CN111238965A - Direct shear test device with controllable orthogonal stress state and test method - Google Patents
Direct shear test device with controllable orthogonal stress state and test method Download PDFInfo
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- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0026—Combination of several types of applied forces
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- 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
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- G01N2203/0208—Specific programs of loading, e.g. incremental loading or pre-loading
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Abstract
The invention belongs to the technical field of civil engineering, hydraulic and hydroelectric engineering and new energy engineering, and particularly relates to a direct shear test device with a controllable orthogonal stress state and a test method. The invention is formed by organically combining a circular upper shearing box, a circular lower shearing box, a sliding mechanism connected below the lower shearing box, a horizontal loading device, a fixing device, a vertical loading assembly, a confining pressure control device and a water permeable mechanism. According to the actual stress state of the rock-soil mass, the normal pressure and the lateral confining pressure bidirectional stress of the sample are regulated and controlled, so that the rock-soil mass is subjected to drainage consolidation under the original existing stress state. The invention solves the problem that the traditional direct shear test device and method cannot consider the regulation and control of the confining pressure and can restore the real stress state of the sample as much as possible. The invention can dynamically regulate and control the lateral confining pressure of the sample, more truly obtain the shear strength parameter of the rock-soil body and provide more detailed and accurate basis for the analysis of the engineering safety and stability.
Description
Technical Field
The invention belongs to the technical field of civil engineering, hydraulic and hydroelectric engineering and new energy engineering, and particularly relates to a direct shear test device with a controllable orthogonal stress state and a test method.
Background
At present, the number of high-rise and super high-rise buildings in urban construction is increasing, and the safety and stability of the buildings are more important. Hydraulic engineering, buildings, dams, bank slopes, retaining walls and high-rise buildings can bear certain load, and are closely related to the shear strength of soil. The shear strength of soil is one of the important mechanical property indexes of soil, which refers to the ultimate ability of soil body to resist shear failure, the value is equal to the shear stress when the soil body is subjected to shear failure, and the essence of soil body failure is shear failure.
At present, the shearing property of soil is obtained by performing a direct shearing test by using a shearing instrument. In a general direct shear test, a soil sample is placed in a fixed upper box and a movable lower box of a direct shear apparatus. During the test, vertical pressure is firstly applied to the soil sample, then horizontal thrust is applied to the lower box, and the soil sample is sheared and damaged due to the dislocation between the upper box and the lower box.
However, in an actual complex rock-soil environment, the shear strength parameter of the rock-soil mass is significantly influenced by the stress state of the rock-soil mass, and the traditional direct shear test device and method do not consider the original occurrence stress state of the rock-soil mass and the influence of confining pressure during a shear test, so that the obtained shear strength parameter and test result have larger difference from the actual situation, and the application to the engineering practice may cause larger economic cost waste or larger safety risk.
Disclosure of Invention
The invention provides a direct shear test device with controllable orthogonal stress state and a test method, and aims to provide a direct shear test device with high safety and reliability and low cost and a test method.
In order to achieve the purpose, the invention adopts the technical scheme that:
a direct shear test device with controllable orthogonal stress state comprises
The shearing box is a circular box body consisting of an upper shearing box and a lower shearing box which are arranged up and down, and a circular cavity is formed in the shearing box;
the sliding mechanism is connected with the lower bottom surface of the lower shearing box in a sliding manner;
the horizontal loading device is connected to the outer side wall of the lower shearing box;
the fixing device is connected to the outer side wall of the upper shearing box on the opposite side of the horizontal loading device;
the vertical loading assembly is arranged at the top of the upper shearing box;
the confining pressure control device is connected to the side walls of the upper shearing box and the lower shearing box;
the water permeable mechanism is arranged in the shearing box.
The water permeable mechanism is composed of two permeable stones; one of them permeable stone setting is on shearing box bottom surface down, and another permeable stone setting is at vertical loading subassembly lower surface.
The water permeable mechanism also comprises a drain hole; the drain hole is a blind hole or a through hole and is arranged on the bottom surface of the lower shearing box.
The sliding mechanism consists of a plurality of pulleys; the pulleys are uniformly distributed on the lower bottom surface of the lower shearing box.
The vertical loading assembly comprises a pressurizing piston and a force transmission steel ball; the force transmission steel ball is arranged in the center of the upper surface of the pressurizing piston.
The two confining pressure control devices are respectively connected with the side walls of the upper shearing box and the lower shearing box; the confining pressure control device comprises an air bag, a pressure control valve and an instrument panel; the gasbag is cyclic annular, sets up in last shearing box and the lower shearing box and with last shearing box and the contact of shearing box inner wall down, pressure control valve one end is connected with the panel board, and the pressure control valve other end passes shearing box lateral wall and gasbag intercommunication.
A rigid cushion block is arranged between the air bags of the upper shearing box and the lower shearing box.
The fixing device is a force measuring steel ring.
The upper shearing box is of a circular frame-shaped structure without a cover and a bottom; the lower cutting box is of a box body structure without a cover.
A test method of a direct shear test device with controllable orthogonal stress state comprises the following steps
The method comprises the following steps: cutting an undisturbed soil sample from an engineering site;
step two: after the upper shearing box and the lower shearing box are connected, the upper shearing box and the lower shearing box are fixed with the vertical platform through a force measuring steel ring;
step three: placing the sample in a shearing box, regulating and controlling the lateral confining pressure of the sample through air bags in an upper shearing box and a lower shearing box, and regulating and controlling the normal pressure of the sample through a vertical loading assembly, so that the sample is subjected to drainage consolidation under the original stress state;
step four: after the third step is finished, the lateral confining pressure of the sample is regulated and controlled to be consistent with the actual lateral surrounding rock change state of the sample in the engineering by dynamically regulating the pressure in the air bag, and the set vertical pressure sigma is applied by the vertical loading mechanism(1)And then a horizontal loading device is used for applying a shearing force tau to the test(1)fShearing the test at a set shearing rate until the test is broken;
step four: repeating the first step to the third step, and carrying out at least 4 groups of shear tests to obtain the vertical pressure sigma of at least four groups of tests(1)、σ(2)、σ(3)、σ(4)And four sets of shear forces τ(1)f、τ(2)f、 τ(3)f、τ(4)f；
Step five: and D, according to the vertical pressure and the shear force value of the test obtained in the step four, combining a coulomb strength theory to obtain a shear strength curve, so that the shear strength index of the soil is determined: internal friction angle
And cohesion c;
step six: and determining the resistance of the soil body to shearing damage according to the relation between the cohesive force c and the friction angle phi obtained in the step five.
Has the advantages that:
(1) according to the actual stress state of the rock-soil body, the normal pressure and the lateral confining pressure bidirectional stress of the sample are regulated and controlled, so that the sample is subjected to drainage consolidation under the original existing stress state. Because the rock-soil body has lateral surrounding rock pressure, the device and the method solve the problem that the regulation and control of the surrounding pressure cannot be considered in the traditional direct shear test device and method.
(2) The invention can simulate the conditions of each main stress path of the sample as real as possible and restore the real stress state of the sample.
(3) In the direct shear test process, the lateral confining pressure of the sample can be dynamically regulated and controlled, so that the defect that the lateral confining pressure cannot be controlled in the vertical pressure application process in the traditional direct shear test can be avoided.
(4) The test device and the test method can more truly obtain the shear strength parameters of the rock-soil body due to the reduction of the true stress state, and provide more detailed and accurate basis for the analysis of the engineering safety and stability.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to clearly understand the technical solutions of the present invention and to implement the technical solutions according to the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic longitudinal section of the structure of the present invention;
FIG. 2 is a schematic cross-sectional view of an upper shear box of the present invention;
FIG. 3 is a schematic view of the shear strength line of the present invention.
In the figure: 1-upper cutting box; 2-lower cutting box; 3-vertical loading component; 4-permeable stone; 5-horizontal loading device; 6-a drain hole; 7-a pulley; 8-a pressurizing piston; 9-force transmission steel balls; 10-air bag; 11-a pressure control valve; 12-instrument panel; 13-force measuring steel ring; 14-sample; 15-a vertical platform; 16-rigid spacer blocks.
Detailed Description
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, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of protection of the present invention.
The first embodiment is as follows:
a direct shear test device with controllable orthogonal stress state shown in figures 1 and 2 comprises
The shearing box is a circular box body consisting of an upper shearing box 1 and a lower shearing box 2 which are arranged up and down, and a circular cavity is formed in the shearing box;
the sliding mechanism is connected with the lower bottom surface of the lower shearing box 2 in a sliding manner;
the horizontal loading device 5, the horizontal loading device 5 is connected to the outer side wall of the lower shearing box 2;
the fixing device is connected to the outer side wall of the upper shearing box 1 on the opposite side of the horizontal loading device 5;
the vertical loading assembly 3 is arranged at the top of the upper shearing box 1;
the confining pressure control device is connected to the side walls of the upper shearing box 1 and the lower shearing box 2;
the water permeable mechanism is arranged in the shearing box.
In actual use, firstly cutting an undisturbed soil sample 14 from a project site; after the upper shearing box 1 and the lower shearing box 2 are connected, the upper shearing box and the lower shearing box are fixed with a vertical platform 15 through a force measuring steel ring 13; the sample 14 is then placed in a shear box, the lateral confining pressure of the sample 14 is regulated by the air pockets 10 in the upper shear box 1 and the lower shear box 2, by applying verticallyThe loading component 3 regulates and controls the normal pressure of the sample 14, so that the sample 14 is subjected to drainage consolidation under the original stress state; then dynamically regulating and controlling the lateral confining pressure of the sample 14, and applying a set vertical pressure sigma to the vertical loading mechanism 31Then a horizontal loading device 5 applies a shearing force tau to the test1fShearing the test at a set shearing rate until the step is broken to carry out at least 4 groups of shearing tests to obtain the vertical pressure sigma of at least four groups of tests(1)、σ(2)、σ(3)、 σ(4)And four sets of shear forces τ(1)f、τ(2)f、τ(3)f、τ(4)f(ii) a According to the obtained vertical pressure and shear force values of at least four groups of tests, a shear strength curve (shown in figure 3) is obtained by combining the coulomb strength theory, so that the shear strength index of the soil is determined: internal friction angle
And cohesion c; and obtaining the shear strength parameter of the rock-soil body according to the obtained relation between the cohesive force c and the friction angle phi, and providing a more detailed and accurate basis for engineering safety and stability analysis.
When the horizontal loading device 5 acts, the horizontal loading device translates towards the vertical platform 15 side through the sliding mechanism, so that the accuracy of the test data is ensured.
The invention can regulate and control the normal pressure and the lateral confining pressure bidirectional stress of the sample according to the actual stress state of the rock-soil mass, so that the rock-soil mass is subjected to drainage consolidation under the original stress state. Because the rock-soil body has lateral surrounding rock pressure, the device and the method solve the problem that the regulation and control of the surrounding pressure cannot be considered in the traditional direct shear test device and method. The invention can simulate the conditions of each main stress path of the sample as real as possible and restore the real stress state of the sample. In the direct shear test process, the lateral confining pressure of the test sample can be dynamically regulated and controlled, so that the defect that the lateral confining pressure cannot be controlled in the vertical pressure application process in the traditional direct shear test can be avoided. The test device and the test method can more truly obtain the shear strength parameters of the rock-soil body due to the reduction of the true stress state, and provide more detailed and accurate basis for the analysis of the engineering safety and stability.
Example two:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1, the difference from the first embodiment is that: the water permeable mechanism is composed of two permeable stones 4; one of the permeable stones 4 is arranged on the bottom surface of the lower shearing box 2, and the other permeable stone 4 is arranged on the lower surface of the vertical loading component 3.
Preferably, the water permeable mechanism further comprises a drain hole 6; the drain holes 9 are blind holes or through holes and are arranged on the bottom surface of the lower shearing box 2.
In practical use, the water squeezed out in the process of draining and consolidating the sample 14 in the original stress state is absorbed by the permeable stone 4, so that the sample 14 can be consolidated well and quickly.
When the moisture in the sample is not much, only the permeable stone 4 is used for absorbing water, when the moisture contained in the sample 14 is more and the permeable stone 4 cannot meet the requirement, the scheme of the drain hole 9 is used for meeting the requirement, and the excessive moisture absorbed by the permeable stone 4 enters the drain hole 9.
The drain hole 9 is a blind hole or a through hole, and can be selected according to actual needs, when the water absorbed by the permeable stone 4 is more, the through hole can be adopted, otherwise, the blind hole can be adopted.
Example three:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1, the difference from the first embodiment is that: the sliding mechanism consists of a plurality of pulleys 7; the pulleys 7 are uniformly distributed on the lower bottom surface of the lower shearing box 2.
When in actual use, the sliding mechanism adopts the technical scheme of the pulleys 7, so that the test requirements can be met, and the cost can be saved. In specific application, the sliding mechanism can also adopt a plurality of modes such as a sliding rail and the like. Any device that can move the shear box smoothly may be used.
Example four:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1, the difference from the first embodiment is that: the vertical loading assembly 3 comprises a pressurizing piston 8; the force transmission steel ball 9 is arranged in the center of the upper surface of the pressurizing piston 8.
In actual use, external force is applied to the vertical loading assembly 3 and is transmitted to the sample 14 through the force transmission steel ball 9 and the pressurizing piston 8. By adopting the technical scheme of transferring force through the force transferring steel balls 9, the force applied to the sample 14 is ensured to be always kept normal force.
Example five:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1 and fig. 2, the difference from the first embodiment is that: the two confining pressure control devices are respectively connected with the side walls of the upper shearing box 1 and the lower shearing box 2; the confining pressure control device comprises an air bag 10, a pressure control valve 11 and an instrument panel 12; the gasbag 10 is cyclic annular, set up in last shearing box 1 and lower shearing box 2 and with last shearing box 1 and the contact of 2 inside walls of lower shearing box, 11 one end of pressure control valve is connected with panel board 12, and 11 other ends of pressure control valve pass and cut box lateral wall and gasbag 10 intercommunication.
In actual use, the external inflating device inflates the air bag 10, the air bag 10 is inflated to meet a preset standard, and the pressure control valve 11 is closed to perform subsequent tests.
The invention adopts the technical scheme to adjust the confining pressure, and is convenient and economical.
Example six:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1 and fig. 2, the difference from the first embodiment is that: a rigid cushion block 16 is arranged between the air bags 10 of the upper shear box 1 and the lower shear box 2.
In actual use, the rigid cushion 16 is arranged between the air bags 10 of the upper shear box 1 and the lower shear box 2, so as to avoid the mutual influence of the air bags 10 in the upper shear box 1 and the lower shear box 2 and further influence the final test result. The rigid pad 16 is selected to ensure that it does not deform under predetermined pressure conditions.
Example seven:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1, the difference from the first embodiment is that: the fixing device is a force measuring steel ring 13.
During the actual use, the shear box is connected fixedly with vertical platform 15 through power measuring steel ring 13, guarantees the stability of shear box in the testing process. The force measuring steel ring 13 adopts the prior art.
Example eight:
according to the direct shear test device with controllable orthogonal stress state shown in fig. 1, the difference from the first embodiment is that: the upper shearing box 1 is of a circular frame-shaped structure without a cover and a bottom; the lower cutting box 2 is of a box body structure without a cover.
When the device is actually used, the upper shearing box 1 and the lower shearing box 2 adopt the technical scheme of a circular frame-shaped structure, so that the regulation and control of lateral confining pressure can be simplified, and the device is suitable for most geological conditions on site.
Example nine:
a test method of a direct shear test device with controllable orthogonal stress state comprises the following steps
The method comprises the following steps: cutting an undisturbed soil sample 14 from a project site;
step two: after the upper shearing box 1 and the lower shearing box 2 are connected, the upper shearing box and the lower shearing box are fixed with a vertical platform 15 through a force measuring steel ring 13;
step three: placing a sample 14 in a shearing box, regulating and controlling the lateral confining pressure of the sample 14 through air bags 10 in an upper shearing box 1 and a lower shearing box 2, and regulating and controlling the normal pressure of the sample 14 through a vertical loading assembly 3, so that the sample 14 is subjected to drainage consolidation under the original stress state;
step four: after the third step is finished, the lateral confining pressure of the sample 14 is regulated and controlled to be consistent with the actual lateral surrounding rock change state of the sample 14 in the engineering by dynamically adjusting the pressure in the air bag 10, and the set vertical pressure sigma is applied to the loading mechanism 3 vertically1And then a horizontal loading device 5 applies a shearing force tau to the test1fShearing the test at a set shearing rate until the test is broken;
step four: repeating the first step to the third stepPerforming at least 4 sets of shear tests to obtain vertical pressure sigma of at least four sets of tests(1)、σ(2)、σ(3)、σ(4)And four sets of shear forces τ(1)f、τ(2)f、 τ(3)f、τ(4)f；
Step five: and D, according to the vertical pressure and the shear force value of the test obtained in the step four, combining a coulomb strength theory to obtain a shear strength curve, so that the shear strength index of the soil is determined: internal friction angle
And cohesion c;
step six: and determining the resistance of the soil body to shearing damage according to the relation between the cohesive force c and the friction angle phi obtained in the step five.
According to the test method, the normal pressure and the lateral confining pressure bidirectional stress of the sample are regulated and controlled according to the actual stress state of the rock-soil body, so that the sample is subjected to drainage consolidation under the original stress state. Because the rock-soil body has lateral surrounding rock pressure, the device and the method solve the problem that the regulation and control of the surrounding pressure cannot be considered in the traditional direct shear test device and method. The invention can simulate the conditions of each main stress path of the sample as real as possible and restore the real stress state of the sample. In the direct shear test process, the lateral confining pressure of the sample can be dynamically regulated and controlled, so that the defect that the lateral confining pressure cannot be controlled in the vertical pressure application process in the traditional direct shear test can be avoided. The test device and the method can more truly obtain the shear strength parameters of the rock-soil body (as shown in figure 3) due to the reduction of the true stress state, and provide more detailed and accurate basis for the analysis of the engineering safety and stability.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that are within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
In the case of no conflict, those skilled in the art may combine the related technical features in the above examples according to actual situations to achieve corresponding technical effects, and specific details of various combining situations are not described herein.
It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.
The foregoing is illustrative of the preferred embodiments of the present invention, and the present invention is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Any simple modification, equivalent change and modification of the above embodiments according to the technical spirit of the present invention still fall within the scope of the technical solution of the present invention.
Claims (10)
1. The utility model provides a controllable direct shear test device of quadrature stress state which characterized in that: comprises that
The shearing box is a circular box body consisting of an upper shearing box (1) and a lower shearing box (2) which are arranged up and down, and a circular cavity is formed in the shearing box;
the sliding mechanism is connected with the lower bottom surface of the lower shearing box (2) in a sliding manner;
the horizontal loading device (5), the horizontal loading device (5) is connected to the outer side wall of the lower shearing box (2);
the fixing device is connected to the outer side wall of the upper shearing box (1) on the opposite side of the horizontal loading device (5);
the vertical loading assembly (3), the vertical loading assembly (3) is arranged at the top of the upper shearing box (1);
the confining pressure control device is connected to the side walls of the upper shearing box (1) and the lower shearing box (2);
the water permeable mechanism is arranged in the shearing box.
2. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the water permeable mechanism is composed of two permeable stones (4); one of the permeable stones (4) is arranged on the bottom surface of the lower shearing box (2), and the other permeable stone (4) is arranged on the lower surface of the vertical loading component (3).
3. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 2, wherein: the water permeable mechanism also comprises a drain hole (6); the drain holes (9) are blind holes or through holes and are arranged on the bottom surface of the lower shearing box (2).
4. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the sliding mechanism consists of a plurality of pulleys (7); the pulleys (7) are uniformly distributed on the lower bottom surface of the lower shearing box (2).
5. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the vertical loading assembly (3) comprises a pressurizing piston (8) and a force transmission steel ball (9); the force transmission steel ball (9) is arranged in the center of the upper surface of the pressurizing piston (8).
6. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the two confining pressure control devices are respectively connected with the side walls of the upper shearing box (1) and the lower shearing box (2); the confining pressure control device comprises an air bag (10), a pressure control valve (11) and an instrument panel (12); gasbag (10) are cyclic annular, set up in last shearing box (1) and lower shearing box (2) and with last shearing box (1) and the contact of lower shearing box (2) inside wall, pressure control valve (11) one end is connected with panel board (12), and pressure control valve (11) other end passes and cuts box lateral wall and gasbag (10) intercommunication.
7. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 6, wherein: a rigid cushion block (16) is arranged between the air bags (10) of the upper shearing box (1) and the lower shearing box (2).
8. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the fixing device is a force measuring steel ring (13).
9. A direct shear test apparatus with controllable orthogonal stress state as claimed in claim 1, wherein: the upper shearing box (1) is of a circular frame-shaped structure without a cover and a bottom; the lower cutting box (2) is of a box body structure without a cover.
10. The method for testing a direct shear test apparatus with controllable orthogonal stress state according to any one of claims 1 to 9, comprising the steps of
The method comprises the following steps: cutting an undisturbed soil sample (14) from a project site;
step two: after the upper shearing box (1) and the lower shearing box (2) are connected, the upper shearing box and the lower shearing box are fixed with a vertical platform (15) through a force measuring steel ring (13);
step three: placing a sample (14) in a shearing box, regulating and controlling the lateral confining pressure of the sample (14) through air bags (10) in an upper shearing box (1) and a lower shearing box (2), and regulating and controlling the normal pressure of the sample (14) through a vertical loading assembly (3), so that the sample (14) is subjected to drainage consolidation under the original stress state;
step four: after the third step is finished, the lateral confining pressure of the sample (14) is regulated and controlled to be consistent with the actual lateral surrounding rock change state of the sample (14) in the engineering by dynamically regulating the pressure in the air bag (10), and the set vertical pressure sigma is applied to the loading mechanism (3) vertically(1)Then a horizontal loading device (5) is used for applying a shearing force tau to the test(1)fShearing the test at a set shearing rate until the test is broken;
step four: repeating the first step to the third step, and carrying out at least 4 groups of shear tests to obtain the vertical pressure sigma of at least four groups of tests(1)、σ(2)、σ(3)、σ(4)And four sets of shear forces τ(1)f、τ(2)f、τ(3)f、τ(4)f；
Step five:and D, according to the vertical pressure and the shear force value of the test obtained in the step four, combining a coulomb strength theory to obtain a shear strength curve, so that the shear strength index of the soil is determined: internal friction angle
And cohesion c;
step six: and determining the resistance of the soil body to shearing damage according to the relation between the cohesive force c and the friction angle phi obtained in the step five.
Priority Applications (1)
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111896446A (en) * | 2020-07-09 | 2020-11-06 | 河海大学 | Contact surface shear seepage test device and test method considering temperature effect |
| CN113686695A (en) * | 2021-07-27 | 2021-11-23 | 中国科学院武汉岩土力学研究所 | Rock friction test device |
| CN113776959A (en) * | 2021-08-18 | 2021-12-10 | 中国地质大学（武汉） | Slip band soil shearing-seepage coupling test device and use method thereof |
| CN114739785A (en) * | 2022-04-14 | 2022-07-12 | 中国电建集团西北勘测设计研究院有限公司 | Direct shear peak value and residual strength testing device and method for grading unloading of rock and soil mass |
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2020
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111896446A (en) * | 2020-07-09 | 2020-11-06 | 河海大学 | Contact surface shear seepage test device and test method considering temperature effect |
| CN113686695A (en) * | 2021-07-27 | 2021-11-23 | 中国科学院武汉岩土力学研究所 | Rock friction test device |
| CN113776959A (en) * | 2021-08-18 | 2021-12-10 | 中国地质大学（武汉） | Slip band soil shearing-seepage coupling test device and use method thereof |
| CN114739785A (en) * | 2022-04-14 | 2022-07-12 | 中国电建集团西北勘测设计研究院有限公司 | Direct shear peak value and residual strength testing device and method for grading unloading of rock and soil mass |
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