CN106198264A - A kind of true triaxial rock adds unloading disturbance experimental provision and using method thereof - Google Patents

Abstract

The invention discloses a true triaxial rock loading and unloading disturbance experiment device, which comprises a vertical loading device and a horizontal loading device, and the vertical loading device and the horizontal loading device are arranged orthogonally. The vertical loading device is hollow, and there are loading cylinders in the four directions of up, down, front and back. The left and right ends of the horizontal loading device are equipped with pressure transmission columns. Carry out six-sided force loading simulation. The present invention can obtain an unloading rockburst test method in which a rock specimen is suddenly unloaded under force on one side and a loading rockburst test method in which a vertical load is increased after one side is suddenly unloaded, based on a true triaxial, three-directional and six-sided force state.

Description

A true triaxial rock loading and unloading disturbance experiment device and its application method

technical field

The invention relates to a rock mechanics experiment device, in particular to a true triaxial rock loading and unloading disturbance experiment device and a use method thereof.

Background technique

Due to its own weight and the influence of the earth's tectonic movement, the deep rock mass itself is a storage body of stress and energy. Before the disturbance of mining, it is already in a high stress state and stores a large amount of elastic energy. When the rock mass is excavated, the original equilibrium state is broken, causing the redistribution, transfer and release of the initial stress and energy. In actual deep engineering, with the excavation of the working face and roadway, the surrounding coal and rock mass often experience reciprocating loading and unloading. Disturbance is a cyclic disturbance loading and unloading carrier. This process not only leads to changes in rock strength, but also may cause rock bursts during rock loading and unloading, which will bring inestimable economic losses. In view of the characteristics of this mining disturbance engineering, it is urgent to carry out high-level The true triaxial loading and unloading disturbance experiment of rock under stress state can obtain the mechanical strength and deformation characteristics of rock under high stress state, seek the damage evolution and fracture law of deep rock mass, and provide certain theoretical and experimental basis for identifying and predicting the risk of on-site impact .

At present, the true triaxial rock test device has basically realized the program tests of constant test force, constant displacement, constant deformation, constant rate test force, constant rate displacement, constant rate deformation and various control modes and test rates. At the same time, it includes a high-temperature environment module, a creep module, a seepage module and related shear experiments, but there is no loading and unloading disturbance experiment device for deep rock mass. The existing experimental devices have the following deficiencies: 1. It is impossible to realize the unloading rockburst test of sudden unloading on one side; 2. It is impossible to realize the loading rockburst test of increasing the vertical load after sudden unloading on one side; 3. It is impossible to apply intermittently to the rock specimen Shock load perturbation test for one or more shocks.

Contents of the invention

The technical problem to be solved by the present invention is to provide a true triaxial rock loading and unloading disturbance experiment device and its use method, the device can obtain the mechanical strength and deformation characteristics of the rock under the high stress loading and unloading disturbance state.

To achieve the above object, the present invention provides the following technical solutions: a true triaxial rock loading and unloading disturbance experiment device, comprising a vertical loading device (1) and a horizontal loading device (9), the vertical loading device (1) and the horizontal The loading device (9) is distributed orthogonally, and it is characterized in that: the vertical loading device (1) is hollow, and loading oil cylinders are provided in the four directions of up, down, front and rear, and the horizontal loading device (9) There are pressure transmission columns at the left and right ends of the test piece, and the pressure transmission columns are driven by the loading cylinder to realize the six-sided force loading simulation on the test piece.

As a further optimization of the above scheme, the vertical loading device (1) includes an upper beam (16), a lower beam (17), a front column (18), and a rear column (19), and the upper beam (16) is provided with The first loading cylinder (3), the first loading cylinder (3) is used to load vertically downward; the front column (18) is provided with a second loading cylinder (2), and the second loading cylinder carries out Horizontal loading; the rear column (19) is provided with a third loading cylinder (4), and the third loading cylinder is a dynamic loading cylinder for horizontal loading, and the pressure can be reduced to zero in a very short time; the The fourth loading cylinder (7) is provided on the lower beam (17), and the fourth loading cylinder performs vertical loading, and can perform vibration or impact disturbance loading according to different output frequencies.

As a further optimization of the above solution, a disturbance pressure head (13) is provided on the fourth loading cylinder.

As a further optimization of the above solution, a support frame (6) is provided on the inner side of the lower beam (17), and a through hole is provided on the support frame, and the disturbance pressure head passes through the through hole.

As a further optimization of the above scheme, the horizontal loading device (9) includes a left loading frame and a right loading frame (20) arranged at both ends of the connector, and the inner sides of the left loading frame and the right loading frame are equipped with transmission Pressure column (12), the fifth loading oil cylinder is arranged on the said right loading frame.

As a further optimization of the above solution, the bottoms of the left loading frame and the right loading frame are equipped with pulleys that can move along the horizontal guide rails.

As a further optimization of the above scheme, a support base (14) is provided on the guide rail base (10), and the support base (14) and the guide rail base (10) are orthogonally distributed, and the vertical loading device (1) is installed on the support On the bottom platform (14); the horizontal guide rail (15) is supported by the guide rail base (10), and the horizontal loading device (9) moves left and right on the horizontal guide rail (15).

A method for using a true triaxial rock loading and unloading disturbance experiment device, comprising the following steps:

1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading;

2) When a certain load is loaded, the third loading oil cylinder (4) in the horizontal direction is unloaded instantly, and the unloading rockburst experiment is completed.

A method for using a true triaxial rock loading and unloading disturbance experiment device, comprising the following steps:

1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading;

2) When a certain load is loaded, the third loading cylinder (4) in the horizontal direction unloads instantly, and at the same time, the first loading cylinder (3) in the vertical direction increases the vertical load to complete the unloading rockburst experiment.

A method for using a true triaxial rock loading and unloading disturbance experiment device, comprising the following steps:

1), put the rock test piece (5) on the support frame (6), start the first loading oil cylinder (3) in the vertical direction, the second loading oil cylinder (2) in the front and rear direction, and the horizontal loading device (9) in the left and right direction ) of the fifth loading cylinder (8) and its pressure transmission column (12), and select one of the fourth loading cylinder (7) in the vertical direction or the third loading cylinder (4) in the horizontal direction at the same time to complete the three-phase five-sided load;

2) Start the third loading cylinder (4) in the horizontal direction or the fourth loading cylinder (7) in the vertical direction, apply a small amplitude and periodic loading and unloading load as a disturbance load, and record the stress and strain of the whole process at the same time, Obtain the physical state of the rock test piece (5) when it is disturbed at different stress levels, and complete the rock disturbance experiment.

Compared with the prior art, a true triaxial rock loading and unloading disturbance experiment device of the present invention has the following beneficial effects:

(1), a true triaxial rock loading and unloading disturbance experimental device of the present invention has independent loading systems in three mutually perpendicular directions, and the horizontal dynamic loading cylinder in the horizontal direction can be unloaded suddenly, exposing one side of the test piece On the surface, it simulates the phenomenon that the free surface is generated after excavation in underground engineering, and the energy accumulated in the rock body is released to the direction of the free surface to produce a rockburst phenomenon, which provides a necessary means for determining the stress state of the rockburst; Under the force state of three axes, three directions and six sides, the unloading rockburst test method of sudden unloading on one side of the specimen and the loading rockburst test method of increasing vertical load after sudden unloading on one side are obtained.

(2), a kind of true triaxial rock loading and unloading disturbance experiment device of the present invention, can realize the mode of action of different disturbance loads by the disturbance pressure head of different forms: the form of point, the form of surface, the form of point-surface combination act on Rock specimens.

(3) A true triaxial rock loading and unloading disturbance experiment device of the present invention, the horizontal loading device is integrally formed and integrally cast to meet the stiffness requirement parameters of the system. The loading cylinder is installed on the right loading frame of the horizontal loading device, which drives the pressure transmission column on the right loading frame to move to the left, and at the same time gives the right loading frame a reaction force to the right, driving the entire horizontal loading device to move to the right. The pressure transmission column on the left loading frame moves to the right, which ensures that the horizontal loading device simultaneously loads and compresses the horizontal left and right ends of the rock specimen.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a partial enlarged view of place A in Fig. 1;

Fig. 3 is the front view of horizontal loading device of the present invention;

FIG. 4 is a side view of FIG. 3 .

In the figure: 1. Vertical loading device; 2. The second loading cylinder; 3. The first loading cylinder; 4. The third loading cylinder; 5. Rock specimen; 6. Support frame; 7. The fourth loading cylinder; 8. The fifth loading oil cylinder; 9. Horizontal loading device; 10. Guide rail base; 11. Pulley; 12. Pressure transmission column; 13. Disturbance pressure head; 14. Support base; 15. Guide rail; Cross beam; 18, front column; 19, rear column; 20, right loading frame.

detailed description

In order to make the object, technical solution and advantages of the invention clearer, the present invention will be further described in detail below through the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described here are only used to explain the present invention, and are not intended to limit the scope of the present invention.

As shown in Figures 1 to 4, a true triaxial rock loading and unloading disturbance experimental device of the present invention, a true triaxial rock loading and unloading disturbance experimental device, comprises a vertical loading device 1 and a horizontal loading device 9, the vertical loading device 1 and The horizontal loading device is distributed orthogonally, the vertical loading device is hollow, and there are loading oil cylinders in the four directions of up, down, front and rear. The left and right ends of the horizontal loading device are equipped with pressure transmission columns. Driven by the loading cylinder to realize six-sided force loading simulation on the test piece.

In this preferred embodiment, the horizontal guide rail 15 is supported by the guide rail base 10, the guide rail base 10 is provided with a support platform 14, the support platform 14 and the guide rail base 10 are orthogonally distributed, and the guide rail base 10 and the support platform 14 are passed through high-strength bolts Hinged into one body, the vertical loading device 1 is installed on the support base 14, and the horizontal loading device moves left and right on the horizontal guide rail.

The vertical loading device 1 comprises an upper beam 16, a lower beam 17, a front column 18, and a rear column 19. The upper beam 16 is provided with a first loading oil cylinder 3, and the first loading oil cylinder 3 is used to load vertically downward; A second loading cylinder 2 is provided, and the second loading cylinder performs horizontal loading; a third loading cylinder 4 is provided on the rear column 19, and the third loading cylinder is a dynamic loading cylinder, which performs horizontal loading and can realize instant pressure drop to zero; The fourth loading cylinder 7 is provided on the lower crossbeam 17, and the fourth loading cylinder performs vertical loading, and can carry out vibratory disturbance loading according to different output frequencies. In this preferred embodiment, a disturbance pressure head 13 is provided on the fourth loading cylinder, and different forms of disturbance pressure heads can realize different disturbance loads. A support frame 6 is provided on the inner side of the lower beam 17, and the rock test piece 5 is placed on the support frame 6. In addition, a through hole is provided on the support frame, and the disturbance pressure head passes through the through hole to perform a disturbance pressure test on the rock specimen 5 .

The horizontal loading device 9 includes a left loading frame and a right loading frame 20 arranged at both ends of the connector. The inner sides of the left loading frame and the right loading frame are provided with a pressure transmission column 12, and the pressure transmission column is located at the center of the loading frame. The fifth loading oil cylinder is provided on the right loading frame, and the bottoms of the left loading frame and the right loading frame are provided with pulleys 11 that can move along horizontal guide rails 15 . The fifth loading cylinder 8 is installed on the right loading frame of the horizontal loading device, and drives the pressure transmission column on the right loading frame to move to the left, and at the same time gives the right loading frame a reaction force to the right, driving the entire horizontal loading device to move to the right. Movement, the pressure transmission column located on the left loading frame moves to the right, which ensures that the horizontal loading device simultaneously loads and compresses the horizontal left and right ends of the rock specimen.

A true three-axis rock loading and unloading disturbance experiment device of the present invention, the first loading cylinder, the second loading cylinder, the third loading cylinder, and the fourth loading cylinder are located on the same vertical plane, consisting of upper and lower beams and front and rear columns The central position of the frame-like structure constitutes a confining pressure chamber, and the rock specimen is placed in the confining pressure chamber.

In the true triaxial rock loading and unloading disturbance experimental device provided in this preferred embodiment, the parameters of the loading cylinder are as follows:

(1) Technical parameters of the second loading cylinder:

The maximum pressure test force is 3000kN, the effective force measurement range is 30kN-3000kN (1-100% FS), the force measurement resolution is 20N (±1/180000, no classification, the whole process resolution remains the same), the force measurement accuracy ± Within 1%, the force value control fluctuation is less than 0.1%; horizontal loading rate: 10N-50KN/s.

(2) Technical parameters of the first loading cylinder:

Maximum test force: 5000kN; force measurement range 50kN-5000kN (1-100% FS), force measurement resolution 30N (±1/180000, no classification, full resolution unchanged), force measurement accuracy ±1 of the indicated value Within %, the force value control fluctuation is less than 0.1%; vertical loading rate: 10N-50KN/s.

(3) Technical parameters of the third loading cylinder:

The maximum pressure test force is 3000kN, the effective force measurement range is 30kN-3000kN (1-100% FS), the force measurement resolution is 20N (±1/180000, no classification, the whole process resolution remains the same), the force measurement accuracy ± Within 1%, the force value control fluctuation is less than 0.1%; the horizontal loading rate: 10N-50KN/s, the response frequency of the dynamic cylinder is 50Hz; the response speed is 100mm/s.

(4) Technical parameters of the fourth loading cylinder:

(a) Impact disturbance load: the amplitude of the impact force is variable from 0 to 500kN, and it can intermittently apply one or more impacts to the rock specimen.

(b) Vibration disturbance load (random waveform, sine wave, triangle wave, square wave, ramp wave, etc.): the amplitude of vibration load can be changed from 0-500kN. Frequency variable 0-50Hz (amplitude and frequency can be changed in coordination).

The effective force measurement range of disturbance load is 5kN-500kN, and the force measurement accuracy is ±0.5% FS.

Disturbance load requirements: can change the wave form, action point and incident angle, frequency, peak-valley value, amplitude, duration and phase on the rock specimen, and the disturbance load can be applied when the rock specimen is on the stress-strain curve of the whole process. Load anytime.

(c) Mode of action of disturbance loads:

① The form of the point, for example, the disturbance indenter directly acts on a certain designated point of the rock specimen;

② The form of the surface, for example, the disturbance indenter acts directly on a specified surface of the rock specimen, acting on the rock specimen. It can be one form or a combination of both forms.

(5) Technical parameters of the fifth loading cylinder:

The maximum pressure test force is 3000kN, the effective force measurement range is 30kN-3000kN (1-100% FS), the force measurement resolution is 20N (±1/180000, no classification, the whole process resolution remains the same), the force measurement accuracy ± Within 1%, the force value control fluctuation is less than 0.1%; horizontal loading rate: 10N-50KN/s.

Compared with the prior art, a true triaxial rock loading and unloading disturbance experiment device of the present invention,

1) It has independent loading systems in three mutually perpendicular directions, and the horizontal dynamic loading cylinder in the horizontal direction can be unloaded suddenly, exposing one side surface of the specimen, simulating the free surface and rock mass after excavation in underground engineering The phenomenon that the accumulated energy is released to the direction of the air surface to produce rockburst provides a necessary means for determining the stress state of rockburst; under the stress state based on true triaxial, three-direction and six-sided, the single-sided The unloading rockburst test method of sudden unloading of force and the loading rockburst test method of increasing vertical load after sudden unloading of one side, sudden unloading of one side means that the load on a certain side quickly reaches zero, and the other five sides keep the load unchanged;

2) The horizontal loading frame adopts an integral casting structure. The purpose is to meet the rigidity requirements of the system. The loading cylinder is installed in the loading frame at the end of the horizontal loading frame. Pulleys are installed under the loading frame so that the entire horizontal loading frame can Parallel movement on the horizontal guide rail, this structure ensures that both ends of the confining pressure chamber are loaded at the same time when the horizontal load is applied;

3) The action mode of different disturbance loads can be realized through different forms of disturbance indenters: the form of points, the form of surfaces, and the form of combination of points and surfaces act on rock specimens. The point form means that the indenter directly acts on a specified point of the rock specimen, and the surface form means that the indenter directly acts on a specified surface of the rock specimen.

Using a true triaxial rock loading and unloading disturbance experiment device of the present invention can simulate three kinds of experiments, one of which is to perform unloading rockburst experiments, including the following steps:

1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading;

2) When a certain load is loaded, the third loading oil cylinder (4) in the horizontal direction is unloaded instantly, and the unloading rockburst experiment is completed.

Second, the second type of unloading rockburst experiment includes the following steps:

1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading;

2) When a certain load is loaded, the third loading cylinder (4) in the horizontal direction is unloaded instantly, while the first loading cylinder (3) in the vertical direction increases the vertical load to complete the unloading rockburst experiment.

Third, carry out the rock perturbation experiment, including the following steps:

1), put the rock test piece (5) on the support frame (6), start the first loading oil cylinder (3) in the vertical direction, the second loading oil cylinder (2) in the front and rear direction, and the horizontal loading device (9) in the left and right direction ) of the fifth loading cylinder (8) and its pressure transmission column (12), and select one of the fourth loading cylinder (7) in the vertical direction or the third loading cylinder (4) in the horizontal direction at the same time to complete the three-phase five-sided load;

2) Start the third loading cylinder (4) in the horizontal direction or the fourth loading cylinder (7) in the vertical direction, apply a small amplitude and periodic loading and unloading load as a disturbance load, and record the stress and strain of the whole process at the same time, Obtain the physical state of the rock test piece (5) when it is disturbed at different stress levels, and complete the rock disturbance experiment.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (10)

1. A true triaxial rock loading and unloading disturbance experiment device, comprising a vertical loading device (1) and a horizontal loading device (9), the vertical loading device (1) and the horizontal loading device (9) are orthogonally distributed, and its It is characterized in that: the vertical loading device (1) is hollow, and loading oil cylinders are provided in the four directions of up, down, front and rear, and pressure transmission columns are provided at the left and right ends of the horizontal loading device (9), The pressure transmission column is driven by a loading cylinder to simulate six-sided force loading on the rock specimen. 2. A true triaxial rock loading and unloading disturbance experiment device according to claim 1, characterized in that: said vertical loading device (1) comprises an upper beam (16), a lower beam (17), a front column (18 ), rear column (19), described upper beam (16) is provided with first loading oil cylinder (3), and described first loading oil cylinder (3) is used for carrying out vertical downward loading; Described front column (18) A second loading cylinder (2) is provided on the top, and the second loading cylinder performs horizontal loading; a third loading cylinder (4) is provided on the rear column (19), and the third loading cylinder is a dynamic loading cylinder, Horizontal loading can be carried out, and the pressure drop can be reduced to zero in a very short time; the fourth loading oil cylinder (7) is provided on the lower beam (17), and the fourth loading oil cylinder can be used for vertical loading, and can be loaded according to different output frequencies Vibration or shock-type disturbance loading. 3. A true triaxial rock loading and unloading disturbance experiment device according to claim 2, characterized in that a disturbance pressure head (13) is provided on the fourth loading cylinder. 4. A kind of true triaxial rock loading and unloading disturbance experiment device according to claim 2, characterized in that: a support frame (6) is provided on the inner side of the lower beam (17), and a support frame (6) is arranged on the support frame. There is a through hole through which the disturbance head passes. 5. A true triaxial rock loading and unloading disturbance experiment device according to claim 1, characterized in that: the horizontal loading device (9) includes a left loading frame and a right loading frame (20) arranged at both ends of the connector , the inner sides of the left loading frame and the right loading frame are provided with pressure transmission columns (12), and the fifth loading oil cylinder is provided on the right loading frame. 6. A true triaxial rock loading and unloading disturbance experiment device according to claim 1, characterized in that: the bottoms of the left loading frame and the right loading frame are equipped with pulleys that can move along horizontal guide rails. 7. a kind of true three-axis rock loading and unloading disturbance experiment device according to claim 1, is characterized in that: the guide rail base (10) is provided with support base (14), supports base (14) and guide rail base ( 10) Orthogonal distribution, the vertical loading device (1) is installed on the support base (14); the horizontal guide rail (15) is supported by the guide rail base (10), and the horizontal loading device (9) is mounted on the horizontal guide rail (15) Move left and right. 8. A method for using a true triaxial rock loading and unloading disturbance experimental device according to any one of claims 1 to 7, characterized in that: comprising the following steps: 1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading; 2) When a certain load is loaded, the third loading oil cylinder (4) in the horizontal direction is unloaded instantly, and the unloading rockburst experiment is completed. 9. A method for using a true triaxial rock loading and unloading disturbance experimental device according to any one of claims 1 to 7, characterized in that: comprising the following steps: 1), put the rock specimen (5) on the support frame (6), start the first loading cylinder (3) and the fourth loading cylinder (7) in the vertical direction, the second loading cylinder (2) and the The third loading oil cylinder (4), the fifth loading oil cylinder (8) and the pressure transmission column (12) of the horizontal loading device (9) in the left and right directions complete the three-phase six-sided loading; 2) When a certain load is loaded, the third loading cylinder (4) in the horizontal direction unloads instantly, and at the same time, the first loading cylinder (3) in the vertical direction increases the vertical load to complete the unloading rockburst experiment. 10. A method for using a true triaxial rock loading and unloading disturbance experimental device according to any one of claims 1 to 7, characterized in that: comprising the following steps: 1), put the rock test piece (5) on the support frame (6), start the first loading oil cylinder (3) in the vertical direction, the second loading oil cylinder (2) in the front and rear direction, and the horizontal loading device (9) in the left and right direction ) of the fifth loading cylinder (8) and its pressure transmission column (12), and select one of the fourth loading cylinder (7) in the vertical direction or the third loading cylinder (4) in the horizontal direction at the same time to complete the three-phase five-sided load; 2) Start the third loading cylinder (4) in the horizontal direction or the fourth loading cylinder (7) in the vertical direction, apply a small amplitude and periodic loading and unloading load as a disturbance load, and record the stress and strain of the whole process at the same time, Obtain the physical state of the rock test piece (5) when it is disturbed at different stress levels, and complete the rock disturbance experiment.