A method for quantitatively evaluating rock mass quality characteristics based on the energy dissipation coefficient of engineering rock mass

Abstract

This invention relates to a method for quantitatively assessing the quality characteristics of engineering rock masses based on their energy dissipation coefficient. The method involves conducting in-situ deformation tests on rigid bearing plates of the rock mass at the engineering site, and obtaining pressure-deformation curves of the rock mass through graded loading. Based on the type of pressure-deformation curve, the quality characteristics of the rock mass are initially classified. Graphical integration is performed on the pressure-deformation curves to calculate the input energy, elastic energy, and dissipated energy during the loading process. The energy storage and energy dissipation coefficients of the rock mass are obtained by fitting the curves and applying linear energy storage laws. Finally, the quality characteristics of the rock mass are quantitatively assessed based on its energy dissipation coefficient. This invention quantitatively assesses the quality characteristics of engineering rock masses from an energy perspective based on their energy dissipation coefficient, overcoming the inaccuracy of qualitative empirical methods such as rigid bearing plate curve types in identifying rock mass quality characteristics. It provides an effective reference for the stability assessment and support design of engineering rock masses and possesses significant innovation, practicality, economy, and feasibility.

Description

Technical Field

[0001] This invention relates to a method for quantitatively evaluating the quality characteristics of rock mass based on the energy dissipation coefficient of engineering rock mass, which belongs to the field of engineering rock mass quality assessment. Background Technology

[0002] The assessment of rock mass quality is crucial for the construction and design of rock mass engineering projects. In-situ deformation tests are necessary during construction to obtain information about the rock mass. Rigid bearing plate deformation tests are the most commonly used in-situ rock mass deformation testing method both domestically and internationally due to their ease of meeting stiffness and uniform vertical deformation distribution under pressure, and their applicability to both soft and hard rock masses. Furthermore, through long-term practice, numerous scholars and testing personnel have made significant contributions to the interpretation of rigid bearing plate deformation test results and the improvement of testing methods, making it a theoretically sound, well-defined, technically mature rock mass testing and assessment method whose results can serve as a fundamental basis for value determination.

[0003] However, when dealing with engineering rock masses with complex structural surfaces, qualitatively assessing the rock mass quality characteristics based solely on the type of pressure-deformation curve can be inaccurate. In fact, the pressure-deformation curve type only reflects the deformation elements of the rock mass under external force, without considering the changes in internal stress during loading. Rock masses of different qualities exhibit different macroscopic deformation and internal stress changes during loading, thus judging rock mass quality solely based on the pressure-deformation curve type has limitations. According to the first law of thermodynamics, the internal energy of engineering rock masses undergoes transformation during in-situ rigid pressure plate deformation testing. Since energy integrates both stress and deformation factors, assessing the quality characteristics of rock masses based on their energy transformation characteristics during loading can overcome the incompleteness of conventional assessment methods. Previous patent CN201711209289.8 has already demonstrated the linear energy storage and dissipation laws of rock materials under compression, and pointed out that the energy storage coefficient and energy dissipation coefficient are two quantitative indicators for evaluating the energy storage and dissipation characteristics of materials during loading. In fact, at the rock mass scale, rock masses also conform to linear energy storage and dissipation laws. However, there are differences between rock masses and rocks in terms of energy storage and dissipation coefficients. In rock materials, the energy storage coefficient is dominant, while in rock masses, the energy dissipation coefficient is dominant. Therefore, in assessing the quality characteristics of rock masses, it is necessary to propose a method for quantitatively evaluating the quality characteristics of engineering rock masses based on the energy dissipation coefficient, in order to overcome the inaccuracies of traditional methods and provide an effective reference for the assessment of engineering stability and support design. Summary of the Invention

[0004] This invention provides a method for quantitatively evaluating the quality characteristics of rock masses based on the energy dissipation coefficient of engineering rock masses. It aims to quantitatively evaluate the quality characteristics of rock masses from an energy perspective by using the energy dissipation coefficient of the rock mass, thereby solving the problem of insufficient accuracy in qualitatively identifying the quality characteristics of rock masses based on the pressure-curve type of rigid bearing plates.

[0005] The present invention adopts the following solution:

[0006] A method for quantitatively evaluating the quality characteristics of engineering rock masses based on the energy dissipation coefficient, the specific steps of which are as follows:

[0007] Step S1: Conduct in-situ deformation tests of the rigid bearing plate of the rock mass at the engineering site;

[0008] Step S2: Obtain the pressure-deformation curve of the engineering rock mass through the in-situ deformation test and graded loading in step S1;

[0009] Step S3: Based on the pressure-deformation curve of the engineering rock mass obtained in step S2, make a preliminary assessment of the quality characteristics of the rock mass;

[0010] Step S4: Integrate the pressure-deformation curve of the engineering rock mass and calculate the input energy, elastic energy, and dissipated energy during the loading process of the rock mass.

[0011] Step S5: Fit the input energy, elastic energy, and dissipated energy from step S4, and obtain the energy storage coefficient and energy dissipation coefficient of the rock mass according to the linear energy storage law;

[0012] Step S6: Quantitatively evaluate the quality characteristics of the rock mass by combining the energy dissipation coefficient of the engineering rock mass with the pressure-deformation curve of the engineering rock mass obtained in step S3.

[0013] The method for quantitatively evaluating the quality characteristics of rock mass based on the energy dissipation coefficient of engineering rock mass, as described in this invention, involves step S1, the rigid bearing plate deformation test. The principle of this step is based on the assumption that the plane containing the bearing platform is an infinite plane, and the semi-infinite bedrock beneath the bearing platform is a homogeneous isotropic elastic medium. The basic parameters of the rigid bearing plate can be found in the "Code for Rock Testing in Hydraulic and Hydropower Engineering" (SL / T264-2020). The diameter of the bearing plate is 50.5 mm, and the area is 2000 cm². 2 .

[0014] The method for quantitatively evaluating the quality characteristics of rock mass based on the energy consumption coefficient of engineering rock mass according to the present invention, wherein step S1, the in-situ test of the rigid bearing plate of the rock mass, is as follows: First, according to the geological characteristics of the engineering rock mass, a roughly flat rock surface with a range of 1m is selected as the test point, and a circular surface with a diameter of 60cm is ground with a grinding wheel; then, cement slurry containing an early strength agent is evenly applied to the polished circular surface, and a pressure plate, a force transmission system (jack), a measuring system (dial gauge), etc. are installed; finally, according to the actual characteristics of the engineering rock mass, the range of applied load and stress is set, and loading and unloading are carried out in 5 stages; the reading is taken immediately after loading or unloading, and then every 10 minutes thereafter.

[0015] The method for quantitatively evaluating the quality characteristics of engineering rock mass based on the energy dissipation coefficient of the rock mass described in this invention, in step S3, involves testing the deformation of rigid bearing plates in engineering rock masses. Different engineering rock masses typically exhibit three types of pressure-deformation curves: linear, concave, and convex. In practice, it has been found that the linear curve mainly reflects a complete, hard, dense rock mass with few fissures, closely resembling a homogeneous elastic body. Within the test pressure range, the rock mass exhibits the deformation characteristics of a homogeneous body, with deformation showing a linear relationship with pressure. The concave curve mainly reflects the characteristics of a heterogeneous rock mass with bedding, fissures, and other structural surfaces that are not uniformly distributed along the pressure direction. During the test, as the pressure increases, the structural surfaces are gradually compacted, and the stiffness and modulus increase. The convex curve mainly reflects a rock mass with bedding and fissures, with the fissures becoming denser and the stiffness decreasing with increasing depth. During the test, due to the presence of weak interlayers at a certain depth below the bearing plate, the depth of influence increases with increasing load, leading to accelerated deformation. Based on the type of pressure-deformation curve, linear, concave-top, and concave-bottom curves are respectively classified as high, medium, and low rock mass quality grades.

[0016] The method for quantitatively evaluating the quality characteristics of rock mass based on the energy consumption coefficient of engineering rock mass described in this invention, in step S4, according to the first law of thermodynamics, assuming that no heat exchange occurs between the rock mass and the external environment during the in-situ loading and deformation process of the rigid bearing plate, can be regarded as a closed-loop system. The work done by the rigid bearing plate during loading can be used as the input energy of rock mass deformation. The specific energy conversion can be expressed as equation (1):

[0017] U a =U e +U d (1)

[0018] In formula (1), U a U e and U d These represent input energy, elastic energy, and dissipated energy, respectively. U e U represents the stored elastic energy of the rock mass during loading. dThis represents the energy dissipated by the rock mass during loading, causing irreversible plastic deformation and internal damage to the rock mass.

[0019] Since the rigid bearing plate method uses a graded cyclic loading method, the graphical area integration method can be used to calculate the input energy U of the rock mass. a Elasticity U e and dissipated energy U d Simultaneously, the input energy calculation selects the outer envelope of the loading and unloading curve for calculation. The specific calculation method for rock mass energy can be expressed as equation (2):

[0020]

[0021] In formula (2), f o (w) is the outer envelope of the loading curve; f u (w) represents the unloading curve; w n The deformation at the nth loading point (n = 1, 2, ..., 5) is in mm; w j The deformation at the j-th unloading point (j=1,2,…,5), mm.

[0022] The method for quantitatively evaluating the quality characteristics of rock mass based on the energy dissipation coefficient of engineering rock mass according to the present invention, in step S5, calculates the elastic energy U of the rock mass. e Dissipated energy U d With input energy U a Linear fitting was performed between the two, confirming that it conforms to the linear energy storage and energy consumption law of engineering rock mass, which can be specifically expressed as equation (3):

[0023]

[0024] In formula (3), a and c represent the energy storage coefficient and energy dissipation coefficient of the rock mass, respectively. The energy storage coefficient a represents the ability of the rock mass to store elastic energy during loading and deformation; conversely, the energy dissipation coefficient c represents the energy dissipation capacity of the rock mass during loading and deformation, where c = 1 - a; b is the fitting parameter.

[0025] Furthermore, in step S6, the larger the energy dissipation coefficient c of the engineering rock mass, the worse the quality characteristics of the rock mass; conversely, the smaller the energy dissipation coefficient c of the engineering rock mass, the better the quality characteristics of the rock mass. Simultaneously, based on the statistical analysis of the engineering rock mass quality characteristics corresponding to different energy dissipation coefficients, standards for evaluating rock mass quality are defined using the engineering rock mass energy dissipation coefficient, as shown in expression (4):

[0026]

[0027] By employing the above technical solutions, the present invention has the following beneficial effects compared to the prior art:

[0028] 1. This invention provides a method for quantitatively assessing the quality characteristics of engineering rock masses based on their energy dissipation coefficients. The method involves obtaining the pressure-deformation curve of the engineering rock mass through deformation tests using a rigid bearing plate. Based on the type of this pressure-deformation curve, the quality characteristics of the rock mass are initially qualitatively assessed. Furthermore, the pressure-deformation curve is integrated to calculate the input energy, elastic energy, and dissipated energy during the rock mass loading process. The elastic energy, dissipated energy, and input energy are fitted together to demonstrate the linear energy storage and dissipation laws of the engineering rock mass. Based on this, the energy storage coefficient and energy dissipation coefficient of the engineering rock mass are obtained. In other words, from an energy perspective, the method uses the energy dissipation coefficient of the engineering rock mass to quantitatively assess its quality characteristics, thus addressing the inaccuracy of qualitative assessments of engineering rock mass characteristics using rigid bearing plate pressure-deformation curves. This provides an effective reference for the stability assessment and engineering design of engineering rock masses and is highly innovative.

[0029] 2. The method for quantitatively evaluating the quality characteristics of engineering rock mass based on the energy dissipation coefficient of the engineering rock mass provided by the present invention analyzes the energy evolution characteristics of the rock mass based on the deformation test of the rigid bearing plate of the engineering rock mass and the pressure-deformation curve of the rigid bearing plate, and obtains the energy dissipation coefficient of the engineering rock mass to evaluate the quality characteristics of the engineering rock mass. That is, the quality characteristics of the rock mass can be evaluated without adding extra workload to the engineering site, which has strong economy, feasibility and practicality. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the method for quantitatively evaluating rock mass quality characteristics based on the energy dissipation coefficient of engineering rock mass according to the present invention.

[0031] Figure 2 This is a schematic diagram of in-situ deformation testing of rigid bearing plates in engineering rock mass.

[0032] Figure 3 A schematic diagram of the pressure-deformation curve (linear type) for testing rigid bearing plates in engineering rock masses;

[0033] Figure 4 This is a schematic diagram of the pressure-deformation curve (concave type) for testing rigid bearing plates in engineering rock masses.

[0034] Figure 5 This is a schematic diagram of the pressure-deformation curve (concave type) for testing rigid bearing plates in engineering rock masses.

[0035] Figure 6 A schematic diagram for inputting energy calculations during the compression process of engineering rock mass;

[0036] Figure 7 A schematic diagram for calculating the elastic energy and dissipated energy during the compression process of engineering rock mass;

[0037] Figure 8This is a linear curve type used in the deformation test of the rigid bearing plate at the slope dam site of a certain water conservancy project.

[0038] Figure 9 The concave curve type is used in the deformation test of the rigid bearing plate at the slope dam site of a certain water conservancy project.

[0039] Figure 10 This is a concave curve type used in the deformation test of the rigid bearing plate at the slope dam site of a certain water conservancy project.

[0040] Figure 11 The linear curve type is used for in-situ rock mass deformation test of the rigid bearing plate of an underground powerhouse of a hydropower station.

[0041] Figure 12 The concave (I) curve type is used for in-situ rock mass deformation test of the rigid bearing plate of an underground powerhouse of a hydropower station.

[0042] Figure 13 This is a concave (II) curve type for in-situ rock mass deformation testing of the rigid bearing plate of an underground powerhouse of a hydropower station.

[0043] In the diagram, 1 is the transmission column, 2 is the steel plate, 3 is the jack, 4 is the dial indicator, and 5 is the rigid pressure plate. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] As attached Figure 1 As shown, a method for quantitatively evaluating the quality characteristics of rock mass based on the energy dissipation coefficient of engineering rock mass is described below.

[0046] (1): Rigid bearing plate tests were conducted on-site in the rock mass engineering project. Based on the geological characteristics of the engineering rock mass, a roughly flat rock surface with a range of 1m was selected as the test point. A circular surface with a diameter of 60cm was ground using a grinding wheel. Then, cement slurry containing an early-strength agent was evenly applied to the polished circular surface, and the pressure plate, force transmission system, and measuring system were installed. The diameter of the rigid bearing plate was 50.5mm, and the area was 2000cm². 2 Finally, based on the actual characteristics of the rock mass, the range of applied loads and stresses was set, and loading and unloading were performed in five stages in a cyclical manner. Data was read immediately after loading or unloading, and then every 10 minutes thereafter.

[0047] (2): Based on the test of the deformation of the rigid bearing plate of the engineering rock mass, identify the type of the pressure-deformation curve of the engineering rock mass, and preliminarily judge the quality characteristics of the rock mass. If it is a straight line type, the engineering rock mass at this measuring point is complete, hard, dense, and has few fissures, and is relatively close to a homogeneous elastic body, with good quality grade. If it is a concave-up type, the engineering rock mass at this measuring point has the characteristics of a heterogeneous rock mass with bedding, fissures and other structural planes and non-uniform distribution along the pressurization direction, and the quality grade is average. If it is a concave-down type, the engineering rock mass at this measuring point is a rock mass with bedding and fissures, and has the characteristics that the fissures of the rock mass are densified and the stiffness is weakened with the increase of depth, and the quality grade is poor.

[0048] (3): According to the pressure-deformation curve of the engineering rock mass obtained from the test of the deformation of the rigid bearing plate, further adopt the graphical area integration method to calculate the input energy U of the engineering rock mass a , elastic energy U e and dissipated energy U d . By fitting the elastic energy U e , dissipated energy U d and input energy U a at different stress levels, obtain the expressions of the specific linear energy storage and energy dissipation laws of the engineering rock mass, and based on this, obtain the energy storage coefficient and energy dissipation coefficient of the engineering rock mass.

[0049] (4): Based on the energy dissipation coefficient of the engineering rock mass, evaluate the quality characteristics of the engineering rock mass. The specific grading standard can be expressed as: when 0 < c < 0.55, the quality characteristics of the rock mass are at a high level; when 0 < c < 0.55, the quality characteristic level of the rock mass is high; when 0.55 < c ≤ 0.55, the quality characteristic level of the rock mass is medium; when 0.76 < c < 1, the quality characteristic level of the rock mass is low. Quantitatively evaluate the quality characteristics of the rock mass through the energy dissipation coefficient of the engineering rock mass.

[0050] Example 1

[0051] Taking the in-situ rock mass deformation test of the rigid bearing plate of a certain water conservancy project slope dam site as an example, judge the quality characteristics of the dam site rock mass. First, obtain the pressure-deformation curve of the rigid bearing plate of the engineering rock mass, preliminarily evaluate the quality characteristics of the rock mass at the measuring point according to the curve type, and then continue to further integrate the pressure-deformation curve of the rigid bearing plate of the engineering rock mass to obtain the energy parameters, and then obtain the energy storage coefficient and energy dissipation coefficient of the engineering rock mass through the linear energy storage law of the rock mass, and then further evaluate the quality characteristics of the engineering rock mass, as follows:

[0052] (1): According to the "Specifications for Rock Testing in Water Conservancy and Hydropower Engineering" (SL / T264-2020), a roughly flat rock surface with a range of 1m was selected as the test point. A circular surface with a diameter of 60cm was ground using a grinding wheel. Then, cement slurry containing an early-strength agent was evenly applied to the polished circular surface, and a pressure plate, force transmission system, and measuring system were installed. The rigid pressure plate has a diameter of 50.5mm and an area of ​​2000cm². 2 Finally, based on the actual characteristics of the rock mass and the design data, the maximum applied load for the test was set to 2–4 MPa, and the load was cyclically applied and unloaded in 5 stages. Data was read immediately after loading or unloading, and then every 10 minutes thereafter.

[0053] (2): Based on the deformation test of the rigid bearing plate of the engineering rock mass, the pressure-deformation curve type of the engineering rock mass was identified, and the quality characteristics of the rock mass were preliminarily judged. The pressure-deformation curve types of this engineering rock mass are mainly divided into three categories: linear, concave upward, and concave downward, as detailed in the appendix. Figure 8 , Figure 9 and Figure 10 Preliminary assessment indicates that the rock mass at the straight-line measuring point is a complete, hard, and dense rock mass with a high quality grade; the rock mass at the concave-shaped measuring point is a layered, fractured, heterogeneous rock mass with a medium quality grade; and the rock mass at the drooping-shaped measuring point is a layered, fractured, and dense heterogeneous rock mass with a low quality grade.

[0054] (3): Based on the pressure-deformation curve of the engineering rock mass obtained from the rigid bearing plate deformation test, the input energy U of the engineering rock mass is further calculated using the graphical area integration method. a Elasticity U e and dissipated energy U d By fitting the elastic energy U under different stress levels e Dissipated energy U d With input energy U a The expressions for the specific linear energy storage and dissipation laws of the engineering rock mass are obtained, and based on these, the energy storage coefficient and energy dissipation coefficient of the engineering rock mass are derived. The input energy U for the engineering rock mass is calculated. a Elasticity U e and dissipated energy U d As shown in Table 1.

[0055] (4): The quality characteristics of the engineering rock mass were further quantitatively assessed based on its energy dissipation coefficient. The energy dissipation coefficient of the rigid bearing plate of the engineering rock mass was 0.5407, corresponding to a high quality level according to the evaluation standard; the energy dissipation coefficient of the concave curve was 0.5706, corresponding to a medium quality level; and the energy dissipation coefficient of the concave curve at the measuring point of the rigid bearing plate was 0.8204, corresponding to a low quality level. From the results of assessing the quality characteristics of the engineering rock mass based on its energy dissipation coefficient, the above results are basically consistent with the results of the qualitative assessment based on the curve type. However, the quality characteristics of the rock mass were further quantitatively assessed by calculating its energy dissipation coefficient.

[0056] Table 1. Calculation results of rock mass energy parameters, rock mass storage coefficient, and energy dissipation coefficient for a certain project.

[0057]

[0058] Example 2

[0059] Using the method of this invention, taking an in-situ rock mass deformation test of a rigid bearing plate in an underground powerhouse as an example, the quality characteristics of the engineering rock mass are evaluated. Specifically:

[0060] (1): According to the "Specifications for Rock Testing in Water Conservancy and Hydropower Engineering" (SL / T264-2020), a roughly flat rock surface with a range of 1m was selected as the test point. A circular surface with a diameter of 60cm was ground using a grinding wheel. Then, cement slurry containing an early-strength agent was evenly applied to the polished circular surface, and a pressure plate, force transmission system, and measuring system were installed. The rigid pressure plate has a diameter of 50.5mm and an area of ​​2000cm². 2 Finally, based on the actual characteristics of the rock mass and design data, the range of the maximum applied load for the test was set, and loading and unloading were performed in five stages. Data was read immediately after loading or unloading, and then every 10 minutes thereafter.

[0061] (2): Based on the deformation test of the rigid bearing plate of the engineering rock mass, identify the type of pressure-deformation curve of the engineering rock mass, and preliminarily assess the quality characteristics of the engineering rock mass. (Appendix) Figure 11 , Figure 12 and Figure 13 The study showcases representative pressure-deformation curve types for rock mass monitoring points in the underground powerhouse project, primarily linear, concave (I), and concave (II). These three curve types correspond to medium-thick, thick-layered hard rock masses, mixed hard and soft rock masses, and shear zones and weak interlayered rock masses, respectively. Based on the pressure-deformation curve types, the preliminary assessment classifies the rock mass corresponding to these three curve types as high quality (linear), medium quality (concave (I)), and medium quality (concave (II)).

[0062] (3): Based on the pressure-deformation curve of the engineering rock mass obtained from the rigid bearing plate deformation test, the input energy U of the engineering rock mass is further calculated using the graphical area integration method. a Elasticity U e and dissipated energy U d By fitting the elastic energy U under different stress levels e Dissipated energy U d With input energy U a The expressions for the specific linear energy storage and dissipation laws of the engineering rock mass are obtained, and based on this, the energy storage coefficient and energy dissipation coefficient of the engineering rock mass are obtained. The input energy U for the calculated engineering rock mass of this underground powerhouse is... a Elasticity U e and dissipated energy U d As shown in Table 2;

[0063] (4): The quality characteristics of the engineering rock mass are further quantitatively evaluated based on the energy dissipation coefficient of the engineering rock mass. The energy dissipation coefficient of the rigid bearing plate linear curve of the engineering rock mass is 0.3102 (linear), which means that the corresponding engineering rock mass quality grade is high; the energy dissipation coefficient of the rigid bearing plate concave (I) curve is 0.5633 (concave (I)), which means that the corresponding engineering rock mass quality grade is medium; the energy dissipation coefficient of the rigid bearing plate concave (II) curve is 0.8865 (concave (II)), which means that the corresponding engineering rock mass quality grade is low. Based on the energy dissipation coefficient calculated from the engineering rock mass, the concave (II) curve at the bearing plate measuring point indicates a low-grade rock mass quality. This result is inconsistent with the rock mass quality characteristics initially determined by the curve type. According to the actual rock mass characteristics, the engineering rock mass belongs to shear zone and weak interlayer rock mass, and its rock mass quality characteristics are low-grade. This is consistent with the results of the energy dissipation coefficient assessment. Therefore, by calculating the energy storage coefficient of the rock mass, the quality characteristics of the rock mass were further quantitatively assessed, making up for the inaccuracy of assessing the engineering rock mass characteristics by the rigid bearing plate pressure-deformation curve type.

[0064] Table 2. Calculation results of rock mass energy parameters, rock mass storage coefficient, and energy dissipation coefficient for an underground powerhouse project.

[0065]

[0066]

[0067] In summary, the method proposed in this application for quantitatively evaluating the quality characteristics of rock mass based on the energy storage and energy dissipation coefficient of engineering rock mass, on the basis of in-situ rock mass testing with rigid bearing plates, quantitatively evaluates the quality characteristics of rock mass from the perspective of overall energy by taking the energy dissipation coefficient of the rock mass. This solves the problem of insufficient accuracy in identifying rock mass quality characteristics by relying on the pressure-curve type of rigid bearing plates. At the same time, it is simple, efficient and does not need to consider the influence of too many other factors.

[0068] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein. The meaning of "and / or" as used herein includes both situations where each exists alone or both exist simultaneously.

[0069] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for quantitatively evaluating the quality characteristics of rock mass based on the energy dissipation coefficient of engineering rock mass, characterized in that, The specific steps are as follows: Step S1: Conduct an in-situ deformation test of a rigid bearing plate on the rock mass at the project site; Step S2: Obtain the pressure-deformation curve of the engineering rock mass through graded loading in the in-situ deformation test in Step S1; Step S3: Initially evaluate the quality characteristics of the rock mass based on the pressure-deformation curve of the engineering rock mass obtained in Step S2; Step S4: Integrate the pressure-deformation curve of the engineering rock mass to obtain the input energy, elastic energy, and dissipated energy during the loading process of the rock mass respectively; Based on the pressure-deformation curve of the engineering rock mass, the input energy of the engineering rock mass is calculated using the graphical area integral method. Elasticity and dissipated energy The specific integral expression is as follows: In the formula, The outer envelope of the loading curve; For unloading curves; Let n be the deformation at the nth loading point, where n = 1, 2, ..., 5, and the unit is mm. The deformation at the j-th unloading point, j=1, 2,…,5, is in mm; The work done by loading with a rigid bearing plate in the above formula is used as the input energy for the deformation of the rock mass. The specific energy conversion expression is as follows: Based on different pressure-deformation curves of engineering rock masses, elastic energy under different stress levels is fitted. Dissipated energy and input energy The specific linear energy storage and consumption laws of the engineering rock mass can be obtained through the following formula: In the formula, a and c Let b represent the energy storage coefficient and energy dissipation coefficient of the engineering rock mass, respectively; b is the fitting parameter; energy storage coefficient a The energy dissipation coefficient represents the rock mass's ability to store elastic properties during loading and deformation. c This represents the energy dissipation capacity of the rock mass during the loading and deformation process, where c =1- a ; Step S6: Fit the input energy, elastic energy, and dissipated energy in Step S4 and obtain the energy storage coefficient and energy dissipation coefficient of the rock mass according to the linear energy storage law; Step S6: Combine the energy dissipation coefficient of the engineering rock mass to quantitatively evaluate the quality characteristics of the engineering rock mass initially evaluated in Step S3 for the pressure-deformation curve of the engineering rock mass; 2. The method for quantitatively evaluating rock mass quality characteristics based on the energy dissipation coefficient of engineering rock mass according to claim 1, characterized in that: In the in-situ deformation test of the rigid bearing plate in Step S1, the plane where the bearing platform is located is set as an infinite plane, and the semi-infinite bedrock mass under the bearing platform is a homogeneous isotropic elastic medium; 3. The method for quantitatively evaluating rock mass quality characteristics based on the energy dissipation coefficient of engineering rock mass according to claim 1, characterized in that: The types of the pressure-deformation curve of the engineering rock mass in Step S3 include: linear type, concave-up type, and concave-down type; Linear type: The quality grade of the measured point engineering rock mass is high; If it is the concave-up type, the quality grade of the measured point engineering rock mass is medium; If it is the concave-down type, the quality grade of the measured point engineering rock mass is low; 4. The method for quantitatively evaluating rock mass quality characteristics based on the energy dissipation coefficient of engineering rock mass according to claim 1, characterized in that: The classification method in Step S6 is as follows: According to the quality characteristics of the engineering rock mass corresponding to different energy dissipation coefficients of the engineering rock mass, the grading standard is: When 0 < c < 0.55, the quality characteristic grade of the rock mass is high; When 0.55 < c7 ≤ 0.75, the quality characteristic grade of the rock mass is medium; When 0.76 < c < 1, the quality characteristic grade of the rock mass is low; 5. The method for quantitatively evaluating the quality characteristics of a rock mass based on the energy dissipation coefficient of an engineering rock mass according to claim 4, wherein: In Step S6: By comparing with the standard for quantitatively evaluating the quality characteristics of the rock mass based on the energy dissipation coefficient of the engineering rock mass, quantitatively evaluate the quality characteristics of the rock mass according to the energy storage coefficient of the engineering rock mass; Through the comparison between the result of quantitatively evaluating by the energy dissipation coefficient of the engineering rock mass and the type of the pressure-deformation curve tested by the rigid bearing plate, initially qualitatively identify the quality characteristics of the rock mass; Based on this comparison of the quality characteristics, compensate for the error in qualitatively evaluating the characteristics of the engineering rock mass by the type of the pressure-deformation curve of the rigid bearing plate.

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