Calculation method for minimum safe detection distance of tunnel geological prediction advanced detection

Abstract

This invention relates to a method for calculating the minimum safe detection distance for advanced detection in tunnel geological prediction, including a method based on the saturated uniaxial compressive strength R of rock. c The method calculates the estimated thickness of the engineering disturbance (h1); the estimated load height (h2) based on the tunnel surrounding rock conditions; and the estimated safety protection thickness (h3) based on the tunnel rock and water content. Based on the estimated thicknesses h1, h2, and h3, the minimum safe detection distance for advanced geological prediction of the tunnel is determined as H = w1·h1 + w2·h2 + w3·h3. This invention's calculation method quantifies the potential safety impact range based on different factors such as construction disturbance, surrounding rock load, and water-bearing structures. It constructs a method for estimating the minimum safe detection distance for advanced geological prediction of sudden surge disasters in mountainous highway tunnels using transient electromagnetic methods, based on the cumulative impact range. This provides a basis for the management and control of sudden surge disasters in mountainous highway tunnels.

Description

Technical Field

[0001] This invention belongs to the technical field of geological exploration, and specifically relates to a method for calculating the minimum safe detection distance for advanced detection in tunnel geological prediction. Background Technology

[0002] In mountainous highway tunnel construction, advanced geological exploration is a crucial step in preventing tunnel gas surges. Most gas surges occur primarily due to technological limitations and insufficient detection range coverage. Current mainstream advanced geological forecasting relies mainly on the effective detection range of equipment for sequential detection work, often using experience to determine the minimum safe detection distance, which creates certain safety hazards related to gas surges. Therefore, there is an urgent need to develop a quantifiable method for estimating the minimum safe detection distance for tunnel advanced geological exploration, providing support for tunnel geological hazard risk prevention and control.

[0003] Judging from the occurrence of tunnel bursts, the current method of combining short-range ground-penetrating radar detection and long-range tunneling pump (TSP) detection is basically effective in controlling bursts caused by water-bearing structures in front of the tunnel face, but the control effect on the upper and side is relatively poor. At the same time, the mismatch between radar short-range detection and effective safety protection thickness is the root cause of most of the disasters.

[0004] Currently, the estimation methods for the minimum safe detection distance are usually based on a comprehensive consideration of factors such as geological conditions, detection technology, and construction requirements. Common estimation methods include: Empirical Formula Method: Based on historical data and engineering experience, empirical formulas applicable to specific geological conditions and detection technologies are summarized. This method is simple and easy to implement, but is greatly limited by regional and technical limitations. Numerical Simulation Method: Using computer simulation technology to numerically simulate geological changes during tunnel construction, thereby deriving the minimum safe detection distance. This method can consider many complex factors, but the computational load is large and the model accuracy requirements are high. Risk Assessment Method: Combining geological conditions, construction difficulty, safety risks, and other factors to conduct risk assessments, and determining the minimum safe detection distance based on the assessment results. This method can comprehensively consider multiple factors, but the assessment process is complex and requires extensive professional knowledge and experience. Therefore, there is an urgent need for a more effective method to determine the minimum safe detection distance for tunnel geological prediction and advance detection. Summary of the Invention

[0005] The proposed method for calculating the minimum safe detection distance for tunnel geological forecasting and advance detection is based on a quantitative estimation method for the potential safety impact range of different factors such as construction disturbance, surrounding rock load, and water-bearing structure. It constructs an estimation method and index system for the minimum safe detection distance for advance geological forecasting of sudden surge disasters in mountainous highway tunnels using transient electromagnetic method based on the cumulative impact range, providing a basis for the management and control of sudden surge disasters in mountainous highway tunnels.

[0006] The first aspect of this invention provides a method for calculating the minimum safe detection distance for advanced detection in tunnel geological prediction, comprising the following steps:

[0007] Based on the saturated uniaxial compressive strength R of rock c The estimated thickness of the engineering disturbance, h1, is obtained by calculation;

[0008] Based on the surrounding rock conditions of the tunnel, the estimated load height h2 is calculated;

[0009] Based on the tunnel rock and water content conditions, the estimated safety protection thickness h3 is calculated;

[0010] Based on the estimated thickness of engineering disturbance h1, the estimated height of load h2, and the estimated thickness of safety protection h3, the minimum safe detection distance for tunnel geological prediction advance detection is determined as H = w1·h1 + w2·h2 + w3·h3, where w1, w2, and w3 are weighting coefficients.

[0011] As a further limitation of the present invention, the rock saturated uniaxial compressive strength R c The calculated engineering disturbance thickness estimate, taking into account lithological hardness, includes:

[0012] Based on the saturated uniaxial compressive strength R of the rock c Corresponding to the qualitative classification of rock hardness, different boundary strength values ​​are defined for the rock. A curve showing the relationship between uniaxial compressive strength and engineering disturbance thickness is plotted. Based on this curve, the estimated engineering disturbance thickness h1 is obtained by fitting.

[0013] As a further limitation of the present invention, the specific method for obtaining the engineering disturbance thickness estimate by fitting the curve of the relationship between uniaxial compressive strength and engineering disturbance thickness is as follows: using the saturated uniaxial compressive strength, the rock is divided into 5 levels from hard to soft: hard, relatively hard, relatively soft, soft, and extremely soft, with limit strength values ​​of 60MPa, 30MPa, 15MPa, and 5MPa, respectively. The engineering disturbance thickness estimate formula can be obtained by fitting the upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range.

[0014] As a further limitation of the present invention, the formula for estimating the thickness of the engineering disturbance is: In the formula, h1 is the engineering disturbance thickness, in meters; R c The value represents the saturated uniaxial compressive strength of the rock, expressed in MPa; 33.82 is expressed in MPa·m.

[0015] As a further limitation of the present invention, the saturated uniaxial compressive strength of the surrounding rock at the tunnel face is substituted into R in the h1 formula. c The estimated thickness of the engineering disturbance can then be obtained.

[0016] As a further limitation of the present invention, the estimated load height calculated based on the tunnel surrounding rock conditions includes:

[0017] Based on the conditions for the generation of surrounding rock pressure, the estimated load height h2 is calculated to be 0.45 × 2. s-1 ×[1+i(B-5)], where s is the surrounding rock grade, taking integers from 1 to 5; B is the tunnel width, in meters; i is the rate of increase or decrease in surrounding rock pressure for every 1 meter increase or decrease in tunnel width. If B < 5, then i = 0.2; if 5 ≤ B < 14, then i = 0.1; if 14 ≤ B < 25, then i = 0.07 for pilot tunnel excavation, and i = 0.12 for step-up or single-stage excavation.

[0018] As a further limitation of the present invention, the estimated thickness of the security protection layer...

[0019] In the formula, γ is the specific gravity of water, in kN / m³. 3 h represents the static water pressure inside the aquifer, in kPa; S1 represents the vertical projection of the bottom of the aquifer, in meters. 2 c represents the cohesion of the protective layer, in kPa; C1 represents the perimeter of the protective layer projected along the bottom of the water-bearing structure, in meters.

[0020] As a further limitation of the present invention, under conservative conditions, without considering the protective capacity of the surrounding rock within the engineering disturbance thickness range, the protective capacity of the surrounding rock within the load height range, and the protective capacity of the surrounding rock within the safety protection thickness range, w1, w2, and w3 are each taken as 1. If their protective capacity is partially considered, w1, w2, and w3 can be taken as values ​​between 0 and 1.

[0021] In a second aspect, the present invention provides an electronic device comprising: one or more processors; and a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the method for calculating the minimum safe detection distance for tunnel geological prediction advance detection provided in the first aspect of the present invention.

[0022] In a third aspect, the present invention provides a computer-readable medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method for calculating the minimum safe detection distance for tunnel geological prediction and advance detection provided in the first aspect of the present invention.

[0023] The beneficial effects of this invention are:

[0024] 1. This invention is based on a quantitative estimation method for the potential safety impact range of different factors such as construction disturbance, surrounding rock load, and water-bearing structure. It constructs an estimation method and index system for the minimum safe detection distance of sudden surge disasters in mountainous highway tunnels using transient electromagnetic method based on the cumulative impact range, providing a basis for the management and control of sudden surge disasters in mountainous highway tunnels.

[0025] 2. The method of this invention comprehensively and systematically considers safety influencing factors. Combining the characteristics of tunnel construction, it considers the quantitative characterization of three major safety influencing factors: construction disturbance, the influence range of surrounding rock load, and the potential squeezing and breakthrough influence range of water-bearing structures. Utilizing existing methods for calculating tunnel engineering disturbance thickness, surrounding rock load height, and the balance equation between the external load of water-bearing structures and the resistance of the protective layer soil and rock, a quantitative estimation method and index system for the potential safety influence range caused by factors such as construction disturbance, surrounding rock load, and water pressure of water-bearing structures are constructed. This method is quantitative, simple, and easy to calculate, providing safety control indicators and quantitative guidance for advanced geological prediction of tunnel inrush disasters. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a flowchart of the method for calculating the minimum safe detection distance for tunnel geological prediction and advance detection according to the present invention;

[0028] Figure 2 The curve showing the relationship between uniaxial compressive strength and engineering disturbance thickness;

[0029] Figure 3 This is a longitudinal section view of the location of a tunnel burst disaster, as shown in the example.

[0030] Figure 4 This is a schematic diagram of the structure of an electronic device in some embodiments of the present invention. Detailed Implementation

[0031] The technical solutions of various embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] See Figure 1 In a first aspect of the present invention, a method for calculating the minimum safe detection distance for tunnel geological prediction and advance detection is provided, comprising the following steps:

[0034] Based on the saturated uniaxial compressive strength R of rock c The estimated thickness of the engineering disturbance, h1, is obtained by calculation;

[0035] Based on the surrounding rock conditions of the tunnel, the estimated load height h2 is calculated;

[0036] Based on the tunnel rock and water content conditions, the estimated safety protection thickness h3 is calculated;

[0037] Based on the estimated thickness of engineering disturbance h1, the estimated height of load h2, and the estimated thickness of safety protection h3, the minimum safe detection distance for tunnel geological prediction advance detection is determined as H = w1·h1 + w2·h2 + w3·h3, where w1, w2, and w3 are weighting coefficients.

[0038] It should be noted that the minimum safe detection distance H for tunnel geological prediction and advanced detection can be selected based on different considerations when calculating. For example, under conservative conditions, if the protective capacity of the surrounding rock within the engineering disturbance thickness range, the protective capacity of the surrounding rock within the load height range, and the protective capacity of the surrounding rock within the safety protection thickness range are not considered, then w1, w2, and w3 can be 1 respectively. If the protective capacity is partially considered, then w1, w2, and w3 can be values ​​between 0 and 1.

[0039] In some embodiments, the rock saturated uniaxial compressive strength R c The calculated engineering disturbance thickness estimate, taking into account lithological hardness, includes:

[0040] Based on the saturated uniaxial compressive strength R of the rock c Corresponding to the qualitative classification of rock hardness, different boundary strength values ​​are defined for the rock, and curves showing the relationship between uniaxial compressive strength and engineering disturbance thickness are plotted, such as... Figure 2As shown, rocks are classified into five levels from hard to soft using saturated uniaxial compressive strength: hard, relatively hard, relatively soft, soft, and extremely soft, with limit strength values ​​of 60 MPa, 30 MPa, 15 MPa, and 5 MPa, respectively. The disturbance thickness varies depending on the hardness of the surrounding rock. Generally, for Grade V surrounding rock, the upper limit of the saturated uniaxial compressive strength is 5 MPa, and the disturbance range can reach 6-8 m; for Grade IV surrounding rock, the upper limit of the saturated uniaxial compressive strength is 15 MPa, and the disturbance range can reach 4-6 m; for Grade III surrounding rock, the upper limit of the saturated uniaxial compressive strength is 30 MPa, and the disturbance range can reach 2-4 m; for Grade II surrounding rock, the upper limit of the saturated uniaxial compressive strength is 60 MPa, and the disturbance range can reach 1-2 m. Surrounding rock with a saturated uniaxial compressive strength greater than 60 MPa is Grade I, with a disturbance range of 0-1 m. By fitting the upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range, we can obtain the engineering disturbance thickness estimation formula. That is, the engineering disturbance thickness estimation formula is obtained by fitting the curve of the relationship between the uniaxial compressive strength and the engineering disturbance thickness. In the formula, h1 is the engineering disturbance thickness, in meters; R c The value is the saturated uniaxial compressive strength of the rock, in MPa; 33.82 is in MPa·m.

[0041] In some specific embodiments, the above-mentioned engineering disturbance thickness estimation is achieved by substituting the saturated uniaxial compressive strength of the surrounding rock at the tunnel face into the R value in the h1 formula. c Calculated.

[0042] In some embodiments, the estimated load height is calculated based on the surrounding rock conditions of the tunnel, including:

[0043] Based on the conditions for the generation of surrounding rock pressure, the estimated load height h2 is calculated to be 0.45 × 2. s-1 ×[1+i(B-5)], where s is the surrounding rock grade, taking integers from 1 to 5; B is the tunnel width, in meters; i is the rate of increase or decrease in surrounding rock pressure for every 1 meter increase or decrease in tunnel width. If B < 5, then i = 0.2; if 5 ≤ B < 14, then i = 0.1; if 14 ≤ B < 25, then i = 0.07 for pilot tunnel excavation, and i = 0.12 for step-up or single-stage excavation.

[0044] In some embodiments, the security protection thickness estimate

[0045] In the formula, γ is the specific gravity of water, in kN / m³. 3 h represents the static water pressure inside the aquifer, in kPa; S1 represents the vertical projection of the bottom of the aquifer, in meters. 2 c represents the cohesion of the protective layer, in kPa; C1 represents the perimeter of the protective layer projected along the bottom of the water-bearing structure, in meters.

[0046] Example

[0047] like Figure 3 As shown, a certain tunnel is a long, two-way, six-lane separated tunnel with a flat shape, a width of 17.15m, a height of 11.68m, and a maximum burial depth of 731m. On XXXX, during construction of the left tunnel, at the working face ZK281+955, three circumferential cracks were discovered in the initial support at ZK281+942 in the morning. On the afternoon of XXXX, at the same location, the arch subsided and a section of the arch collapsed. Subsequently, on the 27th, 28th, 29th, and 30th of the same month, and the 10th of the following month, eight sudden surge disasters occurred, with the largest surge volume being 28,000 m³ on the 10th of the following month. 3 .

[0048] Based on on-site testing and analysis, the lithology of the tunnel face where the tunnel surge disaster occurred is loose, strongly weathered granite porphyry. The tunnel top is strongly weathered limestone interbedded with some granite porphyry, with a surrounding rock grade of V1 and a saturated uniaxial compressive strength of 13 MPa. Supplementary exploration determined that the top 9m of the tunnel is completely weathered granite containing diabase xenoliths; the next 22m is a solution cavity, with 11m of gravelly sand and soil deposited at the bottom and 11m of water-bearing cavities; the next 20m is moderately weathered migmatite; and the area from the top to the ground is mainly limestone.

[0049] For this tunnel, the saturated uniaxial compressive strength R of the surrounding rock at the tunnel top is... c =13MPa Substitute into the formula The calculated disturbance thickness h1 for this tunnel section is 2.6m;

[0050] The tunnel width B = 17.15m, the surrounding rock grade S = 5, and i = 0.12. Substituting these values ​​into the formula, h² = 0.45 × 2 s-1 ×[1+i(B-5)], the calculated load height h2 is 17.7m;

[0051] The cohesion of the bottom sedimentary sand is almost zero, so even a slight water level in the cavity can cause sudden collapse. Here, using the strength parameter c = 50 kPa of strongly weathered granite, a cavity water level of 11 m, and a circular wall projection area with a radius of 17 m, we have S1 = 907.5 m² and C1 = 106.8 m. Substituting these values ​​into the formula... The calculated value is h3 = 18.7 m;

[0052] Substituting the calculation results into the formula H=w1·h1+w2·h2+w3·h3, we obtain that the minimum safe distance H for geological prediction advance detection is 39.0m; in this embodiment, the weighting coefficients w1, w2, and w3 are each set to 1.

[0053] The combined length of the top rock and soil layers at the location of the tunnel surge disaster was 20m, far less than the minimum safe detection distance of 39.0m, which was the main cause of the tunnel surge disaster. Furthermore, the detection range of ground-penetrating radar is generally around 20m, and the development of this cavity was precisely at the upper limit of its effective detection range, which also explains the failure of geological prediction and detection for this section of the tunnel, thus failing to provide effective early warning and forecasting for the project.

[0054] The effective detection range is determined by the performance of the equipment used, and is unrelated to experience or quantitative methods. It is determined by the equipment itself. Currently, short-range high-precision detection generally uses ground-penetrating radar, with a detection range of about 10m for soil and about 20m for rock. Once the water-bearing structure reaches a certain scale, this thickness is difficult to provide effective safety protection, and problems usually occur outside the detection range or at the upper limit. Long-range detection generally uses TSP, with a detection range of over 100m. Its limitation is that it is difficult to radiate to the sides or top of the tunnel. Also, elastic waves are more sensitive to weak layers, but not necessarily to water-bearing structures, so it has its limitations.

[0055] Therefore, traditional methods lack clear quantitative physical and mechanical mechanisms to support the detection distance, and vary from person to person and from equipment to equipment, thus lacking universality and applicability.

[0056] Therefore, for advanced geological exploration of water-bearing structures in tunnels, the medium-to-long-range transient electromagnetic method can be considered to ensure that the effective detection range covers or exceeds the minimum safe detection distance. This is the only way to ensure effective control of the safety risks of tunnel inrushes caused by water-bearing structures.

[0057] refer to Figure 4 In a second aspect, the present invention provides an electronic device comprising: one or more processors; and a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the method for calculating the minimum safe distance for geological forecast advance detection according to the first aspect of the present invention.

[0058] The electronic device 100 may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 101, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 102 or a program loaded from a storage device 108 into a random access memory (RAM) 103. The RAM 103 also stores various programs and data required for the operation of the electronic device 100. The processing unit 101, ROM 102, and RAM 103 are interconnected via a bus 104. An input / output (I / O) interface 105 is also connected to the bus 104.

[0059] Typically, the following devices can be connected to I / O interface 105: input devices 106 including, for example, touch screens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 107 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 108 including, for example, hard disks, etc.; and communication devices 109. Communication device 109 allows electronic device 100 to communicate wirelessly or wiredly with other devices to exchange data.

[0060] Although Figure 4 An electronic device 100 with various devices is shown; however, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively. Figure 4 Each box shown can represent a device or multiple devices as needed.

[0061] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication device 109, or installed from storage device 108, or installed from ROM 102. When the computer program is executed by processing device 101, it performs the functions defined in the methods of embodiments of this disclosure.

[0062] It should be noted that the computer-readable medium described in the embodiments of this disclosure may be a computer-readable signal medium or a computer-readable storage medium or any combination thereof.

[0063] Computer-readable storage media may be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof.

[0064] More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0065] In embodiments of this disclosure, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used or combined with an instruction execution system, apparatus, or device. In embodiments of this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof.

[0066] A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0067] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device. The aforementioned computer-readable medium carries one or more computer programs that, when executed by the electronic device, enable the electronic device to write computer program code for performing the operations of the embodiments of this disclosure in one or more programming languages ​​or combinations thereof. The programming languages ​​include object-oriented programming languages—such as Java, Smalltalk, C++, and Python—and conventional procedural programming languages—such as the "C" language or similar programming languages. The program code may be executed entirely on a user's computer, partially on a user's computer, as a standalone software package, partially on a user's computer and partially on a remote computer, or entirely on a remote computer or server.

[0068] In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0069] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function.

[0070] It should also be noted that in some alternative implementations, the functions marked in the boxes may occur in a different order than those shown in the accompanying drawings. For example, two consecutively indicated boxes may actually be executed in essentially parallel order, or sometimes in reverse order, depending on the functions involved.

[0071] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for calculating the minimum safe detection distance for advanced detection in tunnel geological prediction, characterized in that, Includes the following steps: Based on the saturated uniaxial compressive strength R of rock c The estimated thickness h1 of the engineering disturbance is obtained by calculation; Based on the surrounding rock conditions of the tunnel, the estimated load height h2 is calculated; Based on the tunnel rock and water content conditions, the estimated safety protection thickness h3 is calculated; Based on the estimated thickness of engineering disturbance h1, the estimated height of load h2, and the estimated thickness of safety protection h3, the minimum safe detection distance for tunnel geological prediction advance detection is determined as H = w1·h1 + w2·h2 + w3·h3, where w1, w2, and w3 are weighting coefficients, respectively. The rock saturated uniaxial compressive strength R c The calculated engineering disturbance thickness estimate, taking into account lithological hardness, includes: Based on the saturated uniaxial compressive strength R of the rock c Corresponding to the qualitative classification of rock hardness, different boundary strength values ​​are defined for the rock, and the relationship curve between uniaxial compressive strength and engineering disturbance thickness is plotted. Based on the fitting of this uniaxial compressive strength and engineering disturbance thickness relationship curve, the estimated engineering disturbance thickness h1 is obtained. The specific method for obtaining the engineering disturbance thickness estimate by fitting the curve of the relationship between uniaxial compressive strength and engineering disturbance thickness is as follows: using the saturated uniaxial compressive strength, the rock is divided into 5 levels from hard to soft: hard, relatively hard, relatively soft, soft, and extremely soft, with the limit strength values ​​being 60MPa, 30MPa, 15MPa, and 5MPa, respectively. The engineering disturbance thickness estimate formula can be obtained by fitting the upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range. The formula for estimating the thickness of the engineering disturbance is as follows: In the formula, h1 is the engineering disturbance thickness, in meters; R c The value represents the saturated uniaxial compressive strength of rock, in MPa; 33.82 is in MPa·m. The estimated load height calculated based on the tunnel surrounding rock conditions includes: Based on the conditions for the generation of surrounding rock pressure, the estimated load height is calculated. In the formula, s is the surrounding rock grade, which is an integer from 1 to 5; B is the tunnel width, in meters; i is the rate of increase or decrease of surrounding rock pressure when the tunnel width increases or decreases by 1 meter. If B < 5, then i = 0.2; if 5 ≤ B < 14, then i = 0.1; if 14 ≤ B < 25, then i = 0.07 for pilot tunnel excavation, and i = 0.12 for step excavation or single excavation.

2. The method for calculating the minimum safe detection distance for tunnel geological prediction and advanced detection according to claim 1, characterized in that, Substituting the saturated uniaxial compressive strength of the surrounding rock at the tunnel face into R in the h1 formula. c The estimated thickness of the engineering disturbance can then be obtained.

3. The method for calculating the minimum safe detection distance for tunnel geological prediction and advanced detection according to claim 1, characterized in that, Under conservative conditions, without considering the protective capacity of the surrounding rock within the engineering disturbance thickness range, the protective capacity of the surrounding rock within the load height range, and the protective capacity of the surrounding rock within the safety protection thickness range, w1, w2, and w3 all take values ​​of 1; if their protective capacity is partially considered, then w1, w2, and w3 take values ​​between 0 and 1.

4. An electronic device, comprising: One or more processors; A storage device for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the method for calculating the minimum safe detection distance for tunnel geological prediction advance detection as described in any one of claims 1 to 3.

5. A computer-readable medium having a computer program stored thereon, wherein, When the computer program is executed by the processor, it implements the method for calculating the minimum safe detection distance for tunnel geological prediction and advanced detection as described in any one of claims 1 to 3.

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