Method for establishing deep hard rock dynamic disturbance three-dimensional mechanical model

Abstract

The invention provides a method for establishing a deep hard rock dynamic disturbance three-dimensional mechanical model, and relates to the technical field of rock mechanical properties and engineering. The method comprises the following steps: carrying out a true triaxial test without power disturbance and a true triaxial test under the action of power disturbance on a deep hard rock taken from a certain tunnel project in the deep part, and recording test data of the whole mechanical behavior process of each test; determining failure modes of the deep hard rocks under different dynamic disturbances by comparing all the tested deep hard rocks; the method comprises the following steps: determining a parameter evolution model of cohesion and an internal friction angle under the dynamic disturbance true triaxial condition by constructing a mechanical model of a deep hard rock under the dynamic disturbance true triaxial condition on the basis of mechanical behavior whole-process test data of the deep hard rock under the dynamic disturbance action and failure modes of the deep hard rock under different dynamic disturbances; according to the method, the mechanical behavior of the hard rock under the influence of multi-source dynamic disturbance can be predicted, and a basis is provided for surrounding rock stability evaluation in the construction process of a deeply-buried hard rock area.

Description

Technical Field

[0001] The present invention relates to the field of rock mechanical properties and engineering technology, and in particular to a method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance. Background Art

[0002] In deep hard rock tunnels, the surrounding rock is exposed to true triaxial high stress. As the tunnel face continues to advance and as vehicles operate after the tunnel opens, the surrounding rock is frequently subjected to multiple dynamic disturbances, including drilling and blasting, TBM (Transporting Machine) methods, seismic waves, rockburst stress waves, and train vibration waves. These dynamic disturbances significantly affect the propagation of stress waves and energy dissipation in the hard rock, leading to complex mechanical behavior under these dynamic disturbances. Traditional static models struggle to accurately describe the dynamic mechanical response of deeply buried hard rock. In fact, they are limited to two-dimensional models or simplified assumptions, failing to fully reflect the true mechanical behavior of hard rock in a three-dimensional, high-stress environment.

[0003] In order to accurately analyze and predict the response of hard rock under dynamic disturbance, it is necessary to develop a new three-dimensional mechanical model establishment method that can comprehensively consider the nonlinearity, anisotropy and influence of dynamic disturbance of hard rock and reflect the deformation and failure of hard rock under dynamic load. Summary of the Invention

[0004] In response to the above-mentioned shortcomings of the existing technology, the present invention analyzes the rock failure and deformation characteristics under different dynamic disturbance factors, and proposes a method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance. The purpose is to predict the mechanical behavior of hard rock under the influence of multi-source dynamic disturbance, and provide a basis for the evaluation of surrounding rock stability during the construction process of deep buried hard rock areas.

[0005] The present invention proposes a method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance, which includes the following steps:

[0006] Conduct true triaxial tests on deep hard rock samples taken from deep tunnel projects without dynamic disturbance, and record the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance;

[0007] Based on the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, true triaxial tests were carried out on deep hard rock taken from deep tunnel projects under dynamic disturbance, and the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance were recorded;

[0008] For deep hard rock after true triaxial test without dynamic disturbance and deep hard rock after true triaxial test with dynamic disturbance, the failure mode of deep hard rock after each test is determined by comparing and analyzing the failure mode of deep hard rock under different dynamic disturbances;

[0009] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed.

[0010] Determine the cohesion based on the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance and internal friction angle Parameter evolution model under true triaxial conditions of dynamic disturbance.

[0011] Furthermore, the specific contents of the true triaxial test on deep hard rock taken from deep tunnel engineering without dynamic disturbance and recording the full process test data of the mechanical behavior of deep hard rock under no dynamic disturbance are as follows:

[0012] For deep tunnel engineering, obtain surrounding rock stress data at different distances from the tunnel face; the surrounding rock stress data includes: intermediate principal stress and minimum principal stress ;

[0013] The stress path is designed based on all the surrounding rock stress data obtained, and according to the designed stress path, a true triaxial test without dynamic disturbance is carried out on the deep hard rock using a dynamic disturbance true triaxial testing machine to obtain the peak strength of the deep hard rock under no dynamic disturbance. , and record the full process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under no dynamic disturbance;

[0014] The full-process test data of the mechanical behavior of deep hard rock under true triaxial action are: stress values ​​and strain values ​​of deep hard rock in three directions under principal stress changes.

[0015] Furthermore, the deep hard rocks used in the hard rock true triaxial stress path test and the deep hard rock dynamic perturbation true triaxial test are standard rock samples cut from the same rock, and all standard rock samples pass the homogeneity test before the test.

[0016] Furthermore, based on the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, a true triaxial test under dynamic disturbance is conducted on deep hard rock taken from a deep tunnel project, and the specific method for recording the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance is as follows:

[0017] According to the peak strength of deep hard rock under no dynamic disturbance Set several different disturbance times;

[0018] Obtain the disturbance wave signal at the tunnel engineering site and generate a disturbance wave time-frequency curve. Extract the frequency range of the disturbance wave from the disturbance wave time-frequency curve. Then, based on the disturbance wave signal at the tunnel engineering site and the frequency range of the disturbance wave, determine several disturbance frequencies through Fourier transform. ;

[0019] Obtain rock wave velocity, rock density and surrounding rock particle velocity at the tunnel engineering site, and calculate several disturbance amplitudes using the measured rock wave velocity, rock density and surrounding rock particle velocity ;

[0020] By traversing all perturbation frequencies and the disturbance amplitude to generate all possible dynamic disturbance conditions;

[0021] Based on the stress path designed in the true triaxial test without dynamic disturbance, the true triaxial test under dynamic disturbance is carried out on the deep hard rock according to different dynamic disturbance conditions. During the test, dynamic disturbance is applied according to several set disturbance timings to obtain the peak strength of the deep hard rock under dynamic disturbance. , and record the full process test data of the mechanical behavior of deep hard rock under dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under dynamic disturbance;

[0022] The full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance include: disturbance time, number of disturbances, strength value, stress value and strain value of deep hard rock under dynamic disturbance.

[0023] Furthermore, for the deep hard rock after the true triaxial test without dynamic disturbance and the deep hard rock after the true triaxial test under dynamic disturbance, the specific content of determining the failure mode of the deep hard rock under different dynamic disturbances by comparing and analyzing the failure mode of the deep hard rock after each test is as follows:

[0024] For any deep hard rock after a true triaxial test without dynamic disturbance or after a true triaxial test under dynamic disturbance, determine the type of crack in the deep hard rock and measure the crack failure angle of the deep hard rock;

[0025] Perform 3D laser scanning on the failure surface of the deep hard rock to obtain the horizontal coordinates of each point on the failure surface. The JRC value of the failure surface is calculated using the horizontal coordinates of each point. Based on the JRC value of the failure surface, it is determined that the failure mode of the deep hard rock from a macro perspective is shear failure, tension failure, or mixed failure.

[0026] Based on the crack type, crack failure angle, and failure mode of the deep hard rock, a representative area is selected from the failure surface of the deep hard rock, and a slice is taken from the failure surface based on the selected representative area. The slice is scanned by an SEM electron microscope to observe and record the microscopic features of the failure surface. Based on the microscopic features of the failure surface, the failure mode of the deep hard rock at a microscopic angle is determined to be shear failure, tension failure, or mixed failure.

[0027] Compare the failure modes of the deep hard rock at a macroscopic perspective and the failure modes of the deep hard rock at a microscopic perspective to see if they are consistent. If they are consistent, determine the failure mode of the deep hard rock. If they are inconsistent, re-evaluate the failure mode of the deep hard rock based on the JRC value of the failure surface and the microscopic characteristics of the failure surface.

[0028] Then, by comparing the failure modes of deep hard rock after true triaxial tests without dynamic disturbance and the failure modes of deep hard rock after true triaxial tests under all dynamic disturbances, the failure modes of deep hard rock under different dynamic disturbances are determined.

[0029] Furthermore, based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, the specific contents of constructing the mechanical model of deep hard rock under dynamic disturbance true triaxial conditions are as follows:

[0030] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure mode of deep hard rock under different dynamic disturbances, the peak strength of deep hard rock under different dynamic disturbance conditions is obtained. The changing rules of the rock mass and the deformation of deep hard rock at each disturbance stage under different dynamic disturbance conditions;

[0031] According to the full stress-strain curve of deep hard rock under dynamic disturbance, the mechanical behavior of deep hard rock under dynamic disturbance is divided into three disturbance stages: elastic deformation stage, plastic deformation stage and irreversible deformation stage.

[0032] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the elastic deformation, plastic deformation and irreversible deformation under dynamic disturbance are calculated respectively.

[0033] According to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed.

[0034] Furthermore, the method for constructing the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is as follows:

[0035] Based on the elastic-plastic constitutive model, the incremental stress-strain relationship of deep hard rock is established according to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance, which can be expressed as:

[0036] ;

[0037] ;

[0038] in represents the stress increment tensor; represents the strain increment tensor; Based on Young's modulus , Poisson's ratio and plastic history Anisotropic elastic stiffness tensor of; plastic history As an internal variable, it represents the inelastic irreversible deformation according to the second law of thermodynamics; is the irrecoverable strain increment of deep hard rock under true triaxial dynamic disturbance conditions; represents the plastic strain increment; Indicates brittleness index;

[0039] For the incremental stress-strain relationship of deep hard rock, the plastic strain increment of deep hard rock under dynamic perturbation true triaxial conditions is determined according to the plastic flow law. At the same time, the irrecoverable strain increment of deep hard rock under dynamic disturbance true triaxial conditions is determined ;

[0040] Then, based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the dynamic disturbance damage factor is determined.

[0041] Furthermore, the dynamic perturbation irrecoverable strain increment of the deep hard rock under the dynamic perturbation true triaxial condition is , expressed as:

[0042] ;

[0043] in In order to consider the average strain fitting generated by a single disturbance for different amplitude disturbances under different stress states; is the dynamic disturbance multiplier; is the disturbance time.

[0044] Furthermore, the dynamic disturbance damage factor is:

[0045] ;

[0046] in is the dynamic disturbance damage factor; and These are all material parameters obtained from the full-process test data of mechanical behavior of deep hard rock under dynamic disturbance. represents the critical stress of dynamic disturbance; is the number of disturbances.

[0047] Furthermore, the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is used to determine the cohesion and internal friction angle The specific content of the parameter evolution model under the true triaxial condition of dynamic disturbance is:

[0048] Based on the full process test data of mechanical behavior of deep hard rock under dynamic disturbance, the initial cohesion is solved and initial internal friction angle , residual cohesion and residual internal friction angle ;

[0049] Combined initial cohesion and initial internal friction angle , residual cohesion , residual internal friction angle and dynamic disturbance damage factors, building cohesion and internal friction angle The parameter evolution model under true triaxial conditions of dynamic disturbance is expressed as:

[0050] ;

[0051] ;

[0052] ;

[0053] ;

[0054] ;

[0055] in Indicates the The increment of internal variables in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; is the positive operator; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage.

[0056] The beneficial effects of adopting the above technical solution are:

[0057] The deformation and fracture characteristics of deep hard rock subjected to true triaxial dynamic perturbation differ from conventional understanding. A mechanical model for hard rock failure under dynamic perturbation considers the irreversible strain induced by dynamic perturbation, proposes a dynamic perturbation influence factor (D), and considers the damaging effects of stress state, perturbation amplitude, perturbation frequency, and number of perturbations on deep hard rock. This improves the reliability of the results used to determine the mechanical behavior of deep hard rock under true triaxial dynamic perturbation, enabling a more accurate description of the fracture process of deep engineering hard rock under stress paths and dynamic perturbation. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a flow chart of a method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance in this embodiment;

[0059] Figure 2 This is a typical stress-strain curve diagram of a true triaxial compression test of deep hard rock excavation in this embodiment;

[0060] Figure 3 This is a typical stress-strain curve of the true triaxial test of deep hard rock dynamic disturbance in this embodiment;

[0061] Figure 4 Schematic diagram of typical macro-micro fracture morphology of deep hard rock dynamic disturbance true triaxial test in this embodiment;

[0062] Figure 5 This is a macroscopic fracture surface scanning result diagram in this embodiment;

[0063] Figure 6 This is a diagram showing the evolution of internal variable parameters under true triaxial deep hard rock dynamic disturbance in this implementation method. DETAILED DESCRIPTION

[0064] For ease of understanding of the present application, the specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thoroughly and comprehensively understood.

[0065] In this embodiment, granite samples taken from a deep hard rock tunnel are used as rock samples to construct and verify the accuracy and rationality of a rock dynamic disturbance failure mechanics model under a true triaxial stress state.

[0066] A method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance in this embodiment is as follows: Figure 1 As shown, the method includes the following processes:

[0067] True triaxial tests were carried out on deep hard rock taken from deep tunnel projects without dynamic disturbance, and the full process test data of the mechanical behavior of deep hard rock under non-dynamic disturbance was recorded.

[0068] The specific contents of the true triaxial test on deep hard rock taken from deep tunnel engineering without dynamic disturbance and recording the full process test data of the mechanical behavior of deep hard rock under the non-dynamic disturbance are as follows:

[0069] For deep tunnel engineering, obtain surrounding rock stress data at different distances from the tunnel face; the surrounding rock stress data includes: intermediate principal stress and minimum principal stress .

[0070] In this embodiment, for a deep tunnel in southwest China, the surrounding rock stress data at different distances from the tunnel face at the construction site of the tunnel are obtained through ground stress inversion and field measurement, and this data is used as the basis for setting stress parameters during the test.

[0071] The stress path is designed based on all the surrounding rock stress data obtained, and according to the designed stress path, a true triaxial test without dynamic disturbance is carried out on the deep hard rock using a dynamic disturbance true triaxial testing machine to obtain the peak strength of the deep hard rock under no dynamic disturbance. , and record the entire process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under no dynamic disturbance.

[0072] The full-process test data of the mechanical behavior of deep hard rock under true triaxial action are: stress values ​​and strain values ​​of deep hard rock in three directions under principal stress changes.

[0073] In this embodiment, granite taken from a deep tunnel in southwest China is made into a true triaxial rock specimen, i.e., deep hard rock. True triaxial tests are carried out under specific confining pressure conditions without dynamic disturbance to obtain the peak strength of the true triaxial rock specimen under these conditions, such as Figure 2 As shown in the figure, the whole process test data of the mechanical behavior of the true triaxial rock specimen is recorded, including the pre-peak and post-peak stress and strain of the deep hard rock in the three directions of principal stress, intermediate principal stress and minimum principal stress under the change of principal stress, and the full stress-strain curve of the deep hard rock under the true triaxial excavation stress path is drawn.

[0074] Based on the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, true triaxial tests were carried out on deep hard rock taken from deep tunnel projects under dynamic disturbance, and the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance were recorded.

[0075] The deep hard rocks used in the hard rock true triaxial stress path test and the deep hard rock dynamic perturbation true triaxial test are all standard rock samples cut from the same rock, and all standard rock samples pass the homogeneity test before the test.

[0076] In this implementation, standard rock samples are cut and polished from rock retrieved on-site. Since naturally occurring rocks are not identical, to minimize the variance in test data, all rock samples used are cut from a single, large rock block, while samples with obvious flaws are eliminated. Acoustic testing is a highly effective method for assessing internal homogeneity. Therefore, this implementation analyzes sample uniformity through acoustic testing, selecting rock samples with good uniformity and ensuring that each standard rock sample produced from the same rock is as close to identical as possible, thereby ensuring the reliability of the test results.

[0077] The specific method for conducting true triaxial tests under dynamic disturbance on deep hard rock taken from a deep tunnel project based on the full-process test data on the mechanical behavior of deep hard rock under no dynamic disturbance, and recording the full-process test data on the mechanical behavior of deep hard rock under dynamic disturbance, is as follows:

[0078] According to the peak strength of deep hard rock under no dynamic disturbance Set several disturbance times.

[0079] In this embodiment, select 、 、 、 、 、 、 As a time of disturbance.

[0080] Obtain the disturbance wave signal at the tunnel engineering site and generate a disturbance wave time-frequency curve. Extract the frequency range of the disturbance wave from the disturbance wave time-frequency curve. Then, based on the disturbance wave signal at the tunnel engineering site and the frequency range of the disturbance wave, determine several disturbance frequencies through Fourier transform. .

[0081] In this embodiment, monitoring equipment is deployed at a deep tunnel engineering site to continuously collect disturbance wave signals at the tunnel engineering site. The collected disturbance wave signals are used to draw a time-frequency curve of the disturbance wave at the tunnel engineering site, thereby obtaining the frequency range of the disturbance wave. The collected disturbance wave signals are subjected to Fourier transform to obtain a spectrum, and several disturbance frequencies are determined within the frequency range of the disturbance wave. .

[0082] Obtain rock wave velocity, rock density and surrounding rock particle velocity at the tunnel engineering site, and calculate several disturbance amplitudes using the measured rock wave velocity, rock density and surrounding rock particle velocity .

[0083] In this embodiment, the rock wave velocity and rock density at the tunnel engineering site are measured by conducting rock wave velocity and density tests at the tunnel engineering site, and the surrounding rock particle velocity at the tunnel engineering site is measured by deploying sensors. Then, the disturbance amplitude is obtained based on the rock wave velocity, rock density and surrounding rock particle velocity at the tunnel engineering site. .

[0084] By traversing all perturbation frequencies and the disturbance amplitude combinations of , generating all possible dynamic disturbance conditions.

[0085] In this embodiment, all disturbance frequencies and the disturbance amplitude Perform permutations and combinations to generate all possible dynamic disturbance conditions, and conduct true triaxial tests under dynamic disturbance by controlling variables.

[0086] Based on the stress path designed in the true triaxial test without dynamic disturbance, the true triaxial test under dynamic disturbance is carried out on the deep hard rock according to different dynamic disturbance conditions. During the test, dynamic disturbance is applied according to several set disturbance timings to obtain the peak strength of the deep hard rock under dynamic disturbance. , and record the full process test data of the mechanical behavior of deep hard rock under dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under dynamic disturbance.

[0087] The full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance include: disturbance time, number of disturbances, strength value, stress value and strain value of deep hard rock under dynamic disturbance.

[0088] In this embodiment, based on the peak strength of deep hard rock without dynamic disturbance, dynamic disturbance is applied to change the disturbance frequency to and the disturbance amplitude As the basis for setting disturbance parameters, several independent true triaxial tests were carried out on deep hard rock under dynamic disturbance to obtain the peak strength of deep hard rock under dynamic disturbance. , determine the influence of dynamic disturbance on rock peak value, and obtain the full process test data of mechanical behavior of deep hard rock under dynamic disturbance, including data such as deformation of dynamic disturbance at each stage, and then draw the full process stress-strain curve of deep hard rock under true triaxial action of dynamic disturbance, such as Figure 3 shown.

[0089] For deep hard rock after true triaxial test without dynamic disturbance and deep hard rock after true triaxial test under dynamic disturbance, the failure mode of deep hard rock under different dynamic disturbances is determined by comparing and analyzing the failure mode of deep hard rock after each test.

[0090] In this embodiment, since the failure mode is the final manifestation of brittle-ductile fracture and macro cracks, by identifying the failure mode of deep hard rock under different dynamic disturbances, the influence of different dynamic disturbance factors on the brittle-ductile fracture and macro cracks of deep hard rock can be analyzed. Specifically, observe the deep hard rock after the test and analyze its macro failure mode. In addition, the three-dimensional laser scanning technology is used to scan the failure surface to obtain the JRC value of the failure surface, and the slices of the failure surface are scanned by SEM electron microscope. From the macro-micro perspective, the failure mode of deep hard rock is comprehensively analyzed, such as Figure 4 and Figure 5 shown.

[0091] The specific content of determining the failure mode of deep hard rock under different dynamic disturbances by comparing and analyzing the failure modes of deep hard rock after true triaxial tests without dynamic disturbance and deep hard rock under true triaxial tests with dynamic disturbance is as follows:

[0092] For any deep hard rock after the true triaxial test under no dynamic disturbance or the deep hard rock after the true triaxial test under dynamic disturbance, take photos of the deep hard rock, observe the type of cracks in the deep hard rock based on the photos, and measure the crack failure angle of the deep hard rock.

[0093] In this implementation, deep hard rock samples from true triaxial stress path tests and deep hard rock dynamic perturbation true triaxial tests were removed and photographed in a supplemental light box to record macroscopic failure patterns. By photographing and recording the macroscopic features of the failure surface, the overall morphology and crack distribution of the failure surface can be determined, including the crack type and measured crack failure angle. This helps identify key areas for 3D laser scanning, ensuring that all important cracks and failure features are captured during the scanning process. It also helps determine the crack propagation direction and key areas, thereby guiding the focus of electron microscope scanning, namely, selecting representative crack areas for sectioning.

[0094] A 3D laser scan is performed on the failure surface of the deep hard rock to obtain the coordinates of each point on the failure surface based on the horizontal plane. The JRC value of the failure surface is calculated using the coordinates of each point on the horizontal plane. According to the JRC value of the failure surface, it is judged that the failure mode of the deep hard rock from a macro perspective is one of shear failure, tension failure or mixed failure.

[0095] In this embodiment, a self-written MATLAB program is used to automatically calculate the JRC value (Joint Roughness Coefficient) of the macroscopic failure surface based on the horizontal coordinate information of each point on the failure surface to determine the failure mode of deep hard rock.

[0096] Based on the crack types, crack failure angles and failure modes of the deep hard rock, representative areas are selected from the failure surface of the deep hard rock, and slices are taken from the failure surface based on the selected representative areas. The slices are scanned by SEM electron microscope to observe and record the microscopic features of the failure surface. Based on the microscopic features of the failure surface, it is judged that the failure mode of the deep hard rock at a microscopic angle is one of shear failure, tension failure or mixed failure.

[0097] In this embodiment, the most representative areas are selected by combining macroscopic and microscopic characteristics, taking into account factors such as crack type, failure angle, failure mode, and stress concentration. For example, areas with high crack density, failure angles consistent with principal stresses, and well-developed microcracks are selected. Slices removed from the failure surface are scanned by an SEM electron microscope. Based on the microscopic results obtained from the scans, information such as intergranular or transgranular failure, as well as scratches and tear edges on the crystal surface, can be observed. This information is used to further analyze the failure mode of deep hard rock from a microscopic perspective, namely, to determine whether the rock failure mode is tensile, shear, or mixed, and to corroborate with the macroscopic three-dimensional laser scanning results.

[0098] The failure mode of the deep hard rock at a macroscopic perspective is compared with the failure mode of the deep hard rock at a microscopic perspective to see if they are consistent. If they are consistent, the failure mode of the deep hard rock is determined; if they are inconsistent, the failure mode of the deep hard rock is re-judged based on the JRC value of the failure surface and the microscopic characteristics of the failure surface.

[0099] Then, by comparing the failure modes of deep hard rock after true triaxial tests without dynamic disturbance and the failure modes of deep hard rock after true triaxial tests under all dynamic disturbances, the failure modes of deep hard rock under different dynamic disturbances are determined.

[0100] Based on the full-process experimental data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed.

[0101] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, the specific contents of constructing the mechanical model of deep hard rock under dynamic disturbance true triaxial conditions are as follows:

[0102] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure mode of deep hard rock under different dynamic disturbances, the peak strength of deep hard rock under different dynamic disturbance conditions is obtained. The changing rules of the rock mass and the deformation of deep hard rock at each disturbance stage under different dynamic disturbance conditions are analyzed.

[0103] In this embodiment, different stresses are obtained based on the true triaxial test of deep hard rock dynamic disturbance. 、 And the deformation of hard rock samples at each disturbance stage under different disturbance frequencies f and different disturbance amplitudes A Peak strength of hard rock specimens under different disturbance conditions Laws of change.

[0104] According to the total stress-strain curve of deep hard rock under dynamic disturbance, the mechanical behavior of deep hard rock under dynamic disturbance is divided into three disturbance stages: elastic deformation stage, plastic deformation stage and irreversible deformation stage.

[0105] In this embodiment, at the initial stage of loading, the hard rock exhibits elastic behavior, with stress proportional to strain, following Hooke's law. At this point, the deep hard rock is in the elastic deformation stage. When the stress exceeds the yield strength of the deep hard rock, the deep hard rock enters the plastic stage, where strain continues to increase, but the stress no longer increases significantly. When the stress reaches the peak strength of the deep hard rock, the deep hard rock begins to break, forming macrocracks, and the deep hard rock enters the irreversible deformation stage. The peak strength point is the highest point on the stress-strain curve.

[0106] Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the elastic deformation, plastic deformation and irreversible deformation under dynamic disturbance are calculated respectively.

[0107] In this embodiment, since the irreversible deformation of deep hard rock under no dynamic disturbance should theoretically be zero, the irreversible strain caused by pure disturbance is extracted by comparing the difference in plastic strain under no dynamic disturbance and under dynamic disturbance.

[0108] According to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed.

[0109] The method for constructing the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is as follows:

[0110] Based on the elastic-plastic constitutive model, the incremental stress-strain relationship of deep hard rock is established according to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance.

[0111] (1);

[0112] (2);

[0113] (3);

[0114] (4);

[0115] in represents the total strain of deep hard rock; Represents the elastic strain of deep hard rock; Represents the plastic strain of deep hard rock; It represents the irreversible strain of deep hard rock caused by dynamic disturbance; Indicates the true stress of deep hard rock; represents the plastic damage coefficient; represents the dynamic disturbance damage coefficient, which is the same as the dynamic disturbance influence factor D established later; It represents the effective stress of deep hard rock; is the disturbance period; is the number of disturbances; is the disturbance time.

[0116] The effective stress of deep hard rock and the true stress of deep hard rock Expressed as:

[0117] (5);

[0118] (6);

[0119] in represents the elastic modulus; Plastic history variables representing the final residual state; represents the plastic history at a certain moment; The historical variables representing the irreversible deformation of the dynamic disturbance; Represents the irreversible deformation history of the dynamic disturbance at a certain moment.

[0120] The stress-strain relationship of the deep hard rock incremental form is expressed as:

[0121] (7);

[0122] (8);

[0123] in represents the stress increment tensor; represents the strain increment tensor; Based on Young's modulus , Poisson's ratio and plastic history Anisotropic elastic stiffness tensor of; plastic history As an internal variable, it represents the inelastic irreversible deformation according to the second law of thermodynamics; is the irrecoverable strain increment of the dynamic disturbance; represents the plastic strain increment; Indicates brittleness index.

[0124] According to the plastic flow law, the plastic strain increment of deep hard rock under dynamic disturbance true triaxial conditions is determined , expressed as:

[0125] (9);

[0126] (10);

[0127] (11);

[0128] (12);

[0129] in Indicates violation of the criterion; Represents the failure criterion and the true stress of deep hard rock and the parameters related to the failure criterion association; represents the plasticity increment factor; Relevant parameters representing the failure criterion and plastic history association; is the plastic potential function, and the non-associated flow law is adopted, that is, ; Represents the plastic potential function and the true stress of deep hard rock and related parameters of the plastic potential function association; Related parameters representing the plastic potential function and plastic history association; To expand the angle, this embodiment changes the internal friction angle As an expansion angle.

[0130] Plastic potential function In the three-dimensional principal stress space, it is represented as a curved surface, namely the three-dimensional surface of plastic potential, and the expansion angle To control the shape of the three-dimensional surface of the plastic potential, the plastic potential function is expressed as:

[0131] (13);

[0132] (14);

[0133] (15);

[0134] (16);

[0135] (17);

[0136] in represents the first invariant of the stress tensor; Indicates uniaxial tensile strength; according to and The plastic potential function is divided into two parts by the relationship Serves as the separation boundary between the tensile and shear zones; It indicates the shear-dominant zone, where deep hard rock is mainly damaged by shear slip; Indicates the tensile zone, where deep hard rock is dominated by tensile faults; represents the second invariant of the deviatoric stress tensor; is the expansion angle correction factor, which indicates the degree of volume expansion during plastic flow; is the shear strength correction factor; It indicates cohesion; With lode angle correlation, used to describe the differences in shear response under different stress states; is the stress tensor transformation function, which represents the transverse size of the plastic surface in the tensile zone; It is a function related to the stress tensor and controls the position of the plastic surface in the tensile zone.

[0137] Determination of irrecoverable strain increment of deep hard rock under dynamic perturbation true triaxial conditions , expressed as:

[0138] (18);

[0139] in In order to consider the average strain fitting generated by a single disturbance under different stress states and different amplitude disturbances; is the dynamic disturbance multiplier, which increases with the number of disturbances, resulting in an increase in the strain rate of the irrecoverable strain caused by the disturbance.

[0140] Then, based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the dynamic disturbance damage factor is determined and expressed as:

[0141] (19);

[0142] (20);

[0143] in is the dynamic disturbance damage factor; and These are all material parameters obtained from the full-process test data of mechanical behavior of deep hard rock under dynamic disturbance. It represents the critical stress of dynamic disturbance, which is obtained by the inflection points of deformation rate in the three principal stress directions in the test data.

[0144] In this implementation, the dynamic perturbation damage factor is expressed as a function consisting of the perturbation amplitude and frequency under true triaxial dynamic perturbation. By analyzing the acquired test data, the elastic and plastic deformations of deep hard rock during each stage of the perturbation, as well as the irreversible deformation of the perturbation, are determined. This allows the construction of a mechanical model of hard rock under true triaxial dynamic perturbation.

[0145] Determine the cohesion based on the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance and internal friction angle Parameter evolution model under true triaxial conditions of dynamic disturbance.

[0146] In this embodiment, based on the experimental data of deep hard rock under dynamic disturbance true triaxial conditions, a mechanical model is established, internal variables are determined, and the evolution law of cohesion c and internal friction angle φ during the entire deformation and fracture process is obtained, as shown in the following example: Figure 6 shown.

[0147] The mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is used to determine the cohesion and internal friction angle The specific content of the parameter evolution model under the true triaxial condition of dynamic disturbance is:

[0148] Based on the full process test data of mechanical behavior of deep hard rock under dynamic disturbance, the initial cohesion is solved and initial internal friction angle , residual cohesion and residual internal friction angle .

[0149] Combined initial cohesion and initial internal friction angle , residual cohesion , residual internal friction angle and dynamic disturbance damage factors, building cohesion and internal friction angle The parameter evolution model under true triaxial conditions of dynamic disturbance is expressed as:

[0150] (twenty one);

[0151] (twenty two);

[0152] (twenty three);

[0153] (twenty four);

[0154] (25);

[0155] in Indicates the The increment of internal variables in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; is a positive operator, expressed as: ; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the present invention.

Claims

1. A method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance, characterized in that: The method includes the following steps: Conduct true triaxial tests on deep hard rock samples taken from deep tunnel projects without dynamic disturbance, and record the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance; Based on the full-process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, true triaxial tests were carried out on deep hard rock taken from deep tunnel projects under dynamic disturbance, and the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance were recorded; For deep hard rock after true triaxial test without dynamic disturbance and deep hard rock after true triaxial test with dynamic disturbance, the failure mode of deep hard rock after each test is determined by comparing and analyzing the failure mode of deep hard rock under different dynamic disturbances; Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed. Determine the cohesion based on the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance and internal friction angle Parameter evolution model under true triaxial conditions of dynamic disturbance.

2. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 1, characterized in that: The specific contents of the true triaxial test on deep hard rock taken from deep tunnel engineering without dynamic disturbance and recording the full process test data of the mechanical behavior of deep hard rock under the non-dynamic disturbance are as follows: For deep tunnel projects, obtain surrounding rock stress data at different distances from the tunnel face; The surrounding rock stress data include: intermediate principal stress and minimum principal stress ; The stress path is designed based on all the surrounding rock stress data obtained, and according to the designed stress path, a true triaxial test without dynamic disturbance is carried out on the deep hard rock using a dynamic disturbance true triaxial testing machine to obtain the peak strength of the deep hard rock under no dynamic disturbance. , and record the full process test data of the mechanical behavior of deep hard rock under no dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under no dynamic disturbance; The full-process test data of the mechanical behavior of deep hard rock under true triaxial action are: stress values ​​and strain values ​​of deep hard rock in three directions under principal stress changes.

3. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 2, characterized in that: The deep hard rocks used in the hard rock true triaxial stress path test and the deep hard rock dynamic perturbation true triaxial test are all standard rock samples cut from the same rock, and all standard rock samples pass the homogeneity test before the test.

4. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 3, characterized in that: The specific method for conducting true triaxial tests under dynamic disturbance on deep hard rock taken from a deep tunnel project based on the full-process test data on the mechanical behavior of deep hard rock under no dynamic disturbance, and recording the full-process test data on the mechanical behavior of deep hard rock under dynamic disturbance, is as follows: According to the peak strength of deep hard rock under no dynamic disturbance Set several different disturbance times; Obtain the disturbance wave signal at the tunnel engineering site and generate a disturbance wave time-frequency curve. Extract the frequency range of the disturbance wave from the disturbance wave time-frequency curve. Then, based on the disturbance wave signal at the tunnel engineering site and the frequency range of the disturbance wave, determine several disturbance frequencies through Fourier transform. ; Obtain rock wave velocity, rock density and surrounding rock particle velocity at the tunnel engineering site, and calculate several disturbance amplitudes using the measured rock wave velocity, rock density and surrounding rock particle velocity ; By traversing all perturbation frequencies and the disturbance amplitude to generate all possible dynamic disturbance conditions; Based on the stress path designed in the true triaxial test without dynamic disturbance, the true triaxial test under dynamic disturbance is carried out on the deep hard rock according to different dynamic disturbance conditions. During the test, dynamic disturbance is applied according to several set disturbance timings to obtain the peak strength of the deep hard rock under dynamic disturbance. , and record the full process test data of the mechanical behavior of deep hard rock under dynamic disturbance, and then draw the full stress-strain curve of deep hard rock under dynamic disturbance; The full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance include: disturbance time, number of disturbances, strength value, stress value and strain value of deep hard rock under dynamic disturbance.

5. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 4, characterized in that: The specific content of determining the failure mode of deep hard rock under different dynamic disturbances by comparing and analyzing the failure modes of deep hard rock after true triaxial tests without dynamic disturbance and deep hard rock under true triaxial tests with dynamic disturbance is as follows: For any deep hard rock after a true triaxial test without dynamic disturbance or after a true triaxial test under dynamic disturbance, determine the type of crack in the deep hard rock and measure the crack failure angle of the deep hard rock; Perform 3D laser scanning on the failure surface of the deep hard rock to obtain the horizontal coordinates of each point on the failure surface. The JRC value of the failure surface is calculated using the horizontal coordinates of each point. Based on the JRC value of the failure surface, it is determined that the failure mode of the deep hard rock from a macro perspective is shear failure, tension failure, or mixed failure. Based on the crack type, crack failure angle, and failure mode of the deep hard rock, a representative area is selected from the failure surface of the deep hard rock, and a slice is taken from the failure surface based on the selected representative area. The slice is scanned by an SEM electron microscope to observe and record the microscopic features of the failure surface. Based on the microscopic features of the failure surface, the failure mode of the deep hard rock at a microscopic angle is determined to be shear failure, tension failure, or mixed failure. Compare the failure modes of the deep hard rock at a macroscopic perspective and the failure modes of the deep hard rock at a microscopic perspective to see if they are consistent. If they are consistent, determine the failure mode of the deep hard rock. If they are inconsistent, re-evaluate the failure mode of the deep hard rock based on the JRC value of the failure surface and the microscopic characteristics of the failure surface. Then, by comparing the failure modes of deep hard rock after true triaxial tests without dynamic disturbance and the failure modes of deep hard rock after true triaxial tests under all dynamic disturbances, the failure modes of deep hard rock under different dynamic disturbances are determined.

6. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 5, characterized in that: Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure modes of deep hard rock under different dynamic disturbances, the specific contents of constructing the mechanical model of deep hard rock under dynamic disturbance true triaxial conditions are as follows: Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance and the failure mode of deep hard rock under different dynamic disturbances, the peak strength of deep hard rock under different dynamic disturbance conditions is obtained. The changing rules of the rock mass and the deformation of deep hard rock at each disturbance stage under different dynamic disturbance conditions; According to the full stress-strain curve of deep hard rock under dynamic disturbance, the mechanical behavior of deep hard rock under dynamic disturbance is divided into three disturbance stages: elastic deformation stage, plastic deformation stage and irreversible deformation stage. Based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the elastic deformation, plastic deformation and irreversible deformation under dynamic disturbance are calculated respectively. According to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance, a mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is constructed.

7. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 6, characterized in that: The method for constructing the mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is as follows: Based on the elastic-plastic constitutive model, the incremental stress-strain relationship of deep hard rock is established according to the elastic deformation, plastic deformation and irreversible deformation of deep hard rock under dynamic disturbance, which can be expressed as: ； ； in represents the stress increment tensor; represents the strain increment tensor; Based on Young's modulus , Poisson's ratio and plastic history Anisotropic elastic stiffness tensor of; plastic history As an internal variable, it represents the inelastic irreversible deformation according to the second law of thermodynamics; is the irrecoverable strain increment of deep hard rock under true triaxial dynamic disturbance conditions; represents the plastic strain increment; Indicates brittleness index; For the incremental stress-strain relationship of deep hard rock, the plastic strain increment of deep hard rock under dynamic perturbation true triaxial conditions is determined according to the plastic flow law. At the same time, the irrecoverable strain increment of deep hard rock under dynamic disturbance true triaxial conditions is determined ; Then, based on the full-process test data of the mechanical behavior of deep hard rock under dynamic disturbance, the dynamic disturbance damage factor is determined.

8. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 7, characterized in that: The irrecoverable strain increment of the deep hard rock under the dynamic disturbance true triaxial condition , expressed as: ； in In order to consider the average strain fitting generated by a single disturbance for different amplitude disturbances under different stress states; is the dynamic disturbance multiplier; is the disturbance time.

9. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 8, characterized in that: The dynamic disturbance damage factor is: ； in is the dynamic disturbance damage factor; and These are all material parameters obtained from the full-process test data of mechanical behavior of deep hard rock under dynamic disturbance. represents the critical stress of dynamic disturbance; is the number of disturbances.

10. The method for establishing a three-dimensional mechanical model of deep hard rock dynamic disturbance according to claim 9, characterized in that: The mechanical model of deep hard rock under true triaxial conditions of dynamic disturbance is used to determine the cohesion and internal friction angle The specific content of the parameter evolution model under the true triaxial condition of dynamic disturbance is: Based on the full process test data of mechanical behavior of deep hard rock under dynamic disturbance, the initial cohesion is solved and initial internal friction angle , residual cohesion and residual internal friction angle ; Combined initial cohesion and initial internal friction angle , residual cohesion , residual internal friction angle and dynamic disturbance damage factors, building cohesion and internal friction angle The parameter evolution model under true triaxial conditions of dynamic disturbance is expressed as: ； ； ； ； ； in Indicates the The increment of internal variables in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; Indicates the The final value of the internal variable in each deformation stage; is the positive operator; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The reduction ratio of cohesion in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage; Indicates the The enhancement ratio of the internal friction angle in each deformation stage.

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