CN114813402A - A true triaxial impact loading device - Google Patents

Abstract

The invention discloses a true triaxial impact loading device, which relates to the technical field of rock fracturing test equipment. Including a frame, the lower part of the frame is provided with a true three-axis loading device, the upper part is provided with an impact loading device, and the top is mounted with a top plate; the true three-axis loading device includes a base, a loading oil cylinder, a hollow oil cylinder, a transition weight and a second beam. The bottom of the frame, the test piece is placed on the base, and the impact loading device includes a column, a first beam, a telescopic column, an energy storage spring, an energy storage control cylinder, a first electromagnet, a second electromagnet, a heavy hammer and a lift cylinder. The true triaxial impact loading device provided by the present invention, by setting the true triaxial loading device and the impact loading device, respectively applies static load and impact load to the specimen, and realizes the test purpose of dynamic and static synchronous loading on the same coal rock mass. It has the advantages of flexible control and convenient operation.

Description

A true triaxial impact loading device

technical field

The invention relates to the technical field of rock fracturing test equipment, in particular to a true triaxial impact loading device.

Background technique

With the reduction of shallow coal resources and the continuous increase of mining depth, most of the mines have entered a state of deep mining, and some mines have a mining depth of more than 1500m. In deep mining, the rock mass is in a complex mechanical environment of "three highs and one disturbance", and the mine pressure law is significantly different from that in the shallow part. challenge. The frequency and intensity of rock bursts in deep mining are much higher than those in shallow mining, and the resulting casualties and economic losses also present the characteristics of serious and vicious accidents, so people's attention and attention must be paid.

At present, the laboratory mainly conducts tests on dynamic mechanical testing machines, and MTS material mechanical testing machines are usually used in static mechanical experiments. In terms of dynamic load experimental equipment, drop weight, light gas gun and Hopkins pressure rod have been developed successively. However, only a single static load or dynamic load experiment can be carried out above. In reality, the cause of rock burst is mostly due to the combined action of dynamic and static loads, which leads to instability and damage of coal and rock mass. Therefore, it is urgent to research and invent a true triaxial impact loading device to simulate the stress environment characteristics and evolution process when the coal rock dynamic disaster occurs, and provide a basis for the research on the rock burst mechanism.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a true triaxial impact loading device, so as to solve the problem that only a single impact loading device and a true triaxial loading device exist at present.

In order to solve the above-mentioned technical problems, the present invention has adopted the following technical solutions:

A true triaxial impact loading device comprises a frame, the lower part of the frame is provided with a true triaxial loading device, the upper part is provided with an impact loading device, and a top plate is mounted on the top;

The true triaxial loading device includes a base, a loading oil cylinder, a hollow oil cylinder, a transition weight and a second beam, the base is arranged at the bottom of the frame, the test piece is placed on the base, and the loading oil cylinder is arranged on the On the inner wall of the frame, the end is provided with a first indenter and is located around the test piece, the bottom of the hollow cylinder is located above the test piece, the top is set at the bottom of the second beam, and the second beam is set on the inner wall of the frame upper part, the middle part of the second beam is provided with an opening, the transition weight is arranged inside the hollow oil cylinder, the top penetrates the opening of the second beam, and the bottom is provided with a second pressure head;

The impact loading device includes a column, a first beam, a telescopic column, an energy storage spring, an energy storage control cylinder, a first electromagnet, a second electromagnet, a heavy hammer and a lifting cylinder, and the column is arranged on the top plate and the first plate. Between two beams, the first beam is slidably arranged on the upright column, the telescopic column is arranged between the top plate and the first beam, the energy storage spring is sleeved on the telescopic column, the The energy storage control cylinder is arranged at the bottom of the top plate, the first electromagnet is arranged at the bottom of the energy storage control cylinder, and the second electromagnet is arranged at the top of the first beam and corresponds to the first electromagnet The weight is arranged at the bottom of the first beam, the end is provided with a third pressure head, and the lifting cylinder is arranged at the top of the second beam.

Further, it also includes a monitoring system, the monitoring system includes a load sensor, a displacement sensor and a load-displacement integrated sensor, the load sensor is arranged between the weight and the third indenter, and the displacement sensor is arranged on the first Between a beam and the second electromagnet, the load-displacement integrated sensor is arranged between the loading oil cylinder and the first pressure head, and between the transition weight and the second pressure head.

Further, the number of the upright column, the energy storage control oil cylinder and the lift oil cylinder is two, the energy storage control oil cylinder and the lift oil cylinder are located inside the two upright columns, and the telescopic column is located in the middle of the inner side of the two energy storage control oil cylinders, The heavy hammer is located at the inner middle position of the two lifting oil cylinders.

Further, a damping spring is sleeved at the lower part of the upright column, a protective pad is provided on the top of the damping spring, and the bottom is in contact with the second beam.

Further, the distance between the upper end surface of the protective pad and the second beam is greater than the maximum impact displacement of the first beam.

Further, it also includes a control system, wherein the monitoring system, the energy storage control cylinder, the loading cylinder, the first electromagnet, the second electromagnet and the lift cylinder are all connected to the control system.

A test method for a true triaxial impact loading device, comprising the following steps:

S1. Determine the compression deformation of the energy storage spring according to the stiffness coefficient of the energy storage spring and the design elastic energy value, and determine the stroke of the energy storage control cylinder and the lifting cylinder by the compression deformation.

S2. Turn on the lifting oil cylinder to raise the height of the first beam, compress the energy storage spring to deform it to obtain elastic deformation energy, and connect the first electromagnet and the second electromagnet, so that the second electromagnet on the first beam is connected to the bottom of the top plate. The first electromagnet is connected to fix the first beam, the compression deformation of the energy storage spring is obtained through the displacement sensor, and then the lifting cylinder is restored to the initial position,

S3. Place the specimen, place the specimen on the base, and apply a horizontal static load to the specimen through four loading cylinders. The integrated load-displacement sensor records the data of monitoring displacement and load, and controls the transition weight pair through the hollow cylinder. A static load is applied to the upper surface of the specimen,

S4. After the loading cylinder loads the specimen to the set load, power off the first electromagnet and the second electromagnet. At this time, the first beam will move downward, and the first beam will drive the weight to apply the transition weight to the transition weight. Impact, the transition weight exerts an impact on the specimen, and the specimen is damaged by the impact,

S5. The loading cylinder stops loading, the specimen is decompressed, the monitored data is stored, and the magnitude of the static load and impact load and the damage process of the specimen are obtained by processing the collected data.

Compared with the prior art, the present invention has the following beneficial effects:

By setting the true triaxial loading device and the impact loading device, the static load and impact load are applied to the specimen respectively, and the static load and dynamic load experiments are completed at the same time. The advantages of control and easy operation can better simulate the stress environment characteristics and evolution process when coal-rock dynamic disasters occur, thus providing a basis for the study of rock burst mechanism.

Description of drawings

Figure 1 is a schematic structural diagram of the present invention.

2 is a horizontal cross-sectional view of the true triaxial loading device of the present invention.

Among them, 1-energy storage spring, 2-energy storage control cylinder, 3-first electromagnet, 4-weight hammer, 5-third pressure head, 6-load sensor, 7-lifting cylinder, 8-transition weight, 9-Test piece, 10-Base, 11-Telescopic column, 12-Frame, 13-Column, 14-Displacement sensor, 15-First beam, 16-Protective pad, 17-Shock spring, 18-Second beam, 19-Hollow cylinder, 20-Load displacement integrated sensor, 21-Load cylinder, 22-Second pressure head.

Detailed ways

The technical solutions of the present invention will be further described below through the accompanying drawings and embodiments.

Example 1

1 to 2, the present invention provides a true triaxial impact loading device, including a frame 12, the lower part of the frame 12 is provided with a true triaxial loading device, the upper part is provided with an impact loading device, and a top plate is mounted on the top;

The true triaxial loading device includes a base 10 , a loading cylinder 21 , a hollow cylinder 19 , a transition weight 8 and a second beam 18 , the base 10 is arranged at the bottom of the frame 12 , and the test piece 9 is placed on the base 10 Above, the loading oil cylinder 21 is arranged on the inner wall of the frame 12, the end is provided with a first indenter and is located around the test piece 9, the bottom of the hollow oil cylinder 19 is located above the test piece 9, and the top is arranged on the second The bottom of the beam 18, the second beam 18 is arranged on the inner wall of the frame 12, the middle part of the second beam 18 is provided with an opening, the transition weight 8 is arranged inside the hollow cylinder, and the top penetrates the second beam 18 In this embodiment, the number of loading cylinders 21 is four, the four surfaces in the horizontal direction of the test piece 9 are statically loaded by the loading cylinder 21, and the top surface of the test piece 9 is made of hollow The oil cylinder 19 controls the transition weight 8 to apply static load. The true triaxial loading device can simulate the real stress state of rocks stored in the ground. Because the actual engineering rock has a complex stress state underground, and there is a big difference between the three principal stresses, the true triaxial loading device can better restore the real stress state of the underground coal and rock, and can realize Applying principal stress and impact disturbance in different directions to coal and rock is helpful to better study the force failure law of coal and rock in the real geographical environment.

The impact loading device includes a column 13, a first beam 15, a telescopic column 11, an energy storage spring 1, an energy storage control cylinder 2, a first electromagnet 3, a second electromagnet, a weight 4 and a lifting cylinder 7. The column 13 is arranged between the top plate and the second beam 18 , the first beam 15 is slidably arranged on the column 13 , the telescopic column 11 is arranged between the top plate and the first beam 15 , the The energy storage spring 1 is sleeved on the telescopic column 11 , the energy storage control cylinder 2 is arranged at the bottom of the top plate, the first electromagnet 3 is arranged at the bottom of the energy storage control cylinder 2 , the second The electromagnet is arranged on the top of the first beam 15 and corresponding to the first electromagnet 3 , the weight 4 is arranged at the bottom of the first beam 15 , and the end is provided with a third pressure head 5 . The lift cylinder 7 is arranged on the top of the second beam 18 . In this embodiment, the impact loading device can apply a dynamic load to the specimen 9. When in use, the lifting cylinder 7 is lifted to make the first beam 15 move upward, compressing the energy storage spring 1 on the telescopic column 11 until the first beam The second electromagnet on the 15 is connected with the first electromagnet 3 at the bottom of the energy storage control cylinder 2, so that the first beam 15 is fixedly connected to the top plate, and then the lifting cylinder 7 is retracted and lowered to the initial position; When the dynamic load is applied to the specimen 9, the second electromagnet and the first electromagnet 3 are powered off, so that the first beam 15 is disconnected from the top plate. At this time, the first beam 15 will move downward rapidly, and the first beam 15 The top weight 4 will impact the transition weight 8, so that the transition weight 8 will impact the specimen to complete the application of the dynamic load.

The coal rock in the mine is not only subjected to the pressure of the upper roof, but also to different degrees of disturbance such as roof fracture and artificial blasting. It is necessary to study the failure characteristics of coal and rock under combined dynamic and static loading. An impact loading device was designed, and on the basis of static load loading, impact disturbance was applied to coal and rock, and the failure characteristics of coal and rock under combined loading were explored by using the test method, which provided data support for the prevention and control of rock burst.

Preferably, it also includes a monitoring system and a control system, the monitoring system includes a load sensor 6 , a displacement sensor 14 and a load-displacement integrated sensor 20 , the load sensor 6 is arranged between the weight 4 and the third indenter 5 . time, used to measure the dynamic load applied by the weight 4; the displacement sensor 14 is arranged between the first beam 15 and the second electromagnet to measure the compression deformation of the energy storage spring 1; the load and displacement are integrated The sensor 20 is arranged between the loading cylinder 21 and the first pressure head, and between the transition weight 8 and the second pressure head 22, and is used to measure the load and displacement. In this embodiment, the monitoring system, the energy storage control cylinder 2, the loading cylinder 21, the first electromagnet, the second electromagnet and the lifting cylinder 7 are all connected to the control system, and the control system is a controller, which is responsible for the monitoring system. The transmitted data is stored and processed, and the opening and closing control of the energy storage control cylinder 2, the loading cylinder 21, the first electromagnet, the second electromagnet and the lifting cylinder 7 is performed.

Preferably, the number of the column 13 , the energy storage control cylinder 2 and the lift cylinder 7 is two, the energy storage control cylinder 2 and the lift cylinder 7 are located inside the two columns 13 , and the telescopic column 11 is located at the two storage tanks. The inner middle position of the oil cylinder 2 can be controlled, and the weight 4 is located at the inner middle position of the two lifting oil cylinders 7 .

Preferably, a damping spring 17 is sleeved on the lower part of the upright column 13 , a protective pad 16 is provided on the top of the damping spring 17 , and the bottom is in contact with the second beam 18 . The shock-absorbing spring 17 can buffer and reduce the weight of the first beam 15 that suddenly descends, and the protective pad 16 can protect the shock-absorbing spring 17 .

Preferably, the distance between the upper end surface of the protective pad 16 and the second beam 18 is greater than the maximum impact displacement of the first beam 15 .

Example 2

A test method for a true triaxial impact loading device, comprising the following steps:

S1. Determine the compression deformation of the energy storage spring 1 according to the stiffness coefficient and the design elastic energy value of the energy storage spring 1, and determine the stroke of the energy storage control cylinder 2 and the lifting cylinder 7 by the compression deformation.

S2, open the lift cylinder 7 to raise the height of the first beam 15, compress the energy storage spring 1 to deform it to obtain elastic deformation energy, and connect the first electromagnet and the second electromagnet, so that the second electromagnet on the first beam 15 It is connected with the first electromagnet at the bottom of the top plate, thereby fixing the first beam 15, obtaining the compression deformation of the energy storage spring 1 through the displacement sensor 14, and then restoring the lifting cylinder 7 to the initial position,

S3. Place the test piece, place the test piece on the base 10, apply a horizontal static load to the test piece through the four loading cylinders 21, and record the data of the monitoring displacement and the load by the integrated load-displacement sensor 20, and control the control through the hollow cylinder 19. The transition weight 8 applies a static load to the upper surface of the specimen,

S4. After the loading cylinder 21 loads the specimen to the set load, the first electromagnet and the second electromagnet are powered off. At this time, the first beam 15 will move downward, and the first beam 15 will drive 4 pairs of heavy hammers. The transition weight 8 applies an impact, and the transition weight 8 applies an impact to the test piece, and the test piece is damaged by the impact.

S5. The loading cylinder 21 stops loading, the test piece is decompressed, the monitored data is stored, and the magnitude of the static load and impact load and the damage process of the test piece are obtained by processing the collected data.

The above are only preferred embodiments of the present invention, and do not limit the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are still within the scope of the present invention. within the scope of the technical solution of the present invention.

Claims (7)

1. A true triaxial impact loading device is characterized by comprising a frame, wherein the lower part of the frame is provided with the true triaxial loading device, the upper part of the frame is provided with the impact loading device, and the top of the frame is provided with a top plate;

the true triaxial loading device comprises a base, a loading oil cylinder, a hollow oil cylinder, a transition heavy hammer and a second cross beam, wherein the base is arranged at the bottom of the frame, a test piece is placed on the base, the loading oil cylinder is arranged on the inner wall of the frame, a first pressure head is arranged at the end part of the loading oil cylinder and positioned around the test piece, the bottom of the hollow oil cylinder is positioned above the test piece, the top of the hollow oil cylinder is arranged at the bottom of the second cross beam, the second cross beam is arranged on the inner wall of the frame, an opening is formed in the middle part of the second cross beam, the transition heavy hammer is arranged in the hollow oil cylinder, the top of the transition heavy hammer penetrates through the opening of the second cross beam, and the bottom of the transition heavy hammer is provided with a second pressure head;

impact loading device includes stand, first crossbeam, flexible post, energy storage spring, energy storage control hydro-cylinder, first electromagnet, second electromagnet, weight and lift cylinder, the stand set up in between roof and the second crossbeam, first crossbeam slide set up in on the stand, flexible post set up in between roof and the first crossbeam, the energy storage spring housing is located on the flexible post, the energy storage control hydro-cylinder set up in the roof bottom, first electromagnet set up in energy storage control hydro-cylinder bottom, the second electromagnet set up in first crossbeam top and with first electromagnet corresponds the setting, the weight set up in first crossbeam bottom, the tip is equipped with the third pressure head, lift cylinder set up in second crossbeam top.

2. The true triaxial impact loading device according to claim 1, further comprising a monitoring system, wherein the monitoring system comprises a load sensor, a displacement sensor and a load-displacement integrated sensor, the load sensor is disposed between the weight and the third ram, the displacement sensor is disposed between the first beam and the second electromagnet, and the load-displacement integrated sensor is disposed between the loading cylinder and the first ram and between the transition weight and the second ram.

3. The true triaxial impact loading device according to claim 1, wherein the number of the vertical columns, the energy storage control cylinder and the lift cylinder is two, the energy storage control cylinder and the lift cylinder are located inside the two vertical columns, the telescopic column is located at a middle position inside the two energy storage control cylinders, and the weight is located at a middle position inside the two lift cylinders.

4. The true triaxial impact loading device according to claim 1, wherein a damping spring is sleeved on a lower portion of the upright, a protection pad is arranged on a top portion of the damping spring, and a bottom portion of the damping spring is in contact with the second beam.

5. A true triaxial impact loading device according to claim 4, wherein the distance between the upper end face of the protection pad and the second beam is greater than the maximum impact displacement of the first beam.

6. The true triaxial impact loading device according to claim 2, further comprising a control system, wherein the monitoring system, the energy storage control cylinder, the loading cylinder, the first electromagnet, the second electromagnet and the lift cylinder are all connected to the control system.

7. A test method of a true triaxial impact loading device is characterized by comprising the following steps:

s1, determining the compression deformation of the energy storage spring according to the stiffness coefficient and the designed elastic energy value of the energy storage spring, determining the strokes of the energy storage control oil cylinder and the lifting oil cylinder according to the compression deformation,

s2, starting the lifting oil cylinder to lift the height of the first cross beam, compressing the energy storage spring to deform to obtain elastic deformation energy, connecting the first electromagnet and the second electromagnet to connect the second electromagnet on the first cross beam with the first electromagnet at the bottom of the top plate so as to fix the first cross beam, obtaining the compression deformation of the energy storage spring through the displacement sensor, then restoring the lifting oil cylinder to the initial position,

s3, placing a test piece, placing the test piece on a base, applying static load to the test piece in the horizontal direction through four loading oil cylinders, recording data of monitoring displacement and load by a load-displacement integrated sensor, controlling a transition heavy hammer to apply the static load to the upper surface of the test piece through a hollow oil cylinder,

s4, after the loading oil cylinder loads the test piece to the set load, the first electromagnet and the second electromagnet are powered off, at the moment, the first beam moves downwards, the first beam drives the heavy hammer to impact the transition heavy hammer, the transition heavy hammer impacts the test piece, and the test piece is damaged by the impact,

and S5, stopping loading by the loading oil cylinder, relieving pressure of the test piece, storing the monitored data, and processing the collected data to obtain the size of the static load and the impact load of the test piece and the process of damage.

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