Tunnel geological forecast advanced detection minimum safety detection distance calculation method

Abstract

The invention relates to a tunnel geological forecast advanced detection minimum safety detection distance calculation method, which comprises the following steps: calculating an engineering disturbance thickness estimated value h1 based on rock saturated uniaxial compressive strength Rc; based on the tunnel surrounding rock condition, a load height estimated value h2 is obtained through calculation; based on tunnel rock and water content conditions, a safety protection thickness estimated value h3 is obtained through calculation; and based on the engineering disturbance thickness estimation value h1, the load height estimation value h2 and the safety protection thickness estimation value h3, determining the tunnel geological forecast advanced detection minimum safety detection distance H = w1 * h1 + w2 * h2 + w3 * h3. According to the calculation method, through a potential safety influence range quantitative valuation method based on different elements such as construction disturbance, surrounding rock load and water-containing structure, a mountainous area highway tunnel inrush disaster transient electromagnetic method geological forecast advanced detection minimum safety detection distance valuation method based on an accumulated influence range is constructed; and a basis can be provided for mountain highway tunnel inrush disaster management and control.

Description

Technical Field

[0001] The invention belongs to the technical field of geological detection, and in particular relates to a method for calculating a minimum safe detection distance for advance detection of tunnel geological prediction. Background Art

[0002] In the construction of mountain highway tunnels, in order to prevent tunnel surge disasters, advanced geological exploration is a vital link. Most surge disasters are mainly caused by technical limitations and insufficient coverage of the detection distance. The current mainstream advanced geological forecast mainly relies on the effective detection distance of the equipment for front-to-back detection work. The minimum safe detection distance is usually based on experience, which causes certain surge safety hazards. Therefore, it is urgent to propose a quantifiable method for estimating the minimum safe detection distance of tunnel advanced geological detection to provide support for the prevention and control of tunnel geological disaster risks.

[0003] From the perspective of the occurrence of tunnel sudden surge disasters, the current method of combining geological radar short-range detection and TSP long-range detection is basically effective in controlling sudden surge disasters caused by water-containing structures in front of the face, but the control effect on the upper and side structures is relatively poor. At the same time, the mismatch between radar short-sightedness and effective safety protection thickness is the root cause of most disasters.

[0004] At present, the valuation method of the minimum safe detection distance is usually based on comprehensive consideration of multiple factors such as geological conditions, detection technology, and construction requirements. Common valuation methods at present: Empirical formula method: Based on historical data and engineering experience, an empirical formula suitable for specific geological conditions and detection technology is summarized. This method is simple and easy to implement, but it is greatly restricted by regionality and technical level. Numerical simulation method: Using computer simulation technology, the geological changes during tunnel construction are numerically simulated to obtain the minimum safe detection distance. This method can take into account a variety of complex factors, but the calculation amount is large and the model accuracy requirements are high. Risk assessment method: Risk assessment is carried out based on geological conditions, construction difficulty, safety risks and other factors, and the minimum safe detection distance is determined based on the assessment results. This method can take into account a variety of factors, but the assessment process is relatively complex and requires rich professional knowledge and experience. Therefore, there is an urgent need to be able to more effectively determine the minimum safe detection distance for tunnel geological forecast advance detection. Summary of the invention

[0005] The present invention proposes a method for calculating the minimum safe detection distance for advance detection of tunnel geological prediction, and a quantitative valuation method for the potential safety impact range of different factors such as construction disturbance, surrounding rock load, and water-containing structure. A method and index system for estimating the minimum safe detection distance for advance geological prediction of sudden surge disasters in mountainous highway tunnels using the transient electromagnetic method based on the cumulative impact range are constructed to provide a basis for the management and control of sudden surge disasters in mountainous highway tunnels.

[0006] A first aspect of the present invention provides a method for calculating a minimum safe detection distance for advance detection of tunnel geology prediction, comprising the following steps:

[0007] Based on the saturated uniaxial compressive strength of rock R c , calculate the estimated engineering disturbance thickness h1;

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

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

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

[0011] As a further limitation of the present invention, the rock saturated uniaxial compressive strength R c , the estimated engineering disturbance thickness considering the rock hardness is calculated including:

[0012] According to the saturated uniaxial compressive strength of rock R c Corresponding to the qualitatively classified rock hardness, different limit strength values ​​are divided into rocks, and the relationship curve between uniaxial compressive strength and engineering disturbance thickness is drawn. Based on the relationship curve between uniaxial compressive strength and engineering disturbance thickness, the estimated engineering disturbance thickness h1 is obtained by fitting.

[0013] As a further limitation of the present invention, the specific method for fitting the relationship curve between the uniaxial compressive strength and the engineering disturbance thickness to obtain the estimation of the engineering disturbance thickness is: using the saturated uniaxial compressive strength to divide the rock from hard to soft into 5 levels: hard, relatively hard, relatively soft, soft, and extremely soft, with the limit strength values ​​being 60MPa, 30MPa, 15MPa, and 5MPa, respectively. The upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range are fitted to obtain the formula for estimating the engineering disturbance thickness.

[0014] As a further limitation of the present invention, the engineering disturbance thickness estimation formula is: Where h1 is the engineering disturbance thickness, unit: m; R c is the saturated uniaxial compressive strength of rock, unit is MPa; the unit of 33.82 is MPa.m.

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

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

[0017] According to the conditions for the generation of surrounding rock pressure, the load height estimate h2 = 0.45 × 2 s-1 ×[1+i(B-5)], where s is the surrounding rock grade, an integer of 1-5; B is the tunnel width, in m; i is the rate of increase or decrease of surrounding rock pressure when the tunnel width increases or decreases by 1 m, if B<5, i=0.2; if 5≤B<14, i=0.1; if 14≤B<25, if excavation is carried out in separate pilot tunnels, i=0.07; if excavation is carried out in upper and lower steps or in one step, i=0.12.

[0018] As a further limitation of the present invention, the safety protection thickness estimation

[0019] Where γ is the specific gravity of water, unit is kN / m 3 ; h is the static water pressure of the fluid inside the water-bearing structure, unit is kPa; S1 is the vertical projection surface of the bottom of the water-bearing structure, unit is m 2 ; c is the cohesion of the protective layer, unit is kPa; C1 is the circumference of the projection range of the protective layer along the bottom of the water-bearing structure, unit is m.

[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, without considering the protective capacity of the surrounding rock within the load height range, and without considering the protective capacity of the surrounding rock within the safety protection thickness range, the values ​​of w1, w2, and w3 are respectively 1. If the protective capacity is partially considered, w1, w2, and w3 can take values ​​between 0 and 1.

[0021] The second aspect of the present invention provides an electronic device, comprising: one or more processors; a storage device for storing one or more programs, 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 advance detection of tunnel geological prediction provided in the first aspect of the present invention.

[0022] The third aspect of 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 advance detection of tunnel geology prediction provided in the first aspect of the present invention.

[0023] The beneficial effects of the present invention are:

[0024] 1. The present invention is based on a quantitative valuation method for the potential safety impact range of different factors such as construction disturbance, surrounding rock load, and water-containing structure, and constructs a minimum safe detection distance valuation method and index system for advanced geological prediction of sudden surge disasters in mountainous highway tunnels 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 the present invention considers safety influencing factors comprehensively and systematically, and combines the characteristics of tunnel construction to consider the quantitative characterization of the three main safety influencing factors, namely, construction disturbance, surrounding rock load influence range, and potential squeeze breakthrough influence range of water-containing structures, which are closely related to these factors. By utilizing the existing tunnel engineering disturbance thickness calculation method, surrounding rock load height calculation method, and the balance equation between the external load of the water-containing structure and the resistance of the rock and soil mass of the protective layer, a quantitative valuation method and index system for the potential safety impact range caused by influencing factors such as construction disturbance, surrounding rock load, and water pressure of the water-containing structure are constructed. The method is quantitative, simple, and easy to calculate, and provides safety control indicators and quantitative guidance for the advanced geological prediction of tunnel sudden surge disasters. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a flow chart of the method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction of the present invention;

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

[0029] Figure 3 A longitudinal section view of a tunnel surge disaster location in an embodiment;

[0030] Figure 4 It is a schematic diagram of the structure of an electronic device in some embodiments of the present invention. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions of various embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms “first”, “second” and “third” are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

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

[0034] Based on the saturated uniaxial compressive strength of rock R c , calculate the estimated engineering disturbance thickness h1;

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

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

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

[0038] It should be noted that when calculating the minimum safe detection distance H for tunnel geological forecast advance detection, it can be selected based on different considerations; for example, under conservative conditions, without considering the protective capacity of the surrounding rock in the engineering disturbance thickness range, without considering the protective capacity of the surrounding rock in the load height range, and without considering the protective capacity of the surrounding rock in the safety protection thickness range, then w1, w2, and w3 are 1 respectively; if the protective capacity is partially considered, w1, w2, and w3 can take values ​​between 0 and 1.

[0039] In some embodiments, the rock saturated uniaxial compressive strength R c , the estimated engineering disturbance thickness considering the rock hardness is calculated including:

[0040] According to the saturated uniaxial compressive strength of rock R c According to the relationship between the rock hardness and the qualitative classification, the rock is divided into different limit strength values, and the relationship curve between the uniaxial compressive strength and the engineering disturbance thickness is drawn, such as Figure 2As shown, the saturated uniaxial compressive strength is used to divide rocks into five levels from hard to soft, namely hard, relatively hard, relatively soft, soft, and extremely soft, and the limit strength values ​​are 60MPa, 30MPa, 15MPa, and 5MPa, respectively. Different soft and hard surrounding rock grades correspond to different disturbance thicknesses. Generally, the upper limit saturated uniaxial compressive strength corresponding to the fifth-level surrounding rock is 5MPa, and the disturbance range can reach 6-8m; the upper limit saturated uniaxial compressive strength corresponding to the fourth-level surrounding rock is 15MPa, and the disturbance range can reach 4-6m; the upper limit saturated uniaxial compressive strength corresponding to the third-level surrounding rock is 30MPa, and the disturbance range can reach 2-4m; the upper limit saturated uniaxial compressive strength corresponding to the second-level surrounding rock is 60MPa, and the disturbance range can reach 1-2m. If the saturated uniaxial compressive strength is greater than 60MPa, it is the first-level surrounding rock, and the disturbance range is 0-1m. The upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range can be fitted to obtain the engineering disturbance thickness estimation formula, that is, based on the relationship curve fitting between the uniaxial compressive strength and the engineering disturbance thickness, the engineering disturbance thickness estimation formula is obtained: Where h1 is the engineering disturbance thickness, unit: m; R c is the saturated uniaxial compressive strength of rock, MPa; the unit of 33.82 is MPa.m.

[0041] In some specific embodiments, the above engineering disturbance thickness estimation is to substitute the saturated uniaxial compressive strength of the surrounding rock of the tunnel face into R in the h1 formula. c Calculated.

[0042] In some embodiments, based on the surrounding rock conditions of the tunnel, calculating the load height estimate includes:

[0043] According to the conditions for the generation of surrounding rock pressure, the load height estimate h2 = 0.45 × 2 s-1 ×[1+i(B-5)], where s is the surrounding rock grade, an integer of 1-5; B is the tunnel width, in m; i is the rate of increase or decrease of surrounding rock pressure when the tunnel width increases or decreases by 1 m, if B<5, i=0.2; if 5≤B<14, i=0.1; if 14≤B<25, if excavation is carried out in separate pilot tunnels, i=0.07; if excavation is carried out in upper and lower steps or in one step, i=0.12.

[0044] In some embodiments, the safety protection thickness estimation

[0045] Where γ is the specific gravity of water, unit is kN / m 3 ; h is the static water pressure of the fluid inside the water-bearing structure, unit is kPa; S1 is the vertical projection surface of the bottom of the water-bearing structure, unit is m 2 ; c is the cohesion of the protective layer, unit is kPa; C1 is the circumference of the projection range of the protective layer along the bottom of the water-bearing structure, unit is m.

[0046] Example

[0047] like Figure 3 As shown in the figure, a certain tunnel is a two-way 6-lane separated extra-long tunnel, with a flat tunnel hole width of 17.15m, height of 11.68m and maximum burial depth of 731m. On Xth month 24th, XXXX, the left section of the tunnel was constructed to the heading face ZK281+955. In the morning, three circumferential cracks were found in the initial support at the ZK281+942 position; on the afternoon of Xth month 26th, XXXX, the arch sank and blocks fell at the same position; subsequently, on the 27th, 28th, 29th, 30th of the same month and the 10th of the next month, there were 8 sudden surge disasters, with the largest sudden surge being 28,000m on the 10th of the next month. 3 .

[0048] Based on field detection and analysis, the rock type of the tunnel face where the sudden surge disaster occurred is loose, strongly weathered granite porphyry, the top of the tunnel is strongly weathered limestone intercalated with some granite porphyry, the surrounding rock grade is V1, and the saturated uniaxial compressive strength is 13MPa; supplementary exploration determined that the top of the tunnel is 9m wide and is fully weathered granite containing diabase xenoliths; the next 22m up is a solution cavity, of which the bottom is deposited with 11m of gravel and sand, and 11m of water-containing cavity; the next 20m is moderately weathered mixed rock; and the next up to the ground is basically limestone.

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

[0050] Tunnel width B = 17.15m, surrounding rock grade S = 5, i is 0.12, substitute 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 sediment is almost 0, so a little water level in the cavity can cause sudden damage. Here, the strength parameter of strongly weathered granite is c = 50kPa, the cavity water level is 11m, and the wall projection area is a circle with a radius of 17m, then S1 = 907.5m2, C1 = 106.8m, substitute into the formula The calculation results show that h3 = 18.7m;

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

[0053] The top rock and soil layers of the tunnel surge disaster location are 20m in total, which is far less than the minimum safe detection distance of 39.0m, which is the main cause of the tunnel surge disaster. In addition, the detection distance of the geological radar is generally about 20m, and the development of the karst cavity is just at the upper limit of its effective detection range, which is also the reason for the failure of geological forecast detection in this tunnel section, and no effective early warning forecast is provided for the project.

[0054] The effective detection range is determined according to the performance of the equipment used. It has nothing to do with experience or quantification. It is a detection range determined by the equipment. At present, short-distance high-precision detection generally uses geological radar. The detection distance for soil is about 10m, and the detection distance for rock is about 20m. Once the water-bearing structure reaches a certain scale, this thickness is difficult to provide effective safety protection. Generally, problems are caused outside the detection range or at the upper limit. Long-distance detection generally uses TSP, and the detection distance is generally more than 100m. The limitation is that it is difficult to radiate the sides or top of the tunnel. At the same time, elastic waves are more sensitive to weak layers, but not necessarily to water-bearing structures, so it has its limitations.

[0055] Therefore, the traditional method has no clear quantitative physical and mechanical mechanism to support the detection distance. It varies from person to person and from device to device, and is not universal or transferable.

[0056] Therefore, for the advance geological survey of tunnel water-containing structures, the medium and long-range transient electromagnetic method can be considered to ensure that the effective detection range covers or exceeds the minimum safe detection distance, so as to ensure the effective control of the water-containing structure to the tunnel sudden surge safety risk.

[0057] refer to Figure 4 According to a second aspect of the present invention, an electronic device is provided, comprising: one or more processors; 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 advance detection of geological prediction according to the first aspect of the present invention.

[0058] Among them, the electronic device 100 may include a processing device (such as 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 to a random access memory (RAM) 103. In the RAM 103, various programs and data required for the operation of the electronic device 100 are also stored. The processing device 101, the ROM 102, and the RAM 103 are connected to each other via a bus 104. An input / output (I / O) interface 105 is also connected to the bus 104.

[0059] The following devices may be connected to the I / O interface 105 in general: an input device 106 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 107 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 108 including, for example, a hard disk, etc.; and a communication device 109. The communication device 109 may allow the electronic device 100 to communicate with other devices wirelessly or by wire to exchange data.

[0060] Although Figure 4 The electronic device 100 is shown with various devices, but it should be understood that it is not required to implement or possess all the devices shown. More or fewer devices may be implemented or possessed instead. Figure 4 Each block shown in the figure may represent one device, or may represent multiple devices as required.

[0061] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication device 109, or installed from the storage device 108, or installed from the ROM 102. When the computer program is executed by the processing device 101, the above-mentioned functions defined in the method of the embodiment of the present disclosure are executed.

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

[0063] A computer readable storage medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the foregoing.

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

[0065] In an embodiment of the present disclosure, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device. In an embodiment of the present disclosure, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the foregoing.

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

[0067] The computer-readable medium may be included in the electronic device; or it may exist independently without being assembled into the electronic device. The computer-readable medium carries one or more computer programs. When the one or more programs are executed by the electronic device, the electronic device can be written in one or more programming languages ​​or a combination thereof to write computer program codes for performing the operations of the embodiments of the present disclosure. The programming languages ​​include object-oriented programming languages, such as Java, Smalltalk, C++, Python, and conventional procedural programming languages, such as "C" language or similar programming languages. The program code may be executed completely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or completely on a remote computer or server.

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

[0069] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, which contains 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 blocks may also occur in a different order than that marked in the accompanying drawings. For example, two blocks represented in succession may actually be executed substantially in parallel, and they may sometimes be executed in the opposite order, depending on the functions involved.

[0071] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction, characterized in that: The following steps are involved: Based on the saturated uniaxial compressive strength of rock R c , calculate the estimated engineering disturbance thickness h1; Based on the surrounding rock conditions of the tunnel, the estimated load height h2 is calculated; Based on the rock and water content of the tunnel, the estimated safety protection thickness h3 is calculated; Based on the engineering disturbance thickness estimation h1, load height estimation h2, and safety protection thickness estimation h3, the minimum safe detection distance H=w1·h1+w2·h2+w3·h3 for tunnel geological forecast advance detection is determined, where w1, w2, and w3 are weighting coefficients respectively.

2. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 1 is characterized in that: The saturated uniaxial compressive strength of rock R c , the estimated engineering disturbance thickness considering the rock hardness is calculated including: According to the saturated uniaxial compressive strength of rock R c Corresponding to the qualitatively classified rock hardness, different limit strength values ​​are divided into rocks, and the relationship curve between uniaxial compressive strength and engineering disturbance thickness is drawn. Based on the relationship curve between uniaxial compressive strength and engineering disturbance thickness, the estimated engineering disturbance thickness h1 is obtained by fitting.

3. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 2 is characterized in that: The specific method for fitting the relationship curve between the uniaxial compressive strength and the engineering disturbance thickness to obtain the estimated engineering disturbance thickness is as follows: using the saturated uniaxial compressive strength to divide the rock into five levels from hard to soft, namely hard, relatively hard, relatively soft, soft, and extremely soft, with the limit strength values ​​being 60MPa, 30MPa, 15MPa, and 5MPa, respectively. The upper limit of the saturated uniaxial compressive strength and the upper limit of the disturbance range are fitted to obtain the formula for estimating the engineering disturbance thickness.

4. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 3 is characterized in that: The engineering disturbance thickness estimation formula is: Where h1 is the engineering disturbance thickness, unit: m; R c is the saturated uniaxial compressive strength of rock, unit is MPa; the unit of 33.82 is MPa.m.

5. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 3 is characterized in that: Substitute the saturated uniaxial compressive strength of the surrounding rock of the tunnel face into R in the h1 formula c The estimated thickness of the engineering disturbance can be obtained.

6. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 1 is characterized in that: The load height estimation calculated based on the tunnel surrounding rock conditions includes: According to the conditions for the generation of surrounding rock pressure, the load height estimate h2 = 0.45 × 2 s-1 ×[1+i(B-5)], where s is the surrounding rock grade, an integer of 1-5; B is the tunnel width, in m; i is the rate of increase or decrease of surrounding rock pressure when the tunnel width increases or decreases by 1 m, if B<5, i=0.2; if 5≤B<14, i=0.1; if 14≤B<25, if excavation is carried out in separate pilot tunnels, i=0.07; if excavation is carried out in upper and lower steps or in one step, i=0.

12.

7. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 1 is characterized in that: Estimated safety protection thickness Where γ is the specific gravity of water, unit is kN / m 3 ; h is the static water pressure of the fluid inside the water-bearing structure, unit is kPa; S1 is the vertical projection surface of the bottom of the water-bearing structure, unit is m 2 ; c is the cohesion of the protective layer, unit is kPa; C1 is the circumference of the projection range of the protective layer along the bottom of the water-bearing structure, unit is m.

8. The method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction according to claim 1 is 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, the values ​​of w1, w2, and w3 are 1 respectively. If the protective capacity is partially considered, w1, w2, and w3 can take values ​​between 0 and 1.

9. An electronic device, comprising: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the one or more processors to implement the method for calculating the minimum safe detection distance for advance detection of tunnel geological prediction as described in any one of claims 1 to 8.

10. A computer readable medium having a computer program stored thereon, wherein: When the computer program is executed by a processor, the method for calculating the minimum safe detection distance for advance detection of tunnel geology prediction is implemented as described in any one of claims 1 to 8.

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