Method for calculating shear strength of weak structural plane based on Barton formula

Abstract

The invention discloses a method for calculating the shear strength of a weak structural plane based on a Barton formula, and relates to the field of shear strength calculation, and the method comprises the following steps: introducing a reduction coefficient into a traditional Barton formula, and constructing an improved Barton formula; the shear strength of the weak structural plane is calculated through an improved Barton formula; the improved calculation model is regressed into an original Barton formula when no filler exists, theoretical continuity is guaranteed, compatibility with a traditional model is achieved, meanwhile, the defects of the traditional model are well overcome, and an important theoretical basis is provided for prediction of the shear strength of the weak structural plane. An improved Barton formula is utilized, the weakening effect of the soft filler on the rock mass structural surface can be reflected, the relation between the thickness of the soft filler and rock wall roughness attenuation can be accurately quantified, and compatibility with a traditional model is achieved; and the applicability, reliability and precision of prediction of the shear strength of the weak structural plane are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of shear strength calculation, and more particularly to a method for calculating the shear strength of a weak structural surface based on the Barton formula. Background Art

[0002] The traditional Barton formula is the core empirical model for evaluating the shear strength of rock mass structural surfaces. It is applicable to structural surfaces such as unfilled or lightly filled rough joints and cracks. Its core is to modify the basic internal friction angle of rock by using the joint roughness and compressive strength. Its expression is: Among them, τ is the shear strength of the rock mass structural surface, σ n is the normal stress acting on the structural surface, φ b is the basic internal friction angle of rock, obtained through direct shear tests on rock specimens; JRC is the joint roughness coefficient, used to describe the roughness of the structural surface, ranging from 0 to 20, determined by comparing with standard roughness profiles (10 typical curves proposed by Barton); JCS is the joint wall compressive strength, that is, the compressive strength of the structural surface (MPa), which is the uniaxial compressive strength of rock when unweathered. When weathered, it can be tested and converted on-site using a rebound hammer.

[0003] This method works well in intact rock masses and hard structural surfaces, but has certain drawbacks in structural surfaces containing soft fillings of a certain thickness:

[0004] ① The isolation effect of weak filling materials (such as clay and fault gouge) was not considered, and the contribution of roughness was overestimated, resulting in an overestimation of the predicted shear strength.

[0005] ② The weak filler's own strength is missing. The formula does not consider the contribution of the weak filler's cohesion c to the shear strength of the structural surface, ignores its shear properties as an independent medium, and cannot fully characterize the filler's shear failure mode.

[0006] ③ The influence of fillers is judged only by experience, and there is a lack of quantitative relationship between the thickness of weak fillers and roughness attenuation, which leads to the deviation of the strength calculation of structural surfaces with thin and thick fillings from reality. Summary of the Invention

[0007] The purpose of the present invention is to provide a method for calculating the shear strength of weak structural surfaces based on the Barton formula, and to improve the traditional Barton formula based on the contact mechanics theory and the law of conservation of energy to enhance the universality and reliability of the formula.

[0008] The above technical objectives of the present invention are achieved through the following technical solutions:

[0009] In a first aspect, the present application provides a method for calculating the shear strength of a weak structural plane based on the Barton formula, including the following specific steps:

[0010] Introduce a reduction coefficient into the traditional Barton formula and construct an improved Barton formula;

[0011] Calculate the shear strength of the weak structural plane through the improved Barton formula.

[0012] Based on the above technical solution, the present invention can also be improved as follows.

[0013] Further, the above-mentioned improved Barton formula is specifically:

[0014]

[0015] In the formula, τ represents the shear strength of the weak structural plane, σ n is the normal stress acting on the weak structural plane, φ fill represents the internal friction angle of the weak filling material; JRC is the joint roughness coefficient; JCS is the joint wall compressive strength, k represents the reduction coefficient, and c represents the cohesion of the weak filling material.

[0016] Further, the above-mentioned reduction coefficient is obtained through the following method:

[0017]

[0018] In the formula, k represents the reduction coefficient, s represents the thickness of the filling material of the weak structural plane, s o represents the characteristic dissipation thickness.

[0019] Further, the above-mentioned characteristic dissipation thickness is determined through the following method:

[0020] Fabricate structural test specimens with different thicknesses of weak filling materials, and ensure that the filling materials are evenly distributed and in good contact with the rock wall;

[0021] Use direct shear tests to obtain the shear strength parameters of the weak filling materials. The shear strength parameters include cohesion and internal friction angle. Obtain the joint roughness coefficient by comparing with the standard roughness profile diagram, and obtain the joint wall compressive strength through rock uniaxial compressive strength tests;

[0022] Conduct direct shear tests on the structural test specimens with different thicknesses of weak filling materials and record the peak shear strength;

[0023] Calculate the reduction coefficient based on the data of each structural test specimen obtained from the tests;

[0024] Perform linear regression fitting on each group of reduction coefficients and each group of weak filling material thicknesses, and obtain the characteristic dissipation thickness according to the fitting slope.

[0025] Furthermore, the reduction coefficient is calculated based on the data of each structural surface specimen obtained from the test, specifically as follows:

[0026]

[0027] In the formula, σ n is the normal stress acting on the weak structural surface, and φ fill represents the internal friction angle of the weak filling material; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, c represents the cohesion of the weak filling material, and τ represents the peak shear strength.

[0028] In a second aspect, the present application provides a system for calculating the shear strength of a weak structural surface based on the Barton formula, including:

[0029] A first module for introducing a reduction coefficient into the traditional Barton formula and constructing an improved Barton formula;

[0030] A second module for calculating the shear strength of the weak structural surface through the improved Barton formula.

[0031] Furthermore, the specific form of the above-mentioned improved Barton formula is:

[0032]

[0033] In the formula, τ represents the shear strength of the weak structural surface, and σ n is the normal stress acting on the weak structural surface, and φ fill represents the internal friction angle of the weak filling material; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, and c represents the cohesion of the weak filling material;

[0034] Furthermore, the reduction coefficient in the system is obtained through the following method:

[0035]

[0036] In the formula, k represents the reduction coefficient, s represents the thickness of the filling material on the weak structural surface, and s o represents the characteristic dissipation thickness.

[0037] Furthermore, the characteristic dissipation thickness in the above-mentioned system is determined through the following method:

[0038] Fabricate structural surface specimens with different thicknesses of weak filling materials, and ensure that the filling materials are evenly distributed and in good contact with the rock wall;

[0039] The shear strength parameters of the soft filler are obtained by direct shear tests. The shear strength parameters include cohesion and internal friction angle. The joint roughness coefficient is obtained by comparing with the standard roughness profile, and the joint wall compressive strength is obtained by uniaxial compressive strength tests of rocks.

[0040] The direct shear tests on the structural plane specimens with different soft filler thicknesses are carried out, and the peak shear strength is recorded.

[0041] The reduction coefficient is calculated according to the data of each structural plane specimen obtained from the tests.

[0042] The linear regression fitting is performed on each group of reduction coefficients and each group of soft filler thicknesses, and the characteristic dissipation thickness is obtained according to the fitting slope.

[0043] Furthermore, in the above system, the reduction coefficient is calculated according to the data of each structural plane specimen obtained from the tests. Specifically:

[0044]

[0045] In the formula, σ n is the normal stress acting on the soft structural plane, φ fill represents the internal friction angle of the soft filler; JRC is the joint roughness coefficient; JCS is the joint wall compressive strength, k represents the reduction coefficient, c represents the cohesion of the soft filler, and τ represents the peak shear strength.

[0046] In a third aspect, the present application provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the method according to any one of the first aspects is implemented.

[0047] In a fourth aspect, the present application provides a non-transitory computer-readable storage medium. The non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the method according to any one of the first aspects.

[0048] Compared with the prior art, the present invention has at least the following beneficial effects:

[0049] In this application, in order to improve the prediction accuracy of the shear strength of weak structural planes, a reduction coefficient is introduced to quantify the weakening effect of the thickness of weak fillers on the incremental friction angle of roughness. According to the law of conservation of energy during the shear process of the structural plane, a scale parameter, the characteristic dissipation thickness, which characterizes the energy dissipation efficiency of weak fillers, is introduced to construct a quadratic exponential decay calculation model for the reduction coefficient. Finally, the characteristic dissipation thickness is calibrated using experimental parameters to construct the final calculation model. The improved calculation model reverts to the original Barton formula when there is no filler, ensuring theoretical continuity and compatibility with traditional models. At the same time, it well solves the defects of traditional models, providing an important theoretical basis for the prediction of the shear strength of such weak structural planes.

[0050] In this application, the improved Barton formula can reflect the weakening effect of weak fillers on the rock mass structural plane, accurately quantify the relationship between the thickness of weak fillers and the attenuation of rock wall roughness, and achieve compatibility with traditional models. This method effectively improves the applicability, reliability, and accuracy of the prediction of the shear strength of weak structural planes, provides reliable input for slope stability calculation and support design, effectively reduces engineering design risks, and improves engineering safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of this application, and do not limit the embodiments of the present invention. In the drawings:

[0052] Figure 1 is a flowchart of the method in the embodiments of the present invention;

[0053] Figure 2 is a connection schematic diagram of the system in the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0055] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0056] It should be noted that: Similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0057] In the description of the embodiments of the present invention, "a plurality of" represents at least two.

[0058] Embodiment 1: Since the traditional Barton formula has good applicability in calculating the shear strength of rough joints, fissures and other structural planes with unfilled or slightly filled conditions, but there are certain deficiencies in the structural planes with soft fillers of a certain thickness. For example, the isolation effect of soft fillers is not considered, the contribution of roughness is overestimated, the contribution of the cohesion of the soft fillers themselves to the shear strength of the structural plane is not considered, and there is also a lack of a quantitative relationship between the thickness of the soft fillers and the attenuation of roughness. Therefore, the predicted shear strength of the structural plane often has a large deviation from the actual situation. Therefore, this embodiment provides a method for calculating the shear strength of soft structural planes based on the Barton formula, as Figure 1 shown, including the following specific steps:

[0059] S1, introduce a reduction coefficient into the traditional Barton formula and construct an improved Barton formula.

[0060] Among them, before improving the traditional Barton formula, it is necessary to conduct geological surveys and tests on the rock mass and structural planes in the study area; mainly including macroscopic geological character surveys, such as stratigraphic lithology, weathering degree, morphology and development distribution of structural planes, material composition and thickness of fillers, etc., analyze and describe the roughness of the studied structural planes, determine their joint roughness coefficients, conduct uniaxial compressive strength tests on unweathered rocks in the area, and determine the compressive strength of joint walls.

[0061] Furthermore, improve the traditional Barton formula based on the contact mechanics theory; in order to improve the traditional Barton formula to be applicable to structural planes with soft fillers, the following considerations can be made: ① The soft fillers are uniform and completely fill the structural plane; ② The contribution of the rock wall roughness to the strength decays with the increase in the thickness of the soft fillers.

[0062] The soft structural plane is composed of the contact surface between the soft filler and the rock wall, and its shear strength is composed of two parts: ① The shear strength of the soft filler itself; ② The additional shear strength generated by the increment of the friction angle caused by the rock wall roughness.

[0063] Among them, the shear strength of the soft filler itself is expressed according to the Mohr-Coulomb criterion, specifically as:

[0064] τ fill =c + σ n tanφ fill ; In the formula, τfill is the shear strength (MPa) of the soft filling; c is the cohesion (MPa) of the soft filling, and φ fill is the internal friction angle (°) of the soft filling.

[0065] Specifically, the increment of the friction angle caused by the rock wall roughness refers to the Barton formula. According to the Hertz contact theory, when two rough surfaces are in contact, the actual contact area is related to the normal load; when there is a filling, its thickness s will change the effective contact area, resulting in a weakening of the interlocking effect between the rough peaks, that is, the presence of the filling thickness s will partially or completely weaken the mechanical interlocking effect of the rock wall roughness; therefore, a reduction coefficient k related to the filling thickness s is introduced to describe the weakening effect of the presence of the filling on the increment of the friction angle of the roughness. Then the modified internal friction angle φ eff is:

[0066] Therefore, the total shear strength of the weak structural plane, that is, the improved Barton formula above is specifically:

[0067]

[0068] In the formula, τ represents the shear strength of the weak structural plane, and σ n is the normal stress acting on the weak structural plane, and φ fill represents the internal friction angle of the soft filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, and c represents the cohesion of the soft filling.

[0069] Furthermore, the reduction coefficient above can be calculated based on the principle of energy conservation; according to the law of energy conservation, during the shear process of the rock mass structure plane containing soft filling, the frictional energy generated by the interlocking action of the rough rock wall is equal to the energy dissipated by the plastic deformation or viscous flow of the soft filling. The dissipation power P of the frictional energy generated by the rough rock wall f is expressed as:

[0070]

[0071] Furthermore, under the condition of a rock wall with a certain roughness, the dissipation of roughness frictional energy plays a dominant role, and in order to focus on analyzing the variation law of the reduction coefficient k, the role of the filling friction angle φ fill in the energy dissipation is ignored, and under the condition of a small angle, tanθ≈θ (in radians). Therefore, the unit volume frictional energy E is:

[0072]

[0073] In the above formula, A is the contact area, v is the shear rate, and t is the shear time. The results show that the frictional energy per unit volume E of the structural plane during the shear process is related to the roughness (JRC), the normal stress (σ n ), and the reduction coefficient k, reflecting the superimposed effect of the contributions of the three to the frictional energy.

[0074] The soft filling dissipates energy through plastic deformation or viscous flow. The thickness of the filling is the geometric control variable of the energy transfer path. The greater the thickness, the longer the energy transfer path. Therefore, the energy dissipation efficiency of the filling is related to its thickness s and also depends on the material properties. Thus, the material constant characteristic dissipation thickness s0 is introduced, which is a characteristic parameter comprehensively reflecting the particle size, roughness, and stress state of the filling and is the characteristic scale characterizing the energy dissipation efficiency of the filling. Therefore, according to the energy conservation equation, the energy gradient of the frictional energy generated by the rough rock wall in the thickness space is equal to the energy gradient of the energy dissipation of the soft filling in the thickness space, and we can obtain:

[0075] Substituting the above formula for calculating the frictional energy per unit volume into this formula, we can get:

[0076] Simplifying this formula, we can get:

[0077] Separating variables and integrating this formula again, we can get:

[0078]

[0079] Combined with the initial condition that when s = 0, k = 1, we can solve for C = 0, and thus we can get:

[0080]

[0081] In the formula, k represents the reduction coefficient, s represents the thickness of the soft structural plane filling, and s o represents the characteristic dissipation thickness.

[0082] Furthermore, the calibration of the characteristic dissipation thickness s0. ① Prepare specimens, make structural plane specimens containing different soft filling thicknesses s (such as 1 mm, 2 mm, 4 mm, 6 mm), and ensure that the filling is evenly distributed and in good contact with the rock wall; ② Use the direct shear test to obtain the shear strength parameters c of the soft filling, and obtain the rock wall parameters JRC and JCS; ③ Conduct direct shear tests on the structural planes of different specimens and record the peak shear strength τ; ④ Calculate the k value according to the formula using the relevant data of each group of structural planes obtained from the tests; ⑤ Conduct linear regression fitting on the data of each group of k and s 2 and obtain s0 according to the fitting slope.

[0083] Among the above, the reduction coefficient is calculated according to the data of each structural surface specimen obtained from the test, specifically as follows:

[0084]

[0085] In the formula, σ n is the normal stress acting on the weak structural plane, φ fill represents the internal friction angle of the weak filling material; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, c represents the cohesion of the weak filling material, and τ represents the peak shear strength.

[0086] Specifically, construct the finally improved Barton formula: After determining the characteristic dissipation thickness s0, the formula: can be used to determine the calculation method of the reduction coefficient k, and substitute it into the formula: to obtain the improved Barton formula applicable to the weak structural plane.

[0087] S2. Calculate the shear strength of the weak structural plane through the improved Barton formula.

[0088] To better illustrate the implementation of the present invention, the following takes a weak structural plane of a hydropower station in the southwestern canyon area as an example for detailed description.

[0089] S11. Conduct geological surveys and tests on the rock mass and structural planes in the research area. Its lithology is medium-fine grained granodiorite. The research structural plane is not weathered, extends 20 - 30 m, has a weak interlayer, is mainly filled with mud, with a thickness of 3 - 5 mm, the filling is relatively uniform and almost completely fills the structural plane, the structural plane is moderately rough, and according to the JRC standard value table, its JRC value is 8. Unweathered rock is taken for uniaxial compressive strength test, and JCS is 65 MPa.

[0090] S12. Calibration of the characteristic dissipation thickness s0 of this type of weak structural plane. ① Prepare specimens, make structural plane specimens with weak filling material thicknesses of 1 mm, 2 mm, 3 mm, and 4 mm respectively, and ensure that the filling material is evenly distributed and in good contact with the rock wall; ② Use direct shear tests to obtain the shear strength parameters of the weak filling material c = 0.05 MPa, ③ Conduct direct shear tests on the structural planes of different specimens. All 4 groups of specimens are carried out under the condition that the normal stress σ n is 5 MPa, record the peak shear strength τ, which are 3.5 MPa, 3.2 MPa, 2.9 MPa, and 2.8 MPa respectively. The relevant data are shown in Table 1. ④ Use formula (3) to calculate the reduction coefficient k of the 4 groups of specimens under the corresponding conditions respectively, and the results are shown in Table 2. ⑤ Use formula (1), with x = lnk as the independent variable and y = s 2is the dependent variable, the slope m of the linear regression fitting line is -2s0, the fitted slope m is -6.2 mm, and the characteristic dissipation thickness s0 of this type of weak structural plane is obtained as 3.1 mm.

[0091] Table 1 Specimen Data Sheet

[0092]

[0093] Table 2 Data Sheet of Structural Plane Thickness s and Reduction Coefficient k

[0094]

[0095] S13. Construct the finally improved Barton formula for this type of weak structural plane; after determining the characteristic dissipation thickness s0, use formula (2) to determine the calculation method of the reduction coefficient k, and substitute it into the formula: The improved Barton formula applicable to this type of weak structural plane is obtained and can be expressed as:

[0096]

[0097] When s = 4 mm for this type of weak structural plane, the shear strength is calculated using the traditional Barton formula and the improved formula respectively. The result of the original formula is τ = 3.75 MPa, and the result of the improved formula is τ = 2.8 MPa. By comparison, it can be seen that compared with the traditional formula, this method can not only consider the influence of the thickness of the weak filling on the shear strength of the structural plane, but also consider the weakening effect of the weak filling on the rock mass structural plane, which is more in line with the actual mechanical behavior of the weak structural plane.

[0098] Specifically, the traditional Barton formula has good applicability in calculating the shear strength of rough joints, fissures and other structural planes with filling or little filling, but there are certain deficiencies in the structural planes with soft fillers of a certain thickness. For example, the isolation effect of soft fillers is not considered, the contribution of roughness is overestimated, the contribution of the cohesion c of the soft fillers themselves to the shear strength of the structural plane is not considered, and there is also a lack of quantitative relationship between the thickness of the soft fillers and the attenuation of roughness. Therefore, the shear strength of the structural plane predicted by this method often has a large deviation from the actual situation. Therefore, in order to improve the prediction accuracy of the shear strength of soft structural planes, a reduction coefficient k is introduced to quantify the weakening effect of the thickness of soft fillers on the friction angle increment of roughness, and according to the energy conservation during the shear process of the structural plane, a scale parameter characteristic dissipation thickness s0 representing the energy dissipation efficiency of soft fillers is introduced to construct a quadratic exponential decay calculation model of the reduction coefficient k. Finally, the characteristic dissipation thickness s0 is calibrated using experimental parameters to construct the final calculation model. The improved calculation model reverts to the original Barton formula when there is no filler (s = 0), ensuring the theoretical continuity and achieving compatibility with the traditional model. At the same time, it well solves the defects of the traditional model, providing an important theoretical basis for the prediction of the shear strength of such soft structural planes.

[0099] Aiming at the deficiencies of the traditional Barton formula in calculating the shear strength of soft structural planes, based on the contact theory and the principle of energy conservation during the shear process, a reduction coefficient k and a characteristic dissipation thickness s0 are introduced, and an improved model is proposed. By coupling the self-strength of the filler and the attenuation effect of roughness, a comprehensive shear strength calculation method for structural planes with soft interlayers is formed, which can not only reflect the weakening effect of soft fillers on the rock mass structural plane, but also accurately quantify the relationship between the thickness of soft fillers and the attenuation of the rock wall roughness, and achieve compatibility with the traditional model. This method effectively improves the applicability, reliability and accuracy of the prediction of the shear strength of soft structural planes, provides reliable input for slope stability calculation and support design, effectively reduces the engineering design risk, and improves the engineering safety.

[0100] Example 2: The embodiment of the present application provides a system for calculating the shear strength of a soft structural plane based on the Barton formula, as Figure 2 shown, including:

[0101] The first module is used to introduce a reduction coefficient into the traditional Barton formula and construct an improved Barton formula;

[0102] The second module is used to calculate the shear strength of the soft structural plane by using the improved Barton formula.

[0103] Furthermore, the above-mentioned improved Barton formula is specifically:

[0104]

[0105] In the formula, τ represents the shear strength of the weak structural plane, and σ n is the normal stress acting on the weak structural plane, and φ fill represents the internal friction angle of the weak filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, c represents the cohesion of the weak filling;

[0106] Furthermore, the reduction coefficient in this system is obtained in the following way:

[0107]

[0108] In the formula, k represents the reduction coefficient, s represents the thickness of the filling in the weak structural plane, and s o represents the characteristic dissipation thickness

[0109] Furthermore, the characteristic dissipation thickness in this system is determined in the following way:

[0110] Fabricate structural specimens with different thicknesses of weak filling, and ensure that the filling is evenly distributed and in good contact with the rock wall;

[0111] Use direct shear tests to obtain the shear strength parameters of the weak filling. The shear strength parameters include cohesion and internal friction angle. Obtain the joint roughness coefficient by comparing with the standard roughness profile diagram, and obtain the compressive strength of the joint wall through uniaxial compressive strength tests on rocks;

[0112] Conduct direct shear tests on the structural specimens with different thicknesses of weak filling, and record the peak shear strength;

[0113] Calculate the reduction coefficient according to the data of each structural specimen obtained from the tests;

[0114] Conduct linear regression fitting on each group of reduction coefficients and each group of weak filling thicknesses, and obtain the characteristic dissipation thickness according to the fitting slope.

[0115] Furthermore, calculating the reduction coefficient according to the data of each structural specimen obtained from the tests in the above system is specifically as follows: [[ID=4S0]]

[0116]

[0117] In the formula, σ n is the normal stress acting on the weak structural plane, and φ fill represents the internal friction angle of the weak filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, c represents the cohesion of the weak filling, and τ represents the peak shear strength.

[0118] Embodiment 3: An embodiment of the present application provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the method of Embodiment 1 is implemented.

[0119] Embodiment 4: An embodiment of the present application provides a non-transitory computer-readable storage medium. The non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the method of Embodiment 1.

[0120] The above specific implementation manners further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are only specific implementation manners of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for calculating the shear strength of a weak structural plane based on the Barton formula, characterized in that, It includes the following specific steps: Introduce a reduction coefficient into the traditional Barton formula and construct an improved Barton formula; Calculate the shear strength of the weak structural plane through the improved Barton formula.

2. The method for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 1, wherein The specific form of the improved Barton formula is: Where τ represents the shear strength of the weak structural plane, and σ n is the normal stress acting on the weak structural plane, and φ fill represents the internal friction angle of the weak filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, and c represents the cohesion of the weak filling.

3. A method for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 1 or 2, characterized in that The reduction coefficient is obtained through the following method: where k represents the reduction coefficient, s represents the thickness of the filling material of the weak structural plane, and s o represents the characteristic dissipation thickness.

4. A method for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 3, characterized in that, The characteristic dissipation thickness is determined through the following method: Fabricate structural specimens with different thicknesses of weak fillers, and ensure that the fillers are evenly distributed and in good contact with the rock wall; Use direct shear tests to obtain the shear strength parameters of the weak fillers. The shear strength parameters include cohesion and internal friction angle. Obtain the joint roughness coefficient by comparing with the standard roughness profile diagram, and obtain the joint wall compressive strength through rock uniaxial compressive strength tests; Conduct direct shear tests on the structural specimens with different thicknesses of weak fillers and record the peak shear strength; Calculate the reduction coefficient according to the data of each structural specimen obtained from the tests; Perform linear regression fitting on each group of reduction coefficients and each group of weak filler thicknesses, and obtain the characteristic dissipation thickness according to the fitting slope.

5. A method for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 4, characterized in that The calculation of the reduction coefficient according to the data of each structural specimen obtained from the tests is specifically: where σ n is the normal stress acting on the weak structural plane, φ fill represents the internal friction angle of the weak filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, c represents the cohesion of the weak filling, and τ represents the peak shear strength.

6. A system for calculating the shear strength of a weak structural plane based on the Barton formula, characterized in that, It includes: A first module for introducing a reduction coefficient into the traditional Barton formula and constructing an improved Barton formula; A second module for calculating the shear strength of the weak structural plane through the improved Barton formula.

7. A system for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 6, characterized in that The specific form of the improved Barton formula is: where τ represents the shear strength of the weak structural plane, σ n is the normal stress acting on the weak structural plane, and φ fill represents the internal friction angle of the weak filling; JRC is the joint roughness coefficient; JCS is the compressive strength of the joint wall, k represents the reduction coefficient, and c represents the cohesion of the weak filling; The reduction coefficient in this system is obtained through the following method: where k represents the reduction coefficient, s represents the thickness of the filling material of the weak structural plane, and s o represents the characteristic dissipation thickness.

8. A system for calculating the shear strength of a weak structural plane based on the Barton formula according to claim 7, characterized in that The characteristic dissipation thickness in this system is determined through the following method: Fabricate structural specimens with different thicknesses of weak fillers, and ensure that the fillers are evenly distributed and in good contact with the rock wall; Use direct shear tests to obtain the shear strength parameters of the weak fillers. The shear strength parameters include cohesion and internal friction angle. Obtain the joint roughness coefficient by comparing with the standard roughness profile diagram, and obtain the joint wall compressive strength through rock uniaxial compressive strength tests; Conduct direct shear tests on the structural specimens with different thicknesses of weak fillers and record the peak shear strength; Calculate the reduction coefficient according to the data of each structural specimen obtained from the tests; Perform linear regression fitting on each group of reduction coefficients and each group of weak filler thicknesses, and obtain the characteristic dissipation thickness according to the fitting slope.

9. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the method described in any one of claims 1-5.

10. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the method described in any one of claims 1-5.

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