher the value, the more severe the damage. The value represents the peak overpressure of the shock wave at the measuring point, expressed in kPa, and ranges from 0 to 500 kPa. , , The constants for model fitting are determined based on the experimental data from this invention. , , Model fit It exhibits extremely high statistical significance; Multi-factor Coupled Corrected Quantitative Correlation Model: Based on the core injury model, correction coefficients are introduced for three key working condition variables: methane concentration, exposure distance, and impact posture, to construct a multi-factor coupled, full-dimensional quantitative correlation model. The formula is as follows:

[0106] In the formula: The methane concentration correction factor was determined based on the energy release characteristics of methane explosion and the fitting of experimental data: when the methane volume fraction is 7.5%, When the volume fraction of methane is 9.5%, When the volume fraction of methane is 11.5%, ; The exposure distance correction factor was determined by fitting experimental data to the propagation attenuation characteristics of the shock wave within the tunnel: at an exposure distance of 3m, When the exposure distance is 6m, When the exposure distance is 12m, ; The impact posture correction coefficient is determined by fitting experimental data to the biomechanical characteristics of the interaction between the shock wave and the organism: In the supine position (prone position facing the shock wave), When standing (facing the shock wave vertically), ; Organ-specific damage quantitative correlation model: For the core target organs of gas explosion blast injury, specific quantitative correlation models between the degree of damage to each organ and the physical parameters of the explosion are constructed, as shown in the following formula:

[0107] In the formula: , which is the specific damage index of the nth target organ, where n corresponds to the five core target organs: lung, heart, liver, kidney, and brain. The damage index of each organ ranges from 0 to 100. , , The model fitting constants for the corresponding target organs are determined based on the imaging, biochemical, and pathological examination data of each organ obtained from the experiments of this invention, specifically as follows: lung: , , , ; heart: , , , ; liver: , , , ; kidney: , , , ; Cranium: , , , ; A quantitative assessment model for injury severity grading: Based on the comprehensive injury severity index D, combined with clinical injury grading standards and experimental validation results, a four-level quantitative grading standard for coal mine gas explosion impact injuries is constructed. No damage: The organism showed no visible damage, its vital signs were stable, and there were no abnormal changes in imaging, biochemistry, and pathological examinations. Minor injury: The organism had no burns on its body surface, its vital signs were basically stable, and only slight abnormalities in biochemical indicators were observed, with no obvious pathological morphological changes. Moderate injury: The organism experiences minor burns to the body surface, disordered vital signs, accompanied by significant abnormalities in biochemical indicators and pathological changes such as edema and hemorrhage in organs and tissues; Severe injury: The organism suffers extensive burns to its body surface, severe disturbances in vital signs, and severe pathological damage to multiple organs, resulting in a significantly increased mortality rate.

[0108] Based on the above experimental data, the quantitative correlation model constructed in this invention was fully verified, and the verification results are as follows: Core injury model validation: The measured peak overpressure of the shock wave at 6m in the 9.5% methane concentration group was 182 kPa. Substituting this into the single-factor core injury model, the comprehensive injury severity index D=78.6 was calculated, which perfectly matched the actual injury severity of the rats in this group (mortality rate exceeding 70%, severe damage to multiple organs). The measured overpressure at 3m was 126 kPa, and the calculated D=47.2 was consistent with the actual moderate to severe injury of the rats in this group. The measured overpressure at 12m was 91 kPa, and the calculated D=31.5 was completely consistent with the actual moderate injury of the rats in this group. The relative error between the model prediction and the actual injury severity was less than 8%, demonstrating extremely high prediction accuracy.

[0109] Validation of the multi-factor coupling model: Under 9.5% methane concentration, 6m exposure distance, and standing position, the model calculated D=78.6; under the same overpressure conditions, when switching to a supine position, the model calculated D=78.6×0.79=62.1, which perfectly matches the actual results that the injury degree of the standing group was significantly higher than that of the supine group in the experiment; Under 7.5% methane concentration, 6m exposure distance, and standing position, the measured peak overpressure was 112kPa, and the model calculated D=(0.326×112^1.142-2.185)×0.72=29.8, which is consistent with the experimental results of mild to moderate injury in this group of rats, fully validating the accuracy of the multi-factor correction coefficient.

[0110] Organ-specific model validation: At position 6m in the 9.5% methane concentration group, the lung-specific injury model yielded a D1=92.3, which perfectly matched the pathological damage results of diffuse alveolar rupture, severe hemorrhage and edema in the lungs of this group of rats; the heart-specific injury model yielded a D2=67.5, which was consistent with the experimental results of cardiomyocyte necrosis and significantly elevated serum myocardial enzymes in this group of rats. The correlation coefficients between the predicted values ​​of each organ model and the actual pathological injury scores were all greater than 0.92, demonstrating a very strong ability to accurately predict organ damage.

[0111] The above are merely preferred embodiments of the present invention and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should recognize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. An experimental method for assessing the impact injuries caused by gas explosions in underground coal mines, characterized by simulating and quantifying the impact damage to organisms caused by gas explosions in confined spaces of underground coal mines, and incorporating the following features: Includes the following steps: S1: Construct a roadway explosion test system. The system includes a modular rectangular test pipeline consisting of a detonation section and a propagation section that are sequentially sealed and connected. It is equipped with a gas distribution unit, an ignition unit, a synchronization control unit, and a multi-physics field data acquisition unit. By adjusting the combined length of the pipeline between the detonation section and the propagation section, the system simulates the confined roadway space of coal mines at different scales. The detonation section and the propagation section are isolated by a breakable sealing partition. S2: Standardized preprocessing and posture constraint of biological samples. Experimental rats are grouped and placed in matrix-type conjoined constraint cages. The constraint cages are equipped with multiple independent and closed cage positions to form spatial constraints on individual rats to fix their impact posture. The constraint cages carrying rats are fixed at preset measuring point positions in the propagation section pipe. The impact posture of the rats is switched by adjusting the installation orientation of the constraint cages. S3: Standardized simulation and synchronous triggering of gas explosion environment. After the airtightness of the detonation section is checked, a vacuum is drawn. A methane-air mixture of a preset concentration is introduced into the detonation section by the partial pressure method. The circulation unit is turned on to uniformly premix the mixture and let it stand. The ignition unit is triggered by the synchronous control unit to detonate the mixture. At the same time, the multi-physics field data acquisition unit is triggered to synchronously collect the physical and mechanical parameters of the entire explosion process in the pipeline. S4: Comprehensive assessment of blast impact injury. After the explosion, the harmful gas in the pipeline was evacuated. After the rat was removed, an immediate initial assessment of the injury was completed. Then, imaging tests, blood biochemistry tests, histopathological tests and molecular biological tests were carried out in sequence to obtain multi-organ and multi-dimensional quantitative indicators of injury in rats. S5: Multi-condition control experiment, replace the sealing baffle between the detonation section and the propagation section, clean the explosion residue in the pipeline, repeat steps S2 to S4, and carry out multiple sets of parallel control experiments under different methane concentrations, different measuring point distances, and different impact postures. S6: Damage pattern analysis and evaluation system construction. Statistical correlation analysis is conducted on the explosion physics and mechanics parameters and biological damage quantitative indicators collected from each group of experiments to establish the mapping relationship between explosion exposure conditions and the degree of biological damage, forming a standardized experimental evaluation system for gas explosion impact injuries in coal mines.

2. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, The rectangular experimental pipeline is made of rectangular steel pipe with an inner cross-sectional dimension of 500mm×500mm and a wall thickness of 2cm. The detonation section and the propagation section are both spliced ​​together from multiple sections of pipe with a length of 1m, 2m, 3m or 4m, and the splice is fixedly connected by a sealing flange. The breakable sealing partition is made of PTFE film and is clamped and fixed between the flanges connecting the detonation section and the propagation section.

3. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, The matrix-type integrated restraint cage is a 3×3 matrix-type integrated steel cage containing 9 independent and enclosed cage positions. The cage positions are divided into three layers, with 3 cage positions evenly arranged in each layer. The internal dimensions of a single cage position are 165mm in length, 65mm in width, and 80mm in height. The cage body is made of a grid structure with a main rib diameter of 4mm, a secondary rib diameter of 2mm, and a grid aperture of 25mm.

4. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S2, the impact posture of the rats is switched by adjusting the installation position of the restraint cage. The impact posture includes a standing posture that simulates the standing position of a person in an underground mine, and a lying posture that simulates the prone position of a person in an underground mine. In the same group of experiments, the impact posture of all rats in the restraint cage is kept consistent.

5. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S2, the preset measuring point positions in the propagation section pipe include position 1, which is 3m away from the ignition end of the detonation section; position 2, which is 6m away from the ignition end of the detonation section; and position 3, which is 12m away from the ignition end of the detonation section. In the same set of experiments, the entire constraint cage is fixed at a single preset measuring point position, and different sets of experiments correspond to different preset measuring point positions.

6. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S3, the preset concentration of methane-air mixture includes a lower limit concentration mixture with a methane volume fraction of 7.5%, a stoichiometric concentration mixture with a methane volume fraction of 9.5%, and an upper limit concentration mixture with a methane volume fraction of 11.5%. A single concentration of methane-air mixture is used in the same group of experiments, and different concentrations of methane-air mixture are used in different groups of experiments.

7. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S3, when the circulation unit premixes the gas mixture uniformly, the volume of the circulating gas is not less than three times the volume of the inner cavity of the detonation section; after the premixing is completed, the circulation unit is turned off, and the gas mixture is left to stand for no less than 15 minutes before ignition and detonation are triggered.

8. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S3, the multiphysics data acquisition unit includes multiple pressure sensors, temperature sensors, and CO sensors arranged along the pipeline axis, as well as a high-speed data acquisition instrument; when the synchronous control unit triggers ignition, it also triggers the high-speed data acquisition instrument to synchronously acquire real-time change data of shock wave overpressure, ambient temperature, and CO concentration at each measuring point in the pipeline at a sampling frequency of not less than 1MHz.

9. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S4, the immediate initial injury assessment includes observing and recording the survival status, external body surface damage, and behavioral and consciousness status of the experimental rats, while simultaneously monitoring the rats' heart rate, respiration, blood pressure, and other vital signs in real time to complete the preliminary assessment of the degree of damage from the blast impact injury.

10. The experimental method for treating gas explosion shock injuries in coal mines according to claim 1, characterized in that, In step S4, the imaging examination includes one or more of X-ray examination, ultrasound examination, CT examination, and MRI examination to perform in vivo scanning examination of the rat's brain, thoracic cavity, abdominal organs and skeletal structure to obtain morphological damage imaging data of the rat's organs and bones.

Images