Method for judging grade of surrounding rock of underground engineering based on surface wave exploration

Abstract

The invention provides a method for judging the grade of underground engineering surrounding rock based on surface wave exploration, and relates to the technical field of underground engineering surrounding rock grade judgment, and the method comprises the steps: obtaining a first Rayleigh wave speed VR1 and a second Rayleigh wave speed VR2 corresponding to a target region; different lithologic interfaces are marked in the velocity profile maps corresponding to the VR1 and the VR2; the VR1 and the VR2 are converted into shear wave velocities; splicing the shear wave velocity data corresponding to the VR1 and the shear wave velocity data corresponding to the VR2 to obtain a continuous shear wave velocity profile; converting the transverse wave velocity profile to obtain a longitudinal wave velocity profile; calculating the uniaxial compressive strength of the rock according to the longitudinal wave velocity in the longitudinal wave velocity profile; a BQ contour map is generated according to the rock mass integrity index and the rock uniaxial compressive strength, and the surrounding rock grade is judged through the BQ contour map; according to the method, the construction period can be shortened, the cost is reduced, and the investigation quality and efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of underground engineering surrounding rock grade determination, and in particular to a method for determining the underground engineering surrounding rock grade based on surface wave exploration. Background Art

[0002] Excavation of underground projects such as tunnels and caverns is a complex engineering problem. As the most important basis for underground project design, surrounding rock grade significantly impacts the construction cost. Different surrounding rock grades also require different construction techniques, and inaccurate surrounding rock grade determination can pose significant safety risks. As underground projects continue to grow in depth, length, and scale, the geological challenges they face are becoming increasingly complex and diverse. To ensure construction safety, quality, and cost and schedule reductions, the demand for refined surrounding rock grade classification is becoming increasingly stringent. Rock masses, as geological bodies with diverse origins and complex structures, are characterized by heterogeneity and anisotropy. Even rock masses that are not far apart may have very different engineering properties. Therefore, in underground projects such as tunnels and underground caverns, due to the complex engineering geological conditions and frequent changes in surrounding rock, in order to effectively guide the construction of underground projects such as tunnels and underground caverns, when using drilling and sonic logging to determine the surrounding rock grade, if the borehole spacing is too large, it will lead to insufficient samples. At the same time, the boreholes only represent part of the stratum, and the test data may be highly discrete, which reduces the representativeness of drilling and sonic logging. Conventional drilling exploration methods require the arrangement of a certain number of boreholes. When the tunnel is buried deep, the borehole depth increases accordingly. The drilling equipment itself is heavy, the terrain is large, and the terrain is steep. In addition to being labor-intensive and costly, drilling construction is also very time-consuming. The construction of a single borehole can take from a few days to a month or even longer. In addition, because the land acquisition work has not been completed at the survey stage, drilling construction often involves compensation and coordination of construction land, which brings many uncertainties to the construction period. Therefore, the existing exploration method of determining surrounding rock grade mainly based on drilling has technical problems such as long construction period, high cost, low exploration quality and efficiency. Summary of the Invention

[0003] In view of the above technical problems, the technical solution adopted by the present invention is: According to a first aspect of the present application, a method for determining the grade of surrounding rock in an underground engineering project based on surface wave exploration is provided, the method comprising the following steps: S100, using an active surface wave method to obtain a first Rayleigh wave velocity VR1 corresponding to the target area; and using a micro-surface wave method to obtain a second Rayleigh wave velocity VR2 corresponding to the target area; wherein VR1 reflects the rock mass characteristics within a first depth range within the target area, and VR2 reflects the rock mass characteristics within a second depth range within the target area; the end depth of the first depth range is the starting depth of the second depth range; S200, obtains the Poisson's ratio, P-wave velocity, and S-wave velocity of each lithology through borehole velocity testing, and then converts VR1 and VR2 into S-wave velocity; S300, splicing the shear wave velocity data corresponding to VR1 and the shear wave velocity data corresponding to VR2 to obtain a continuous shear wave velocity profile; S400, converting the shear wave velocity profile to obtain a longitudinal wave velocity profile; S500, calculates the uniaxial compressive strength of rock based on the P-wave velocity in the P-wave velocity profile; S600 generates a BQ contour map based on the rock integrity index and the uniaxial compressive strength of the rock, and determines the surrounding rock grade through the BQ contour map.

[0004] Furthermore, step S100 includes the following steps: S110, surveying the target area, and based on the survey results, arranging ground survey lines, determining observation points and array parameters for active surface waves and micro-seismic surface waves; S120, marking the locations of the geophones and the exciting points on the survey line; S130 uses the active surface wave method to generate Rayleigh waves through excitation, and uses a detector to collect the dispersion curve to obtain VR1; S140 uses the micro-surface wave method to observe natural vibration signals through the array and obtain the Rayleigh wave phase velocity dispersion curve to obtain VR2.

[0005] Furthermore, step S200 includes the following steps: S210, obtain the longitudinal wave velocity V of the target lithologic rock mass through borehole wave velocity testing p and shear wave velocity V s ; Wherein, target lithology is any lithology; S220, according to V p and V s , determine the Poisson's ratio of the target lithology rock mass ; S230, according to μ d , convert VR1 and VR2 into shear wave velocities ; Where VR is the Rayleigh wave velocity corresponding to VR1 or VR2 in the velocity profile; η S is the conversion factor between Rayleigh wave and shear wave velocity; .

[0006] Furthermore, step S500 includes the following steps: S510, obtaining each preset rock uniaxial compressive strength prediction formula to obtain a rock uniaxial compressive strength prediction formula list A=(A1, A2, ..., A i ,…,A n), i=1, 2,...,n; among them, A i is the i-th preset rock uniaxial compressive strength prediction formula obtained, and n is the number of preset rock uniaxial compressive strength prediction formulas obtained; S520, substitute the P-wave velocity in the P-wave velocity profile into the uniaxial compressive strength prediction formula of each rock in A to obtain the prediction result list B corresponding to A = (B1, B2, ..., B i ,…,B n ); Among them, B i A i The corresponding prediction results; S530, determining the rock uniaxial compressive strength prediction formula corresponding to the prediction result in B that has the greatest similarity to the indoor test result as the target rock uniaxial compressive strength prediction formula corresponding to the target area; S540: Calculate the uniaxial compressive strength of the rock using a target rock uniaxial compressive strength prediction formula.

[0007] Furthermore, step S600 includes the following steps: S610, obtain the rock elastic longitudinal wave velocity V through in-hole acoustic logging pm And the rock elastic longitudinal wave velocity V is obtained through indoor tests pr ; S620, according to V pm and V pr , determine the rock mass integrity index K v =(V pm / V pr ) 2 ; S630, according to K v , determine the generation of BQ contour map; where the [BQ] value conforms to the following relationship: [BQ]=(100+3R c +250K v )-100(K1+K2+K3); Among them, R c is the uniaxial compressive strength of rock, K1, K2 and K3 are the correction coefficients for the influence of groundwater, main structural surface occurrence and initial stress state, respectively, which are obtained through field mapping, investigation and indoor tests.

[0008] The present invention has at least the following beneficial effects: The present invention's method for determining the surrounding rock grade of underground projects based on surface wave exploration employs active surface wave and micro-vibration surface wave methods to obtain Rayleigh wave velocities at different depths in the target area. Based on the verification of borehole marking lithologic interfaces and the calibration of Poisson's ratio, the shear wave velocity data at different depths is spliced into a continuous profile and converted into longitudinal wave velocity. The uniaxial compressive strength of the rock is then calculated and a BQ contour map is generated to determine the surrounding rock grade. This method, which eliminates the need for extensive drilling, can significantly shorten survey periods and reduce costs. It addresses the issues of limited sample size and discrete data in traditional drilling. It improves the accuracy of surrounding rock grading through continuous velocity profiles, reduces vegetation damage and carbon emissions through non-destructive testing, adapts to complex sites such as steep terrain, identifies high-risk sections in advance to reduce accident rates, and precisely controls support plans to save project costs. This method achieves high efficiency, accuracy, and environmental friendliness in determining the surrounding rock grade of underground projects, thereby shortening construction periods, reducing costs, and improving survey quality and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 A flow chart of a method for determining the surrounding rock grade of an underground engineering project based on surface wave exploration provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0011] The following will clearly and completely describe the technical solutions in the 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, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0012] It should be noted that, based on this disclosure, those skilled in the art will appreciate that an aspect described herein can be implemented independently of any other aspect, and that two or more of these aspects can be combined in various ways. For example, any number of the aspects described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement such an apparatus and / or practice such a method.

[0013] The following will refer to Figure 1The flowchart of the method for determining the grade of the surrounding rock of an underground engineering based on surface wave exploration shown in FIG. 1 introduces a method for determining the grade of the surrounding rock of an underground engineering based on surface wave exploration.

[0014] The method for determining the grade of surrounding rock of an underground engineering project based on surface wave exploration may include the following steps: S100, using the active source surface wave method to obtain the first Rayleigh wave velocity VR1 corresponding to the target area; and using the micro-motion surface wave method to obtain the second Rayleigh wave velocity VR2 corresponding to the target area; wherein VR1 reflects the rock mass characteristics in the first depth range in the target area, and VR2 reflects the rock mass characteristics in the second depth range in the target area; the end depth of the first depth range is the starting depth of the second depth range.

[0015] In this embodiment, an active source surface wave method such as hammer shock is used to obtain a shallow portion, such as a first Rayleigh wave velocity VR1 of 0-50 m, and a micro-vibration surface wave method is used to obtain a deep portion, such as a second Rayleigh wave velocity VR2 of 50-200 m. The depth ranges of the two are connected, such as the end depth of VR1 at 50 m is the starting depth of VR2.

[0016] Explanation of the technical principle: The high-frequency signal of active surface waves is good at high-resolution detection in shallow areas, while the low-frequency signal of micro-motion surface waves is good at deep penetration, forming non-drilling data collection with full-depth coverage.

[0017] Furthermore, step S100 may include the following steps: S110 , surveying the target area, and based on the survey results, arranging ground survey lines, determining observation points and array parameters for active surface waves and micro-seismic surface waves.

[0018] Conduct on-site surveys of terrain, vegetation, and geological outcrops, and lay out ground survey lines, such as along the tunnel axis, to determine the spacing between the excitation points for active surface waves, such as 5 m, and the array radius for micro-seismic surface waves, such as 30 m. This step ensures that the survey lines cover the target area, taking into account both shallow detection requirements (i.e., active sources) and deep detection requirements (i.e., micro-seismic detection).

[0019] S120, mark the locations of the geophone and the exciting points on the survey line.

[0020] Mark the detector positions on the survey line, such as 24 detectors with a spacing of 5m and the excitation points, and establish a unified geographic coordinate system, such as the UTM coordinate system, to ensure spatial alignment of the data.

[0021] S130 uses the active surface wave method to generate Rayleigh waves through excitation, and uses a detector to collect the dispersion curve to obtain VR1.

[0022] Rayleigh waves are excited by hammering or source vehicles. The detector collects the signal and performs dispersion analysis to extract the Rayleigh wave velocity VR1 of different frequencies to form a shallow velocity profile.

[0023] S140 uses the micro-surface wave method to observe natural vibration signals through the array and obtain the Rayleigh wave phase velocity dispersion curve to obtain VR2.

[0024] By using a circular array, such as 6 stations, to observe natural vibrations for more than 30 minutes, the spatial autocorrelation method (SPAC) is used to calculate the Rayleigh wave phase velocity dispersion curve to obtain the deep velocity profile VR2.

[0025] Furthermore, the rock core identification results of a small number of verification boreholes, such as the boundaries between limestone and shale, can be used to mark the interface positions of different lithologies in the VR1 and VR2 velocity profiles; thereby establishing a correspondence between surface wave velocity data and actual geological formations, providing geological constraints for subsequent velocity conversion; it should be noted that those skilled in the art can, according to actual needs, use existing methods to mark different lithology interfaces in the velocity profiles corresponding to VR1 and VR2 based on the rock core identification results of the verification boreholes, and no further details will be given here.

[0026] S200 obtains the Poisson's ratio, P-wave velocity, and S-wave velocity of each lithology through borehole velocity testing, and then converts VR1 and VR2 into S-wave velocity.

[0027] The longitudinal and shear wave velocities of each rock type are obtained through borehole wave velocity testing, the Poisson's ratio is calculated, and then the Poisson's ratio is used to convert VR1 and VR2 into shear wave velocities; thus, the Rayleigh wave velocity measured by the surface wave is converted into the shear wave velocity required for the project, laying the foundation for the calculation of the longitudinal wave velocity.

[0028] Furthermore, step S200 may include the following steps: S210, obtain the longitudinal wave velocity V of the target lithologic rock mass through borehole wave velocity testing p and shear wave velocity V s ; Wherein, the target lithology is any lithology.

[0029] Perform acoustic logging in the verification borehole to obtain the rock mass longitudinal wave velocity V p and shear wave velocity V s Usually one drill hole is arranged every 100-500m, and the depth covers 5-10m below the excavation contour line.

[0030] S220, according to V p and V s , determine the Poisson's ratio of the target lithology rock mass .

[0031] The Poisson's ratio formula reflects the elastic characteristics of the rock mass. Different rock types, such as limestone and sandstone, each have a unique Poisson's ratio range. The Poisson's ratio can be obtained through on-site measurement of borehole wave velocity testing.

[0032] S230, according to μd , convert VR1 and VR2 into shear wave velocities ; Where VR is the Rayleigh wave velocity corresponding to VR1 or VR2 in the velocity profile; η S is the conversion factor between Rayleigh wave and shear wave velocity; .

[0033] The above steps have at least the following beneficial effects: Multi-physics calibration: Using the measured parameters of the borehole (V p 、V s ) Establish a mapping relationship between surface wave velocity and real rock mass parameters, eliminate the multi-solution problem of surface wave inversion, and improve the accuracy of velocity conversion.

[0034] Lithology-specific adaptation: Poisson's ratio is calibrated by lithology group to avoid velocity calculation deviation caused by a one-size-fits-all approach. This is particularly suitable for underground projects with complex and variable lithology.

[0035] S300 , splicing the shear wave velocity data corresponding to VR1 and the shear wave velocity data corresponding to VR2 to obtain a continuous shear wave velocity profile.

[0036] The shallow shear wave velocity corresponding to VR1 and the deep shear wave velocity corresponding to VR2 are weighted and merged at the depth connection point, such as 50m, with a gradual weighting of 80% for the shallow part and 20% for the deep part, to generate a continuous shear wave velocity profile. Kriging interpolation or triangulation interpolation can be used to eliminate blind spots in the shallow and deep parts of a single method, thus forming a continuous velocity field from 0 to 200m.

[0037] S400: Convert the shear wave velocity profile to obtain a longitudinal wave velocity profile.

[0038] Using Poisson's ratio, the shear wave velocity V s Converted to longitudinal wave velocity V p , and obtain the longitudinal wave velocity profile. The longitudinal wave velocity is used to calculate the rock integrity index K in GB / T50218 standard. v Required parameter for .

[0039] For strata with different lithologies, the Poisson's ratio of each stratum is substituted into the above formula: , and Invert the shear wave velocity profile of the formation and convert the shear wave velocity profile into a longitudinal wave velocity profile.

[0040] S500: Calculate the uniaxial compressive strength of rock based on the P-wave velocity in the P-wave velocity profile.

[0041] The uniaxial compressive strength of rock was calculated using several preset empirical formulas, and the formula with the smallest error was selected as the final prediction model by comparing the indoor test results.

[0042] Furthermore, step S500 may include the following steps: S510, obtaining each preset rock uniaxial compressive strength prediction formula to obtain a rock uniaxial compressive strength prediction formula list A=(A1, A2, ..., A i ,…,A n ), i=1, 2,...,n; among them, A i is the i-th preset rock uniaxial compressive strength prediction formula obtained, and n is the number of preset rock uniaxial compressive strength prediction formulas obtained.

[0043] The preset rock uniaxial compressive strength prediction formulas include the formula shown in Table 1: Table 1 Five empirical formulas were collected to form Formula List A, covering the intensity-velocity relationship of different lithologies.

[0044] S520, substitute the P-wave velocity in the P-wave velocity profile into the uniaxial compressive strength prediction formula of each rock in A to obtain the prediction result list B corresponding to A = (B1, B2, ..., B i ,…,B n ); Among them, B i A i The corresponding prediction results.

[0045] Substitute the longitudinal wave velocity into all the formulas in A to obtain the prediction result list B.

[0046] S530: Determine the rock uniaxial compressive strength prediction formula corresponding to the prediction result in B that has the greatest similarity to the indoor test result as the target rock uniaxial compressive strength prediction formula corresponding to the target area.

[0047] Compare the result in B with the Rc measured by indoor core tests and select the formula with the smallest error (e.g., error < 5%) as the target formula. For example, for a certain granite formation, Rc = 0.003Vp² is determined to be the optimal formula through comparison.

[0048] S540: Calculate the uniaxial compressive strength of the rock using a target rock uniaxial compressive strength prediction formula.

[0049] According to the obtained longitudinal wave velocity, five prediction formulas in Table 1 are used to obtain calculation results of five different prediction formulas. The uniaxial compressive strength obtained by calculation is close to the uniaxial compressive strength obtained by the indoor test results and can be used as the prediction formula for the saturated uniaxial compressive strength of the rock in this project, thereby calculating the integrity coefficient contour map.

[0050] Avoid the limitations of a single formula and achieve precise lithology-formula matching through data comparison, greatly reducing prediction errors compared to fixed formulas. Reduce the amount of testing, as only a small amount of core testing is needed to determine the applicable formula, saving 70% of indoor testing costs and time compared to traditional full-sample testing.

[0051] S600 generates a BQ contour map based on the rock integrity index and the uniaxial compressive strength of the rock, and determines the surrounding rock grade through the BQ contour map.

[0052] Calculate the rock integrity index, combine Rc and correction coefficient to generate BQ contour map, and compare with the standard to determine the surrounding rock grade, such as Grade I to Grade V.

[0053] Furthermore, step S600 may include the following steps: S610, obtain the rock elastic longitudinal wave velocity V through in-hole acoustic logging pm And the rock elastic longitudinal wave velocity V is obtained through indoor tests pr .

[0054] S620, according to V pm and V pr , determine the rock mass integrity index K v =(V pm / V pr ) 2 .

[0055] S630, according to K v , determine the generation of BQ contour map; where the [BQ] value conforms to the following relationship: [BQ]=(100+3R c +250K v )-100(K1+K2+K3); Among them, R c is the uniaxial compressive strength of rock, K1, K2 and K3 are the correction coefficients for the influence of groundwater, main structural surface occurrence and initial stress state, respectively, which are obtained through field mapping, investigation and indoor tests.

[0056] According to the Engineering Rock Mass Classification Standard (GB / T50218-2014), the calculation formula of [BQ] value is: [BQ]=BQ-100(K1+K2+K3)=(100+3Rc+250Kv)-100(K1+K2+K3), where Rc is the saturated uniaxial compressive strength of rock, which can be obtained by indoor tests; K v is the rock mass integrity index, and the quantitative calculation method is K v =(V pm / V pr ) 2 ,V pmis the elastic longitudinal wave velocity of the rock mass, usually obtained through in-hole acoustic logging, V pr The rock elastic longitudinal wave velocity is obtained through indoor experiments; K1, K2 and K3 are the correction coefficients for the influence of groundwater, main structural surface attitude and initial stress state, respectively, and are obtained through field mapping, investigation and indoor experiments.

[0057] The method of this embodiment utilizes active surface waves and micro-motion detection to conduct surface wave exploration by arranging ground survey lines, eliminating the need for drilling or excavation. This is a non-destructive test, and elastic wave tomography testing can be performed with a small number of drill holes. Therefore, active surface waves, micro-motion detection, and elastic wave tomography testing can effectively reduce the number of drill holes required, effectively addressing issues such as large terrain elevation differences and dense vegetation at the survey site, which makes drilling difficult. This reduces the impact of road construction during drilling rig relocation, land occupation during construction, and mud discharge on the site, which damages vegetation. The reduced drilling workload also reduces the use of construction materials such as oil, water, and mud during drilling, reducing construction land occupation and saving energy, materials, water, and land. Furthermore, the use of active surface waves and micro-motion detection to generate BQ contour maps of the rock mass index and to categorize surrounding rock grades can identify continuous changes in tunnel surrounding rock, significantly reducing drilling workload, thereby lowering construction costs and effectively improving the quality and efficiency of surrounding rock grade determination.

[0058] Furthermore, although the steps of the method of the present disclosure are described in a particular order in the accompanying drawings, this does not require or imply that the steps must be performed in this particular order, or that all steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

[0059] An embodiment of the present invention also provides a non-transitory computer-readable storage medium, which can be set in an electronic device to store at least one instruction or at least one program related to implementing a method in a method embodiment. The at least one instruction or the at least one program is loaded and executed by the processor to implement the method provided in the above embodiment.

[0060] The program product may utilize any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0061] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries 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 thereof. A readable signal medium may also be any readable medium other than a readable storage medium that can transmit, propagate, or transfer a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0062] The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0063] The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including object-oriented programming languages such as Java, C++, etc., and conventional procedural programming languages such as "C" or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0064] An embodiment of the present invention further provides an electronic device including a processor and the aforementioned non-transitory computer-readable storage medium.

[0065] The electronic device is merely an example and should not limit the functions and scope of use of the embodiments of the present application.

[0066] The electronic device is implemented as a general-purpose computing device. Components of the electronic device may include, but are not limited to, the aforementioned at least one processor, the aforementioned at least one memory, and a bus connecting different system components (including the memory and the processor).

[0067] The memory stores program codes, which can be executed by the processor, so that the processor performs the steps of various embodiments described in this specification.

[0068] The memory may include readable media in the form of volatile memory, such as random access memory (RAM) and / or cache memory, and may further include read-only memory (ROM).

[0069] The memory may also include a program / utility having a set (at least one) of program modules, such program modules including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0070] The bus may represent one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, or a local bus using any of a variety of bus architectures.

[0071] The electronic device may also communicate with one or more external devices (e.g., keyboards, pointing devices, Bluetooth devices, etc.), one or more devices that enable a user to interact with the electronic device, and / or any device that enables the electronic device to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface. Furthermore, the electronic device may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter. The network adapter communicates with other modules of the electronic device via a bus. It should be understood that, although not shown in the figures, other hardware and / or software modules may be used in conjunction with the electronic device, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0072] Through the description of the above embodiments, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the embodiments of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the embodiments of the present disclosure.

[0073] An embodiment of the present invention further provides a computer program product comprising program code. When the program product is run on an electronic device, the program code is used to enable the electronic device to execute the steps of the method according to various exemplary embodiments of the present invention described above in this specification.

[0074] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should also be understood by those skilled in the art that various modifications may be made to the embodiments without departing from the scope and spirit of the present invention.

Claims

1. A method for determining the surrounding rock grade of underground engineering based on surface wave exploration, characterized in that: The method comprises the following steps: S100, using an active surface wave method to obtain a first Rayleigh wave velocity VR1 corresponding to the target area; and using a micro-surface wave method to obtain a second Rayleigh wave velocity VR2 corresponding to the target area; wherein VR1 reflects the rock mass characteristics within a first depth range within the target area, and VR2 reflects the rock mass characteristics within a second depth range within the target area; the end depth of the first depth range is the starting depth of the second depth range; S200, obtains the Poisson's ratio, P-wave velocity, and S-wave velocity of each lithology through borehole velocity testing, and then converts VR1 and VR2 into S-wave velocity; S300, splicing the shear wave velocity data corresponding to VR1 and the shear wave velocity data corresponding to VR2 to obtain a continuous shear wave velocity profile; S400, converting the shear wave velocity profile to obtain a longitudinal wave velocity profile; S500, calculates the uniaxial compressive strength of rock based on the P-wave velocity in the P-wave velocity profile; S600 generates a BQ contour map based on the rock integrity index and the uniaxial compressive strength of the rock, and determines the surrounding rock grade through the BQ contour map.

2. The method for determining the surrounding rock grade of underground engineering based on surface wave exploration according to claim 1, characterized in that: Step S100 includes the following steps: S110, surveying the target area, and based on the survey results, arranging ground survey lines, determining observation points and array parameters for active surface waves and micro-seismic surface waves; S120, marking the locations of the geophones and the exciting points on the survey line; S130 uses the active surface wave method to generate Rayleigh waves through excitation, and uses a detector to collect the dispersion curve to obtain VR1; S140 uses the micro-surface wave method to observe natural vibration signals through the array and obtain the Rayleigh wave phase velocity dispersion curve to obtain VR2.

3. The method for determining the grade of surrounding rock of underground engineering based on surface wave exploration according to claim 1, characterized in that: Step S200 includes the following steps: S210, obtain the longitudinal wave velocity V of the target lithologic rock mass through borehole wave velocity testing p and shear wave velocity V s ; Wherein, target lithology is any lithology; S220, according to V p and V s , determine the Poisson's ratio of the target lithology rock mass ; S230, according to μ d , convert VR1 and VR2 into shear wave velocities ; Where VR is the Rayleigh wave velocity corresponding to VR1 or VR2 in the velocity profile; η S is the conversion factor between Rayleigh wave and shear wave velocity; .

4. The method for determining the grade of surrounding rock of underground engineering based on surface wave exploration according to claim 1, characterized in that: Step S500 includes the following steps: S510, obtaining each preset rock uniaxial compressive strength prediction formula to obtain a rock uniaxial compressive strength prediction formula list A=(A1, A2, ..., A i ,…,A n ), i=1, 2,...,n; among them, A i is the i-th preset rock uniaxial compressive strength prediction formula obtained, and n is the number of preset rock uniaxial compressive strength prediction formulas obtained; S520, substitute the P-wave velocity in the P-wave velocity profile into the uniaxial compressive strength prediction formula of each rock in A to obtain the prediction result list B corresponding to A = (B1, B2, ..., B i ,…,B n ); Among them, B i A i The corresponding prediction results; S530, determining the rock uniaxial compressive strength prediction formula corresponding to the prediction result in B that has the greatest similarity to the indoor test result as the target rock uniaxial compressive strength prediction formula corresponding to the target area; S540: Calculate the uniaxial compressive strength of the rock using a target rock uniaxial compressive strength prediction formula.

5. The method for determining the grade of surrounding rock of underground engineering based on surface wave exploration according to claim 1, characterized in that: Step S600 includes the following steps: S610, obtain the rock elastic longitudinal wave velocity V through in-hole acoustic logging pm And the rock elastic longitudinal wave velocity V is obtained through indoor tests pr ; S620, according to V pm and V pr , determine the rock mass integrity index K v =(V pm / V pr ) 2 ; S630, according to K v , determine the generation of BQ contour map; where the [BQ] value conforms to the following relationship: <h2 style=";text-align:left;direction:ltr">[BQ]=(100+3R)<h2 style=";text-align:left;direction:ltr"> c <h2 style=";text-align:left;direction:ltr"> +250K<h2 style=";text-align:left;direction:ltr"> v <h2 style=";text-align:left;direction:ltr"> (-100) (K1+K2+K3) Among them, R c is the uniaxial compressive strength of rock, K1, K2 and K3 are the correction coefficients for the influence of groundwater, main structural surface occurrence and initial stress state, respectively, which are obtained through field mapping, investigation and indoor tests.

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