Method and system for detecting shield stratum disturbance based on cosmic ray muon, equipment and medium

Abstract

The invention discloses a method, a system, equipment and a medium for detecting shield stratum disturbance based on cosmic ray muons, which are used for respectively measuring muon information on the earth surface and underground of a shield construction area, and can be used for detecting the attenuation condition after the muons penetrate through the stratum. And calculating the average stratum density on each muon track according to the muon flux attenuation information. The stratum disturbance in the track direction is evaluated by comparing the stratum average density variable quantity of the same monitoring point position in the same track direction when excavation is just conducted and after excavation is conducted for a period of time, and if the stratum average density variable quantity in all the track directions is smaller than a preset threshold value, it is judged that no disturbance exists in the stratum; according to the method, the stratum disturbance can be accurately and visually detected, the method is not limited by the surface environment, the applicability is higher, the disturbance condition of the stratum above the whole tunnel can be detected, the detection range is larger, and nondestructive detection and disturbance early warning on the upper stratum during shield construction are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of shield stratum disturbance detection, and in particular to a method and system, electronic equipment and computer-readable storage medium for detecting shield stratum disturbance based on cosmic ray muons. Background Art

[0002] With the acceleration of urbanization, underground space development has become an important way to solve the bottleneck of urban development. Shield construction, with its advantages of high efficiency, safety, and suitability for complex geological conditions, occupies a core position in the construction of large-scale infrastructure such as subways, tunnels, and underground integrated pipe corridors. However, the shield tunneling process will inevitably cause disturbances to the overlying strata, which is mainly manifested in the push and squeeze of the shield and the shear friction of the shield shell, which will redistribute the stratum stress, cause surface settlement, foundation pit instability and other problems. In order to ensure construction safety, it is necessary to detect stratum disturbance. Traditional stratum disturbance detection technologies, such as surface settlement observation, drilling measurement of stratum displacement, groundwater level monitoring, and local soil sampling and analysis, have revealed the laws of stratum disturbance to a certain extent, but they also have certain limitations. Specifically, although surface subsidence observations are intuitive, they lack direct evidence of changes within the strata; although drilling measurements can penetrate deep into the strata, they damage the stratum structure, are costly, and have sparse monitoring points; groundwater level monitoring is greatly affected by hydrogeological conditions and is difficult to accurately reflect construction disturbances; local soil sampling has problems such as poor timeliness and lack of representativeness.

[0003] At present, in order to overcome the shortcomings of traditional ground disturbance detection methods, the industry has explored a variety of new monitoring technologies, including analysis methods based on reference point measurement data, micro-motion detection technology, and soil pressure monitoring systems. For example, patent CN115980843A discloses a non-destructive detection method for ground disturbance, which first detects the changes in the deep soil when the shield machine passes through by finding reference points around the construction area, and then uses this to infer the state of the deep soil in the construction area. However, when the geological conditions in the construction area are inconsistent with the reference points, the detection results are inaccurate, and this method is not completely non-destructive detection, and drilling is still required to determine whether the formation is deformed; in addition, patent CN113156491A discloses a shield ground disturbance detection method, which obtains construction ground wave velocity data by performing micro-motion detection before and after the construction of the shield target section, calculates the wave velocity change rate and determines the ground disturbance situation, but, Its application is limited by specific environmental conditions, especially in areas such as water areas or densely populated buildings where it is difficult to deploy micro-motion arrays, and micro-motion detection cannot be performed; in addition, patent CN117345203A discloses a method for monitoring the disturbance of pile foundations caused by a shield machine passing through an existing building. The method involves drilling holes at the points to be monitored, arranging a group of earth pressure monitoring devices vertically in the holes, and then backfilling the holes. When the shield machine moves to the area to be monitored, the stratum disturbance displacement is inferred based on the measured internal soil pressure value. However, this monitoring method requires at least one week after the monitoring device is buried before measurement can begin. The long waiting time affects the construction progress, and the soil pressure data at a single monitoring point is difficult to reflect the stratum disturbance in the construction area. Summary of the invention

[0004] The present invention provides a method and system for detecting stratum disturbance of a shield machine based on cosmic ray muons, an electronic device, and a computer-readable storage medium, which can accurately and intuitively detect stratum disturbance, are not restricted by the surface environment, have stronger applicability, and can also detect the disturbance of the stratum above the entire tunnel, with a larger detection range, thus realizing non-destructive detection and disturbance warning of the upper stratum during shield construction, and providing important guarantee for construction safety.

[0005] According to one aspect of the present invention, a method for detecting shield stratum disturbance based on cosmic ray muons is provided, comprising the following contents:

[0006] Obtaining the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the muon track direction and the muon flux in each track direction;

[0007] The underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring points during the shield construction are obtained respectively;

[0008] Based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, the first muon survival rate in each track direction is calculated; based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point, the second muon survival rate in each track direction is calculated;

[0009] The first formation average density in each track direction is calculated based on the first muon survival rate, and the second formation average density in each track direction is calculated based on the second muon survival rate;

[0010] The change in the average density of the formation is calculated based on the first formation average density and the second formation average density in the same track direction. If the change in the average density of the formation in all track directions is less than the preset threshold, it is determined that there is no disturbance in the formation; otherwise, it is determined that there is disturbance in the formation.

[0011] Furthermore, the muon survival rate is calculated based on the following formula:

[0012]

[0013] where R(φ,ψ) represents the muon survival rate in the track direction with zenith angle φ and azimuth angle ψ, and I D represents the underground muon flux in the track direction with zenith angle φ and azimuth angle ψ, I G represents the surface muon flux in the track direction with zenith angle φ and azimuth angle ψ.

[0014] Furthermore, the process of calculating the first formation average density in each track direction based on the first muon survival rate in the track direction includes the following:

[0015] The minimum energy value for a muon to penetrate the formation and generate a response in the detector is calculated based on the survival rate of the first muon in each track direction;

[0016] Based on the minimum energy value, the equivalent length of the formation that the muon passes through in the track direction is calculated;

[0017] The average density of the first formation in the track direction is calculated based on the equivalent length of the formation.

[0018] Furthermore, the equivalent length of the formation is calculated based on the following formula:

[0019] E min =a·L eff +b

[0020] Among them, E min represents the minimum energy value of a muon penetrating the formation and generating a response in the detector, a and b are constants, Leff It represents the equivalent length of the stratum that the muon passes through in the direction of this track.

[0021] Further, the average density of the first formation is calculated based on the following formula:

[0022] ρ ave =L eff / l

[0023] l=h / cosφ

[0024] Among them, ρ ave represents the average density of the first stratum, l represents the path length of the muon through the stratum, h represents the depth of the detector, and φ represents the zenith angle of the track direction.

[0025] Furthermore, the following contents are also included:

[0026] The historical data of the average density change of the formation in each track direction are counted, and the mean value and standard deviation of the historical data of the average density change of the formation in each track direction are calculated. The sum of the mean value and 3 times the standard deviation is used as the preset threshold value of the average density change of the formation in each track direction.

[0027] Furthermore, the muon flux in each track direction is calculated based on the following formula:

[0028]

[0029] Where S represents the effective detection area of ​​the detector, Δt represents the measurement time, and N(φ,ψ) represents the number of muons detected in the track direction with a zenith angle of φ and an azimuth angle of ψ.

[0030] In addition, the present invention also provides a system for detecting shield stratum disturbance based on cosmic ray muons, comprising:

[0031] The first data acquisition module is used to obtain the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the track direction of the muon and the muon flux in each track direction;

[0032] The second data acquisition module is used to obtain underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring point during the shield construction;

[0033] The muon survival rate calculation module is used to calculate the first muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, and calculate the second muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point;

[0034] A formation average density calculation module, used to calculate the first formation average density in each track direction based on the first muon survival rate in the track direction, and to calculate the second formation average density in the track direction based on the second muon survival rate in the track direction;

[0035] The formation disturbance analysis module is used to calculate the change in the formation average density based on the first formation average density and the second formation average density in the same track direction. If the change in the formation average density in all track directions is less than a preset threshold, it is determined that there is no disturbance in the formation, otherwise it is determined that there is disturbance in the formation.

[0036] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0037] In addition, the present invention also provides a computer-readable storage medium for storing a computer program for detecting shield stratum disturbance based on cosmic ray muons, wherein the computer program executes the steps of the method described above when running on a computer.

[0038] The present invention has the following beneficial effects:

[0039] The method for detecting shield stratum disturbance based on cosmic ray muons of the present invention uses cosmic ray muons as natural probes to measure muon information on the surface and underground of the shield construction area, thereby detecting the attenuation of muons after penetrating the stratum. Since muons will produce energy loss when passing through matter, the greater the density of the matter, the greater the energy lost by the muons per unit length passing through the matter, and the higher the flux attenuation, the average stratum density on each muon track can be calculated based on the muon flux attenuation information. In addition, by comparing the change in the average stratum density at the same monitoring point in the same track direction just after excavation and after a period of excavation, the stratum disturbance in the track direction is evaluated. If the change in the average stratum density in all track directions is less than the preset threshold, it means that there is no obvious change in the average stratum density at the monitoring point after the shield construction, and it can be determined that there is no stratum disturbance. Otherwise, it is determined that there is stratum disturbance. It can accurately and intuitively detect stratum disturbance, is not restricted by the surface environment, and has stronger applicability. It can also detect the disturbance of the stratum above the entire tunnel, with a larger detection range, realizing non-destructive detection and disturbance warning of the upper stratum during shield construction, providing important guarantees for construction safety.

[0040] In addition, the system for detecting shield stratum disturbance based on cosmic ray muons of the present invention also has the above advantages.

[0041] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0043] Figure 1 It is a flow chart of a method for detecting shield formation disturbance based on cosmic ray muons according to a preferred embodiment of the present application.

[0044] Figure 2 It is a schematic diagram of deploying a muon detector on a tunnel boring machine in a preferred embodiment of the present application.

[0045] Figure 3 yes Figure 1 Schematic diagram of the sub-process of step S4 in FIG.

[0046] Figure 4 It is another flow chart of the method for detecting shield formation disturbance based on cosmic ray muons according to the preferred embodiment of the present application.

[0047] Figure 5 It is a schematic diagram of the module structure of a system for detecting shield formation disturbance based on cosmic ray muons according to another embodiment of the present application.

[0048] Description of Reference Numerals

[0049] 1. Shield machine; 2. Muon detector; 3. Rear supporting trolley. DETAILED DESCRIPTION

[0050] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0051] Reference Figure 1 The preferred embodiment of the present application provides a method for detecting shield stratum disturbance based on cosmic ray muons, comprising the following contents:

[0052] Step S1: obtaining the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the muon track direction and the muon flux in each track direction;

[0053] Step S2: respectively obtaining underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring point during the shield construction;

[0054] Step S3: Based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, the first muon survival rate in each track direction is calculated; based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point, the second muon survival rate in each track direction is calculated;

[0055] Step S4: calculating the first formation average density in each track direction based on the first muon survival rate in the track direction, and calculating the second formation average density in the track direction based on the second muon survival rate in the track direction;

[0056] Step S5: Based on the first formation average density and the second formation average density in the same track direction, the formation average density change is calculated. If the formation average density change in all track directions is less than a preset threshold, it is determined that there is no disturbance in the formation; otherwise, it is determined that there is disturbance in the formation.

[0057] It can be understood that the method of detecting shield stratum disturbance based on cosmic ray muons in this embodiment first obtains the surface cosmic ray muon information of the shield construction area before shield construction, and then obtains the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point and when the supporting trolley moves to the preset monitoring point after the last section during the shield construction. Then, based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, the first muon survival rate in each track direction when the shield machine moves to the preset monitoring point is calculated. Similarly, the second muon survival rate in each track direction when the supporting trolley moves to the preset monitoring point after the last section can be calculated, and then the first formation average density and the second formation average density in each track direction are calculated according to the two muon survival rates. Finally, based on the first formation average density and the second formation average density in the same track direction, the change in the formation average density in the track direction is calculated. If the change in the formation average density in all track directions is less than the preset threshold, it is determined that there is no disturbance in the formation; otherwise, it is determined that there is disturbance in the formation.

[0058] Therefore, the method of detecting shield stratum disturbance based on cosmic ray muons of the present invention uses cosmic ray muons as natural probes to measure muon information on the surface and underground of the shield construction area, thereby detecting the attenuation of muons after penetrating the stratum. Since muons will produce energy loss when passing through matter, the greater the density of the matter, the greater the energy lost by the muons per unit length in the matter, and the higher the flux attenuation. Therefore, the average stratum density on each muon track can be calculated based on the muon flux attenuation information. In addition, by comparing the change in the average stratum density at the same monitoring point in the same track direction just after excavation and after a period of excavation, the stratum disturbance in the track direction is evaluated. If the change in the average stratum density in all track directions is less than the preset threshold, it means that there is no obvious change in the average stratum density at the monitoring point after the shield construction, and it can be determined that there is no stratum disturbance. Otherwise, it is determined that there is stratum disturbance. It can accurately and intuitively detect stratum disturbance, is not restricted by the surface environment, and has stronger applicability. It can also detect the disturbance of the stratum above the entire tunnel, with a larger detection range, realizing non-destructive detection and disturbance warning of the upper stratum during shield construction, providing important guarantees for construction safety.

[0059] It can be understood that in step S1, geological survey data in the shield construction area are collected, including geological survey information such as stratum thickness, geological structure, and lithology distribution, and a muon detector is set up at a flat location on the surface of the shield construction area for continuous measurement for a period of time, and the track direction of the surface cosmic ray muons and the muon flux in each direction during this period of time are recorded. Among them, assuming that the effective detection area of ​​the muon detector is S, the measurement time is Δt, and the number of muons detected in a certain track direction is N(φ,ψ), where φ represents the zenith angle and ψ represents the azimuth angle, the muon flux in each track direction can be calculated based on the following formula:

[0060]

[0061] It can be understood that in step S2, Figure 2As shown, a muon detector 2 is installed in the shield body of the shield machine 1 and on the supporting trolley 3 after the last section, respectively, to ensure that the detection surfaces of the two detectors are horizontally facing upward, and the measuring equipment is used to calibrate the relevant positions between each detector and the tunnel boring machine. During the shield construction, two muon detectors are started to measure the underground cosmic ray muon information after penetrating the overlying strata from the ground, including the muon track direction and the muon flux in each track direction. Therefore, according to the current tunnel boring machine coordinates and relative position calibration results during the shield construction process, the specific positions of the two detectors can be calculated, so that the measurement time, detection position, muon track direction (including muon track zenith angle and muon track azimuth) and muon flux can be recorded. It can be understood that during the shield construction process, when the shield machine moves to the preset monitoring point, it means that the preset monitoring point has just started to be excavated, and as the tunnel boring machine continues to excavate, when the supporting trolley after the last section moves to the preset monitoring point, it means that the preset monitoring point has been excavated for a period of time. In addition, the location and number of preset monitoring points can be set according to actual monitoring needs. For example, for the entire tunnel stratum, several monitoring points can be set at a certain distance to facilitate the detection of disturbances in the stratum above the entire tunnel. The detection range is larger and will not affect the shield construction progress.

[0062] It can be understood that since muons will generate energy loss when passing through matter, the greater the density of the matter, the greater the energy lost by the muons passing through a unit length in the matter, and the higher the flux attenuation, therefore, the average formation density of each muon track can be calculated based on the flux attenuation information measured by the detector. Therefore, in step S3, the surface muon flux and the underground muon flux are matched according to the direction of the muon track, and the surface muon flux and the underground muon flux corresponding to the same track direction are regarded as the detection of the same muon, and the muon flux attenuation information is characterized by calculating the survival rate of the same muon after penetrating the overlying formation, wherein the muon survival rate is specifically calculated based on the following formula:

[0063]

[0064] where R(φ,ψ) represents the muon survival rate in the track direction with zenith angle φ and azimuth angle ψ, and I D represents the underground muon flux in the track direction with zenith angle φ and azimuth angle ψ, I G represents the surface muon flux in the track direction with a zenith angle of φ and an azimuth of ψ. Therefore, based on the above formula, the first muon survival rate in each track direction when the shield machine moves to the preset monitoring point and the second muon survival rate in each track direction when the last rear supporting trolley moves to the preset monitoring point can be calculated respectively.

[0065] It can be understood that in step S4, the first formation average density in each track direction is calculated based on the first muon survival rate, and the second formation average density in each track direction is calculated based on the second muon survival rate. Figure 3 As shown, the process of calculating the first formation average density in each track direction based on the first muon survival rate in the track direction includes the following contents:

[0066] Step S41: Calculate the minimum energy value for a muon to penetrate the formation and generate a response in the detector based on the survival rate of the first muon in each track direction;

[0067] Step S42: Calculate the equivalent length of the formation that the muon passes through in the direction of the track based on the minimum energy value;

[0068] Step S43: Calculate the average density of the first formation in the direction of the track based on the formation equivalent length.

[0069] Specifically, the minimum energy value of the muon in each track direction that penetrates the formation and produces a response in the detector is calculated based on the following formula:

[0070]

[0071] Where E represents the muon energy, E cut represents the minimum energy value of the muon excitation detector response, Φ(φ,E) represents the muon differential flux model, which can adopt the Bogdananova model, Reyna-Bugaev model, etc.

[0072] Then, E min Equivalent length to the formation L eff There is a linear relationship between them, so the equivalent length of the formation can be calculated based on the following formula:

[0073] E min =a·L eff +b

[0074] Among them, E min represents the minimum energy value of a muon penetrating the stratum and generating a response in the detector. a and b are constants determined by the incident muon energy spectrum and the detector material. L eff It represents the equivalent length of the stratum that the muon passes through in the direction of this track.

[0075] The equivalent length L of the formation that the muon passes through in this track direction is eff is the integral of the formation density and the muon track length when the muon passes through the formation. Assuming that the formation density on a muon track is consistent, the average density of the first formation can be calculated based on the following formula:

[0076] ρave =L eff / l

[0077] l=h / cosφ

[0078] Among them, ρ ave represents the average density of the first formation, l represents the path length of the muon passing through the formation, h represents the depth of the detector, which is obtained by combining the detector coordinate information with the geological survey information, and φ represents the zenith angle of the track direction. In addition, the calculation process of the average density of the second formation is the same as that of the average density of the first formation, which will not be repeated here.

[0079] It can be understood that in step S5, the change amount of the average stratum density in the same track direction is calculated based on the first stratum average density and the second stratum average density in the same track direction, and the calculation formula is: Δρ=|ρ2-ρ1|, wherein ρ2 represents the second stratum average density calculated when the supporting trolley after the last section moves to the preset monitoring point, that is, the average stratum density of the preset monitoring point after a period of excavation, and ρ1 represents the first stratum average density calculated when the shield machine moves to the preset monitoring point, that is, the average stratum density of the preset monitoring point when it is just excavated. Then, the change amount of the average stratum density Δρ in the track direction is compared with the preset threshold value. If Δρ is less than the preset threshold value, it means that the average stratum density of the preset monitoring point in the track direction has not changed significantly during the shield construction, that is, there is no stratum disturbance in the track direction. If Δρ is not less than the preset threshold value, it means that the average stratum density of the preset monitoring point in the track direction has changed significantly during the shield construction, that is, there is stratum disturbance in the track direction. When Δρ in all track directions is less than the preset threshold, it is determined that there is no formation disturbance, otherwise it is determined that there is formation disturbance and a formation disturbance warning is triggered. The preset thresholds of the average formation density change in each track direction can be the same or different, and can be set manually as needed.

[0080] It can be understood that the present invention installs muon detectors at the head and tail positions of the tunnel boring machine respectively, and based on the flux attenuation characteristics of cosmic ray muons after penetrating the formation, the average density of the formation above the shield tunnel can be solved in real time. With continuous tunneling, the change of formation density at the same position and different time points can be obtained, so that the formation disturbance can be inferred by taking the formation density change value at the same position and different time as a reference value. The formation disturbance can be detected accurately and intuitively, and is not restricted by the surface environment, so it has stronger applicability. It can also detect the disturbance of the formation above the entire tunnel, and the detection range is larger, which realizes non-destructive detection and disturbance warning of the upper formation during shield construction, and provides important guarantee for construction safety.

[0081] Alternatively, if Figure 4As shown, the method for detecting shield stratum disturbance based on cosmic ray muons also includes the following contents:

[0082] Step S6: Count the historical data of the average density change of the formation in each track direction, calculate the average value and standard deviation of the historical data of the average density change of the formation in each track direction, and use the sum of the average value and 3 times the standard deviation as the preset threshold value of the average density change of the formation in each track direction.

[0083] It can be understood that by statistically analyzing the historical data of the average density change of the formation in each track direction, and taking the sum of the average value and 3 times the standard deviation as the preset threshold value of the average density change of the formation in each track direction, the accuracy of the formation disturbance warning can be further improved. In addition, in other embodiments of the present invention, all the historical data of the average density change of the formation can also be directly counted, and the statistics are no longer divided into track directions, so that the average value and standard deviation of all the historical data of the average density change of the formation can be calculated, and the sum of the average value and 3 times the standard deviation is used as the preset threshold value. At this time, the preset threshold values ​​corresponding to each track direction are the same.

[0084] In addition, if Figure 5 As shown, another embodiment of the present invention further provides a system for detecting shield formation disturbance based on cosmic ray muons, preferably using the method for detecting shield formation disturbance based on cosmic ray muons as described above, including:

[0085] The first data acquisition module is used to obtain the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the track direction of the muon and the muon flux in each track direction;

[0086] The second data acquisition module is used to obtain underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring point during the shield construction;

[0087] The muon survival rate calculation module is used to calculate the first muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, and calculate the second muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point;

[0088] A formation average density calculation module, used to calculate the first formation average density in each track direction based on the first muon survival rate in the track direction, and to calculate the second formation average density in the track direction based on the second muon survival rate in the track direction;

[0089] The formation disturbance analysis module is used to calculate the change in the formation average density based on the first formation average density and the second formation average density in the same track direction. If the change in the formation average density in all track directions is less than a preset threshold, it is determined that there is no disturbance in the formation, otherwise it is determined that there is disturbance in the formation.

[0090] It can be understood that the system of the present embodiment for detecting shield stratum disturbance based on cosmic ray muons first obtains the surface cosmic ray muon information of the shield construction area before shield construction, and then obtains the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point and when the supporting trolley moves to the preset monitoring point after the last section during the shield construction. Then, based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, the first muon survival rate in each track direction when the shield machine moves to the preset monitoring point is calculated. Similarly, the second muon survival rate in each track direction when the supporting trolley moves to the preset monitoring point after the last section can be calculated, and then the first formation average density and the second formation average density in each track direction are calculated according to the two muon survival rates. Finally, based on the first formation average density and the second formation average density in the same track direction, the change in the formation average density in the track direction is calculated. If the change in the formation average density in all track directions is less than the preset threshold, it is determined that there is no disturbance in the formation; otherwise, it is determined that there is disturbance in the formation.

[0091] Therefore, the system for detecting shield stratum disturbance based on cosmic ray muons of the present invention uses cosmic ray muons as natural probes to measure muon information on the surface and underground of the shield construction area, so as to detect the attenuation of muons after penetrating the stratum. Since muons will produce energy loss when passing through matter, the greater the density of the matter, the greater the energy lost by the muons per unit length in the matter, and the higher the flux attenuation. Therefore, the average stratum density on each muon track can be calculated based on the muon flux attenuation information. In addition, by comparing the change in the average stratum density at the same monitoring point in the same track direction just after excavation and after a period of excavation, the stratum disturbance in the track direction is evaluated. If the change in the average stratum density in all track directions is less than the preset threshold, it means that there is no obvious change in the average stratum density at the monitoring point after the shield construction, and it can be determined that there is no stratum disturbance. Otherwise, it is determined that there is stratum disturbance. It can accurately and intuitively detect stratum disturbance, is not restricted by the surface environment, and has stronger applicability. It can also detect the disturbance of the stratum above the entire tunnel, with a larger detection range, realizing non-destructive detection and disturbance warning of the upper stratum during shield construction, providing important guarantees for construction safety.

[0092] In addition, the system for detecting shield stratum disturbance based on cosmic ray muons also includes:

[0093] The statistical analysis module is used to count the historical data of the average density change of the formation in each track direction, calculate the mean value and standard deviation of the historical data of the average density change of the formation in each track direction, and use the sum of the mean value and 3 times the standard deviation as the preset threshold value of the average density change of the formation in each track direction.

[0094] In addition, another embodiment of the present invention further provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0095] In addition, another embodiment of the present invention further provides a computer-readable storage medium for storing a computer program for detecting shield formation disturbance based on cosmic ray muons, wherein the computer program executes the steps of the method described above when running on a computer.

[0096] The general form of computer readable storage media includes: floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with a pattern of holes, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash erasable programmable read-only memory (FLASH-EPROM), any other memory chip or cartridge, or any other medium that can be read by a computer. The instructions can further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium that can be used to store, encode or carry instructions for execution by a machine, and includes digital or analog communication signals or other intangible media that facilitate the communication of the above instructions. Transmission media include coaxial cables, copper wires and optical fibers, which include the wires of a bus used to transmit a computer data signal.

[0097] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0098] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0099] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0100] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0101] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0102] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting shield stratum disturbance based on cosmic ray muons, characterized in that: Includes the following: Obtaining the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the muon track direction and the muon flux in each track direction; The underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring points during the shield construction are obtained respectively; Based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, the first muon survival rate in each track direction is calculated; based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point, the second muon survival rate in each track direction is calculated; The first formation average density in each track direction is calculated based on the first muon survival rate, and the second formation average density in each track direction is calculated based on the second muon survival rate; The change in the average density of the formation is calculated based on the first formation average density and the second formation average density in the same track direction. If the change in the average density of the formation in all track directions is less than the preset threshold, it is determined that there is no disturbance in the formation; otherwise, it is determined that there is disturbance in the formation.

2. The method for detecting shield stratum disturbance based on cosmic ray muons according to claim 1, characterized in that: The muon survival rate was calculated based on the following formula: where R(φ,ψ) represents the muon survival rate in the track direction with zenith angle φ and azimuth angle ψ, and I D represents the underground muon flux in the track direction with zenith angle φ and azimuth angle ψ, I G represents the surface muon flux in the track direction with zenith angle φ and azimuth angle ψ.

3. The method for detecting shield stratum disturbance based on cosmic ray muons according to claim 1, characterized in that: The process of calculating the average density of the first formation in each track direction based on the first muon survival rate in the track direction includes the following: The minimum energy value for a muon to penetrate the formation and generate a response in the detector is calculated based on the survival rate of the first muon in each track direction; Based on the minimum energy value, the equivalent length of the formation that the muon passes through in the track direction is calculated; The average density of the first formation in the track direction is calculated based on the equivalent length of the formation.

4. The method for detecting shield stratum disturbance based on cosmic ray muons as claimed in claim 3, characterized in that: The equivalent length of the formation is calculated based on the following formula: E min =a·L eff +b Among them, E min represents the minimum energy value of a muon penetrating the formation and generating a response in the detector, a and b are constants, L eff It represents the equivalent length of the stratum that the muon passes through in the direction of this track.

5. The method for detecting shield stratum disturbance based on cosmic ray muons as claimed in claim 4, characterized in that: The average density of the first formation is calculated based on the following formula: r ave =L eff / l l=h / cosφ Among them, ρ ave represents the average density of the first stratum, l represents the path length of the muon passing through the stratum, h represents the depth of the detector, and φ represents the zenith angle of the track direction.

6. The method for detecting shield stratum disturbance based on cosmic ray muons according to claim 1, characterized in that: Also included are the following: The historical data of the average density change of the formation in each track direction are counted, and the mean value and standard deviation of the historical data of the average density change of the formation in each track direction are calculated. The sum of the mean value and 3 times the standard deviation is used as the preset threshold value of the average density change of the formation in each track direction.

7. The method for detecting shield stratum disturbance based on cosmic ray muons according to claim 1, characterized in that: The muon flux in each track direction is calculated based on the following formula: Where S represents the effective detection area of ​​the detector, Δt represents the measurement time, and N(φ,ψ) represents the number of muons detected in the track direction with a zenith angle of φ and an azimuth angle of ψ.

8. A system for detecting shield stratum disturbance based on cosmic ray muons, characterized in that: include: The first data acquisition module is used to obtain the surface cosmic ray muon information in the shield construction area, wherein the cosmic ray muon information includes the track direction of the muon and the muon flux in each track direction; The second data acquisition module is used to obtain underground cosmic ray muon information measured when the shield machine and the supporting trolley after the last section move to the preset monitoring point during the shield construction; The muon survival rate calculation module is used to calculate the first muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the shield machine moves to the preset monitoring point, and calculate the second muon survival rate in each track direction based on the surface cosmic ray muon information and the underground cosmic ray muon information measured when the last rear supporting trolley moves to the preset monitoring point; A formation average density calculation module, used to calculate the first formation average density in each track direction based on the first muon survival rate in the track direction, and to calculate the second formation average density in the track direction based on the second muon survival rate in the track direction; The formation disturbance analysis module is used to calculate the change in the formation average density based on the first formation average density and the second formation average density in the same track direction. If the change in the formation average density in all track directions is less than a preset threshold, it is determined that there is no disturbance in the formation, otherwise it is determined that there is disturbance in the formation.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method according to any one of claims 1 to 7 by calling the computer program stored in the memory.

10. A computer-readable storage medium for storing a computer program for detecting shield stratum disturbance based on cosmic ray muons, characterized in that: When the computer program is run on a computer, the steps of the method according to any one of claims 1 to 7 are executed.

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