A shield tunnel composite stratum soft and hard interface distribution sensing method and system

Abstract

The disclosure provides a shield tunnel composite stratum soft and hard interface distribution sensing method and system, relates to the technical field of shield and TBM engineering, and comprises the following steps: acquiring vibration signals generated by cutter head rotation through a plurality of sensors arranged; extracting key time difference information in the preprocessed vibration signals; constructing a three-dimensional space coordinate system according to the arrangement space coordinate information of the plurality of sensors, setting a space region where a vibration source is to be positioned, assuming that the transmission process of the vibration signals from the vibration source to the sensors satisfies uniform velocity propagation, based on the key time difference information, and through a multi-sensor vibration target positioning algorithm based on three-point positioning, a stratum soft and hard interface positioning line forming a tunneling section is described, so as to position the stratum soft and hard three-dimensional interface and obtain the distribution form of the stratum soft and hard interface; and the disclosure realizes uninterrupted imaging of the stratum soft and hard interface and effectively avoids the two-dimensional discontinuity of the geological profile obtained in the drilling method.

Description

Technical Field

[0001] This disclosure relates to the field of shield tunneling and TBM engineering technology, specifically to a method and system for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] In recent years, with the rapid development of urban infrastructure, underground space development has increased significantly. The shield tunneling method, with its advantages of minimal disturbance to the surrounding environment and no disruption to surface traffic during construction, has been widely used in tunnel construction. During shield tunneling, the basic geological conditions and engineering geological conditions have a significant impact on construction efficiency and cutterhead wear. The geological strata can generally be divided into homogeneous strata and composite strata. Homogeneous strata refer to strata composed of a single soft soil layer; however, strictly homogeneous strata do not exist in reality. In contrast, composite strata generally refer to a combination of different strata above and below the tunnel section.

[0004] Due to the significant differences in the mechanical properties of soil and rock in composite strata, tunneling parameters are difficult to control, which can easily lead to poor tunneling posture during shield tunneling. In severe cases, it can also cause local damage to tunnel segments and surface collapse, seriously affecting construction progress and safety.

[0005] However, existing geological interface detection mainly relies on drilling. Due to the limitations of drilling itself, the geological information obtained is obviously discontinuous. The geological profile is a two-dimensional interface along the tunneling direction, which cannot accurately obtain the distribution of soft interfaces in the strata at the excavation face. Summary of the Invention

[0006] To address the aforementioned issues, this disclosure proposes a method and system for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels. By establishing a method for locating the soft and hard interfaces in composite strata of shield tunnels, the two-dimensional discontinuity in geological profile acquisition during drilling is avoided, thereby achieving accurate sensing of the distribution of soft and hard interfaces in the strata.

[0007] According to some embodiments, the present disclosure adopts the following technical solutions:

[0008] A method for sensing the distribution of the soft-hard interface in composite strata of a shield tunnel includes:

[0009] Vibration signals generated by the rotation of the cutter head are acquired by deploying multiple sensors, and the vibration signals are preprocessed.

[0010] Extract key time difference information from the preprocessed vibration signal;

[0011] Based on the spatial coordinate information of the multi-sensor deployment, a three-dimensional spatial coordinate system is constructed, and the spatial area for the vibration source to be located is set. It is assumed that the transmission process of the vibration signal from the vibration source to the sensor satisfies uniform propagation. Based on the key time difference information, the positioning line of the soft and hard interface of the stratum forming the tunnel section is characterized by a multi-sensor vibration target positioning algorithm based on three-point positioning, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution pattern of the soft and hard interface of the stratum.

[0012] According to some embodiments, the present disclosure adopts the following technical solutions:

[0013] A sensing system for the distribution of soft and hard interfaces in composite strata of shield tunnels includes:

[0014] The data acquisition module is used to acquire vibration signals generated by the rotation of the cutter head through multiple deployed sensors and to preprocess the vibration signals.

[0015] The data extraction module is used to extract key time difference information from the preprocessed vibration signal;

[0016] The positioning module is used to construct a three-dimensional spatial coordinate system based on the spatial coordinate information of the multi-sensor deployment, set the spatial area where the vibration source is to be located, assume that the transmission process of the vibration signal from the vibration source to the sensor meets the uniform propagation, and based on key time difference information, use a multi-sensor vibration target positioning algorithm based on three-point positioning to characterize the positioning line of the soft and hard interface of the stratum forming the tunnel section, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution morphology of the soft and hard interface of the stratum.

[0017] According to some embodiments, the present disclosure adopts the following technical solutions:

[0018] A non-transitory computer-readable storage medium is provided for storing computer instructions, which, when executed by a processor, implement the aforementioned method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels.

[0019] According to some embodiments, the present disclosure adopts the following technical solutions:

[0020] An electronic device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to implement the method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels.

[0021] Compared with the prior art, the beneficial effects of this disclosure are as follows:

[0022] This disclosure discloses a method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels. It adopts passive source positioning and identification based on cutter vibration information, without the need for additional active sources. Through the full-space deployment of sensors in a three-ring, six-diameter configuration and multi-point array reception, it can achieve full coverage acquisition of vibration information of the cutting system with reliable signal. By deploying sensors at the front shield diaphragm to implement a multi-point continuous monitoring mode, it can achieve uninterrupted imaging of the soft and hard interfaces of the strata, effectively avoiding the two-dimensional discontinuity in geological profile acquisition in drilling methods.

[0023] This disclosure presents a method for sensing the distribution of the soft-hard interface in composite strata of shield tunnels. It achieves multi-source localization fitting of key vibration points and realizes uninterrupted imaging of the soft-hard interface through continuous multi-point monitoring of sensors, effectively avoiding the two-dimensional discontinuity in geological profile acquisition used in drilling methods. Furthermore, based on existing massive amounts of stratum interface localization information and leveraging big data analysis algorithms, it infers the general distribution of the soft-hard interface in the composite strata ahead of the excavation face, providing a reference for optimizing shield tunneling parameters. Attached Figure Description

[0024] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0025] Figure 1 This is a schematic diagram of a multi-sensor three-ring six-path deployment method according to an embodiment of this disclosure;

[0026] Figure 2 This is a schematic diagram of the vibration source spatial positioning algorithm according to an embodiment of the present disclosure. Detailed Implementation

[0027] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0028] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] Example 1

[0031] One embodiment of this disclosure provides a method for sensing the distribution of the soft and hard interface in a composite stratum of a shield tunnel, including the following steps:

[0032] Step 1: Acquire vibration signals generated by the rotation of the cutter head through multiple deployed sensors, and preprocess the vibration signals;

[0033] Step 2: Extract key time difference information from the preprocessed vibration signal;

[0034] Step 3: Based on the spatial coordinate information of the multi-sensor deployment, construct a three-dimensional spatial coordinate system, set the spatial area for the vibration source to be located, assume that the transmission process of the vibration signal from the vibration source to the sensor satisfies uniform propagation, and based on key time difference information, use a multi-sensor vibration target positioning algorithm based on three-point positioning to characterize the positioning line of the soft and hard interface of the strata forming the tunnel section, thereby locating the three-dimensional interface of the soft and hard strata and obtaining the distribution morphology of the soft and hard interface of the strata.

[0035] As one embodiment, the shield tunnel composite stratum soft-hard interface distribution sensing method disclosed herein is based on the principle of improving the shield tunnel composite stratum soft-hard interface positioning method according to the difference in vibration signal characteristics generated by the shield cutter cutting the rock and soil layers, thereby obtaining the distribution morphology of the tunnel composite stratum soft-hard interface. The shield tunnel composite stratum soft-hard interface positioning method disclosed herein consists of three parts: first, signal receiving mode; second, sensor deployment scheme; and third, soft-hard interface spatial positioning algorithm.

[0036] Furthermore, the vibration signal receiving mode in the shield tunnel composite stratum soft-hard interface positioning method disclosed herein is to preliminarily determine the feasibility of using vibration signal as a soft-hard interface criterion through the vibration response of the "roller cutter-cutterhead-front shield diaphragm" cutting system; this feasibility has been verified by modal experiments, that is, before the shield machine is lowered into the shaft, a vibrator is used to apply simulated vibration at the cutter position, and the vibration information of the front shield diaphragm is monitored by vibration sensors, and it is found that the signal amplitude and frequency characteristics are consistent with the characteristics of the excitation signal of the vibrator.

[0037] Revealing the propagation law of vibration signals in the cutting system, such as Figure 1 As shown, the central metal component is the drive bearing of the tunnel boring machine, surrounded by steel plates of a certain thickness. The study verifies the effectiveness of vibration signal transmission from the cutterhead to the cutter disc and then to the front shield diaphragm, clarifies the significant differences in vibration response of the cutterhead when encountering uneven strata, and, based on the on-site spatial selection of the tunnel boring machine cutting system, establishes a multi-point array signal receiving mode at the front shield diaphragm location, i.e., deploying sensors at multiple points in a two-dimensional spatial array.

[0038] Furthermore, regarding the deployment of multiple sensors, this disclosure proposes a full-coverage three-ring, six-diameter sensor deployment scheme based on the spatial coordinate information of the front shield diaphragm to achieve full-space monitoring of vibration information of the cutting system. Specifically, the sensors are deployed at three different circumferential distances, with the center of the front shield diaphragm as the center. Based on the radius of the circular front shield diaphragm, the radius is divided into four parts from the center to the edge. The specific distance depends on whether there are obstructions on the diaphragm (the structure of the tunnel boring machine itself). Three different radii are flexibly selected to form three rings, i.e., three circumferential directions. Figure 1 The three dashed lines shown represent the circumferential direction.

[0039] Furthermore, six different radial distances were selected in three circumferential directions to accommodate the deployment of sensors throughout the entire space. The front shield bulkhead is located at the very front of the tunnel boring machine, accessible to personnel. Further forward is the soil chamber, and in front of the soil chamber is the cutterhead. The front shield bulkhead acts as a protective wall. Figure 1 As shown, looking counterclockwise from the left, A4 is located in the first radial direction, A2 and A3 in the second radial direction, A1 in the third radial direction, B1 in the fourth radial direction, and so on, with B4 in the sixth radial direction. The angle of each radial direction also depends on whether there are obstacles on the front shield bulkhead and can be determined based on the actual situation on site.

[0040] like Figure 1 As shown, the gray area is the front shield bulkhead, which can be understood as a steel plate. The middle metal mechanical structure is the tunnel boring machine's drive bearing, used to drive the front cutterhead to rotate. The muck outlet is where the soil cut by the cutters is transported out. The black circles represent the sensor placement positions; A1 to A4 indicate the four sensors placed on the left side of the disc, and B1 to B4 indicate the installation positions of the four sensors on the right side.

[0041] As one example, the multi-sensor uses a frequency conversion vibration measurement device with four adjustable speed settings to meet the signal requirements of different frequencies. The high-resolution acquisition can adapt to the environment of shield tunnel construction.

[0042] Furthermore, after the deployment of multiple sensors is completed, the sensors collect vibration signals generated by the rotation of the cutterhead, perform wavelet analysis filtering on the vibration signals, extract key time information, and achieve target localization through a multi-sensor vibration target localization algorithm based on three-point positioning. Specifically:

[0043] Based on the spatial coordinate information of the multi-sensor deployment, a three-dimensional rectangular coordinate system is constructed with the center of the front shield as the origin. Based on the key time difference information in the vibration signal received by the sensor, a multi-sensor vibration target positioning algorithm based on three-point positioning is established. Before the algorithm is calculated, the spatial coordinate information of all sensors needs to be set in advance, and the spatial area to be located of the vibration source needs to be set. It is assumed that the signal propagates at a constant speed during the transmission process from the vibration source to the sensor. The resulting coordinate algorithm is as shown in formula (1).

[0044]

[0045] In the formula, x and y are the spatial coordinates of the vibration source, x i and y i Let Δt be the spatial coordinates of the sensor. ij denoted as time difference, and v as the transmission speed from the vibration source to the sensor.

[0046] The multi-sensor vibration target localization algorithm based on three-point positioning consists of three sets of hyperbolic equations. The spatial location of the vibration source is determined by the intersection of these three hyperbolas in space. Figure 2 This describes the relationship between wave propagation time difference and geometric location. Based on the time difference of signals received by different sensors, the distance difference is calculated. In two-dimensional space, the time difference between two sensors forms a hyperbola because the locus of points whose distance difference to two fixed points is constant is a hyperbola. Therefore, with only two sensors, the possible vibration location lies on this hyperbola. However, in practical applications, at least three sensors are needed to determine the intersection point, that is, the specific location of the vibration. Figure 2 N1, N2, and N3 are the positions of three sensors. The time difference between sensors N1 and N2 forms hyperbola 1. Similarly, N1 and N3 form hyperbola 2, and N3 and N2 form hyperbola 3. The location of the vibration (i.e., the vibration source S) can be determined based on the intersection of each set of hyperbolas.

[0047] Furthermore, the spatial location information of multiple vibration sources can be obtained simultaneously by collecting vibration signals. By characterizing multiple points, the positioning line of the soft and hard interface of the stratum of the tunnel section can be formed. Using a large amount of data, a large number of points can be located. Multiple points are used to form lines, and finally a surface is formed. However, this process is generated multiple times. Specifically, when the tunnel boring machine advances to a certain position, a line (soft and hard interface boundary line) will be located on the excavation surface. The tunnel boring machine continues to advance forward. When it reaches each surface, there will be a boundary line. Then, N boundary lines will form a three-dimensional surface. As the tunnel boring machine advances, the boundary lines on each excavation face form a three-dimensional surface, which can continuously delineate the positioning lines of the soft and hard interfaces of the strata at each excavation section. During data processing and imaging, low-pass filtering is used to remove high-frequency noise (such as mechanical vibration noise) and power frequency interference. Peak factor, root mean square value, kurtosis in the time domain and dominant frequency component and frequency band energy ratio in the frequency domain are extracted. Combined with wavelet transform, the abrupt change points of vibration signals in time and frequency are located, and the instantaneous impact events corresponding to the stratum boundary are identified. The soft and hard three-dimensional interfaces of the strata can be located continuously and accurately, thereby obtaining the current distribution pattern of the soft and hard three-dimensional interfaces of the strata.

[0048] Example 2

[0049] One embodiment of this disclosure provides a sensing system for the distribution of soft and hard interfaces in composite strata of a shield tunnel, including a data acquisition module, a data extraction module, and a positioning module, wherein:

[0050] The data acquisition module is used to acquire vibration signals generated by the rotation of the cutter head through multiple deployed sensors and to preprocess the vibration signals.

[0051] The data extraction module is used to extract key time difference information from the preprocessed vibration signal;

[0052] The positioning module is used to construct a three-dimensional spatial coordinate system based on the spatial coordinate information of the multi-sensor deployment, set the spatial area where the vibration source is to be located, assume that the transmission process of the vibration signal from the vibration source to the sensor meets the uniform propagation, and based on key time difference information, use a multi-sensor vibration target positioning algorithm based on three-point positioning to characterize the positioning line of the soft and hard interface of the stratum forming the tunnel section, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution morphology of the soft and hard interface of the stratum.

[0053] As one embodiment, the data acquisition module includes the deployment of vibration sensors, the deployment and connection of data acquisition devices, and the implementation of vibration data acquisition methods, specifically:

[0054] First, sensors are installed at predetermined spatial positions on the back side of the front shield bulkhead. Adhesive is used as a coupling medium between the sensors and the bulkhead to enhance the effectiveness of vibration signal transmission.

[0055] Secondly, a data acquisition device is installed in the middle shield section. The data acquisition device is powered by AC power and is wired to the front vibration sensor to receive the vibration information transmitted by the sensor in real time.

[0056] During normal tunneling, the vibration signals generated by the cutterhead rotation are collected in real time by vibration sensors, and the raw data is stored in the acquisition instrument.

[0057] Furthermore, the data extraction module includes a data processing terminal. The raw vibration signals collected by the sensors are transmitted to the data processing terminal, where wavelet analysis and filtering are performed on the information to extract key features. This provides a foundation for the next step of depicting the positioning lines of the soft and hard interfaces of the strata at each tunneling section, and further realizing the three-dimensional visualization of the soft and hard interfaces of the strata along the excavation axis.

[0058] Furthermore, in the positioning module, a three-dimensional spatial coordinate system is constructed based on the spatial coordinate information of the multi-sensor deployment, and the spatial area to be located for the vibration source is set. It is assumed that the transmission process of the vibration signal from the vibration source to the sensor satisfies uniform propagation. Based on key time difference information, the positioning line of the soft and hard interface of the stratum forming the tunnel section is characterized by a multi-sensor vibration target positioning algorithm based on three-point positioning, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution morphology of the soft and hard interface of the stratum.

[0059] Example 3

[0060] One embodiment of this disclosure provides a non-transitory computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, they implement the method for sensing the distribution of soft and hard interfaces in composite strata of a shield tunnel.

[0061] Example 4

[0062] One embodiment of this disclosure provides an electronic device, including a processor, a memory, and a computer program; wherein the processor is connected to the memory, and the computer program is stored in the memory. When the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to implement the method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels.

[0063] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0064] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0065] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels, characterized in that, include: Vibration signals generated by the rotation of the cutter head are acquired by deploying multiple sensors, and the vibration signals are preprocessed. Extract key time difference information from the preprocessed vibration signal; Based on the spatial coordinate information of the multi-sensor deployment, a three-dimensional spatial coordinate system is constructed, and the spatial area where the vibration source is to be located is set. It is assumed that the transmission process of the vibration signal from the vibration source to the sensor satisfies uniform propagation. Based on the key time difference information, the positioning line of the soft and hard interface of the stratum forming the tunnel section is characterized by a multi-sensor vibration target positioning algorithm based on three-point positioning, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution pattern of the soft and hard interface of the stratum. The multi-sensor deployment method is as follows: the multi-sensor deployment method is multi-point deployment, and it is set to a two-dimensional spatial array arrangement, so that the signal reception is a multi-point array signal reception mode; the cutting head of the shield is monitored in the whole space. Based on the spatial coordinate information of the front shield bulkhead, a three-ring six-path multi-sensor deployment method is adopted. With the center of the front shield bulkhead as the center, the sensors are deployed on the front shield bulkhead at three different circumferential distances. Six different radial distances are selected in the three circumferential directions to realize the three-ring six-path deployment of multi-sensors in the whole space.

2. The method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in claim 1, characterized in that, By constructing a three-dimensional spatial coordinate system, based on the time difference information of the vibration signals received by the sensors, and using a multi-sensor vibration target localization algorithm based on three-point positioning, the spatial coordinate information of all sensors is pre-set, and the spatial region where the vibration source is to be located is defined. Assuming that the signal propagates at a uniform speed during its transmission from the vibration source to the sensor, the resulting coordinate formula is: in, x and y The spatial coordinates of the vibration source x i and y i Let Δ be the spatial coordinates of the sensor. t ij Time difference; v The velocity transmitted from the vibration source to the sensor.

3. The method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in claim 1, characterized in that, The multi-sensor vibration target localization algorithm based on three-point positioning consists of multiple sets of hyperbolic equations. The spatial location of the vibration source is determined by the intersection of these hyperbolas in space.

4. The method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in claim 1, characterized in that, The spatial location information of multiple vibration sources is obtained at the same time by acquiring vibration signals, and the positioning line of the soft and hard interface of the strata of the tunnel section is formed by multi-point characterization.

5. The method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in claim 1, characterized in that, The vibration signal adopts a continuous monitoring mode to continuously delineate the positioning line of the soft and hard interface of the stratum at each tunneling section. Through data processing and imaging, the three-dimensional interface of the soft and hard stratum is continuously located. Based on the obtained distribution information of the soft and hard interface of the stratum, the distribution morphology of the soft and hard interface in the unexcavated part is inferred.

6. A sensing system for the distribution of soft and hard interfaces in composite strata of shield tunnels, characterized in that, The method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in any one of claims 1-5 includes: The data acquisition module is used to acquire vibration signals generated by the rotation of the cutter head through multiple deployed sensors and to preprocess the vibration signals. The data extraction module is used to extract key time difference information from the preprocessed vibration signal; The positioning module is used to construct a three-dimensional spatial coordinate system based on the spatial coordinate information of the multi-sensor deployment, set the spatial area where the vibration source is to be located, assume that the transmission process of the vibration signal from the vibration source to the sensor meets the uniform propagation, and based on key time difference information, use a multi-sensor vibration target positioning algorithm based on three-point positioning to characterize the positioning line of the soft and hard interface of the stratum forming the tunnel section, thereby locating the three-dimensional interface of the soft and hard stratum and obtaining the distribution morphology of the soft and hard interface of the stratum.

7. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium is used to store computer instructions, which, when executed by a processor, implement the method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in any one of claims 1-5.

8. An electronic device, characterized in that, include: The device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, and the computer program is stored in the memory. When the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to implement the method for sensing the distribution of soft and hard interfaces in composite strata of shield tunnels as described in any one of claims 1-5.

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