GB2624982A - Method for determining angle of internal friction of soft rock - Google Patents
Method for determining angle of internal friction of soft rock Download PDFInfo
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- GB2624982A GB2624982A GB2319807.0A GB202319807A GB2624982A GB 2624982 A GB2624982 A GB 2624982A GB 202319807 A GB202319807 A GB 202319807A GB 2624982 A GB2624982 A GB 2624982A
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- 239000011435 rock Substances 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000012360 testing method Methods 0.000 claims abstract description 31
- 238000012669 compression test Methods 0.000 claims abstract description 17
- 238000012545 processing Methods 0.000 claims abstract description 11
- 238000005553 drilling Methods 0.000 claims abstract description 7
- 238000012512 characterization method Methods 0.000 claims abstract description 5
- 238000004364 calculation method Methods 0.000 claims description 8
- 239000012528 membrane Substances 0.000 claims description 3
- 239000002689 soil Substances 0.000 description 6
- 230000003068 static effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 239000004927 clay Substances 0.000 description 2
- 239000002734 clay mineral Substances 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 230000009545 invasion Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/24—Investigating strength properties of solid materials by application of mechanical stress by applying steady shearing forces
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
- G01N3/18—Performing tests at high or low temperatures
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/06—Special adaptations of indicating or recording means
- G01N3/068—Special adaptations of indicating or recording means with optical indicating or recording means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/0003—Steady
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0025—Shearing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/022—Environment of the test
- G01N2203/0222—Temperature
- G01N2203/0228—Low temperature; Cooling means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/022—Environment of the test
- G01N2203/023—Pressure
- G01N2203/0232—High pressure
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/0641—Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
- G01N2203/0647—Image analysis
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
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- Biochemistry (AREA)
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Abstract
A method for determining the angle of internal friction of soft rock, comprising: first drilling undisturbed soft rock by means of a small-diameter core barrel, carrying out a triaxial compression test on the undisturbed soft rock on the basis of a high-pressure low-temperature hydrate triaxial test system, collecting an image of a failure surface of the test sample, performing characterization processing on the basis of PicPick digital image processing software so as to acquire a rupture angle, and finally determining the angle of internal friction according to a relational expression between the rupture angle and the angle of internal friction. The method is simple and convenient to operate, and can directly obtain the rupture angle at a higher precision without a large number of tests and without reading test data and carrying out a fitting process.
Description
METHOD FOR DETERMINING ANGLE OF INTERNAL FRICTION OF SOFT
ROCK
[0001] The present application claims the priority to Chinese Patent Application No. 202210731352.9 filed to China National Intellectual Property Administration on Jun. 24, 2022 and entitled "Method for determining angle of internal friction of soft rock", which is incorporated in its entirety herein by reference.
TECHNICAL FIELD
[0002] The present disclosure belongs to the technical field of shear strength parameter measurement of soft rocks in geotechnical engineering, and relates to a method for determining an angle of internal friction of a soft rock.
BACKGROUND ART
[0003] Shear strength refers to the ultimate ability of a rock-soil body to resist shear damage caused by external forces, which is an important index for evaluating the mechanical properties of the rock-soil body. According to the Mohr-Coulomb strength theory, shear strength can be divided into friction strength and cohesion strength. However, as a special rock, a soft rock has a microscopic structure and engineering properties that are different from a soil body and a hard rock. There are clay minerals and pore defects inside the soft rock. The composition of clay minerals and pore defects have a great influence on the contact friction properties between the particle skeletons of the mineral in soft rock. Friction between skeleton particles includes kinetic friction and static friction which do not occur independently. Dynamic friction and static friction occur one after another during the friction process. This complex friction property is macroscopically manifested as friction intensity. The angle of internal friction cp is an index parameter that reflects the friction intensity. Therefore, to reasonably and accurately measure the angle of internal friction cp of the soft rock is a key link Accurate measurement of the angle of internal friction cp helps to analyze the strength characteristics of the soft rock, which is an important support for theoretical analysis, design calculation, and engineering application of the soft rock, as well as numerical simulation and other work.
[0004] At present, methods for acquiring mechanical parameters of the rock body include an experimental method, an inversion calculation method, an "Engineering Rock Body Quality Grading Standards" method, an engineering analogy method, and the like. Among them, the experimental method is the main method to obtain the real mechanical parameters of the rock body. At the same time, the experimental method is also the basis of other methods. Compared with field tests, indoor tests have the advantages of simple operation and short time consumption. Therefore, conventional triaxial compression tests are carried out. According to the Mohr-Coulomb criterion, the shear strength parameters are obtained through the Mohr circle envelope, which is a common channel for determining the angle of internal friction (p. However, the triaxial test result is processed according to the Mohr-Coulomb criterion. As a result, the process of calculating the angle of internal friction cp is also cumbersome. Aiming at this problem, the prior art CN201510435511.0 discloses a method of measuring cohesion c and angle of internal friction cp of a rock using nails. However, establishment of a relationship between nail penetration and shear strength parameters requires a large number of triaxial tests, and the uneven and weak interlayer in soft rock will affect the amount of nail penetration. CN201310145434.6 discloses a method of acquiring shear strength parameters of a soil body through cross plate in-situ testing, but this method is suitable for clay soil with high sensitivity, and has limitations for soft rocks with higher strength and hardness. Therefore, a convenient and scientific method for determining the angle of internal friction (p of a soft rock is urgently needed.
SUMMARY
[0005] In view of the shortcomings in the prior art, the present disclosure is designed to provide a convenient and scientific method for determining the angle of internal friction of a soft rock, including the following steps: first, drilling an original soft rock by a selected core barrel with a small diameter; carrying out a triaxial compression test on the original soft rock based on a triaxial test system with high-pressure and low-temperature hydrate; then acquiring an image of a fracture surface of a sample and performing characterization processing based on PicPick digital image processing software to obtain an angle of fracture; and finally, determining the angle of internal friction based on a relational expression between the angle of fracture and the angle of internal friction.
[0006] In order to achieve the above object, the specific process of determining the angle of internal friction of the soft rock in the present disclosure includes the following steps: [0007] drilling an original soft rock: drilling an original soft rock by a small-diameter drill bit with a diameter of 75 mm and a core barrel with a diameter of 73 mm, so as to obtain the original soft rock with the diameter of 50 mm and meeting requirements of uniaxial compressive strength and of diameter in triaxial compression test; [0008] processing samples: carving the original soft rock by a selected art carving knife, grinding the original soft rock off by a sharp-tooth wire saw, and repeating the carving and grinding until a height of the original soft rock meets standard size of sample, and numbering each sample; [0009] carrying out a triaxial compression test: after a surface of the sample is covered with a rubber membrane, placing the samples in a pressure chamber of a triaxial testing system with high-pressure and low-temperature hydrate, carrying out a triaxial compression test on the original soft rock, wherein two parallel tests are carried out at a same level of confining pressure; [0010] acquiring an image of a fracture surface: after the triaxial compression test is completed, taking out a damaged sample, placing all damaged samples flatly on a work surface, and acquiring an image of a fracture surface of each damaged sample by a digital camera perpendicular to the fracture surface; [0011] performing characterization processing to obtain an angle of fracture: processing the image of the fracture surface of each damaged sample by PicPick digital image software, and characterizing the image of the fracture surface to obtain the angle of fracture aj between the fracture surface and a large principal stress action surface of each damaged sample; and [0012] calculating an angle of internal friction: according to a relationship between the angle of fracture of and the angle of internal friction co: a (1) [0013] obtaining a calculation equation for the angle of internal friction: 4Y) (2) [0014] and obtaining the angle of internal friction cp of the soft rock according to the equation (2).
[0015] The static triaxial test system with high-pressure and low-temperature hydrate of the present disclosure is produced by the British GDS Company, with the model of ETAS, the maximum confining pressure of 32 MPa and the maximum axial force of 100 kN.
[0016] Compared with the prior art, the method of the present disclosure is simple, easy to operate, does not require a large number of tests, and highly accurate in the determined angle of internal friction. For the soft rock, the method for measuring the angle of internal friction using the Mohr circle envelope is affected by the accuracy and test data of the triaxial instrument, the error of data reading and the degree of discreteness of data fitting restrict the accuracy of the angle of internal friction. Without reading the test data and fitting process, in the present disclosure, the angle of fracture can be obtained directly, with higher accuracy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Fig. 1 is a specific flow chart of the method for determining an angle of internal friction of a soft rock according to the present disclosure; [0018] Fig. 2 is a diagram of the drilling process of mud rock according to an embodiment of the present disclosure; [0019] Fig. 3 shows partial mud rock samples according to an embodiment of the present disclosure; [0020] Fig. 4 is a process diagram of the triaxial compression test on the mud rock according to an embodiment of the present disclosure; [0021] Fig. 5 is a stress-strain curve of the triaxial test on the mud rock according to an embodiment of the present disclosure, where (a) is the first group of samples, and (b) is the second group of samples; [0022] Fig. 6 is acquired images of the fracture surfaces of the samples according to an embodiment of the present disclosure, where (a)-(h) in the figures arc samples 1-1-1, 1-1-2. 1-1-3, 1-1-4, 1-2-1 2-1-2, 2-1-4. 2-2-2, and 2-2-3 in sequence; and [0023] Fig. 7 is a process diagram for acquiring the angle of fracture ai according to an embodiment of the present disclosure, where (a)-(h) in the figures are samples 1-1-1, 1-1-2, 1-1-3, 1-1-4, 1-2-3, 2-1-2, 2-1-4, 2-2-2, and 2-2-3 in sequence.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] The present disclosure will be further described below through specific embodiments and in conjunction with the accompanying drawings.
[0025] Embodiment 1: [0026] The specific process for determining the angle of internal friction according to an embodiment includes the following steps: 100271 (1) Drilling an original mud rock: [0028] Since the mud rock is easily disturbed, there is a phenomenon of disintegration and destruction in the prepared sample. In order to avoid the disturbance caused by the traditional large-dituneter core sample production to generate errors in the calculation of the angle of internal friction, a small-diameter drill bit with the diameter of 75 mm and a core barrel with the diameter of 73 mm that are rarely used by survey units are selected, such that the diameter of the original core taken out is exactly 50 mm, which meets the requirements of uniaxial compressive strength and of diameter in triaxial compression test.
[0029] (2) Processing samples: [0030] Considering that the cutting and grinding process for ordinary rocks is not suitable for easily disturbed soft rocks, at the same time, the hardness of the mud rock is relatively large, and the earth-cutting knives and ordinary wire saws for clay soil sample preparation are not suitable, the mud rock is carved with an art carving knife bit by bit, and is gently ground by a sharp-toothed wire saw. The operations are repeated until the height of the original rock core meets the standard sample size, and each sample is numbered. This test has two groups, the first group:1-1-1, 1-1-2, 1-1-3, 1-1-4, 1-2-1, 1-2-2, 1-2-3, and 1-2-4; the second group: 2-1-1, 2-1-2, 2-1-3, 2-1-4, 2-2-1, 2-2-2, 2-2-3, and 2-2-4; two parallel tests carried out on each group correspond to the confining pressures of 0.5 MPa. 1.0 MPa. 1.5 MPa, and 2.0 MPa, respectively, and the more ideal result is taken.
[0031] (3) Carrying out a triaxial compression test: [0032] Since the conventional rock triaxial instrument has higher level of pressure, but the strength of mud rock is lower, so the sample was damaged before displaying a stable reading, and the accuracy is insufficient. Therefore, a static triaxial test system with high-pressure and low-temperature hydrate having a level of pressure between that of the conventional rock triaxial instrument and a geotechnical triaxial instrument is used, which is produced by the British GDS Company, with the model of ETAS, the maximum confining pressure of 32 MPa and the maximum axial force of 100kN. A standard triaxial test, a stress path test and a Ko cementing test can be carried out on the system, which meet the requirements of the test in the embodiment. To prevent invasion of pressurized medium liquid oil into the pressure chamber, the surface of the sample is covered with a rubber membrane, and then the sample is placed in the pressure chamber of the static triaxial test system with high-pressure and low-temperature hydrate to carry out the triaxial compression test on the original muck rock. Due to poor homogeneity of the mud rock, parallel tests arc carried out twice at the same level of confining pressure, and the ideal result is taken. To calculate the angle of internal friction, the samples 1-1-1, 1-1-2, 1-1-3, 1-1-4, and 1-2-3 in the first group and 2-1-2, 2-1-4, 2-2-2, and 2-2-3 are finally selected.
[0033] (4) Acquiring an image of the fracture surface: [0034] After the triaxial compression test is completed, the damaged sample is taken out, and the damaged samples 1-1-1, 1-1-2, 1-1-3, 1-1-4, and 1-2-3 in the first group and 2-1-2, 2-1-4, 2-2-2, and 2-2-3 are all placed flatly on the work surface. A digital camera perpendicular to the fracture surface is used to acquire the image. The images acquired from the fracture surfaces of the damaged samples are as shown in the Fig. 6. [0035] (5) Performing characterization processing to obtain the angle of fracture ay: [0036] PicPick digital image software is used to process the image of the fracture surface of the damaged sample. The principle is equivalent to measuring the angle by a protractor. The image of the fracture surface of the damaged sample is characterized to obtain the angle of fracture af of the damaged sample. The processing process is shown in Fig. 7, and the results are shown in Table 1.
[0037] (6) Calculating the angle of internal friction p: [0038] In the triaxial compression test, the relationship between the angle of fracture af of the fracture surface relative to the large principal stress action surface and the angle of internal friction (p of the sample is: -45 ' (1) [0039] According to the above equation, the calculation equation of the angle of internal friction is obtained: 45>) (2) [0040] The angle of internal friction y9 of the soft rock is calculated based on the angle of fracture af of the fracture surface relative to the large principal stress action surface of the sample obtained in step (5). The results are shown in Table 1.
[0041] Table 1: Statistics table of angle of internal friction (p of mud rock sample (unit: degree) NO. 1 124 244 24,2 2-24 8VaVitile " 5032 1i6 56.7$ 5.$i 5241 795.i034 (4.64 1117 7346 7J7 24.02 2..00 28 [0042] Using the method of determining the angle of internal friction, the angle of internal friction (p of the muck rock is calculated to be 23.2°.
[0043] Embodiment 2: [0044] In the embodiment, the existing Mohr-Coulomb strength criterion method is used to calculate the angle of internal friction y for the sample in the embodiment 1 and the triaxial test results are counted. The geometric relationship between the fracture principal stress line and the Mohr intensity envelope is used. The relationship between the large principal stress ai, the small principal stress (73 and the angle of internal friction y is shown in equation (3): (3) [0045] According to results of the triaxial test, the relationship between the large principal stress (Ti and the small principal stress G3 is fitted to obtain an equation (4) h (4) [0046] In the equation, a and h are the intercept and slope of the fitted straight line respectively to derive equations (5) and (6): (5) (6) [0047] The above two sets of mud rock triaxial test results are calculated from equation (6) as follows: Group 1: ; group 2: and average value: the angle of internal frictions (p of the mud rock measured by the calculation method in the embodiment and embodiment 1 are 21.6° and 23.2° respectively, and the difference between the two is only 6.9%. Comparative verification with the Mohr-Coulomb strength criterion method shows that the method proposed in the embodiment to determine the angle of internal friction of the soft rock is scientific and feasible.
Claims (1)
- WHAT IS CLAIMED IS: 1. A method for determining an angle of internal friction of a soft rock, characterized in that the method comprises: chilling an miginal soft rock: drilling an original soft rock by a small-diameter drill bit with a diameter of 75 mm and a core barrel with a diameter of 73 mm, so as to obtain the original soft rock with the diameter of 50 mm and meeting requirements of uniaxial compressive strength and of diameter in triaxial compression test; processing samples: carving the original soft rock by a selected art carving knife, grinding the original soft rock off by a sharp-tooth wire saw, and repeating the carving and grinding until a height of the original soft rock meets standard size of sample, and numbering each sample; carrying out a triaxial compression test: after a surface of the sample is covered with a rubber membrane, placing the samples in a pressure chamber of a triaxial testing system with high-pressure and low-temperature hydrate, carrying out a triaxial compression test on the original soft rock, wherein two parallel tests are carried out at a same level of confining pressure; acquiring an image of a fracture surface: after the triaxial compression test is completed, taking out a damaged sample, placing all damaged samples flatly on a work surface, and acquiring an image of a fracture surface of each damaged sample by a digital camera perpendicular to the fracture surface; performing characterization processing to obtain an angle of fracture: processing the image of the fracture surface of each damaged sample by PicPick digital image software, and characterizing the image of the fracture surface to obtain the angle of fracture al' between the fracture surface and a large principal stress action surface of each damaged sample; and calculating an angle of internal friction: according to a relationship between the angle of fracture Uf and the angle of internal friction y: obtaining a calculation equation of the angle of internal friction: and obtaining the angle of internal friction yo of the soft rock according to the calculation equation of the angle of internal friction.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210731352.9A CN115266392A (en) | 2022-06-24 | 2022-06-24 | Method for determining internal friction angle of soft rock |
| PCT/CN2023/097672 WO2023246459A1 (en) | 2022-06-24 | 2023-06-01 | Method for determining angle of internal friction of soft rock |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB202319807D0 GB202319807D0 (en) | 2024-02-07 |
| GB2624982A true GB2624982A (en) | 2024-06-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| GB2319807.0A Pending GB2624982A (en) | 2022-06-24 | 2023-06-01 | Method for determining angle of internal friction of soft rock |
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|---|---|
| CN (1) | CN115266392A (en) |
| GB (1) | GB2624982A (en) |
| WO (1) | WO2023246459A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115266392A (en) * | 2022-06-24 | 2022-11-01 | 青岛理工大学 | Method for determining internal friction angle of soft rock |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102645383A (en) * | 2012-04-06 | 2012-08-22 | 中冶集团资源开发有限公司 | Method for measuring shear strength of discontinuous shear plane of rock by utilizing three-shaft compression |
| CN109141960A (en) * | 2018-07-06 | 2019-01-04 | 绍兴文理学院 | A kind of in-situ test method obtaining rock parameter |
| CN112014240A (en) * | 2020-09-01 | 2020-12-01 | 山东科技大学 | Rock mass shearing parameter evaluation method based on in-situ surface single fracture |
| EP3904867A1 (en) * | 2020-04-29 | 2021-11-03 | voestalpine Stahl GmbH | Method and device for determining the break area of a sample |
| CN115266392A (en) * | 2022-06-24 | 2022-11-01 | 青岛理工大学 | Method for determining internal friction angle of soft rock |
-
2022
- 2022-06-24 CN CN202210731352.9A patent/CN115266392A/en active Pending
-
2023
- 2023-06-01 WO PCT/CN2023/097672 patent/WO2023246459A1/en unknown
- 2023-06-01 GB GB2319807.0A patent/GB2624982A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102645383A (en) * | 2012-04-06 | 2012-08-22 | 中冶集团资源开发有限公司 | Method for measuring shear strength of discontinuous shear plane of rock by utilizing three-shaft compression |
| CN109141960A (en) * | 2018-07-06 | 2019-01-04 | 绍兴文理学院 | A kind of in-situ test method obtaining rock parameter |
| EP3904867A1 (en) * | 2020-04-29 | 2021-11-03 | voestalpine Stahl GmbH | Method and device for determining the break area of a sample |
| CN112014240A (en) * | 2020-09-01 | 2020-12-01 | 山东科技大学 | Rock mass shearing parameter evaluation method based on in-situ surface single fracture |
| CN115266392A (en) * | 2022-06-24 | 2022-11-01 | 青岛理工大学 | Method for determining internal friction angle of soft rock |
Non-Patent Citations (2)
| Title |
|---|
| Tan, Fan; Huang, Bin; Rao, Xi-Bao; Zuo, Yong-Zhen, "Experimental Demonstration and Discussion on Rupture Angle in Triaxial Test", Northwestern Seismological Journal, CN, CN, (20110831), vol. 33, no. Suppl. 1, ISSN 1000-0844, pages 181 - 184, [Y] 1 * p. 181, column 2, paragraph 1 to p. 18 * |
| u, Qijun; Cai, Qijie; He, Leping; Yang, Xiaoqiang; Ye, Tao, "Determination of Strength Parameters of Muddy Interlayer Based on Strain Failure Criterion", Gongye Jianzhu, Yejin-bu, China, China , (20160731), vol. 46, no. 7, doi:10.13204/j.gyjz201607024, ISSN 1000-8993, pages 140 - 144, 177, * |
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| Publication number | Publication date |
|---|---|
| GB202319807D0 (en) | 2024-02-07 |
| CN115266392A (en) | 2022-11-01 |
| WO2023246459A1 (en) | 2023-12-28 |
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