Deep cutting rock high slope unloading damage dynamic evaluation method

Abstract

The invention discloses a deep cutting rock high slope unloading damage dynamic evaluation method. The method comprises the following steps: determining an excavation range of a deep cutting rock high slope, determining physical and mechanical parameters of the deep cutting rock high slope, testing wave velocity values and deformation moduli at different positions of the high slope, and determining a reference wave velocity value when the deep cutting rock high slope is not damaged and a reference deformation modulus when the deep cutting rock high slope is not damaged; establishing a deep cutting rock high slope unloading area range determination model with coupling of an acoustic wave test and a drilling elastic modulus test; determining the range of the unloading damage area of the deep cutting rock high slope; calculating an unloading damage comprehensive evaluation coefficient value; and evaluating according to the calculated unloading damage comprehensive evaluation coefficient value of each coordinate point. According to the method, the single evaluation of the unloading damage of the deep cutting rock high slope in the past can be broken through, the unloading damage factors caused by engineering disturbance, rock mass degradation and environmental evolution are added, the evaluation system is more comprehensive, and quantitative evaluation of multi-factor coupling can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of hydropower engineering, and in particular relates to a dynamic evaluation method for unloading damage of a deep-cut rock high slope. Background Art

[0002] In hydropower projects, deep-cut rock slopes are different from conventional slopes and are a special type of high slope engineering. The slope shape is gradually formed by cutting the mountain slope and reducing the load, and excavating from top to bottom. Due to the deep excavation of the mountain, a huge rock face will be formed. This not only creates geometric conditions for the slope rock mass to become unstable, bringing stability problems to the high slope rock mass, but also such a large-scale high slope is excavated in a relatively short period of time, which causes the stress-strain balance system formed in the rock mass over a long period of time to be drastically broken, which will cause a series of rock unloading damage problems. Unloading damage of deep rock high slopes specifically refers to the phenomenon of deformation, cracking or loosening caused by the release of internal stress in deep high slopes due to engineering disturbances, rock mass degradation, and environmental evolution factors. Dynamic evaluation of unloading damage has become a difficult problem faced in current projects and is also a prerequisite for support design and construction.

[0003] In current design and construction, the evaluation of unloading damage in deep-cut rock high slopes is still in the qualitative and semi-quantitative stages, and the factors considered in the quantitative evaluation are too single. However, excavation unloading is affected by multiple factors with varying degrees of influence. At the same time, traditional methods cannot reflect the dynamic evolution of excavation damage, resulting in inaccurate damage evaluation results.

[0004] Therefore, it is particularly important to propose a dynamic evaluation method for unloading damage of deep-cut rock high slopes that can consider the influence of multiple factors. Summary of the Invention

[0005] Aiming at the problem that the current quantitative evaluation of unloading damage in deep-cut rock slopes is too single in terms of factors and cannot reflect the dynamic evolution of excavation damage, a dynamic evaluation method for unloading damage in deep-cut rock slopes is proposed, which can achieve quantitative evaluation of multiple factors coupling and has more scientific, reasonable and comprehensive evaluation results.

[0006] To achieve the above object, the present invention provides a method for dynamic evaluation of unloading damage of deep-cut rock high slopes, comprising the following steps:

[0007] 1) Conduct on-site surveys to determine the excavation scope of deep-cut rock slopes; determine the physical and mechanical parameters of deep-cut rock slopes based on field tests; test the wave velocity values ​​at different locations on the slopes based on acoustic wave tests; test the deformation modulus at different locations on the slopes based on borehole elastic modulus tests; and conduct indoor tests to determine the baseline wave velocity value S0 and the baseline deformation modulus E0 of undamaged deep-cut rock slopes.

[0008] 2) Based on the acoustic wave test and borehole elastic modulus test in step 1), a model for determining the range of the unloading zone of the deep-cut rock high slope is established by coupling the acoustic wave test and the borehole elastic modulus test;

[0009] 3) Determine the extent of the unloading damage area of ​​the deep-cut rock high slope based on the calculation results of the model for determining the extent of the unloading area of ​​the deep-cut rock high slope in step 2);

[0010] 4) Calculate the comprehensive evaluation coefficient of unloading damage for each coordinate point within the unloading damage area of ​​the deep-cut rock slope in step 3) based on the refined evaluation model of unloading damage;

[0011] 5) Evaluate based on the comprehensive evaluation coefficient of unloading damage at each coordinate point calculated in step 4).

[0012] Furthermore, in step 2), the model for determining the range of the unloading zone of the deep-cut rock high slope by coupling the acoustic wave test and the borehole elastic modulus test is as follows:

[0013] (Formula 1)

[0014] (Equation 2)

[0015]

[0016] Where, q refers to the demarcation coefficient of the unloading area, q （x,z） Refers to the circle coefficient at the (x, z) coordinate; γ （x,z） Refers to the model correction coefficient; α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of the deformation modulus test at the (x, z) coordinate; S0 refers to the reference wave velocity value when the deep rock high slope is not damaged, S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock slope is unloaded; E0 refers to the reference deformation modulus value when the deep rock slope is not damaged, E （x,z） It refers to the deformation modulus value at the (x, z) coordinate when the deep rock high slope is unloaded; a refers to the sensitivity coefficient of the acoustic wave test, and b refers to the sensitivity coefficient of the deformation modulus test.

[0017] Furthermore, in the step 2), the values ​​of the acoustic wave test sensitivity coefficient a and the deformation modulus test sensitivity coefficient b are determined according to the physical and mechanical parameters of the deep-cut rock high slope. When the ratio of the wave velocity test value at the point to the benchmark wave velocity value is greater than or equal to 0.8, a is taken as 1; when the ratio of the wave velocity test value at the point to the benchmark wave velocity value is less than 0.8, a is taken as 1.1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is greater than or equal to 0.8, b is taken as 1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is less than 0.8, b is taken as 1.1.

[0018] Furthermore, in step 2), the importance coefficient α of the acoustic wave test at the (x, z) coordinate is （x,z） and deformation modulus test importance coefficient β （x,z） The calculation formula is as follows:

[0019] (Formula 4)

[0020] (Formula 5)

[0021] in, (Equation 6)

[0022] (Equation 7)

[0023] Where, α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of deformation modulus test at (x, z) coordinate; S 归一化（x,z） Refers to the normalized acoustic wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; μ s Refers to the mean of all wave velocity values ​​of deep-cut rock high slope, σ s Refers to the standard deviation of all acoustic wave velocity values ​​on deep-cut rock slopes; S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; E 归一化（x,z） Refers to the normalized deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; E （x,z） Refers to the deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; μ d Refers to the mean value of all deformation modulus values ​​of deep rock high slope, σ d Refers to the standard deviation of all deformation modulus values ​​of deep rock high slopes.

[0024] Furthermore, in step 3), the range of the unloading damage area of ​​the deep-cut rock high slope is determined according to the calculation results of the deep-cut rock high slope unloading area range determination model in step 2), specifically as follows:

[0025] When the calculated q（x,z） When the value is greater than or equal to 0.18, the coordinate point is the unloading area; all coordinate points in the unloading area are determined as the range of the unloading damage area of ​​the deep rock high slope.

[0026] Furthermore, in step 4), the unloading damage refined evaluation model is as follows:

[0027] (Equation 8)

[0028] Where H （x,z） Refers to the comprehensive evaluation coefficient of unloading damage at the (x, z) coordinate; e refers to the natural constant; M and N refer to the comprehensive influence constant; δ g(x,z) Refers to the unloading damage strain caused by engineering disturbance factors at the (x, z) coordinate (obtained from on-site engineering disturbance strain test); δ y(x,z) Refers to the unloading damage strain caused by rock mass degradation factors at the (x, z) coordinate (obtained from on-site rock mass degradation strain testing); δ h(x,z) Refers to the unloading damage strain caused by environmental evolution factors at the (x, z) coordinate (obtained from the on-site environmental evolution strain test); δ j Refers to the unloading damage limit strain (obtained from the on-site ultimate tensile strain test); θ refers to the stress coefficient.

[0029] Furthermore, M is 1.0 or 1.1, and N is 1.0 or 1.1; when the impact of engineering disturbance, rock mass degradation, and environmental evolution is strong, M and N are both 1.1; when the impact of engineering disturbance, rock mass degradation, and environmental evolution is not strong, M and N are both 1.0.

[0030] Furthermore, in step 5), the values ​​of the comprehensive evaluation coefficient of unloading damage of each coordinate point calculated in step 4) are arranged from large to small to obtain data set K, and the coordinate point area corresponding to the first 40% of the sorting of data set K is defined as a strong unloading area, the coordinate point area corresponding to the middle 40% to 70% of the sorting of data set K is defined as a weak unloading area, and the coordinate point area corresponding to the last 30% of the sorting of data set K is defined as a micro unloading area.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The proposed model for determining the unloading zone of deep-cut rock high slopes by coupling the sonic wave test with the borehole elastic modulus test can preliminarily determine the unloading zone of deep-cut slopes. The refined evaluation model for unloading damage coupled with multiple factors based on engineering disturbance, rock mass degradation, and environmental evolution is established to calculate and realize a refined evaluation of the degree of unloading damage within the unloading zone. The evaluation results are made more scientific and reasonable by "preliminary delineation of the unloading zone - refined evaluation of the damage within the delineated unloading zone".

[0033] (2) The present invention can realize real-time dynamic evaluation of the damage degree of the unloading zone through calculation, thereby providing appropriate support timing for support measures; and promote the development of unloading damage evaluation of deep-cut rock high slopes from "qualitative and semi-quantitative stage" to "fine quantification".

[0034] (3) The present invention can break through the previous single evaluation of unloading damage of deep-cut rock high slopes. It adds the unloading damage factors caused by engineering disturbance, rock mass degradation, and environmental evolution. The evaluation system will be more comprehensive and can realize quantitative evaluation of multi-factor coupling. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments disclosed in the present invention, the drawings of the embodiments will be briefly introduced below. These drawings are only used for illustrative purposes and are not intended to limit the scope of protection of the present invention.

[0036] Figure 1 This is a schematic diagram of the model for determining the range of the unloading zone of a deep-cut rock high slope by coupling the acoustic wave test and the borehole elastic modulus test of the present invention. DETAILED DESCRIPTION

[0037] The following further describes the technical solutions (including preferred technical solutions) of the present invention through accompanying drawings and by enumerating some optional embodiments of the present invention. It should be understood that the embodiments described are merely some, and not all, of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0038] The dynamic evaluation method for unloading damage of deep-cut rock high slopes includes the following steps:

[0039] 1) Conduct on-site surveys to determine the excavation scope of deep-cut rock slopes; determine the physical and mechanical parameters of deep-cut rock slopes based on field tests; test the wave velocity values ​​at different locations on the slopes based on acoustic wave tests; test the deformation modulus at different locations on the slopes based on borehole elastic modulus tests; and conduct indoor tests to determine the baseline wave velocity value S0 and the baseline deformation modulus E0 of undamaged deep-cut rock slopes.

[0040] 2) If Figure 1 As shown in the figure, based on the acoustic wave test and borehole elastic modulus test in step 1), a model for determining the range of the unloading zone of a deep-cut rock high slope coupled with the acoustic wave test and the borehole elastic modulus test is established as follows:

[0041] (Formula 1)

[0042] (Equation 2)

[0043]

[0044] Where, q refers to the demarcation coefficient of the unloading area, q （x,z） Refers to the circle coefficient at the (x, z) coordinate; γ （x,z） Refers to the model correction coefficient; α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of the deformation modulus test at the (x, z) coordinate; S0 refers to the reference wave velocity value when the deep rock high slope is not damaged, S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock slope is unloaded; E0 refers to the reference deformation modulus value when the deep rock slope is not damaged, E （x,z） It refers to the deformation modulus value at the (x, z) coordinate when the deep rock high slope is unloaded; a refers to the sensitivity coefficient of the acoustic wave test, and b refers to the sensitivity coefficient of the deformation modulus test.

[0045] Among them, the acoustic wave test sensitivity coefficient a and the deformation modulus test sensitivity coefficient b are determined according to the physical and mechanical parameters of the deep-cut rock high slope. When the ratio of the wave velocity test value at the point to the benchmark wave velocity value is greater than or equal to 0.8, a is taken as 1; when the ratio of the wave velocity test value at the point to the benchmark wave velocity value is less than 0.8, a is taken as 1.1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is greater than or equal to 0.8, b is taken as 1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is less than 0.8, b is taken as 1.1.

[0046] The importance coefficient α of the acoustic wave test at the (x, z) coordinate （x,z） and deformation modulus test importance coefficient β （x,z） The calculation formula is as follows:

[0047] (Formula 4)

[0048] (Formula 5)

[0049] in, (Equation 6)

[0050] (Equation 7)

[0051] Where, α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of deformation modulus test at (x, z) coordinate; S 归一化（x,z） Refers to the normalized acoustic wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; μ sRefers to the mean of all wave velocity values ​​of deep-cut rock high slope, σ s Refers to the standard deviation of all acoustic wave velocity values ​​on deep-cut rock slopes; S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; E 归一化（x,z） Refers to the normalized deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; E （x,z） Refers to the deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; μ d Refers to the mean value of all deformation modulus values ​​of deep rock high slope, σ d Refers to the standard deviation of all deformation modulus values ​​of deep rock high slopes.

[0052] 3) Based on the calculation results of the model for determining the unloading area of ​​deep-cut rock high slopes in step 2), the scope of the unloading damage area of ​​deep-cut rock high slopes is determined as follows:

[0053] The formula for establishing the unloading area range is as follows:

[0054] (Equation 9)

[0055] Where G （x,z） Refers to the discriminant formula of whether the coordinate (x, z) enters the unloading area; G 进入卸荷区（x,z） It means entering the unloading zone at the (x, z) coordinate; G 未进入卸荷区（x,z） Refers to not entering the unloading area at the (x, z) coordinate; q （x,z） Refers to the circle coefficient at the (x,z) coordinate.

[0056] When the calculated q （x,z） When the value is greater than or equal to 0.18, the coordinate point is the unloading area; all coordinate points in the unloading area are determined as the range of the unloading damage area of ​​the deep rock high slope.

[0057] 4) Calculate the comprehensive evaluation coefficient H of unloading damage at each coordinate point in the unloading damage area of ​​deep-cut rock slope according to the refined evaluation model of unloading damage in step 3. （x,z） ;

[0058] The refined evaluation model for unloading damage is established based on the coupling of multiple factors including engineering disturbance, rock mass degradation, and environmental evolution. The refined evaluation model for unloading damage is as follows:

[0059] (Equation 8)

[0060] Where H （x,z） Refers to the comprehensive evaluation coefficient of unloading damage at the (x, z) coordinate; e refers to the natural constant; M and N refer to the comprehensive influence constant; δ g(x,z)Refers to the unloading damage strain caused by engineering disturbance factors at the (x, z) coordinate, which is obtained from the on-site engineering disturbance strain test; δ y(x,z) Refers to the unloading damage strain caused by rock mass degradation factors at the (x, z) coordinate, which is obtained from the on-site rock mass degradation strain test; δ h(x,z) Refers to the unloading damage strain caused by environmental evolution factors at the (x, z) coordinate, which is obtained from the on-site environmental evolution strain test; δ j It refers to the ultimate strain of unloading damage, which is obtained from the on-site ultimate tensile strain test; θ refers to the stress coefficient.

[0061] M is taken as 1.0 or 1.1, and N is taken as 1.0 or 1.1. When the impact of engineering disturbance, rock mass degradation, and environmental evolution is strong, M and N are both taken as 1.1; when the impact of engineering disturbance, rock mass degradation, and environmental evolution is not strong, M and N are both taken as 1.0. θ refers to the emphasis coefficient, which is taken as 0.9 when the unloading damage at the (x, z) coordinate is strong, and is taken as 1.0 when the unloading damage at the (x, z) coordinate is not strong.

[0062] 5) Based on the unloading damage comprehensive evaluation coefficient H of each coordinate point calculated in step 4) （x,z） The dataset K is arranged from large to small. The coordinate point area corresponding to the first 40% of the dataset K is defined as the strong unloading area, the coordinate point area corresponding to the middle 40% to 70% of the dataset K is defined as the weak unloading area, and the coordinate point area corresponding to the last 30% of the dataset K is defined as the slight unloading area; that is:

[0063] (Equation 10)

[0064] Where J is the judgment formula for the degree of unloading damage, J1 refers to the strong unloading area, J2 refers to the weak unloading area, and J3 refers to the micro-unloading area.

[0065] The evaluation method of the present invention is further described below with reference to specific examples.

[0066] The abutment slope of a hydropower station in southwest China is a typical deep-cut rock slope, with a maximum height of 320 meters and predominantly granite. Previous calculations for evaluating unloading damage in deep-cut rock slopes have been limited by the use of a single factor in quantitative evaluation and the inability to reflect the dynamic evolution of damage during excavation. Based on the proposed patented technical solution, the following dynamic evaluation process for unloading damage in deep-cut rock slopes was performed.

[0067] (1) For a hydropower station abutment slope in the southwest region, based on the acoustic wave test, the wave velocity values ​​at different positions of the slope from coordinate point 1 to coordinate point 10 were obtained; based on the borehole elastic modulus test, the deformation modulus at the positions of coordinate point 1 to coordinate point 10 was obtained. The data obtained from the slope test are shown in Table 1:

[0068] Table 1 Test values ​​at different positions based on acoustic wave test and drilling elastic modulus test

[0069] Based on indoor tests on samples taken on site, it was found that the benchmark wave velocity value of this deep rock high slope when it was undamaged was 4500 m / s and the benchmark deformation modulus was 25 GPa.

[0070] (2) Taking coordinate point 1 as an example, according to the established “determination model of the unloading zone range of deep-cut rock high slopes by coupling acoustic wave test and elastic modulus test”, the formula for the delineation coefficient of the unloading zone range of coordinate point 1 can be obtained according to (Equation 1):

[0071]

[0072] Where q1 refers to the circumscription coefficient at coordinate point 1; γ1 refers to the model correction coefficient, which is taken as 1.1 because only the acoustic wave test velocity value at this point is not lower than the average value; S0 refers to the benchmark velocity value when the deep rock high slope is undamaged, which is 4500 m / s; E0 refers to the benchmark deformation modulus value when the deep rock high slope is undamaged, which is 25 GPa; a refers to the acoustic wave test sensitivity coefficient, and b refers to the deformation modulus test sensitivity coefficient. The value is determined according to the physical and mechanical properties of the deep rock high slope. Since the ratio of the test value to the benchmark value at this point is greater than 0.8, it is taken as 1.

[0073] α1 refers to the importance coefficient of the acoustic wave test at coordinate point 1, and β1 refers to the importance coefficient of the deformation modulus test at coordinate point 1. Substituting into (Equation 4)-(Equation 7) yields:

[0074]

[0075]

[0076]

[0077]

[0078] Where S 归一化（1） Refers to the normalized acoustic wave velocity value at coordinate point 1 when the deep rock high slope is unloaded; μ s Refers to the mean of all wave velocity values, σ s Refers to the standard deviation of all sound wave velocity values; E 归一化（1） Refers to the normalized deformation modulus value at coordinate point 1 when the deep rock high slope is unloaded; μ d Refers to the mean of all deformation modulus values, σ d Refers to the standard deviation of all deformation modulus values.

[0079] Therefore, by substituting the above values ​​into (Equation 1)-(Equation 3), we can obtain the value of the circle coefficient q1 of coordinate point 1:

[0080]

[0081] According to the above process, the values ​​of the remaining 9 coordinate points are calculated respectively, as shown in the following table:

[0082] Table 2 The circle coefficients from coordinate point 1 to coordinate point 10

[0083] According to (Equation 9), when q （x,z） When the value is greater than or equal to 0.18, it is determined to be the unloading area. In Table 2, coordinate points 1, 4, and 7 enter the unloading area.

[0084] Based on on-site strain testing, the unloading damage limit strain in this area is 0.35%. The unloading strains of coordinate points 1, 4, and 7 are shown in Table 3:

[0085] Table 3 Unloading strains at coordinate points 1, 4, and 7

[0086] Unloading damage strain caused by engineering disturbance factors Unloading damage strain caused by rock mass deterioration factors Unloading damage strain caused by environmental evolution factors Coordinate point 1 0.05% 0.05% 0.02% Coordinate point 4 0.06% 0.05% 0.02% Coordinate point 7 0.04% 0.04% 0.02%

[0087] Substituting the unloading strains of coordinate points 1, 4, and 7 into (Equation 8) yields:

[0088]

[0089]

[0090]

[0091] Where H1 refers to the comprehensive evaluation coefficient of unloading damage at coordinate point 1; H4 refers to the comprehensive evaluation coefficient of unloading damage at coordinate point 4; and H7 refers to the comprehensive evaluation coefficient of unloading damage at coordinate point 7.

[0092] The comprehensive evaluation coefficient value H of the unloading damage at each coordinate point （x,z） Arrange the data set K from large to small,

[0093]

[0094] The coordinate point area corresponding to the first 40% of the K ranking of the data set is defined as the strong unloading area, and the coordinate point area corresponding to 0.3478 is the strong unloading area;

[0095] The coordinate point area corresponding to the middle 40% to 70% of the K ranking of the data set is defined as the weak unloading area, and the coordinate point area corresponding to 0.2903 is the weak unloading area;

[0096] The coordinate point area corresponding to the 30% after the K sorting of the data set is defined as the micro-unloading area, and the coordinate point area corresponding to 0.2422 is the micro-unloading area.

[0097] In summary, coordinate point 1 is the weak unloading area; coordinate point 4 is the strong unloading area; coordinate point 7 is the micro unloading area.

[0098] It will be easily understood by those skilled in the art that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

Claims

1. A dynamic evaluation method for unloading damage of deep-cut rock high slopes, characterized by: The steps include: 1) Conduct on-site surveys to determine the excavation scope of deep-cut high rock slopes; determine the physical and mechanical parameters of deep-cut high rock slopes based on field tests; Based on the acoustic wave test, the wave velocity values ​​at different positions on the high slope are tested; Based on the borehole elastic modulus test, the deformation modulus at different locations of the high slope was tested; indoor tests were carried out to determine the reference wave velocity value S0 and the reference deformation modulus E0 of the deep rock high slope when it was not damaged; 2) Based on the acoustic wave test and borehole elastic modulus test in step 1), a model for determining the range of the unloading zone of the deep-cut rock high slope is established by coupling the acoustic wave test and the borehole elastic modulus test; 3) Determine the extent of the unloading damage area of ​​the deep-cut rock high slope based on the calculation results of the model for determining the extent of the unloading area of ​​the deep-cut rock high slope in step 2); 4) Calculate the comprehensive evaluation coefficient of unloading damage for each coordinate point within the unloading damage area of ​​the deep-cut rock slope in step 3) based on the refined evaluation model of unloading damage; 5) Evaluate based on the comprehensive evaluation coefficient of unloading damage at each coordinate point calculated in step 4).

2. The method for dynamic evaluation of unloading damage of deep-cut rock high slopes according to claim 1 is characterized by: In step 2), the model for determining the unloading zone range of the deep-cut rock high slope by coupling the acoustic wave test and the borehole elastic modulus test is as follows: (Formula 1) (Equation 2) (Formula 3) Where, q refers to the demarcation coefficient of the unloading area, q （x,z） Refers to the circle coefficient at the (x, z) coordinate; γ （x,z） Refers to the model correction coefficient; α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of the deformation modulus test at the (x, z) coordinate; S0 refers to the reference wave velocity value when the deep rock high slope is not damaged, S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock slope is unloaded; E0 refers to the reference deformation modulus value when the deep rock slope is not damaged, E （x,z） It refers to the deformation modulus value at the (x, z) coordinate when the deep rock high slope is unloaded; a refers to the sensitivity coefficient of the acoustic wave test, and b refers to the sensitivity coefficient of the deformation modulus test.

3. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 2 is characterized by: In the step 2), the values ​​of the acoustic wave test sensitivity coefficient a and the deformation modulus test sensitivity coefficient b are determined according to the physical and mechanical parameters of the deep-cut rock high slope. When the ratio of the wave velocity test value at the point to the benchmark wave velocity value is greater than or equal to 0.8, a is 1; when the ratio of the wave velocity test value at the point to the benchmark wave velocity value is less than 0.8, a is 1.1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is greater than or equal to 0.8, b is 1; when the ratio of the deformation modulus test value at the point to the benchmark deformation modulus is less than 0.8, b is 1.

1.

4. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 2 is characterized by: In step 2), the importance coefficient α of the acoustic wave test at the (x, z) coordinate （x,z） and deformation modulus test importance coefficient β （x,z） The calculation formula is as follows: (Formula 4) (Formula 5) in, (Equation 6) (Equation 7) Where, α （x,z） Refers to the importance coefficient of the acoustic wave test at the (x, z) coordinate, β （x,z） Refers to the importance coefficient of deformation modulus test at (x, z) coordinate; S 归一化（x,z） Refers to the normalized acoustic wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; μ s Refers to the mean of all wave velocity values ​​of deep-cut rock high slope, σ s Refers to the standard deviation of all acoustic wave velocity values ​​on deep-cut rock slopes; S （x,z） Refers to the wave velocity value at the (x, z) coordinate when the deep rock high slope is unloaded; E 归一化（x,z） Refers to the normalized deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; E （x,z） Refers to the deformation modulus value at the (x, z) coordinate when the deep rock slope is unloaded; μ d Refers to the mean value of all deformation modulus values ​​of deep rock high slope, σ d Refers to the standard deviation of all deformation modulus values ​​of deep rock high slopes.

5. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 2 is characterized by: In step 3), the range of the unloading damage area of ​​the deep-cut rock high slope is determined according to the calculation results of the deep-cut rock high slope unloading area range determination model in step 2), specifically as follows: When the calculated q （x,z） When the value is greater than or equal to 0.18, the coordinate point is the unloading area; all coordinate points in the unloading area are determined as the range of the unloading damage area of ​​the deep rock high slope.

6. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 5 is characterized by: In step 4), the unloading damage refinement evaluation model is as follows: (Equation 8) Where H （x,z） Refers to the comprehensive evaluation coefficient of unloading damage at the (x, z) coordinate; e refers to the natural constant; M and N refer to the comprehensive influence constant; δ g(x,z) Refers to the unloading damage strain caused by engineering disturbance factors at the (x, z) coordinate; δ y(x,z) Refers to the unloading damage strain caused by rock mass degradation factors at the (x, z) coordinate; δ h(x,z) Refers to the unloading damage strain caused by environmental evolution factors at the (x, z) coordinate; δ j refers to the unloading damage limit strain; θ refers to the stress coefficient.

7. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 6, characterized in that: The M is taken as 1.0 or 1.1, and the N is taken as 1.0 or 1.1; when the impact of engineering disturbance, rock mass degradation, and environmental evolution is strong, M and N are both taken as 1.1; when the impact of engineering disturbance, rock mass degradation, and environmental evolution is not strong, M and N are both taken as 1.

0.

8. The method for dynamic evaluation of unloading damage of deep-cut rock high slope according to claim 1 is characterized by: In step 5), the values ​​of the comprehensive evaluation coefficient of unloading damage of each coordinate point calculated in step 4) are arranged from large to small to obtain data set K. The coordinate point area corresponding to the first 40% of the data set K is defined as a strong unloading area, the coordinate point area corresponding to the middle 40% to 70% of the data set K is defined as a weak unloading area, and the coordinate point area corresponding to the last 30% of the data set K is defined as a micro unloading area.

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