A method for assessing gas risk in shield earth bunker based on neon gas simulation of gas escape

Abstract

The present invention discloses a shield earth bunker gas risk assessment method based on neon gas simulation gas escape, the method comprising the following steps: 1. constructing a neon gas simulation gas escape test device; 2. using the neon gas simulation gas escape test device to simulate the shield earth bunker gas escape process; 3. according to the neon gas concentration value data at different positions in the simulated earth bunker obtained by the simulation test, combined with the neon gas escape law, using the LSSVM regressor to construct a gas hazard point inversion model; 4. based on the gas risk classification standard, combined with the gas hazard point inversion model, assess the shield earth bunker gas risk level. The neon gas simulation gas escape test device of the present invention can accurately simulate the process of stratum gas overflow at different flow rates and different positions, the test process is easy to operate, highly safe, and can achieve the purpose of assessing the gas risk in the earth bunker, laying a foundation for the safe construction of gas water conservancy tunnels.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel engineering, and in particular relates to a shield earth bunker gas risk assessment method based on neon gas simulation gas escape. Background Art

[0002] In recent years, as my country has made significant progress in the field of water conservancy infrastructure construction, the shield method has gradually become the preferred method for water conservancy tunnel construction. However, during the shield construction process, special geological conditions such as high gas may be encountered, which pose a potential threat to the safe construction of water conservancy tunnels. Due to the complex construction conditions, the durability requirements of gas sensors are very high. Usually, a gas sensor is arranged at a fixed position in the shield soil bin to realize real-time monitoring of the gas in the soil bin. Due to the limited number of sensors, it cannot fully reflect the gas concentration in the entire soil bin, especially the local gas risk cannot be accurately assessed; it can also be evaluated by simulating the gas escape test in the field soil bin. However, the existing simulation test device directly uses methane gas for simulation, the test safety is poor, accidents are prone to occur, and it is impossible to simulate the gas overflow of the formation under various working conditions, and it is also impossible to accurately assess the gas risk in the soil bin. Therefore, a shield soil bin gas risk assessment method based on neon gas simulation gas escape should be provided. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a shield earth silo gas risk assessment method based on neon gas simulation of gas escape in response to the deficiencies in the above-mentioned prior art. The method has a reasonable design and can accurately simulate the process of stratum gas overflow at different flow rates and different positions using a neon gas simulation gas escape test device. The test process is easy to operate and has high safety. It can achieve the purpose of assessing the gas risk in the earth silo and lay the foundation for the safe construction of gas and water conservancy tunnels.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a shield earth bunker gas risk assessment method based on neon gas simulation gas escape, characterized in that: the method comprises the following steps:

[0005] Step 1: Construct a neon gas simulation gas escape test device:

[0006] The neon gas simulation gas escape test device comprises a simulated shield soil bin, a simulated stratum arranged in the simulated shield soil bin, and a plurality of conduits arranged in layers in the simulated stratum, as well as a high-pressure neon gas tank connected to the exposed end of the conduit and a high-precision neon gas detector for real-time monitoring of the neon concentration in the simulated shield soil bin. The simulated shield soil bin comprises an arc-shaped cylinder horizontally placed on a base and an arc-shaped top cover snap-fittedly mounted on the top of the arc-shaped cylinder, and a left circular sealing plate and a right circular sealing plate respectively arranged at both ends of the arc-shaped cylinder, and a plurality of conduit passing holes are opened on the left circular sealing plate. The construction process of the neon gas simulation gas escape test device comprises:

[0007] Step 101, when the arc-shaped top cover is opened, a plurality of the high-precision neon gas detectors and a pressure detector are arranged on the inner side of the right circular cover plate, the plurality of the high-precision neon gas detectors are arranged at intervals on the vertical center line of the right circular cover plate, and the plurality of the high-precision neon gas detectors and the pressure detector are connected to the input end of the controller;

[0008] Step 102, with the arc-shaped top cover open, simulated strata are arranged in layers in the simulated shield soil bin body, the left side of the simulated strata is closely attached to the inner side of the left circular sealing plate, the cavity formed between the right side of the simulated strata and the right circular sealing plate is the simulated soil bin, the right side of the simulated stratum is the simulated tunnel face, and a plurality of conduits are arranged in layers in the simulated stratum, the exposed ends of the conduits pass through the conduit through holes and extend to the outside of the left circular sealing plate, and the distance between the hidden ends of the conduits and the simulated tunnel face is the set escape horizontal distance;

[0009] Step 103, installing the arc-shaped top cover to make the simulated shield soil bin body sealed, and then using a vacuum pump to adjust the gas pressure in the simulated soil bin, and when the pressure detector detects in real time that the gas pressure in the simulated soil bin is equal to the gas pressure setting value, turning off the vacuum pump;

[0010] Step 2: using the neon gas simulation gas escape test device to simulate the gas escape process of the shield earth bunker, the specific process includes:

[0011] Step 201, labeling a plurality of conduits as a first conduit, a second conduit, ... an N-1th conduit and an Nth conduit from bottom to top, wherein N is a positive integer;

[0012] Step 202, connect the gas delivery pipe of the high-pressure neon gas tank to the exposed end of the first conduit, open the flow control valve, use the flow control valve to adjust the set flow rate of the high-pressure neon gas multiple times, fill the simulated formation with high-pressure neon gas, and collect the dissipation data of the high-pressure neon gas at different set flow rates. The specific process of filling the simulated formation with high-pressure neon gas each time is as follows:

[0013] When the duration of filling the simulated stratum with high-pressure neon gas reaches the set duration of filling, the flow control valve is closed, and the high-pressure neon gas will escape through the simulated stratum into the simulated soil bin, realizing the process of simulating gas overflowing from the excavated stratum into the shield soil bin. After the escape duration of the high-pressure neon gas reaches the set escape duration, the neon gas concentration values ​​at different positions in the simulated soil bin are monitored in real time by a plurality of the high-precision neon gas detectors, and transmitted to the controller in real time;

[0014] Step 203, using an air pump to extract neon gas in the simulated soil bin until the multiple high-precision neon gas detectors all show that the neon gas concentration in the simulated soil bin is 0, and then using an air pump to fill air into the simulated soil bin, and when the pressure detector detects in real time that the gas pressure in the simulated soil bin is equal to the gas pressure setting value, the air pump is turned off;

[0015] Step 204, disconnecting the gas delivery pipe of the high-pressure neon gas tank from the exposed end of the first conduit, and sequentially connecting the gas delivery pipe of the high-pressure neon gas tank to the second conduit, ... the N-1th conduit and the Nth conduit, and repeating the process of filling the simulated stratum with high-pressure neon gas in steps 202 to 203 for multiple times until the N conduits arranged at different heights from bottom to top complete the simulation of the gas escape process;

[0016] Step 205, collating the test data, analyzing the data changes of the neon concentration values ​​at different positions in the simulated soil bin, and obtaining the neon emission law;

[0017] Step 3: Based on the neon concentration data at different positions in the simulated soil bin obtained from the simulation test and combined with the neon emission law, a gas hazard point inversion model is constructed using the LSSVM regressor. Based on the gas risk classification standard and combined with the gas hazard point inversion model, the gas risk level of the shield soil bin is evaluated.

[0018] The above-mentioned shield earth silo gas risk assessment method based on neon gas simulation gas escape is characterized in that: in step 102, the value range of the set escape horizontal distance is 20cm~30cm.

[0019] The above-mentioned shield earth bunker gas risk assessment method based on neon gas simulation gas escape is characterized in that: in step 103 and step 203, the gas pressure setting value ranges from 0.5MPa to 0.8MPa.

[0020] The above-mentioned shield earth bunker gas risk assessment method based on neon gas simulation gas escape is characterized in that: in step 3, before using the LSSVM regressor to construct the gas hazard point inversion model, it is necessary to first use the gas diffusion tube method to measure the diffusion coefficient D of neon gas in the air in the laboratory. Ne and the diffusion coefficient of methane in air D CH4 ; Then according to the formula Get C CH4 =1.22C Ne , where D Ne =0.18, D CH4 =0.22, C Ne is the neon concentration measured by a high-precision neon detector, C CH4 is the estimated value of methane concentration.

[0021] The above-mentioned shield earth bunker gas risk assessment method based on neon gas simulation gas leakage is characterized in that: multiple high-precision neon gas detectors are marked from bottom to top as detector No. 1, detector No. 2,... detector No. M-1 and detector No. M, where M is a positive integer, and multiple high-precision neon gas detectors are all connected to the input end of the controller.

[0022] The above-mentioned shield earth bunker gas risk assessment method based on neon gas simulation gas escape is characterized in that a pressure gauge is installed on the gas transmission pipe.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. The present invention constructs a neon gas simulation gas escape test device, which can accurately simulate the process of formation gas overflow at different flow rates and different positions. By real-time monitoring of the gas concentration at different positions, an accurate data basis is provided for analysis, thereby realizing the safe simulation of gas formation tests indoors, and can be used for various gas formation test studies.

[0025] 2. The present invention constructs a gas hazard point inversion model by utilizing the collected data and gas escape laws, which can more accurately predict and locate possible gas hazard areas. Combining the gas risk classification standards and the gas concentration data obtained by the inversion model, the gas risk level in the soil bin can be quantitatively evaluated, thereby facilitating the adoption of corresponding prevention and response measures.

[0026] 3. The assessment method of the present invention does not rely on specific geological conditions, has strong environmental adaptability, and can be widely used in shield construction risk assessment under different geological conditions. It can effectively identify and assess gas risks during tunnel construction, thereby improving the safety of the construction process and reducing the possibility of accidents.

[0027] 4. The test process of the present invention is easy to operate, highly safe, and easy to promote and apply.

[0028] In summary, the present invention is reasonably designed, and the neon gas simulation gas escape test device can accurately simulate the process of formation gas overflow at different flow rates and different positions. The test process is easy to operate and has high safety. It can achieve the purpose of evaluating the gas risk in the soil silo and lay the foundation for the safe construction of gas and water conservancy tunnels.

[0029] The present invention is further described in detail below through the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure is a flow chart of the evaluation method of the present invention.

[0031] Figure 2 It is a structural schematic diagram of the neon gas simulation gas escape test device of the present invention.

[0032] Figure 3 The diagram is a schematic diagram of the connection structure of the simulated shield soil bin body, base, high-precision neon gas detector and pressure detector after the arc-shaped top cover is removed in the present invention.

[0033] Description of reference numerals:

[0034] 1-1—arc-shaped cylinder; 1-2—left circular sealing plate; 1-3—right circular sealing plate;

[0035] 1-4—arc-shaped roof; 2—simulated stratum; 2-1—simulated tunnel face;

[0036] 3—duct; 4—high-precision neon gas detector; 5—simulated soil bin;

[0037] 6—base; 7—air pump; 8—pressure detector;

[0038] 9—high-pressure neon gas tank; 10—gas transmission pipe; 11—pressure gauge;

[0039] 12—Flow control valve. DETAILED DESCRIPTION

[0040] like Figure 1 , Figure 2 and Figure 3 A shield earth bunker gas risk assessment method based on neon gas simulation gas escape is shown, the method comprising the following steps:

[0041] Step 1: Construct a neon gas simulation gas escape test device:

[0042] The neon gas simulation gas escape test device comprises a simulated shield soil bin, a simulated stratum 2 arranged in the simulated shield soil bin, and a plurality of conduits arranged in layers in the simulated stratum 2, as well as a high-pressure neon gas tank 9 for connecting to the exposed end of the conduit and a high-precision neon gas detector 4 for real-time monitoring of the neon concentration in the simulated shield soil bin. The simulated shield soil bin comprises an arc-shaped cylinder 1-1 horizontally placed on a base 6 and an arc-shaped top cover 1-4 snap-fitted and installed on the top of the arc-shaped cylinder 1-1, as well as a left circular sealing plate 1-2 and a right circular sealing plate 1-3 respectively arranged at both ends of the arc-shaped cylinder 1-1, and a plurality of conduit passing holes are opened on the left circular sealing plate 1-2. The construction process of the neon gas simulation gas escape test device comprises:

[0043] Step 101, when the arc-shaped top cover 1-4 is opened, a plurality of the high-precision neon gas detectors 4 and a pressure detector 8 are arranged on the inner side of the right circular cover 1-3, and the plurality of the high-precision neon gas detectors 4 are arranged at intervals on the vertical center line of the right circular cover 1-3, and the plurality of the high-precision neon gas detectors 4 and the pressure detector 8 are all connected to the input end of the controller;

[0044] Step 102, with the arc-shaped top cover 1-4 opened, simulated strata 2 are layered in the simulated shield soil bin body, the left side of the simulated stratum 2 is closely attached to the inner side of the left circular cover 1-2, the cavity formed between the right side of the simulated stratum 2 and the right circular cover 1-3 is the simulated soil bin 5, the right side of the simulated stratum 2 is the simulated tunnel face 2-1, and a plurality of conduits are layered in the simulated stratum 2, the exposed ends of the conduits pass through the conduit through holes and extend to the outside of the left circular cover 1-2, and the distance between the hidden ends of the conduits and the simulated tunnel face 2-1 is the set escape horizontal distance;

[0045] Step 103, installing the arc-shaped top cover 1-4 to make the simulated shield soil bin body sealed, and then using the vacuum pump 7 to adjust the gas pressure in the simulated soil bin 5, and when the pressure detector 8 detects in real time that the gas pressure in the simulated soil bin 5 is equal to the gas pressure setting value, the vacuum pump 7 is turned off;

[0046] Step 2: using the neon gas simulation gas escape test device to simulate the gas escape process of the shield earth bunker, the specific process includes:

[0047] Step 201, labeling a plurality of conduits from bottom to top as a first conduit 3-1, a second conduit 3-2, ... an N-1th conduit 3-3 and an Nth conduit 3-4, wherein N is a positive integer;

[0048] Step 202, connect the gas delivery pipe 10 of the high-pressure neon gas tank 9 to the exposed end of the first conduit 3-1, open the flow control valve 12, use the flow control valve 12 to adjust the set flow rate of the high-pressure neon gas for multiple times, fill the simulated formation 2 with high-pressure neon gas, and collect the dissipation data of the high-pressure neon gas at different set flow rates. The specific process of filling the simulated formation 2 with high-pressure neon gas each time is as follows:

[0049] When the duration of filling the simulated stratum 2 with high-pressure neon gas reaches the set duration of filling, the flow control valve 12 is closed, and the high-pressure neon gas will escape through the simulated stratum 2 into the simulated soil bin 5, realizing the process of simulating gas overflowing from the excavated stratum into the shield soil bin. After the escape duration of the high-pressure neon gas reaches the set escape duration, the neon gas concentration values ​​at different positions in the simulated soil bin 5 are monitored in real time by a plurality of the high-precision neon gas detectors 4, and transmitted to the controller in real time;

[0050] Step 203, using the vacuum pump 7 to extract the neon gas in the simulated soil bin 5 until the multiple high-precision neon gas detectors 4 all show that the neon gas concentration in the simulated soil bin 5 is 0, and then using the vacuum pump 7 to fill the simulated soil bin 5 with air, and when the pressure detector 8 detects in real time that the gas pressure in the simulated soil bin 5 is equal to the gas pressure setting value, the vacuum pump 7 is turned off;

[0051] Step 204, disconnect the gas delivery pipe 10 of the high-pressure neon gas tank 9 from the exposed end of the first conduit 3-1, and sequentially connect the gas delivery pipe 10 of the high-pressure neon gas tank 9 to the second conduit 3-2, ... the N-1th conduit 3-3 and the Nth conduit 3-4, and repeat the process of filling the simulated stratum 2 with high-pressure neon gas in steps 202 to 203 for multiple times until the N conduits arranged at different heights from bottom to top complete the simulation of the gas escape process;

[0052] Step 205, collating the test data, analyzing the data changes of the neon concentration values ​​at different positions in the simulated soil bin 5, and obtaining the neon emission law;

[0053] Step three, based on the neon concentration data at different positions in the simulated soil bin 5 obtained from the simulation test and combined with the neon emission law, a gas hazard point inversion model is constructed using the LSSVM regressor. Based on the gas risk classification standard and combined with the gas hazard point inversion model, the gas risk level of the shield soil bin is evaluated.

[0054] In this embodiment, in step 102, the setting range of the dissipation horizontal distance is 20 cm to 30 cm.

[0055] In this embodiment, in step 103 and step 203, the gas pressure setting value ranges from 0.5 MPa to 0.8 MPa.

[0056] In this embodiment, in step 3, before using the LSSVM regressor to construct the gas hazard point inversion model, it is necessary to first use the gas diffusion tube method to measure the diffusion coefficient D of neon in the air in the laboratory. Ne and the diffusion coefficient of methane in air D CH4 ; Then according to the formula Get C CH4 =1.22C Ne , where D Ne =0.18, D CH4 =0.22, C Ne is the neon concentration measured by the high-precision neon detector 4, C CH4 is the estimated value of methane concentration.

[0057] In this embodiment, the multiple high-precision neon gas detectors 4 are marked as detector No. 1, detector No. 2, ... detector No. M-1 and detector No. M from bottom to top, where M is a positive integer, and the multiple high-precision neon gas detectors 4 are all connected to the input end of the controller.

[0058] In this embodiment, a pressure gauge 11 is installed on the gas delivery pipe 10 .

[0059] In this embodiment, the number of the high-precision neon gas detectors 4 is seven, and the seven high-precision neon gas detectors 4 are marked from bottom to top as detector No. 1, detector No. 2, detector No. 3, detector No. 4, detector No. 5, detector No. 6 and detector No. 7. The data of the entire experimental process is recorded in the following table:

[0060]

[0061]

[0062]

[0063] By simulating the process of filling the simulated stratum 2 with high-pressure neon gas for many times, the purpose of simulating the gas escape process at different heights can be achieved. By adjusting the set flow rate of the high-pressure neon gas by using the flow control valve 12 for many times, the escape data of the high-pressure neon gas at different set flow rates can be collected. The neon gas simulation gas escape test device is easy to operate, has high test accuracy, stable performance, safety and reliability, and is easy to promote and apply.

[0064] In this embodiment, in step three, based on the gas risk classification standard and combined with the gas hazard point inversion model, the gas risk level of the shield soil bin is evaluated. When the gas concentration is less than 0.3%, the risk level is Level I; when the gas concentration range is 0.3%-0.6%, the risk level is Level II; when the gas concentration range is 0.6%-1.0%, the risk level is Level IIIA; when the gas concentration range is 1.0%-1.5%, the risk level is Level IIIB; when the gas concentration is greater than 1.5%, the risk level is Level IV.

[0065] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape, characterized in that: The method comprises the following steps: Step 1: Construct a neon gas simulation gas escape test device: The neon gas simulation gas emission test device comprises a simulated shield soil bin, a simulated stratum (2) arranged in the simulated shield soil bin, and a plurality of conduits arranged in layers in the simulated stratum (2), as well as a high-pressure neon gas tank (9) connected to the exposed end of the conduit and a high-precision neon gas detector (4) for real-time monitoring of the neon concentration in the simulated shield soil bin. The simulated shield soil bin comprises an arc-shaped cylinder (1-1) horizontally placed on a base (6), an arc-shaped top cover (1-4) snap-fitted and mounted on the top of the arc-shaped cylinder (1-1), and a left circular sealing plate (1-2) and a right circular sealing plate (1-3) respectively arranged at both ends of the arc-shaped cylinder (1-1), and a plurality of conduit passing holes are opened on the left circular sealing plate (1-2). The construction process of the neon gas simulation gas emission test device comprises: Step 101, when the arc-shaped top cover (1-4) is opened, a plurality of the high-precision neon gas detectors (4) and a pressure detector (8) are arranged on the inner side surface of the right circular cover (1-3), the plurality of the high-precision neon gas detectors (4) are arranged at intervals on the vertical center line of the right circular cover (1-3), and the plurality of the high-precision neon gas detectors (4) and the pressure detector (8) are connected to the input end of the controller; Step 102: When the arc-shaped top cover (1-4) is opened, a simulated stratum (2) is arranged in layers in the simulated shield soil bin, the left side surface of the simulated stratum (2) is tightly attached to the inner side surface of the left circular sealing plate (1-2), the cavity formed between the right side surface of the simulated stratum (2) and the right circular sealing plate (1-3) is the simulated soil bin (5), the right side surface of the simulated stratum (2) is the simulated tunnel face (2-1), and a plurality of conduits are arranged in layers in the simulated stratum (2), the exposed ends of the conduits pass through the conduit through holes and extend to the outside of the left circular sealing plate (1-2), and the distance between the hidden ends of the conduits and the simulated tunnel face (2-1) is a set escape horizontal distance; Step 103, installing the arc-shaped top cover (1-4) to make the simulated shield soil bin body in a sealed state, and then using an air pump (7) to adjust the gas pressure in the simulated soil bin (5), and when the pressure detector (8) detects in real time that the gas pressure in the simulated soil bin (5) is equal to the gas pressure setting value, the air pump (7) is turned off; Step 2: using the neon gas simulation gas escape test device to simulate the gas escape process of the shield earth bunker, the specific process includes: Step 201, labeling a plurality of conduits from bottom to top as a first conduit (3-1), a second conduit (3-2), ... an N-1th conduit (3-3), and an Nth conduit (3-4), wherein N is a positive integer; Step 202, connect the gas delivery pipe (10) of the high-pressure neon gas tank (9) to the exposed end of the first conduit (3-1), open the flow control valve (12), adjust the set flow rate of the high-pressure neon gas by using the flow control valve (12) for multiple times, fill the simulated formation (2) with high-pressure neon gas, collect the dissipation data of the high-pressure neon gas at different set flow rates, and the specific process of filling the simulated formation (2) with high-pressure neon gas each time is as follows: When the duration of filling the simulated stratum (2) with high-pressure neon gas reaches the set duration of filling, the flow control valve (12) is closed, and the high-pressure neon gas will escape through the simulated stratum (2) into the simulated soil bin (5), thus simulating the process of gas overflowing from the excavated stratum into the shield soil bin. When the duration of the high-pressure neon gas escape reaches the set duration of the escape, the neon gas concentration values ​​at different positions in the simulated soil bin (5) are monitored in real time by a plurality of the high-precision neon gas detectors (4), and are transmitted to the controller in real time. Step 203, using the vacuum pump (7) to extract the neon gas in the simulated soil bin (5) until the plurality of high-precision neon gas detectors (4) all display that the neon gas concentration in the simulated soil bin (5) is 0, then using the vacuum pump (7) to fill the simulated soil bin (5) with air, and when the pressure detector (8) detects in real time that the gas pressure in the simulated soil bin (5) is equal to the gas pressure setting value, the vacuum pump (7) is turned off; Step 204, disconnecting the gas delivery pipe (10) of the high-pressure neon gas tank (9) from the exposed end of the first conduit (3-1), and sequentially connecting the gas delivery pipe (10) of the high-pressure neon gas tank (9) to the second conduit (3-2), ... the N-1th conduit (3-3) and the Nth conduit (3-4), and repeating the process of filling the simulated stratum (2) with high-pressure neon gas in steps 202 to 203 for multiple times until the N conduits arranged at different heights from bottom to top have completed the simulation of the gas escape process; Step 205, collating the test data, analyzing the data changes of the neon concentration values ​​at different positions in the simulated soil bin (5) obtained by collection, and obtaining the neon emission law; Step 3: Based on the neon concentration data at different positions in the simulated soil bin (5) obtained from the simulation test and in combination with the neon emission law, a gas hazard point inversion model is constructed using an LSSVM regressor. Based on the gas risk classification standard and in combination with the gas hazard point inversion model, the gas risk level of the shield soil bin is evaluated.

2. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape according to claim 1, characterized in that: In step 102, the setting range of the dissipation horizontal distance is 20 cm to 30 cm.

3. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape according to claim 1, characterized in that: In step 103 and step 203, the gas pressure setting value ranges from 0.5 MPa to 0.8 MPa.

4. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape according to claim 1, characterized in that: In step 3, before using the LSSVM regressor to build the gas hazard point inversion model, it is necessary to first use the gas diffusion tube method to measure the diffusion coefficient D of neon in the air in the laboratory. Ne and the diffusion coefficient of methane in air D CH4 ; Then according to the formula Get C CH4 =1.22C Ne , where D Ne =0.18, D CH4 =0.22, C Ne is the neon concentration measured by the high-precision neon detector (4), C CH4 is the estimated value of methane concentration.

5. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape according to claim 1, characterized in that: The plurality of high-precision neon gas detectors (4) are marked from bottom to top as detector No. 1, detector No. 2, ... detector No. M-1 and detector No. M, wherein M is a positive integer. The plurality of high-precision neon gas detectors (4) are all connected to the input end of the controller.

6. A shield earth bunker gas risk assessment method based on neon gas simulation gas escape according to claim 1, characterized in that: A pressure gauge (11) is installed on the gas delivery pipe (10).

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