Method for calculating deformation modulus of in-situ rock mass

Abstract

The invention relates to an in-situ rock mass deformation modulus calculation method, which comprises the following steps: based on a data set containing a rock name, an elastic longitudinal wave speed and a deformation modulus, in combination with a relationship between a dynamic elastic modulus and density, a Poisson's ratio and the longitudinal wave speed, through an interval number operation rule, obtaining a relationship between a rock mass dynamic / static modulus ratio and the deformation modulus; calculating the theoretical relationship between the longitudinal wave velocity and the dynamic elastic modulus, density and Poisson's ratio of the complete rock mass and the jointed rock mass, and calculating the normalized damage degree of the in-situ rock mass through a binary function operation rule according to the principle that the ratio of the dynamic elastic modulus to the static elastic modulus between the complete rock mass and the jointed rock mass is equal; and calculating the P-wave modulus of the complete rock mass, and correcting the P-wave modulus to obtain the deformation modulus of the in-situ rock mass. The method is based on theoretical derivation instead of a specific engineering data set, so that the method can be suitable for different types of rock masses; and the secondary influence of density and Poisson's ratio is considered at the same time, so that the damage degree quantification is more accurate.

Description

Technical Field

[0001] This invention relates to the field of rock mass engineering technology, and in particular to a method for calculating the deformation modulus of in-situ rock mass. Background Technology

[0002] The deformation capacity, or modulus, of a rock mass is characterized by the ratio of the stress applied to the rock mass to the resulting deformation. These indicators include elastic modulus, tangential modulus, and deformation modulus. Since rock masses in engineering practice typically do not exhibit perfectly elastic characteristics, deformation modulus is the most widely used indicator among various rock mass moduli. How to quickly and accurately determine the deformation modulus of a rock mass is an important topic in rock mechanics and rock engineering.

[0003] Currently, methods for determining the deformation modulus of in-situ rock mass mainly fall into two categories: The first category is the in-situ testing method, such as directly conducting loading tests in the field through bearing plate tests and borehole modulus tests. Although this method is intuitive and considered the most reliable approach, it generally suffers from inherent drawbacks such as high testing costs, long cycles, complex operations, and high requirements for site conditions, making it difficult to apply on a large scale in engineering practice, especially in small and medium-sized projects or the early stages of exploration. The second category is estimation methods based on empirical relationships. These methods rely on the statistical relationship between established rock mass quality evaluation systems and deformation modulus. In engineering practice, rock mass quality is usually first classified using a comprehensive evaluation system of multiple indicators, such as the Geomechanical Classification Index (GSI), Rock Mass Quality Rating (RMR), Q system, and Basic Quality (BQ). In addition, the in-situ elastic P-wave velocity of rock mass obtained through geological borehole tests has become an important field-measured indicator for characterizing rock mass quality due to its significant advantages such as speed, economy, and objective data. Furthermore, the elastic P-wave velocity of rock mass is the only field-measured parameter for calculating the BQ index. After obtaining the rock mass quality indicators, an empirical formula between them and the deformation modulus is established through data regression analysis, thereby achieving indirect estimation of the deformation modulus.

[0004] However, existing empirical estimation methods have significant limitations and shortcomings. First, most of these empirical relationships are established through statistical fitting based on limited datasets from specific engineering sites, and their formulas and fitting coefficients are strongly dependent on local data characteristics. When these empirical relationships are extended to other projects with different geological conditions, rock types, or engineering scales, their applicability often suffers due to differences in geological background, resulting in significant biases in the estimation results and a lack of universality and generality. Second, existing methods largely rely on multi-index comprehensive scoring systems, the evaluation process of which inevitably carries a certain degree of subjectivity, and they fail to systematically elucidate the intrinsic mechanical relationship between rock mass quality indicators and deformation modulus from a theoretical perspective.

[0005] Therefore, traditional methods for calculating the deformation modulus of in-situ rock masses rely mainly on statistical empirical formulas for specific sites. Their theoretical foundation is weak and they do not systematically consider core mechanical mechanisms such as the relationship between rock mass damage and dynamic and static parameters. This results in poor applicability, insufficient universality, and the estimation results being greatly affected by subjective experience. Summary of the Invention

[0006] Based on this, in order to solve the above-mentioned technical problems, a method for calculating the deformation modulus of in-situ rock mass is provided, which can be adaptively adjusted according to rock mass indicators to improve applicability and the calculation accuracy of the deformation modulus of in-situ rock mass.

[0007] A method for calculating the deformation modulus of in-situ rock mass, the method comprising:

[0008] The density, Poisson's ratio, and P-wave velocity of intact rock blocks in the in-situ site are obtained, and the P-wave velocity of jointed rock masses is also obtained; each interval number is set, wherein the density of the jointed rock mass is represented by the interval number of the density of the intact rock block, and the Poisson's ratio of the jointed rock mass is represented by the interval number of the Poisson's ratio of the intact rock block;

[0009] Based on a dataset containing rock names, elastic longitudinal wave velocities, and deformation moduli, and combining the relationship between dynamic elastic modulus and density, Poisson's ratio, and longitudinal wave velocity in dynamic elasticity theory, the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus is obtained through interval number arithmetic rules.

[0010] The relationship between the longitudinal wave velocity and dynamic elastic modulus, density, and Poisson's ratio of the intact rock block and the jointed rock mass is calculated. Based on the dynamic / static modulus ratio between the intact rock block and the jointed rock mass, the normalized damage degree of the in-situ rock mass is calculated using the binary function operation rule.

[0011] The P-wave modulus of the intact rock block is calculated, and the P-wave modulus is corrected using the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, as well as the normalized damage degree, to obtain the deformation modulus of the in-situ rock mass.

[0012] In one embodiment, the density, Poisson's ratio, and P-wave velocity of intact rock blocks in the in-situ site are obtained, and the P-wave velocity of jointed rock masses is obtained, including:

[0013] The density and Poisson's ratio of a complete rock block can be obtained through laboratory density testing, uniaxial compression testing, or from a pre-set table of rock density and Poisson's ratio empirical values ​​based on the rock name.

[0014] The longitudinal wave velocity of the intact rock block is obtained through laboratory or field measurements.

[0015] The longitudinal wave velocity of the jointed rock mass is obtained by on-site geological drilling or exposure of the rock mass.

[0016] In one embodiment, based on a dataset containing rock name, elastic P-wave velocity, and deformation modulus, and combining the relationship between dynamic elastic modulus and density, Poisson's ratio, and P-wave velocity in dynamic elasticity theory, the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus is obtained through interval number arithmetic rules, including:

[0017] Based on a dataset containing rock names, elastic longitudinal wave velocities, and deformation moduli, and combined with a processing method that treats the density and Poisson's ratio of jointed rock masses as intervals based on intact rock block parameters, a connection is established between the dynamic elastic modulus and deformation modulus of the rock mass, and the dynamic / static modulus ratio of the rock mass is obtained.

[0018] By using interval number arithmetic rules to eliminate the influence of density and Poisson's ratio, the relationship between the dynamic / static modulus ratio and the deformation modulus of the in-situ rock mass is obtained.

[0019] In one embodiment, the relationship between the longitudinal wave velocity and the dynamic elastic modulus, density, and Poisson's ratio of the intact rock mass is calculated, and the relationship between the longitudinal wave velocity and the dynamic elastic modulus, density, and Poisson's ratio of the jointed rock mass includes:

[0020] Determine the dynamic elastic modulus of the intact rock block, and calculate the relationship between the longitudinal wave velocity and the dynamic elastic modulus, density, and Poisson's ratio of the intact rock block;

[0021] The dynamic elastic modulus of the jointed rock mass is determined, and the relationship between the longitudinal wave velocity, dynamic elastic modulus, density, and Poisson's ratio of the jointed rock mass is calculated.

[0022] In one embodiment, based on the dynamic / static modulus ratio between the intact rock block and the jointed rock mass, the normalized damage degree of the in-situ rock mass is calculated using a binary function algorithm, including:

[0023] Under the premise that the ratio of the dynamic elastic modulus to the static elastic modulus is equal between the intact rock block and the jointed rock mass, the auxiliary variables of the intact rock block are calculated.

[0024] Obtain auxiliary variables determined based on the differences in density and Poisson's ratio between the intact rock block and the jointed rock mass, and take the midpoint of the interval;

[0025] By using the binary function operation rules, the normalized damage degree of the in-situ rock mass is calculated based on the auxiliary variable and the interval midpoint.

[0026] In one embodiment, the P-wave modulus of the intact rock block is calculated, and the P-wave modulus is corrected using the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, and the normalized damage degree, to obtain the deformation modulus of the in-situ rock mass, including:

[0027] Calculate the P-wave modulus of the intact rock block, and obtain a formula for calculating the in-situ rock mass deformation modulus based on the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, and the normalized damage degree.

[0028] By iterating or substituting into the calculation formula, the theoretical angle of the P-wave modulus is corrected, and the deformation modulus of the in-situ rock mass is obtained.

[0029] In one embodiment, the method further includes:

[0030] Obtain the measured values ​​of rock mass deformation modulus from in-situ tests.

[0031] The measured values ​​are compared with the calculated deformation modulus of the in-situ rock mass to complete the accuracy verification.

[0032] The aforementioned method for calculating the deformation modulus of in-situ rock masses, based on an existing dataset consisting of rock name, elastic P-wave velocity, and deformation modulus, uses interval number arithmetic to derive an exponential function relationship between the dynamic / static modulus ratio and the deformation modulus of the rock mass. It then calculates the normalized damage degree of the in-situ rock mass using a binary function arithmetic based on the relative differences in density and Poisson's ratio between intact rock blocks and jointed rock masses. Finally, it corrects the P-wave modulus of the intact rock block using the dynamic / static modulus ratio and damage degree, thus obtaining the in-situ rock mass deformation modulus. Based on theoretical derivation rather than a specific engineering dataset, this method is applicable to different types of rock masses. Furthermore, by simultaneously considering the secondary effects of density and Poisson's ratio, the quantification of damage degree is more accurate, the calculation error is lower, and the practicality and accuracy of in-situ rock mass deformation modulus calculations are improved. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating a method for calculating the deformation modulus of in-situ rock mass in one embodiment;

[0034] Figure 2 This is a flowchart illustrating the method for calculating the deformation modulus of in-situ rock mass in another embodiment. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] In one embodiment, such as Figure 1 As shown, a method for calculating the deformation modulus of in-situ rock mass is provided, including the following steps:

[0037] Step 102: Obtain the density, Poisson's ratio, and P-wave velocity of intact rock blocks in the in-situ site, and obtain the P-wave velocity of jointed rock masses; set the interval numbers, the density of jointed rock masses is represented by the interval number of the density of intact rock blocks, and the Poisson's ratio of jointed rock masses is represented by the interval number of the Poisson's ratio of intact rock blocks.

[0038] Before calculating the deformation modulus of in-situ rock mass, it is necessary to first determine the basic parameters, mainly the density, Poisson's ratio and P-wave velocity of intact rock blocks at the in-situ site, as well as the P-wave velocity of jointed rock masses.

[0039] In one embodiment, the method for calculating the deformation modulus of an in-situ rock mass may further include a process for determining basic parameters. The specific process includes: obtaining the density and Poisson's ratio of a complete rock block through laboratory density testing, uniaxial compression testing, or by obtaining the density and Poisson's ratio of the complete rock block from a preset table of rock density and Poisson's ratio empirical values ​​based on the rock name; obtaining the longitudinal wave velocity of the complete rock block through laboratory or field testing; and obtaining the longitudinal wave velocity of the jointed rock mass through field geological drilling or exposed rock mass testing.

[0040] Specifically, the density ρ and Poisson's ratio μ of a intact rock block can be obtained using laboratory measurements or empirical values ​​determined based on the rock name; the elastic longitudinal wave velocity V of the intact rock block... pr Elastic longitudinal wave velocity V of jointed rock mass pm The measured values ​​should be used. Among the empirical values ​​determined based on rock name, the statistical results for some rocks are shown in the table below:

[0041]

[0042] In this embodiment, the method also includes setting the number of each interval. The process, We can approximate these values ​​as 5%, 10%, 5%, and 20%–100%, respectively. The value is determined based on the rock mass quality characteristics, i.e., its quality. For good rock mass quality, d is taken as 20%–50%, and for poor rock mass quality… Take 50% to 100%.

[0043] Step 104: Based on a dataset containing rock name, elastic longitudinal wave velocity, and deformation modulus, and combining the relationship between dynamic elastic modulus and density, Poisson's ratio, and longitudinal wave velocity in dynamic elasticity theory, the relationship between dynamic / static modulus ratio and rock mass deformation modulus is obtained through interval number arithmetic rules.

[0044] Based on the existing dataset consisting of rock name, elastic P-wave velocity, and deformation modulus, the density and Poisson's ratio of the rock mass are expressed as interval numbers corresponding to the complete rock block. According to the theoretical formula of dynamic elastic modulus with density, Poisson's ratio, and P-wave velocity in dynamic elasticity theory, and with the introduction of the dimensionless coefficient of dynamic / static modulus ratio, the interval number operation rule is used to eliminate the influence of density, Poisson's ratio, and P-wave velocity in the theoretical formula. Based on this, the relationship between the dynamic / static modulus ratio and the deformation modulus of the in-situ rock mass is obtained.

[0045] Specifically, in one embodiment, the method for calculating the deformation modulus of in-situ rock mass may further include deriving the relationship between the dynamic / static modulus ratio and the deformation modulus of the rock mass. The specific process includes: based on a dataset containing rock name, elastic longitudinal wave velocity, and deformation modulus, and combined with a processing method that treats the density and Poisson's ratio of jointed rock mass as interval numbers based on the parameters of intact rock blocks, establishing a connection between the dynamic elastic modulus and deformation modulus of the rock mass to obtain the dynamic / static modulus ratio of the rock mass; and using interval number arithmetic rules to eliminate the influence of density and Poisson's ratio to obtain the relationship between the dynamic / static modulus ratio and the deformation modulus of the in-situ rock mass.

[0046] According to the basic theory of dynamic elasticity, the relationship between the dynamic elastic modulus of rock mass and its density, Poisson's ratio, and longitudinal wave velocity can be expressed as:

[0047] (1)

[0048] in, and These are the density, Poisson's ratio, and longitudinal wave propagation velocity of the in-situ rock mass, respectively. This is the dynamic elastic modulus of the rock mass. It's important to note that if... The unit is g. If the unit is km / s, then the value in GPa can be obtained. Predicted value.

[0049] Since P-wave velocity is a dynamic parameter, the modulus directly calculated from elastic P-wave velocity is also a dynamic parameter, while the deformation modulus used in engineering practice is a static parameter. Therefore, to avoid potential errors caused by the conversion between dynamic and static parameters of the rock mass, it is logical to establish a direct relationship between the dynamic elastic modulus and the deformation modulus of the rock mass. The formula is as follows:

[0050] (2)

[0051] in, is the dynamic / static modulus ratio of the rock mass, and is a dimensionless constant; It is the deformation modulus of the rock mass, and the unit is GPa.

[0052] Substituting equation (1) into equation (2) and performing appropriate transformations, we obtain:

[0053] (3)

[0054] To obtain the dynamic / static modulus ratio of the in-situ rock mass, it is necessary to use interval arithmetic rules to simplify the terms on the right side of equation (3) that contain density and Poisson's ratio. This part can be denoted as As shown in the following formula:

[0055] (4)

[0056] For intact rock blocks and jointed rock masses, their densities and Poisson's ratios have a numerical relationship, namely:

[0057] (5)

[0058] Density of jointed rock mass Compared to Poisson The above characteristics are largely consistent with the concept and basic properties of interval numbers, therefore, and The density of the intact rock block can be used separately. Compared to Poisson The interval numbers are represented as follows:

[0059] (6)

[0060] in, and These are the density and Poisson's ratio of the intact rock block, respectively. All are real numbers, depending on the difference between the density and Poisson's ratio of intact rock blocks and jointed rock masses, and satisfying the following conditions: .

[0061] Substituting equation (6) into equation (5), we get:

[0062] (7)

[0063] Since there is a numerical relationship between the density and Poisson's ratio between intact rock blocks and jointed rock masses, according to existing research, in equation (7) We can approximate these values ​​as 5%, 10%, 5%, and 20%–100%, respectively. Using a dataset from existing literature consisting of rock name, elastic longitudinal wave velocity, and deformation modulus, we can eliminate the three basic and known physical quantities of rock mass density, Poisson's ratio, and elastic longitudinal wave velocity in equation (3). Based on this, we can obtain the relationship between the dynamic / static modulus ratio of the rock mass and the deformation modulus of the rock mass, as shown in the following equation:

[0064] (8)

[0065] Step 106: Calculate the relationship between the longitudinal wave velocity and dynamic elastic modulus, density and Poisson's ratio of the intact rock block, and the relationship between the longitudinal wave velocity and dynamic elastic modulus, density and Poisson's ratio of the jointed rock mass. Based on the dynamic / static modulus ratio between the intact rock block and the jointed rock mass, calculate the normalized damage degree of the in-situ rock mass using the binary function operation rule.

[0066] Based on the relative difference in density and Poisson's ratio between two media, intact rock blocks and jointed rock masses, and according to the basic properties of bivariate functions, a calculation formula for characterizing the degree of in-situ rock mass damage is obtained by considering the attenuation of elastic longitudinal wave velocity of jointed rock masses relative to intact rock blocks, as well as the influence of density and Poisson's ratio between the two.

[0067] In one embodiment, the method for calculating the deformation modulus of an in-situ rock mass may further include the process of calculating the relationship between longitudinal wave velocity and dynamic elastic modulus. The specific process includes: determining the dynamic elastic modulus of a complete rock mass and calculating the relationship between the longitudinal wave velocity of the complete rock mass and its dynamic elastic modulus, density, and Poisson's ratio; determining the dynamic elastic modulus of a jointed rock mass and calculating the relationship between the longitudinal wave velocity of the jointed rock mass and its dynamic elastic modulus, density, and Poisson's ratio.

[0068] Specifically, by appropriately transforming equation (1), the relationship between the longitudinal wave velocity of the jointed rock mass and its dynamic elastic modulus, density, and Poisson's ratio can be expressed as:

[0069] (9)

[0070] Similarly, the relationship between the longitudinal wave velocity of a complete rock block and its dynamic elastic modulus, density, and Poisson's ratio can be expressed as:

[0071] (10)

[0072] In one embodiment, a method for calculating the deformation modulus of in-situ rock mass may further include a process for calculating the normalized damage degree. The specific process includes: calculating an auxiliary variable for the intact rock mass, provided that the ratio of the dynamic elastic modulus to the static elastic modulus is equal between the intact rock mass and the jointed rock mass; obtaining the auxiliary variable determined based on the differences in density and Poisson's ratio between the intact rock mass and the jointed rock mass and taking the midpoint of the interval; and calculating the normalized damage degree of the in-situ rock mass based on the auxiliary variable and the midpoint of the interval using a binary function operation rule.

[0073] The ratio of the dynamic elastic modulus to the static elastic modulus is equal between intact rock blocks and jointed rock masses, that is:

[0074] (11)

[0075] Since the development of defects (i.e., damage) leads to a decrease in material stiffness, the degree of damage can also be characterized by the change in the elastic modulus of the material before and after damage occurs, i.e.:

[0076] (12)

[0077] Combining equations (9), (10), and (12), the normalized damage degree of the in-situ rock mass can be further expressed as:

[0078] (13)

[0079] In the formula, D is the normalized damage degree of the in-situ rock mass, and D=0 and D=1 represent the initial undamaged state and the final fully damaged state, respectively. and These represent the density, Poisson's ratio, and P-wave velocity of a complete rock mass. The density and uniaxial compression tests in the laboratory can be obtained respectively. In the preliminary estimation stage, the results can be obtained directly from the table based on the rock name. This is an auxiliary variable concerning intact rock, which can be calculated using the following equation:

[0080] (14)

[0081] To simplify equation (13), an auxiliary variable λ can be introduced, and equation (13) can be further rewritten as follows:

[0082] (15)

[0083] in,

[0084] (16)

[0085] In the formula, .

[0086] For density is Compared with Poisson, For a specific rock mass, in formula (15) The range of values ​​for can be calculated through the following derivation process. For this purpose, intermediate variables A and B are introduced here, resulting in:

[0087] (17)

[0088] In the formula, , .

[0089] For equation (17) and Taking the partial derivatives of each, we get:

[0090] (18)

[0091] For both intact rock blocks and jointed rock masses, because ,but , .

[0092] In conclusion:

[0093] (19)

[0094] From the properties of bivariate functions, we can obtain:

[0095] (20)

[0096] Therefore, The midpoint of the interval can be calculated as follows:

[0097] (twenty one)

[0098] Through the above derivation, a simplified method for characterizing the degree of damage to in-situ rock mass can be obtained. It is mainly based on the key factor of longitudinal wave velocity of rock mass, and also considers the two secondary factors of density and Poisson's ratio. Compared with the existing traditional method that directly ignores the two factors of density and Poisson's ratio, the calculation method of Equation (21) is more reasonable and can more accurately evaluate the degree of damage to in-situ rock mass.

[0099] Step 108: Calculate the P-wave modulus of the intact rock block, and correct the P-wave modulus using the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, and the normalized damage degree, to obtain the deformation modulus of the in-situ rock mass.

[0100] In one embodiment, the method for calculating the deformation modulus of in-situ rock mass may further include the process of calculating the deformation modulus of in-situ rock mass. The specific process includes: calculating the P-wave modulus of the intact rock block, and obtaining a formula for calculating the deformation modulus of in-situ rock mass based on the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus and the normalized damage degree; iterating or substituting into the calculation formula to achieve theoretical angle correction of the P-wave modulus, and obtaining the deformation modulus of the in-situ rock mass.

[0101] Specifically, combining equations (15) and (16), equation (3) can be rewritten in the following form:

[0102] (twenty two)

[0103] Note that λ in equation (22) can be expressed in another form to represent the degree of damage. Replace, at the same time Need to use Alternatively, this expression can be rewritten in another form, as shown below:

[0104] (twenty three)

[0105] The combined parameters on the right side of the formula It has a specific physical meaning and is called the P-wave modulus of the intact rock mass. Furthermore, substituting equation (8) into equation (22), we obtain the following theoretical equation for calculating the deformation modulus of in-situ rock masses:

[0106] (twenty four)

[0107] Similarly, the above formula can also be rewritten in another form, as shown below:

[0108] (25)

[0109] It is worth noting that the density in equations (24) and (25) The unit is still And elastic longitudinal wave velocity and The unit is Therefore, the combined terms in equations (24) and (25), namely and It has the same dimensions as the modulus of the material, that is... The dimensions of the remaining terms are all 1.

[0110] For practical engineering applications, using equation (24) or equation (25) requires determining the density ρ and Poisson's ratio of the intact rock block. and elastic longitudinal wave velocity Elastic longitudinal wave velocity of jointed rock mass and the aforementioned coefficients .

[0111] In one embodiment, the method for calculating the deformation modulus of in-situ rock mass may further include a process for verifying the accuracy of the calculation results. The specific process includes: obtaining the measured value of the deformation modulus of in-situ rock mass from on-site in-situ testing; comparing the measured value with the calculated deformation modulus of the in-situ rock mass to complete the accuracy verification.

[0112] In one embodiment, the specific flow of a method for calculating the deformation modulus of in-situ rock mass is as follows: Figure 2 As shown, firstly, it is necessary to clarify the rock properties and determine the rock name for on-site dynamic parameter testing. This is the basis for subsequent parameter selection and method applicability judgment. Simultaneously, in-situ rock mass P-wave velocity testing is carried out, mainly by using geological boreholes or exposed rock masses to quickly obtain the elastic P-wave velocity of the in-situ rock mass. This parameter is a key indicator for characterizing the in-situ dynamic characteristics of the rock mass.

[0113] Next, the transition from the field to the laboratory involves core drilling or obtaining large-sized rock blocks, primarily to obtain representative rock samples from the engineering site to ensure that the samples are consistent with the geological properties of the in-situ rock mass; these samples are then processed into standard cylindrical specimens, that is, the rock blocks are processed into cylindrical specimens that meet the testing requirements according to rock mechanics testing specifications.

[0114] Next, it is necessary to look up the table or test the density and Poisson's ratio of the rock block. The density can be obtained through laboratory density testing, and the Poisson's ratio can be obtained through mechanical tests such as uniaxial compression tests. Then, the longitudinal wave velocity of the rock block is tested, that is, the longitudinal wave velocity of the cylindrical standard specimen is tested in the laboratory to obtain the longitudinal wave velocity of the complete rock block, which is used for subsequent comparative analysis with the longitudinal wave velocity of the in-situ rock mass.

[0115] Quantitative rock mass damage and parameter range difference determination coefficients, which are used to describe the range differences in density and Poisson's ratio between jointed rock masses and intact rock blocks;

[0116] Finally, by substituting the previously obtained longitudinal wave velocity of the in-situ rock mass, the density of the intact rock block, Poisson's ratio and longitudinal wave velocity, as well as the determined coefficients, into the theoretical equation for calculating the deformation modulus of the in-situ rock mass, the theoretical calculated value of the deformation modulus of the in-situ rock mass can be obtained, thus realizing a quantitative assessment of the deformation capacity of the rock mass.

[0117] In one embodiment, the in-situ deformation modulus test data of a dam foundation rock mass is used as an example for detailed explanation. The specific implementation steps are as follows:

[0118] Rock name: Sandstone;

[0119] Rock density Compared to Poisson : 0.23;

[0120] Rock wave velocity 5.050 km / s;

[0121] Rock mass wave velocity 3.730 km / s;

[0122] coefficient 5%, 10%, 5%, and 45%;

[0123] Deformation modulus Measured value: 6.85 GPa.

[0124] Deformation modulus Calculated value:

[0125]

[0126]

[0127] Deformation modulus Error of calculated value relative to measured value for:

[0128]

[0129] As can be seen from the above calculations, the deformation modulus The calculated value is 6.23 GPa, while the measured value is 6.85 GPa. The error between the calculated value and the measured value is 9.07%. Therefore, for the calculation results of this embodiment, the in-situ rock mass deformation modulus calculation formula proposed in this application has high accuracy.

[0130] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0131] The embodiments described above merely illustrate the implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for calculating the deformation modulus of in-situ rock mass, characterized in that, The method includes: The density, Poisson's ratio, and P-wave velocity of intact rock blocks in the in-situ site are obtained, and the P-wave velocity of jointed rock masses is also obtained; each interval number is set, wherein the density of the jointed rock mass is represented by the interval number of the density of the intact rock block, and the Poisson's ratio of the jointed rock mass is represented by the interval number of the Poisson's ratio of the intact rock block; Based on a dataset containing rock names, elastic longitudinal wave velocities, and deformation moduli, and combining the relationship between dynamic elastic modulus and density, Poisson's ratio, and longitudinal wave velocity in dynamic elasticity theory, the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus is obtained through interval number arithmetic rules. The relationship between the longitudinal wave velocity and dynamic elastic modulus, density, and Poisson's ratio of the intact rock block and the jointed rock mass is calculated. Based on the dynamic / static modulus ratio between the intact rock block and the jointed rock mass, the normalized damage degree of the in-situ rock mass is calculated using the binary function operation rule. The P-wave modulus of the intact rock block is calculated, and the P-wave modulus is corrected using the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, as well as the normalized damage degree, to obtain the deformation modulus of the in-situ rock mass.

2. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, Obtain the density, Poisson's ratio, and P-wave velocity of intact rock blocks in the in-situ site, and obtain the P-wave velocity of jointed rock masses, including: The density and Poisson's ratio of a complete rock block can be obtained through laboratory density testing, uniaxial compression testing, or from a pre-set table of rock density and Poisson's ratio empirical values ​​based on the rock name. The longitudinal wave velocity of the intact rock block is obtained through laboratory or field measurements. The longitudinal wave velocity of the jointed rock mass is obtained by on-site geological drilling or exposure of the rock mass.

3. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, Based on a dataset containing rock names, elastic P-wave velocities, and deformation moduli, and combining the relationship between dynamic elastic modulus and density, Poisson's ratio, and P-wave velocity in dynamic elasticity theory, the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus is obtained through interval number arithmetic rules, including: Based on a dataset containing rock names, elastic longitudinal wave velocities, and deformation moduli, and combined with a processing method that treats the density and Poisson's ratio of jointed rock masses as intervals based on intact rock block parameters, a connection is established between the dynamic elastic modulus and deformation modulus of the rock mass, and the dynamic / static modulus ratio of the rock mass is obtained. By using interval number arithmetic rules to eliminate the influence of density and Poisson's ratio, the relationship between the dynamic / static modulus ratio and the deformation modulus of the in-situ rock mass is obtained.

4. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, The relationships between the longitudinal wave velocity and dynamic elastic modulus, density, and Poisson's ratio of the intact rock mass, and the relationships between the longitudinal wave velocity and dynamic elastic modulus, density, and Poisson's ratio of the jointed rock mass, are calculated, including: Determine the dynamic elastic modulus of the intact rock block, and calculate the relationship between the longitudinal wave velocity and the dynamic elastic modulus, density, and Poisson's ratio of the intact rock block; The dynamic elastic modulus of the jointed rock mass is determined, and the relationship between the longitudinal wave velocity, dynamic elastic modulus, density, and Poisson's ratio of the jointed rock mass is calculated.

5. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, Based on the dynamic / static modulus ratio between the intact rock block and the jointed rock mass, the normalized damage degree of the in-situ rock mass is calculated using a binary function algorithm, including: Under the premise that the ratio of the dynamic elastic modulus to the static elastic modulus is equal between the intact rock block and the jointed rock mass, the auxiliary variables of the intact rock block are calculated. Obtain auxiliary variables determined based on the differences in density and Poisson's ratio between the intact rock block and the jointed rock mass, and take the midpoint of the interval; By using the binary function operation rules, the normalized damage degree of the in-situ rock mass is calculated based on the auxiliary variable and the interval midpoint.

6. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, The P-wave modulus of the intact rock block is calculated, and the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, along with the normalized damage degree, is used to correct the P-wave modulus to obtain the in-situ rock mass deformation modulus, including: Calculate the P-wave modulus of the intact rock block, and obtain a formula for calculating the in-situ rock mass deformation modulus based on the relationship between the dynamic / static modulus ratio and the rock mass deformation modulus, and the normalized damage degree. By iterating or substituting into the calculation formula, the theoretical angle of the P-wave modulus is corrected, and the deformation modulus of the in-situ rock mass is obtained.

7. The method for calculating the deformation modulus of in-situ rock mass according to claim 1, characterized in that, The method further includes: Obtain the measured values ​​of the in-situ rock mass deformation modulus from the on-site in-situ test. The measured values ​​are compared with the calculated deformation modulus of the in-situ rock mass to complete the accuracy verification.

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