Method for predicting the time-dependent deformation of excavation-damaged rock materials at a predetermined location in the surrounding rock

Abstract

The embodiments of the present application relate to the technical field of surrounding rock deformation monitoring, and specifically to a method for predicting the time-dependent deformation of rock materials damaged by excavation at a predetermined position of the surrounding rock. The time-dependent deformation is caused by the excavation of the surrounding rock and further expanded under the long-term action of ground stress, and includes the following steps: S10: determining the distance between the predetermined position and the excavation position of the surrounding rock; S20: determining the time interval between the prediction time and the excavation time; S30: determining the excavation damage at the predetermined position according to the distance and the time interval; S40: determining the material strain at the predetermined position according to the distance and the time interval; S50: predicting the time-dependent deformation of the rock materials at the predetermined position of the surrounding rock according to the excavation damage and the material strain. The above method can determine the excavation damage and the material strain degree of the rock materials at the predetermined position of the surrounding rock at any time, and then accurately determine the time-dependent deformation of the rock materials at the predetermined position of the surrounding rock at any time.

Description

Technical Field

[0001] Embodiments of the present application relate to the technical field of surrounding rock deformation monitoring, and in particular to a method for predicting the time-dependent deformation of excavation-damaged rock materials at a predetermined location of the surrounding rock. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] With the development of the nuclear industry and the increase in demand for nuclear energy, a large amount of radioactive waste is generated during nuclear industry operations. In order to effectively prevent the migration of radioactive nuclides in radioactive waste to the biosphere, it is currently common to set up underground geological disposal sites for radioactive waste to achieve efficient disposal and long-term isolation of radioactive waste. In the process of building a geological disposal site for radioactive waste, excavation operations will cause the stress state of the rock around the excavation location to change, thereby forming a surrounding rock with redistributed stress. Under the long-term action of redistributed stress, the excavation damage inside the surrounding rock continues to develop, resulting in a continuous increase in the time-dependent deformation of the surrounding rock at different locations. The surrounding rock at locations with excessive time-dependent deformation will be unstable and damaged, further causing the radioactive nuclides in the geological disposal site for radioactive waste to migrate to the biosphere. Therefore, when designing and constructing underground facilities, it is necessary to predict and judge the degree of time-dependent deformation of the excavated surrounding rock at different locations and at different time intervals. Summary of the invention

[0004] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0005] An embodiment of the present application provides a method for predicting the time-dependent deformation of rock materials damaged by excavation at a predetermined position of surrounding rock. The time-dependent deformation is caused by the excavation of the surrounding rock and further expanded under the long-term action of ground stress. The method comprises the following steps: S10: determining the distance between the predetermined position and the excavation position of the surrounding rock; S20: determining the time interval between the prediction time and the excavation time; S30: determining the excavation damage at the predetermined position based on the distance and the time interval; S40: determining the material strain at the predetermined position based on the distance and the time interval; S50: predicting the time-dependent deformation of the rock materials at the predetermined position of the surrounding rock based on the excavation damage and the material strain.

[0006] In the embodiments of the present application, by respectively determining the distance between the predetermined position and the excavation position of the surrounding rock, the relationship between the time interval between the prediction and the excavation time and the excavation damage at the predetermined position, as well as the relationship between the distance between the predetermined position and the excavation position of the surrounding rock, the time interval between the prediction and the excavation time and the material strain at the predetermined position, the time-dependent deformation of the rock material at the predetermined position of the surrounding rock at any time is determined from two dimensions: excavation damage and material strain, thereby ensuring the accuracy of the prediction of the time-dependent deformation of the rock material at the predetermined position of the surrounding rock at any time, and further realizing the complete reflection and long-term prediction of the time-dependent deformation process of the excavation damaged rock. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Other objects and advantages of the present application will become apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the present application.

[0008] Figure 1 It is a flow chart for predicting the time-dependent deformation of excavation-damaged rock materials at predetermined locations of surrounding rocks according to an embodiment of the present application.

[0009] Figure 2 It is a schematic diagram of a method for determining parameters of excavation damage at a predetermined location of surrounding rock according to an embodiment of the present application.

[0010] Figure 3 It is a schematic diagram of the change of material strain over time of a rock sample with low excavation damage whose predetermined position is far from the excavation position according to an embodiment of the present application.

[0011] Figure 4 This is a schematic diagram of the change over time of material strain of a rock sample with high excavation damage at a predetermined position close to the excavation position according to an embodiment of the present application.

[0012] Description of reference numerals:

[0013] 10. Surrounding rock;

[0014] 20. On-site rock samples;

[0015] 30. Rock samples for testing;

[0016] 40. Material strain discrete points;

[0017] 50. Prediction curve.

[0018] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0019] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0020] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0021] Excavation operations will cause new cracks to form inside the surrounding rock, which will continue to expand under the continuous action of ground stress, thus affecting the safety and stability of underground facilities. Therefore, before designing and constructing underground facilities, it is necessary to accurately predict the time-dependent deformation of the surrounding rock under different time conditions. At present, complete surrounding rock or surrounding rock materials with artificial prefabricated cracks are usually selected as research objects. However, it is difficult for complete surrounding rock and surrounding rock with artificial prefabricated cracks to simulate the actual damage of the surrounding rock during the construction of underground facilities, and thus it is impossible to accurately and completely reflect the time-dependent deformation process of the surrounding rock damaged by excavation.

[0022] Based on this, an embodiment of the present application provides a method for predicting the time-dependent deformation of excavation-damaged rock materials at a predetermined location of surrounding rock, where the time-dependent deformation is caused by the excavation of the surrounding rock and further expanded under the long-term action of ground stress. Figure 1 FIG. 1 is a flow chart for predicting the time-dependent deformation of excavation-damaged rock materials at predetermined locations of surrounding rock according to an embodiment of the present application. Figure 1 As shown, it includes the following steps: S10: determining the distance between the predetermined position and the excavation position of the surrounding rock; S20: determining the time interval between the prediction time and the excavation time; S30: determining the excavation damage at the predetermined position according to the distance and the time interval; S40: determining the material strain at the predetermined position according to the distance and the time interval; S50: predicting the time-dependent deformation of the rock material at the predetermined position of the surrounding rock according to the excavation damage and the material strain.

[0023] In the embodiments of the present application, by respectively determining the distance between the predetermined position and the excavation position of the surrounding rock, the relationship between the time interval between the prediction and the excavation time and the excavation damage at the predetermined position, as well as the relationship between the distance between the predetermined position and the excavation position of the surrounding rock, the time interval between the prediction and the excavation time and the material strain at the predetermined position, the time-dependent deformation of the rock material at the predetermined position of the surrounding rock at any time is determined from two dimensions: excavation damage and material strain, thereby ensuring the accuracy of the prediction of the time-dependent deformation of the rock material at the predetermined position of the surrounding rock at any time, and further achieving a complete reflection and long-term prediction of the time-dependent deformation process of excavation-damaged rock.

[0024] In some embodiments, in step S30, the distance, time interval, and excavation damage conform to the following expression:

[0025] (1).

[0026] Where D(d,t) represents the excavation damage at the predetermined position, d represents the distance between the predetermined position and the excavation position of the surrounding rock, t represents the time interval from the prediction time to the excavation time, u, v, w, α represent parameters, and e represents a natural constant.

[0027] In the embodiments of the present application, the time development and the continuous effect of external stress on the excavation damage at the predetermined position of the surrounding rock are combined, and based on the strain equivalence principle, the distance between the predetermined position and the excavation position of the surrounding rock, and the time interval between the prediction time and the excavation time, the time-dependent extended expression of the excavation damage is determined to accurately determine the excavation damage corresponding to the predetermined position of the surrounding rock at the predetermined time interval, thereby achieving accurate prediction of the excavation damage at the predetermined position of the surrounding rock at any time.

[0028] In some embodiments, u, v, and w are parameters that affect the damage range inside the surrounding rock and are related to the lithology of the surrounding rock and the excavation method.

[0029] In some embodiments, α is a parameter that controls the rate at which excavation damage develops over time.

[0030] In some embodiments, when time t=0, the excavation damage at the predetermined position is the initial excavation damage; when time t tends to infinity, the excavation damage at the predetermined position approaches 1, indicating that the excavation damage at the predetermined position of the surrounding rock has undergone unstable failure.

[0031] In some embodiments, in step S40, the distance, time interval, and material strain at the predetermined position conform to the following expression:

[0032] (2).

[0033] in, represents the material strain at the predetermined position, d represents the distance between the predetermined position and the excavation position of the surrounding rock, t represents the time interval from the prediction time to the excavation time, S ij represents the deviatoric stress tensor at a predetermined location, which can be obtained by measuring the ground stress at the excavation site; σ m represents the spherical stress tensor at the predetermined position, which can be obtained by measuring the ground stress at the excavation site; G0 and G1 represent the shear modulus at the predetermined position; K0 represents the bulk modulus at the predetermined position; η1 and η2 represent the viscosity coefficient; α, β, γ, u, v, w represent parameters; e represents the natural constant, δ ij represents the Kronecker function, represents the generalized Mittag-Leffler function, Represents the Gamma function.

[0034] In an embodiment of the present application, the influence of time and external stress on the material strain at a predetermined position of the surrounding rock is combined, and an expression for the material aging deformation is determined based on the distance between the predetermined position and the excavation position of the surrounding rock and the time interval between the prediction time and the excavation time, so as to accurately predict the material strain degree corresponding to the predetermined position of the surrounding rock at the predetermined time interval based on the expression, thereby further realizing long-term prediction of the strain degree of the surrounding rock material.

[0035] In some embodiments, expression (2) represents the material strain expression of rock material under time development and external stress conditions in three-dimensional space. It represents the material strain at the predetermined position of the surrounding rock under triaxial stress conditions. The material strain includes three parts: elastic strain, viscous strain and viscoplastic strain, and the value of the material strain is the sum of the values ​​of the three strains: elastic strain, viscous strain and viscoplastic strain.

[0036] In some embodiments, γ is a fractional differential derivative.

[0037] In some embodiments, S ij and σ m It can be obtained by measuring the ground stress at the excavation location.

[0038] In some embodiments, , which is the generalized Mittag-Leffler function.

[0039] Figure 2 FIG. 1 is a schematic diagram of a method for determining parameters of excavation damage at a predetermined location of surrounding rock according to an embodiment of the present application. Figure 2As shown, in some embodiments, u, v, and w are determined by the following steps: obtaining an on-site rock sample 20 of the surrounding rock 10 at a time t approximately equal to 0 after excavation; preparing a rock sample 30 for testing using the on-site rock sample 20; testing the rock samples to determine the excavation damage of the rock samples at different distances from the excavation location; determining a relationship between the distance and the excavation damage based on the distance between the rock sample 30 for testing and the excavation location and the excavation damage; and determining the values ​​of u, v, and w based on the relationship.

[0040] In the embodiment of the present application, the rock samples 20 at different distances from the excavation position at the time t approximately equal to 0 after excavation are obtained and processed to obtain the rock samples 30 for testing. According to the obtained rock samples 30 for testing, the distance of the rock sample from the excavation position, the excavation damage, and the relationship between the distance and the excavation damage are determined, so as to obtain the parameters u, v, and w that affect the range of internal damage of the rock under real geological conditions, and then obtain the time-dependent extended expression (1) of the excavation damage of the rock sample at any time under real geological conditions, so as to achieve accurate prediction of the excavation damage of the rock sample at any time under real geological conditions.

[0041] In some embodiments, the excavated damaged rock can be processed by a cutting tool to obtain an on-site rock sample 20. The on-site rock sample 20 can be a rectangular parallelepiped or cylindrical shape, with a side length or diameter of not less than 10 cm, and the distance between the rock sample and the excavation location is not less than 30 cm. For example, the excavated damaged rock can be drilled and cored by a coring drill to obtain a plurality of cylindrical on-site rock samples 20 that meet the size requirements.

[0042] In some embodiments, the obtained on-site rock sample 20 can be processed along the direction from the excavation position to the inside of the rock mass to obtain multiple rock samples of the same size and at different distances from the excavation position. For example, the ratio of the height to the diameter of the rock sample 30 used for testing is set to 2. Since the damaged area of ​​the surrounding rock 10 caused by mechanical underground excavation is usually small, and the deepest crack extension range is about 1-2 cm, the diameter or side length of the rock sample 30 used for testing can be set to 2-2.5 cm. For example, the on-site rock sample 20 can be processed by drilling and grinding to obtain multiple rock samples 30 for testing.

[0043] In some embodiments, when determining the excavation damage of a rock sample, the following steps are used: determining the wave velocity of the rock sample 30 used for testing; and determining the excavation damage of the rock sample based on the wave velocity.

[0044] In the embodiment of the present application, by determining the relationship between the wave velocity of the rock sample 30 for testing and the excavation damage of the rock sample, the excavation damage of the rock sample can be further determined or verified by determining the wave velocity of the rock sample 30 for testing.

[0045] In some embodiments, when determining the wave velocity of the rock sample 30 for testing, the following steps are used: numbering the rock sample 30 for testing; testing the numbered rock samples to determine the wave velocity corresponding to the rock samples.

[0046] In some embodiments, in order to facilitate testing and processing, the obtained rock samples 30 for testing can be numbered along the direction from the excavation position to the inside of the rock mass. For example, the first rock sample close to the excavation position can be numbered as 1, and the last rock sample can be numbered as n. Since the internal damage of the rock sample close to the excavation position is greater, there are differences in the damage area caused to the surrounding rock 10 when the mechanical method and the drilling and blasting method are used for underground excavation operations, and the damage area of ​​the surrounding rock 10 caused by the mechanical method is usually smaller than the damage area of ​​the surrounding rock 10 caused by the drilling and blasting method. Therefore, when the mechanical method is used for underground excavation operations, the number of rock samples for predicting the time-dependent deformation of the excavation damage of the surrounding rock 10 is set to n≥5; when the drilling and blasting method is used for underground excavation operations, the number of rock samples for predicting the time-dependent deformation of the excavation damage of the surrounding rock 10 is set to n≥15. By adopting different n settings, the above-mentioned parameters determined can more accurately and comprehensively reflect the actual excavation process, so that the determined excavation damage can accurately reflect the actual situation.

[0047] In some embodiments, an ultrasonic detector may be used to sequentially test the wave velocity of the numbered rock samples to obtain the wave velocity corresponding to each rock sample. The wave velocity of the i-th rock sample 30 used for testing is denoted as V i .

[0048] In some embodiments, the wave velocity and excavation damage satisfy the following expressions:

[0049] (3).

[0050] in, represents the excavation damage of the i-th rock sample, V i represents the wave velocity of the ith rock sample, V n represents the wave velocity of the nth rock sample.

[0051] In the embodiments of the present application, by determining the expressions of wave velocity and excavation damage, the excavation damage corresponding to the rock sample can be accurately determined or verified according to the wave velocity corresponding to the rock sample.

[0052] In some embodiments, the relationship between distance and excavation damage is determined by the following steps: based on the wave velocity of the rock sample 30 for testing at the time t approximately equal to 0 after excavation and expression (3), the excavation damage of the rock sample 30 for testing is determined; based on the distance of the rock sample from the excavation location and the excavation damage, excavation damage discrete points related to distance and excavation damage are determined; based on the determined excavation damage discrete points, the relationship between distance and excavation damage is determined.

[0053] In some embodiments, the wave velocity of the rock sample 30 for testing at the time t after excavation approximately equal to 0 is substituted into expression (3) to obtain the excavation damage of the rock sample 30 for testing. The excavation damage of the i-th rock sample 30 for testing is recorded as .

[0054] In some embodiments, the distance between the rock sample and the excavation position at the time t approximately equal to 0 after excavation can be determined based on the distance between the center point of the rock sample and the excavation position. The distance between the i-th rock sample 30 used for testing and the excavation position is recorded as d i .

[0055] In some embodiments, the excavation damage discrete point corresponding to the rock sample 30 for testing at the time t approximately equal to 0 after excavation and the distance from the excavation position is determined. The excavation damage discrete point of the i-th rock sample 30 for testing is recorded as (d i ,D i ).

[0056] In some embodiments, the excavation damage discrete points (d i ,D i ), determine the relationship between the distance d and the excavation damage D(d,t) when time t is approximately equal to 0.

[0057] In some embodiments, the parameters u, v, w in expression (1) can be determined by comparing the relationship between the distance determined by the above-mentioned test method and the excavation damage at the time when time t is approximately equal to 0 and expression (1), thereby obtaining a time-dependent extended expression (1) that can reflect the excavation damage of rock samples under real geological conditions, so as to realize the prediction of the excavation damage process of rock samples under real geological conditions.

[0058] In some embodiments, discrete points of surrounding rock excavation damage at time t approximately equal to 0 after excavation are distributed on a schematic diagram of excavation damage versus distance, wherein the ordinate of the diagram is the excavation damage D(d,t), and the abscissa is the distance d between the rock sample and the excavation position.

[0059] In some embodiments, the excavation damage discrete point (d i ,D i ) is consistent with the prediction curve trajectory of expression (1) after determining the parameters u, v, and w.

[0060] In some embodiments, the following experimental method is used to determine the parameters: α, β, γ, G0, G1, K0, η1, η2, which are specifically determined by the following steps: obtaining an on-site rock sample 20 of the surrounding rock 10 at a time t approximately equal to 0 after excavation; preparing a rock sample 30 for testing using the on-site rock sample 20; testing the rock samples to determine the material strain of the rock samples at different distances from the excavation location under different time conditions; determining the relationship between the distance, test time and material strain based on the distance of the rock sample 30 for testing from the excavation location, the test time and the material strain; determining α, β, γ, G0, G1, K0, η1, η2 based on the relationship.

[0061] The rock sample 30 for testing is obtained in the same manner as previously described.

[0062] The following is a detailed description of a method for determining the material strain of a rock sample by testing the rock sample 30 for testing.

[0063] In some embodiments, a material strain test is performed on the rock sample 30 for testing at a time t approximately equal to 0 after excavation, and the distance d between the center point of the rock sample 30 for testing and the excavation position, as well as the material strain corresponding to the rock sample 30 for testing at different test times are recorded. The test time of the i-th time interval is recorded as t i , the material strain at the i-th time interval is recorded as i .

[0064] In some embodiments, a triaxial creep test is performed on the rock sample 30 for testing at a time t approximately equal to 0 after excavation. A rock sample with a larger excavation damage at a predetermined position close to the excavation position and a rock sample with a smaller excavation damage at a predetermined position far from the excavation position are selected for triaxial creep tests respectively. When performing the test, the axial stress of the tested rock sample is set to 80% of the triaxial compressive strength of a complete rock sample of the same lithology, the test duration of each rock sample material strain is set to 24 hours, and multiple time t values ​​are collected within each test duration. i The strain under i .

[0065] According to the test time and material strain of the rock sample for material strain test, the corresponding material strain discrete point is determined. Among them, the material strain discrete point of the i-th time interval is recorded as (t i , i ).

[0066] By fitting the material strain discrete points (t i , i ), determine the time t and material strain The relationship between .

[0067] By comparing the relationship between time and material strain determined by the above-mentioned test method with expression (2), the parameters α, β, γ, G0, G1, K0, η1, η2 in expression (2) are determined, thereby obtaining the material strain expression (2) that can reflect the rock sample under real geological conditions, so as to realize the prediction of the material strain process of the rock sample under real geological conditions.

[0068] Figure 3 It is a schematic diagram of the change of material strain over time of a rock sample with low excavation damage whose predetermined position is far from the excavation position according to an embodiment of the present application. Figure 4 1 is a schematic diagram of the material strain variation over time of a rock sample with high excavation damage at a predetermined position close to the excavation position according to an embodiment of the present application. Figure 3 and Figure 4 As shown in some embodiments, the material strain discrete points at a predetermined position are distributed on the material strain variation diagram over time, wherein the ordinate of the diagram is the material strain. , unit: %; the horizontal axis is time t, unit: hour.

[0069] like Figure 3 and Figure 4 As shown, in some embodiments, a material strain discrete point 40 (t i , i ) is consistent with the trajectory of the predicted curve 50 of expression (2) after the parameters α, β, γ, G0, G1, K0, η1 and η2 are determined.

[0070] In step S50, a method for predicting the time-dependent deformation of excavation-damaged rock materials at a predetermined position of surrounding rock established by the present invention (expression (2)) is used to simulate and predict the change process of the above two axial strains, and the test results and the simulation prediction results are plotted in the same figure, as shown in FIG. Figure 3 and Figure 4As shown. By comparing the test results with the simulation prediction results, it can be seen that the method for predicting the time-dependent deformation of excavated damaged rock materials at predetermined positions of surrounding rocks established by the present invention can accurately and completely predict the time-dependent deformation of excavated damaged rock materials at predetermined positions of different surrounding rocks at any time, with small prediction error and high accuracy. Substituting the ground stress conditions measured at the excavation site and the parameters u, v, w, α, β, γ, G0, G1, K0, η1 and η2 obtained in steps S30 and S40 into expression (2), the time-dependent deformation of excavated damaged rock materials at predetermined positions of different surrounding rocks at any time can be predicted.

[0071] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0072] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for predicting the time-dependent deformation of excavation-damaged rock materials at a predetermined location of surrounding rock, wherein the time-dependent deformation is caused by the excavation of the surrounding rock and further expanded under the long-term action of ground stress, characterized in that: It includes the following steps: S10: Determine the distance between the predetermined position and the excavation position of the surrounding rock; S20: determining the time interval between the prediction time and the excavation time; S30: determining excavation damage at the predetermined position according to the distance and the time interval; S40: determining a material strain at the predetermined position according to the distance and the time interval; S50: predicting the time-dependent deformation of the rock material at the predetermined position of the surrounding rock according to the excavation damage and the material strain; In the step S30, the distance, the time interval and the excavation damage conform to the following expression: ； in, D ( d , t ) represents the excavation damage at the predetermined position, d represents the distance between the predetermined position and the excavation position of the surrounding rock, t It indicates the time interval between prediction and excavation. u, v, w represents the parameters that affect the internal damage range of the surrounding rock, α represents the parameter that controls the rate at which the excavation damage develops over time, e represents a natural constant; In the step S40, the distance, the time interval and the material strain at the predetermined position conform to the following expression: ； in, represents the material strain at the predetermined location, d represents the distance between the predetermined position and the excavation position of the surrounding rock, t It indicates the time interval between prediction and excavation. S ij The deviator stress tensor representing the predetermined position can be obtained by measuring the in-situ stress at the excavation site; σ m The spherical stress tensor representing the predetermined position can be obtained by measuring the ground stress at the excavation site; G 0 and G 1 represents the shear modulus at the predetermined location; K 0 represents the bulk modulus at the predetermined location; η 1 and η 2 represents the viscosity coefficient; α , β represents the parameter that controls the rate at which the excavation damage develops over time, γ represents the fractional differential derivative, u , v , w represents the parameters that affect the internal damage range of the surrounding rock, e represents a natural constant, δ ij represents the Kronecker function, represents the generalized Mittag-Leffler function, Represents the Gamma function.

2. The method according to claim 1, characterized in that: Said u , v , w Use the following steps to determine: Get the time after excavation t An in situ rock sample of the surrounding rock at approximately time zero; preparing a rock sample for testing using the field rock sample; Testing the rock samples to determine excavation damage to the rock samples at different distances from the excavation location; Determining a relationship between the distance and the excavation damage according to the distance between the rock sample for testing and the excavation location and the excavation damage; According to the relationship, determine the u , v , w .

3. The method according to claim 2, characterized in that When determining the excavation damage of the rock sample, the following steps are used: determining the wave velocity of the rock sample used for testing; Based on the wave velocity, excavation damage of the rock sample is determined.

4. The method according to claim 3, characterized in that The wave velocity and the excavation damage satisfy the following expressions: ； in, Indicates i excavation damage of the rock samples, V i Indicates i The wave velocity of a rock sample, V n Indicates n The wave velocity of a rock sample.

5. The method according to claim 1, characterized in that Said α , β , γ , G 0. G 1. K 0. η 1. η 2 Determine using the following steps: obtaining an in situ rock sample of the surrounding rock; preparing a rock sample for testing using the field rock sample; Testing the rock samples to determine the material strain of the rock samples at different distances from the excavation location under different time conditions; Determine a relationship between the distance, the test time and the material strain according to the distance between the rock sample for testing and the excavation location, the test time and the material strain; According to the relationship, determine the α , β , γ , G 0. G 1. K 0. η 1. η 2.

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