Rock mass integrity quantitative analysis method based on micro-motion spectrum ratio method

Abstract

The invention discloses a rock mass integrity quantitative analysis method based on a micro-motion spectrum ratio method. The rock mass integrity quantitative analysis method comprises the following steps: acquiring a micro-motion signal of an exploration area and longitudinal wave velocity data at a drill hole of the exploration area; processing the micro-motion signal to obtain a transverse wave velocity profile of the exploration area; determining transverse wave velocity data at the drilling position based on the transverse wave velocity profile, and determining dynamic Poisson's ratio data at the drilling position based on the transverse wave velocity data and the longitudinal wave velocity data at the drilling position; determining a mapping relation function of the transverse wave velocity data and the dynamic Poisson's ratio data at the drilling position, and determining the dynamic Poisson's ratio data of the exploration area based on the mapping relation function; determining the longitudinal wave velocity and the integrity index of the exploration area based on the transverse wave velocity profile and the dynamic Poisson's ratio data of the exploration area; and performing BQ-method surrounding rock grading based on the longitudinal wave velocity and the integrity index of the exploration area. The rock mass integrity quantitative analysis can be effectively carried out, the construction period can be shortened, the efficiency is improved, the cost is saved, and the safety is improved.

Description

Technical Field

[0001] The present invention relates to the field of exploration technology, and in particular to a method, device, equipment and medium for quantitatively analyzing rock mass integrity based on a micro-motion spectrum ratio method. Background Art

[0002] The deep buried tunnels of long-distance oil and gas pipelines and underground water-sealed caverns and tunnels are complex and diverse in geological units, so a series of methodological and technical difficulties will be encountered during the survey, design and construction process. Adverse geological phenomena such as broken surrounding rocks, karst caves, and fractured zones near the tunnel body will pose safety hazards to tunnel construction. The analysis and evaluation of the integrity of the surrounding rock of such tunnels is a key link in tunnel design and construction. It has obvious social and economic benefits in guiding the design of tunnel excavation and support schemes, reducing construction risks, avoiding engineering accidents, and protecting the safety of life and property.

[0003] At present, the surrounding rock classification evaluation of deep buried tunnels and underground water-sealed caverns is mostly based on elastic wave values. However, due to the limitation of seismic exploration sources, the effective exploration depth of hammer sources is generally about 60m, and the effective exploration depth of drop weight (impact) sources is generally about 100m. The source vehicle is affected by the terrain and is difficult to be used in deep buried tunnels and underground water-sealed caverns. If effective seismic exploration is achieved below a burial depth of 200m, it is generally necessary to use explosive sources or new technology gas explosion sources in recent years. Explosive sources are difficult to approve and require source holes. On-site blasting operations require specific personnel to hold certificates to work, and the working time is limited. There are safety and efficiency issues, and the cost is high. The commonly used shallow earthquake sources are as follows:

[0004] Table 1 Comparison of advantages and disadvantages of common shallow earthquake sources

[0005]

[0006]

[0007] During the survey and design stage, the quantification of the surrounding rock integrity of deep-buried tunnels and underground water-sealed caverns is mainly based on the qualitative description of geological surveys, and a comprehensive hierarchical evaluation method combining the core drilling test method and the rock mass longitudinal wave velocity method. Among them, the geological survey method is to investigate the lithology, rock formation occurrence and regional geological structure of the proposed site through near-surface geological mapping, and make a macroscopic judgment on the surrounding rock integrity of deep-buried tunnels and underground water-sealed caverns. The core drilling test method is the most reliable and intuitive method to judge the surrounding rock integrity of deep-buried tunnels and underground water-sealed caverns. However, in reality, due to the limitations of the number of boreholes, terrain and environmental conditions, and survey costs, there is a problem of using points to represent the whole, and it is difficult to truly reflect the true geological conditions of the tunnel axis or the underground water-sealed cavern axis. The rock mass longitudinal wave velocity method is an indirect quantitative evaluation method, which is generally obtained through seismic refraction wave exploration. The state's control over flammable and explosive materials limits the application of the elastic wave method to the quantitative evaluation of the surrounding rock integrity of deep-buried tunnels and underground water-sealed caverns.

[0008] The micro-motion spectrum ratio method, with the help of the constant micro-motion energy in nature, adopts a scientific and reasonable array arrangement method and advanced spectrum analysis technology. It is light and efficient, not limited by the earthquake source, has low requirements for site conditions, has high-precision bedrock surface resolution, and can achieve controllable exploration depth through changes in the array size. However, in actual work, the problem with the micro-motion spectrum ratio method is that the inversion obtains the apparent velocity value of the surface wave, which can realize qualitative analysis but cannot be quantitatively analyzed and evaluated. In short, it cannot classify the surrounding rock grades.

[0009] At present, the micromotion spectrum ratio method is widely used in urban engineering geophysical exploration, such as the detection of subway boulders in "Two-dimensional micromotion profile detection of "boulders" - taking Shenzhen Metro Line 7 as an example (Xu Peifen et al., 2012)", karst cave detection in "Application of micromotion technology in karst exploration of Dalian subway (Li Naibin et al., 2019)", and bedrock undulation interface detection in "Application of micromotion detection method in urban engineering geological exploration (Zhuo Qiliang et al., 2020)", etc. However, it is still in the exploratory stage in the exploration of deep buried tunnels and underground water-sealed caverns of long-distance oil and gas pipelines. Therefore, it is necessary to provide a new idea and method based on the micromotion spectrum ratio method for the quantitative analysis and evaluation of the surrounding rock integrity of deep buried tunnels and underground water-sealed caverns. Summary of the invention

[0010] The main purpose of the present invention is to provide a method, device, equipment and medium for quantitative analysis of rock integrity based on the micro-vibration spectrum ratio method, so as to solve the problems of limited operation, low efficiency, great safety hazards and / or high cost when using electromagnetic method and shallow seismic method for quantitative evaluation of surrounding rock integrity in the prior art.

[0011] According to one aspect of the present invention, a method for quantitatively analyzing rock mass integrity based on a micro-motion spectrum ratio method is proposed, comprising:

[0012] Acquire micro-vibration signals in the exploration area and P-wave velocity data at the borehole in the exploration area, wherein the P-wave velocity data at the borehole is obtained by sonic logging;

[0013] Process the micro-motion signal to obtain the shear wave velocity profile of the exploration area;

[0014] Determine shear wave velocity data at the borehole based on the shear wave velocity profile, and determine dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole;

[0015] Determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function;

[0016] Determine the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area;

[0017] The BQ method surrounding rock grade classification is carried out based on the longitudinal wave velocity and integrity index of the exploration area.

[0018] According to one embodiment of the present invention, the micro-motion signal is acquired via a micro-motion detection device, which adopts a regular hexagonal array with an array radius of 30 m.

[0019] According to an embodiment of the present invention, processing the micro-motion signal includes: obtaining a dispersion curve by a spatial autocorrelation method and / or a frequency-wavenumber method and inverting the dispersion curve.

[0020] According to one embodiment of the present invention, the shear wave velocity data and the longitudinal wave velocity data at the borehole are obtained by fitting the shear wave velocity and the longitudinal wave velocity with the depth curves respectively obtained by fitting the following formulas:

[0021] f(x)=a 0 +a 1 x+a 2 x 2 +…+a n x n

[0022] Where x is the depth, f(x) is the shear wave velocity or longitudinal wave velocity at the borehole, and a 0 to a n is the coefficient.

[0023] According to one embodiment of the present invention, the dynamic Poisson's ratio data at the borehole is calculated according to the following formula:

[0024]

[0025] Where μ is the dynamic Poisson’s ratio at the borehole; v p is the longitudinal wave velocity at the borehole; vs is the shear wave velocity at the borehole.

[0026] According to one embodiment of the present invention, determining the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function includes: determining the dynamic Poisson's ratio data of the exploration area according to the following formula:

[0027]

[0028] Among them, μ pm is the dynamic Poisson's ratio of the exploration area; c 0 is the coefficient; f(v s ) is the mapping relationship function.

[0029] According to one embodiment of the present invention, the longitudinal wave velocity and the integrity index of the exploration area are calculated according to the following formula:

[0030]

[0031]

[0032] Among them, v pm is the longitudinal wave velocity in the exploration area; μ pm is the dynamic Poisson's ratio of the exploration area; v sm is the shear wave velocity of the exploration area determined based on the shear wave velocity profile; k d is the integrity index; v pr is the rock wave velocity.

[0033] According to another aspect of the present invention, a device for quantitatively analyzing rock mass integrity based on a micro-vibration spectrum ratio method is provided, comprising:

[0034] An acquisition module is configured to acquire micro-vibration signals in the exploration area and longitudinal wave velocity data at the borehole in the exploration area, wherein the longitudinal wave velocity data at the borehole is obtained by acoustic logging;

[0035] A micro-motion signal processing module configured to process the micro-motion signal to obtain a shear wave velocity profile of the exploration area;

[0036] A first determination module is configured to determine shear wave velocity data at the borehole based on the shear wave velocity profile, and determine dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole;

[0037] A second determination module is configured to determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function;

[0038] A third determination module is configured to determine the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area;

[0039] The grading module is configured to perform BQ method surrounding rock grading based on the longitudinal wave velocity and integrity index of the exploration area.

[0040] According to another aspect of the present invention, a computer device is provided, comprising:

[0041] at least one processor; and

[0042] The memory stores a computer program that can be run on the processor, and when the processor executes the program, the method described in any of the above embodiments is implemented.

[0043] According to another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method described in any of the above embodiments is implemented.

[0044] In the technical solution of the present invention, the micro-motion signals in the exploration area and the longitudinal wave velocity data at the borehole are used as the data basis, and the dynamic Poisson's ratio is used for conversion to calculate the longitudinal wave velocity and integrity index of the exploration area. After that, the BQ method surrounding rock grade classification can be performed based on the longitudinal wave velocity and the integrity index. The present invention performs quantitative analysis of rock integrity based on the micro-motion spectrum ratio method, which can shorten the construction period, improve efficiency, save costs and improve safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0046] Figure 1 A flow chart showing a method for quantitatively analyzing rock mass integrity according to an embodiment of the present invention;

[0047] Figure 2(a) to Figure 2(c) A comparison diagram of spectrum of different arrays according to an embodiment of the present invention is shown;

[0048] Figure 3 The schematic diagram of the micro-motion array layout is shown;

[0049] Figure 4 A schematic diagram of a regular hexagonal micro-motion array according to an embodiment of the present invention is shown;

[0050] Figure 5 A micromotion detection inversion result diagram according to an embodiment of the present invention is shown;

[0051] Figure 6A diagram showing the geological interpretation results of micro-seismic detection according to an embodiment of the present invention is shown;

[0052] Figure 7 A result diagram showing the comparison of longitudinal and transverse wave velocities and dynamic Poisson's ratio at a borehole according to an embodiment of the present invention is shown;

[0053] Figure 8 A distribution diagram of dynamic Poisson's ratio values ​​of the entire measuring line according to an embodiment of the present invention is shown;

[0054] Fig. 9 A result diagram of the longitudinal wave velocity of the entire survey line according to an embodiment of the present invention is shown;

[0055] Fig.10 A schematic diagram of a rock mass integrity quantitative analysis device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0056] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0057] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0058] refer to Figure 1 The present invention proposes a method for quantitative analysis of rock mass integrity based on micro-vibration spectrum ratio method, comprising:

[0059] Acquire micro-vibration signals in the exploration area and P-wave velocity data at the borehole in the exploration area, wherein the P-wave velocity data at the borehole is obtained by sonic logging;

[0060] Process the micro-motion signal to obtain the shear wave velocity profile of the exploration area;

[0061] Determine shear wave velocity data at the borehole based on the shear wave velocity profile, and determine dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole;

[0062] Determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function;

[0063] Determine the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area;

[0064] The BQ method surrounding rock grade classification is carried out based on the longitudinal wave velocity and integrity index of the exploration area.

[0065] In an embodiment of the present invention, the micro-motion signal of the exploration area and the longitudinal wave velocity data at the borehole are used as the data basis, and the dynamic Poisson's ratio is used for conversion to calculate the longitudinal wave velocity and integrity index of the exploration area. After that, the BQ method surrounding rock grade classification can be performed based on the longitudinal wave velocity and the integrity index. The present invention performs quantitative analysis of rock integrity based on the micro-motion spectrum ratio method, which can shorten the construction period, improve efficiency, save costs and improve safety.

[0066] Micro-seismic detection is usually performed along a predetermined survey line. The exploration area of ​​the present invention may represent the area where the survey line is located. The "S-wave velocity profile of the exploration area" may represent the distribution of the S-wave velocity in the exploration area in the depth direction and the survey line direction. For example, Figure 5 In the shear wave velocity profile, the horizontal axis is the mileage along the survey line, the vertical axis is the elevation along the depth direction, and the color indicates the shear wave velocity. Based on the shear wave velocity profile, the shear wave velocity at a specific position in the depth direction and the survey line direction can be obtained. The shear wave velocity in the shear wave velocity profile is obtained by inversion and is also called "apparent shear wave velocity" to distinguish it from the shear wave velocity obtained by actual detection.

[0067] In some embodiments, micro-motion signals are obtained through a micro-motion detection device, which uses a regular hexagonal array with an array radius of 30m. The use of a regular hexagonal array can obtain better signal quality and higher production efficiency. When the array radius is 30m, the effective exploration depth can reach 350m, which can meet the exploration depth requirements of deep buried tunnels of long-distance oil and gas pipelines and underground water-sealed caverns, tunnels and caverns.

[0068] In some embodiments, processing the micro-motion signal includes: obtaining a dispersion curve by a spatial autocorrelation method and / or a frequency-wavenumber method and inverting the dispersion curve.

[0069] In some embodiments, the shear wave velocity data and the longitudinal wave velocity data at the borehole are obtained by fitting the shear wave velocity and the longitudinal wave velocity with depth curves respectively obtained by fitting the following formulas:

[0070] f(x)=a 0 +a 1 x+a 2 x 2 +…+a n x n

[0071] Where x is the depth, f(x) is the shear wave velocity or longitudinal wave velocity at the borehole, and a 0 to a n are coefficients determined by fitting.

[0072] In some embodiments, the dynamic Poisson's ratio data at the borehole is calculated according to the following formula:

[0073]

[0074] Where μ is the dynamic Poisson’s ratio at the borehole; v p is the longitudinal wave velocity at the borehole; v s is the shear wave velocity at the borehole. Based on the shear wave velocity and longitudinal wave velocity at the borehole varying with depth curves and the formula, the dynamic Poisson's ratio varying with depth curve at the borehole can be calculated, and the dynamic Poisson's ratio varying with depth curve can be further smoothed and filtered.

[0075] In some embodiments, determining the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function includes: determining the dynamic Poisson's ratio data of the exploration area according to the following formula:

[0076]

[0077] Among them, μ pm is the dynamic Poisson's ratio of the exploration area; c 0 is a coefficient, and its specific value can be determined according to actual conditions and / or experience; f(v s ) is the mapping relationship function.

[0078] In some embodiments, the P-wave velocity and the integrity index of the survey area are calculated according to the following formula:

[0079]

[0080]

[0081] Among them, v pm is the longitudinal wave velocity in the exploration area; μ pm is the dynamic Poisson's ratio of the exploration area; v sm is the shear wave velocity of the exploration area determined based on the shear wave velocity profile; k d is the integrity index; v pr is the rock wave velocity, which can be measured by corresponding detection means.

[0082] In some embodiments, the present invention provides a method for grading surrounding rocks of tunnels and underground caverns by using natural field source micro-vibration signals, comprising the following steps:

[0083] Step 1: Determine the optimal array arrangement suitable for the micro-motion spectrum ratio method in geophysical exploration of deep buried tunnels and underground water-sealed caverns - the regular hexagonal (circular) array.

[0084] Two experiments were conducted in a national reserve project: the relationship between array diameter and effective exploration depth, and the relationship between array layout and exploration efficiency and data quality. Triangular nesting, regular hexagonal and linear array layout verification tests were carried out on site, as well as observation tests with array radii of 10m, 20m and 30m. The field test results are as follows: Figure 2(a) to Figure 2(c) As shown, Figure 2(a) to Figure 2(c) The test results of the triangular nested array, regular hexagonal array, and linear array are shown in turn. According to the field test results, the energy of the dispersion spectrum of the micro-seismic data collected by the triangular nested and regular hexagonal arrays is clear, with good focusing, continuity, and consistency. The energy ridge is narrow in the high-frequency range, and the phase velocity has a high resolution, which is conducive to the picking of dispersion curves; the energy continuity of the dispersion spectrum of the micro-seismic data obtained by the linear array is poor, and there is an obvious step-jump phenomenon, which easily causes inaccurate calculation of the dispersion curve. When collecting data in the field, the triangular nested array needs to arrange 5 parallel survey lines along the axis to place the seismic pickup, and the work efficiency is low, while the regular hexagonal array only needs to arrange 3 survey lines. It can be seen that the regular hexagonal (circular array) array has higher production efficiency than the triangular nested array under the premise of obtaining the same data quality. When the radius is 30m, the effective exploration depth can reach 350m, which can meet the exploration depth requirements of deep buried tunnels of long-distance oil and gas pipelines and underground water-sealed caverns, tunnels, and caverns.

[0085] Step 2: Process the natural field source micro-motion signal and extract the dispersion curve and inversion through the spatial autocorrelation method (SPAC) and frequency-wavenumber method (FK).

[0086] The specific processing flow is: obtain any frequency f from the micro-motion signal record 0 The spatial autocorrelation coefficient ρ 0 , fitting the first kind of zero-order Bessel function, and calculating the phase velocity c(f 0 ). Through the above steps, the fc frequency dispersion point of the entire micro-seismic data can be obtained. After smoothing, the dispersion curve can be obtained. According to the curve variation law and constraint conditions, a qualitative explanation is given to determine the initial geological model. The theoretical dispersion curve is obtained through forward calculation, and then the fitting coefficient is calculated. The inversion result is obtained according to the fitting degree, and finally the apparent shear wave velocity profile is obtained.

[0087] Step 3: Based on the apparent shear wave velocity profile and the in-hole acoustic logging data, calculate the dynamic Poisson's ratio curve of the formation lithology at the borehole, and establish a mapping function between the dynamic Poisson's ratio and the shear wave velocity curve based on the formation dynamic Poisson's ratio curve at the borehole and the shear wave velocity curve, and then convert and obtain the dynamic Poisson's ratio value on the entire survey line. The specific steps are as follows:

[0088] First, the apparent shear wave velocity value v at the borehole is obtained by using the micro-vibration detection results and acoustic logging datas and the longitudinal wave velocity v p , press the formula to v s 、v p Perform curve fitting:

[0089] f(x)=a 0 +a 1 x+a 2 x 2 +…+nx n

[0090] Where: n is the number of discrete data points, a 0 …a n are the polynomial coefficients.

[0091] Thus, two v curves that change with depth at the borehole can be obtained. s 、v p Curve, where the acoustic logging curve v P The missing data can be filled by spline interpolation, so that v s 、v p The curves correspond one to one in depth, and then the following formula is used to obtain the dynamic Poisson's ratio value at each depth in the borehole.

[0092]

[0093] Where: μ is the dynamic Poisson's ratio, v p ——Longitudinal wave velocity, v s ——Transverse wave velocity.

[0094] The dynamic Poisson's ratio value obtained at this time is the value of each depth at the borehole. The dynamic Poisson's ratio value at the borehole is curve-fitted using the smoothing filter method. The mapping relationship function between the dynamic Poisson's ratio and the shear wave velocity curve at the borehole is established, and then the dynamic Poisson's ratio value on the profile (the entire survey line) is converted based on the following formula:

[0095]

[0096] Where: μ pm ——Dynamic Poisson’s ratio on the section, c 0 ——coefficient, f(v s )——mapping relationship function.

[0097] Step 4: Based on the apparent shear wave velocity and dynamic Poisson's ratio obtained by inverting the natural field source micro-vibration signal, the longitudinal wave velocity value v on the entire profile is calculated using the formula pm and the completeness index k d , the formula is:

[0098]

[0099]

[0100] Where: μ pm ——dynamic Poisson’s ratio on the section, v pm ——L-wave velocity on the profile, v sm ——The shear wave velocity of the micromotion result, v pr ——rock wave velocity, k d ——Integrity index.

[0101] Step 5: Use the calculated longitudinal wave velocity v pm and integrity factor k d , and the BQ method surrounding rock grade classification is carried out. P-wave velocity and integrity coefficient are important parameters for surrounding rock grade classification using the national standard BQ scoring method. This method can provide basic data for quantitative analysis and evaluation of the surrounding rock integrity of underground water-sealed caverns.

[0102] Combine the following Figures 3 to 9 And specific embodiments describe the technical solution of the present invention in detail.

[0103] 1. Optimal array arrangement: regular hexagonal array

[0104] The layout of deep buried tunnel arrays is studied. Currently, the commonly used array layouts include triangle nesting, circular array, cross array, L-shaped array and linear array, such as Figure 3 As shown, the size of various arrays and the number of detectors used in the array are directly related to the quality of the final analysis results.

[0105] According to the test results, the dispersion curves of the linear array in different directions are quite different, and the energy of the dispersion spectrum is relatively dispersed. Since it can only receive micro-seismic signals from one direction, it cannot fully reflect the real situation underground. The energy concentration of the dispersion spectrum of the triangular nesting and regular hexagonal arrangement is high, and the detection depth is large. They are more suitable for micro-seismic surveys of deep buried tunnels of long-distance oil and gas pipelines and underground water-sealed caverns. Among them, the triangular nesting array is not suitable for the layout principle of rugged mountainous areas, and the efficiency of field surveys is relatively low. Therefore, the most universal and optimal array layout is the regular hexagonal array (such as Figure 4 shown).

[0106] 2. Quantitative analysis and evaluation of surrounding rock of a certain reservoir using the micro-vibration spectrum ratio method

[0107] In this survey, a micro-seismic survey line was arranged in the reservoir area. The survey line area is about 1720m, the point spacing is 10-20m, and there are 82 points in total. The effective depth that can be detected is about 350m. The shear wave velocity of the entire field is mainly distributed in the range of 400-3000m / s. The micro-seismic detection inversion results are as follows Figure 5 shown.

[0108] Figure 5 In the vertical direction, the whole presents a "layered" distribution of upper and lower layers, and is partially agglomerated. The shear wave velocity of the upper part is mainly concentrated in 800-1300m / s, and the shear wave velocity of the lower part is mainly concentrated in 1300-3000m / s. The shear wave velocity of the gravel soil layer is 400-800m / s, which is mainly distributed in the 0.5m surface of the site and the surface of the river channel; the shear wave velocity of the interlayer of mud shale, marl and thin-layered limestone is 900-1500m / s, which is mainly distributed within the depth of 130m; the shear wave velocity of thick-layered and super-thick-layered bioclastic limestone is 1600-3200m / s, which is mainly distributed below 130m in depth, and a small part is distributed in the shallow part, and it mostly appears in agglomerates in the shear wave velocity contour map.

[0109] In the horizontal direction, the shear wave velocity contour lines have poor lateral continuity within the depth range of 130m, and are mostly "lumpy" or "interlayered" or "serrated". Combined with the geological conditions of the site, it is inferred that it is caused by the interlayer of mud shale, marl and thin-layered limestone. The boundary between high and low velocities is mostly the lithological boundary. Below the depth of 130m, the shear wave velocity contour lines have good continuity, but there are several obvious concave wave velocity contour lines in the river channel, showing a relatively low-velocity abnormal discontinuity. Combined with the geological survey and drilling data of the site, it is inferred that they are joint and fissure development areas. The specific interpretation is shown in Figure 6 .

[0110] The geophysical detection line passes through borehole ZK6, located at mileage K0+1160m. The longitudinal wave velocity of the acoustic logging at ZK6 and the shear wave velocity at K0+1160m are compared and analyzed. The part without longitudinal wave velocity is obtained by using the wave velocity of the reference rock sample and the numerical fitting method, so that the dynamic Poisson's ratio curve of the lithology at ZK6 can be obtained, as shown in the figure: Figure 7 As shown, Figure 7 In the left figure, the blue curve is the shear wave velocity curve, and the magenta curve is the longitudinal wave velocity curve.

[0111] The dynamic Poisson's ratio curve at ZK6 is between 0.1 and 0.44. Combined with the lithology of the mudstone, marlstone, and bioclastic limestone in the field, and referring to the rock test results and the empirical values ​​in the engineering geology manual, the calculated dynamic Poisson's ratio is within its range. Therefore, in this field, the dynamic Poisson's ratio of the entire survey line can be obtained by using the corresponding relationship between different shear wave velocities and dynamic Poisson's ratios and the micro-motion detection results, as shown below Figure 8 shown.

[0112] Finally, the shear wave velocity and dynamic Poisson's ratio values ​​measured by the micro-vibration detection results are converted using the formula to obtain the longitudinal wave velocity of the entire survey line, as follows Fig. 9As shown in the figure, the longitudinal wave velocity is mainly distributed in the range of 2000-4800 m / s. The longitudinal wave velocity result diagram is highly similar to the shear wave velocity diagram, and the high-speed and low-speed distribution positions are roughly the same. Therefore, it is feasible to convert the longitudinal wave velocity using the micro-motion detection results. The longitudinal wave velocity is an important parameter for the classification of surrounding rock grades in the BQ scoring method. This method can provide basic data for the quantitative analysis and evaluation of the surrounding rock integrity of underground water-sealed caverns.

[0113] Taking a 5 million cubic meter underground water-sealed cavern as an example, the comparative analysis of the exploration benefits of conventional shallow seismic reflection / refraction exploration and micro-seismic spectrum ratio method is as follows:

[0114] Table 2 Benefit comparison

[0115]

[0116]

[0117] Referring to Table 2, the micro-motion spectrum ratio method can save 27-45 days in project construction period compared with the conventional shallow seismic reflection / refraction method, and at least 500,000 yuan in on-site construction costs, which has not yet taken into account the compensation for young crops during the construction of the explosive source hole and the on-site idleness caused by the limited explosive source during major holidays. The use of the micro-motion spectrum ratio method for surrounding rock quantitative analysis and evaluation technology can fill the gap in unconventional engineering geophysical exploration methods for deep buried tunnels and caverns, accumulate new methods and experience for exploration technology, and save exploration costs. At the same time, because the micro-motion method is a passive source surface wave method and does not require a source, it removes the links such as the explosive source review and source hole construction, which greatly shortens the exploration period and meets the needs of improving quality and efficiency. The present invention has a wide range of applications and practical prospects, and can be used not only in the engineering survey of long-distance oil and gas pipelines, but also in the survey of underground caverns.

[0118] refer to Fig.10 The present invention also proposes a rock mass integrity quantitative analysis device 100 based on the micro-vibration spectrum ratio method, comprising:

[0119] An acquisition module 10 is configured to acquire micro-vibration signals in the exploration area and longitudinal wave velocity data at the borehole in the exploration area, wherein the longitudinal wave velocity data at the borehole is obtained by acoustic logging;

[0120] A micro-motion signal processing module 20 is configured to process the micro-motion signal to obtain a shear wave velocity profile of the exploration area;

[0121] A first determination module 30 is configured to determine shear wave velocity data at the borehole based on the shear wave velocity profile, and determine dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole;

[0122] A second determination module 40 is configured to determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function;

[0123] A third determination module 50 is configured to determine the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area;

[0124] The grading module 60 is configured to perform BQ method surrounding rock grading based on the longitudinal wave velocity and integrity index of the exploration area.

[0125] The present invention further proposes a computer device, comprising: at least one processor; and a memory, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, the method described in any of the above embodiments is implemented.

[0126] The present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method described in any of the above embodiments is implemented.

[0127] In summary, in view of the technical difficulties of the commonly used electromagnetic method and shallow seismic method in the geophysical exploration of deep buried tunnels and underground water-sealed caverns of long-distance oil and gas pipelines, the present invention first studies the arrangement of each detector in the micro-seismic array of the micro-seismic spectrum ratio method, the number of detectors in the array, the relationship between the array diameter and depth, and establishes the relationship between the array type, diameter and detectable effective depth; secondly, by analyzing and studying the micro-seismic wave velocity value and spectrum ratio, the unfavorable geological phenomena of deep buried tunnels and underground water-sealed caverns, such as the scale and actual location of unfavorable geological bodies such as karst, boulders, and low-speed broken zones, are analyzed and evaluated. Finally, combined with the results of borehole acoustic wave testing, with the help of the dynamic Poisson's ratio parameter, the purpose of quantitative analysis and evaluation of tunnel surrounding rock integrity by the micro-seismic method is achieved.

[0128] Based on the full use of the collected urban exploration results of the micro-motion method, combined with the exploration characteristics of deep buried tunnels of oil and gas pipelines and underground water-sealed caverns, this paper conducts a quantitative analysis of surrounding rock integrity based on the micro-motion spectrum ratio method. The specific technical research route is as follows:

[0129] 1) Study the linear relative relationship between the effective exploration depth of deep buried tunnels and underground water-sealed caverns and the diameter of the array using the micro-motion spectrum ratio method, and establish a corresponding relationship table between the array diameter and the effective exploration depth;

[0130] 2) Study the layout of deep tunnel arrays;

[0131] 3) Research on the data analysis and processing technology of the micro-motion spectrum ratio method. Different array layouts may collect micro-motion spectrum signals of different forms. After spectrum analysis and data analysis and processing, scientific and reliable micro-motion wave velocity values ​​and spectrum ratio parameters are obtained;

[0132] 4) According to the micro-motion velocity value of the micro-motion spectrum ratio method, combined with the longitudinal wave velocity obtained by the borehole acoustic logging test, the dynamic Poisson's ratio of the entire survey line is obtained. Finally, the longitudinal wave velocity of the entire survey line is obtained by converting the shear wave velocity and the dynamic Poisson's ratio values ​​measured by the micro-motion detection results using the formula, and the rock mass integrity index k of the micro-motion spectrum ratio method is calculated. d , the mature longitudinal wave velocity value is used to evaluate and analyze the integrity of the surrounding rock.

[0133] At present, the research results have been applied to a national reserve underground water-sealed cavern project. By comparing with the shallow seismic interpretation results arranged in the same field and the same survey line direction, the lateral and vertical resolutions of the micro-seismic interpretation results are significantly better than the conventional seismic results of explosive sources, and the results are highly consistent with the on-site geological survey results and drilling exposures. It has met the needs of long-distance oil and gas pipeline deep-buried tunnels and underground water-sealed cavern engineering surveys, and can provide guidance for tunnel design and construction.

[0134] It should be noted that a person skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0135] Furthermore, it should be appreciated that the computer-readable storage medium (eg, memory) herein may be either a volatile memory or a nonvolatile memory, or may include both volatile and nonvolatile memory.

[0136] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A quantitative analysis method for rock mass integrity based on micro-vibration spectrum ratio method, It is characterized in that include: Acquiring micro-vibration signals of an exploration area and P-wave velocity data at a borehole in the exploration area, wherein the P-wave velocity data at the borehole is obtained by acoustic logging; Processing the micro-motion signal to obtain a shear wave velocity profile of the exploration area; Determining shear wave velocity data at the borehole based on the shear wave velocity profile, and determining dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole; Determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function; Determining the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area; The surrounding rock grade classification is carried out by the BQ method based on the longitudinal wave velocity and integrity index of the exploration area.

2. The method according to claim 1, It is characterized in that The micro-motion signal is acquired via a micro-motion detection device, wherein the micro-motion detection device adopts a regular hexagonal array and the array radius is 30m.

3. The method according to claim 1, It is characterized in that The processing of the micro-motion signal includes: obtaining a dispersion curve by a spatial autocorrelation method and / or a frequency-wave number method and inverting the dispersion curve.

4. The method according to claim 1, It is characterized in that The shear wave velocity data and the longitudinal wave velocity data at the borehole are obtained by fitting the shear wave velocity and the longitudinal wave velocity with depth curves respectively according to the following formulas: f(x)=a 0 +a 1 x+a 2 x 2 +…+a n x n Where x is the depth, f(x) is the shear wave velocity or longitudinal wave velocity at the borehole, and a 0 to a n is the coefficient.

5. The method according to claim 1, It is characterized in that The dynamic Poisson's ratio data at the borehole is calculated according to the following formula: Where μ is the dynamic Poisson’s ratio at the borehole; v p is the longitudinal wave velocity at the borehole; v s is the shear wave velocity at the borehole.

6. The method according to claim 1, It is characterized in that The determining the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function includes: determining the dynamic Poisson's ratio data of the exploration area according to the following formula: Among them, μ pm is the dynamic Poisson's ratio of the exploration area; c 0 is the coefficient; f(v s ) is the mapping relationship function.

7. The method according to claim 1, It is characterized in that The P-wave velocity and integrity index of the survey area are calculated according to the following formula: Among them, v pm is the longitudinal wave velocity in the exploration area; μ pm is the dynamic Poisson's ratio of the exploration area; v sm k is the shear wave velocity of the exploration area determined based on the shear wave velocity profile; d is the integrity index; v pr is the rock wave velocity.

8. A quantitative analysis device for rock mass integrity based on micro-vibration spectrum ratio method, It is characterized in that include: An acquisition module is configured to acquire micro-vibration signals in an exploration area and longitudinal wave velocity data at a borehole in the exploration area, wherein the longitudinal wave velocity data at the borehole is obtained by acoustic logging; a micro-motion signal processing module, configured to process the micro-motion signal to obtain a shear wave velocity profile of the exploration area; a first determination module configured to determine shear wave velocity data at the borehole based on the shear wave velocity profile, and to determine dynamic Poisson's ratio data at the borehole based on the shear wave velocity data and the longitudinal wave velocity data at the borehole; A second determination module is configured to determine a mapping relationship function between the shear wave velocity data and the dynamic Poisson's ratio data at the borehole, and determine the dynamic Poisson's ratio data of the exploration area based on the mapping relationship function; A third determination module is configured to determine the P-wave velocity and integrity index of the exploration area based on the S-wave velocity profile and the dynamic Poisson's ratio data of the exploration area; The grading module is configured to perform BQ method surrounding rock grading based on the longitudinal wave velocity and integrity index of the exploration area.

9. A computer device, include: at least one processor; as well as A memory storing a computer program executable on the processor, wherein the processor implements the method according to any one of claims 1 to 7 when executing the program.

10. A computer-readable storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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