A blasting vibration simulation impact device for shear rheology test

Abstract

The present invention relates to a blasting vibration simulation impact device for shear rheology test, including an impact load generating mechanism, a transmission mechanism, a strain recording mechanism and a receiving mechanism. The impact load generating mechanism is provided with an angle dial, a pointer, a steel frame, a coil, a current controller and a pendulum; the transmission mechanism is provided with an incident rod, a sleeve and a combination plate; the strain recording mechanism is provided with a resistance strain gauge connected by a wire, an ultra-dynamic strain gauge and a data acquisition instrument; the receiving mechanism is provided with an upper shear box, a lower shear box, a normal static load electric cylinder and a horizontal static load electric cylinder. The device has a simple structure and is easy to operate. The pendulum can be controlled by a current controller to generate an impact load, or the pendulum can be manually lifted to generate an impact load, so that the impact load is generated simply and safely. The impact load is applied to the upper shear box, and the transient stress and high-frequency strain of the sample under the impact load are recorded, which can more realistically simulate the actual working conditions, making the impact of the simulated blasting vibration more realistic and reasonable.

Description

Technical Field

[0001] The invention relates to a blasting vibration simulation impact device for shear rheology test. Background Art

[0002] Weak interlayers are widely found in limestone mines in southwest my country. Due to their low mechanical strength, poor hydraulic properties, and obvious rheological effects, soft interlayers often become the weak link in the stability of high slopes in these limestone mines. In the long-term large-scale mining process, the blasting vibration generated by step blasting will affect the rheological properties of the soft interlayers, becoming a key factor leading to the instability of high slopes in mines. In order to simulate how the rheological properties of the soft interlayers of the high slopes change under the repeated action of blasting vibration, the most direct and effective method is to use indoor shear rheological tests under impact loads to obtain the mechanical property parameters of the soft interlayers.

[0003] At present, the application of impact loads generally has the following problems:

[0004] ① In existing indoor tests, the Hopkinson bar test technology is mainly used to perform dynamic impact tests on rocks. The Hopkinson bar has a complex structure and occupies a large area, which is not suitable for small laboratories; if the operation is not careful, the deviation of the bullet launch path will cause huge safety hazards;

[0005] ② In the traditional impact load application process, the pendulum is usually lifted manually, and the impact of the pendulum cannot be automatically controlled;

[0006] ③. There is a problem with the application location of the impact load: The application location of the traditional impact load is set at the lower shear box. When the incident rod hits the lower shear box, the transmitted impact load will impact the static pressure electric cylinder used for servo on the right side of the lower shear box. Under long-term repeated impacts, the ball structure inside the horizontal static load electric cylinder may be slightly misaligned, affecting the servo accuracy and reducing the service life of the horizontal static load electric cylinder;

[0007] ④. In the traditional impact load application process, there is a lack of recording equipment for the impact load, and it is impossible to record the transient pressure and high-frequency strain under the impact load. Summary of the invention

[0008] The purpose of the present invention is to solve the problems existing in the prior art, overcome the above-mentioned defects and provide a blasting vibration simulation impact device for shear rheology test. The device innovates the way of applying impact load, designs an automatically controlled pendulum hammer, occupies a small area, is safer and saves space compared to the Hopkinson pressure bar; at the same time, it changes the traditional application position of the impact load, adopts the method of applying the impact load on the upper shear box, thereby protecting the servo hydrostatic electric cylinder on the right side of the lower shear box; a recording mechanism is also set up to facilitate deeper scientific research.

[0009] To achieve the above object, the technical solution adopted by the present invention is: to provide a blasting vibration simulation impact device for shear rheology test, which is equipped with an impact load generating mechanism, a transmission mechanism, a strain recording mechanism and a receiving mechanism;

[0010] The impact load generating mechanism is an impact load generating mechanism, which is provided with a pendulum, a steel frame, a current controller, a coil, a wire, a pointer and an angle dial; the pendulum is suspended from the top of the steel frame, the current controller is connected to the coil through a wire, the current controller causes the coil to generate a magnetic field of a set strength according to the input current value, and controls the pendulum to swing through magnetic force; an angle dial is fixed on the steel frame, the angle dial is installed in front of the pendulum, the pointer is installed on the upper part of the pendulum and extends in front of the angle dial through a right angle of 90 degrees, and the pointer indicates the swing angle scale when the pendulum swings;

[0011] The transmission mechanism is an impact load transmission mechanism, which is provided with a sleeve, an incident rod and a combined plate; the sleeve is welded on the steel frame, the incident rod is placed in the sleeve, the outer diameter of the incident rod is smaller than the inner diameter of the sleeve, one end of the incident rod is in contact with the pendulum in a static state, and the other end of the incident rod is in contact with and aligned with the force transmission plate in the combined plate; the combined plate is composed of a pressure rod, a fixed plate, a force transmission plate, a pin and a screw, the force transmission plate is fastened to the fixed plate by a pin, the fixed plate is fixed to the left side of the frame by a screw, a pressure rod is welded on the right side of the force transmission plate, and the pressure rod is aligned with the center of the left side of the upper shear box and fits tightly;

[0012] The strain recording mechanism is provided with a resistance strain gauge, an ultra-dynamic strain gauge and a data acquisition instrument connected by wires; a plurality of resistance strain gauges are pasted on the sample, the resistance strain gauge is connected to the ultra-dynamic strain gauge by wires, and the ultra-dynamic strain gauge is connected to the data acquisition instrument by wires;

[0013] The receiving mechanism is an impact load receiving mechanism, which is provided with an upper shear box, a lower shear box, two baffles with holes, a pressure plate, a normal static load electric cylinder and a horizontal static load electric cylinder; the upper shear box and the lower shear box form a complete shear box; the holes of the two baffles with holes are embedded with balls, wherein the first baffle with holes is fixed to the frame partition by screws, and the lower shear box is placed on the first baffle with holes; the upper shear box is installed on the lower shear box, and the sample is installed in the shear box; the upper shear box is provided with a rectangular hole, which provides a wire lead-out channel for the resistance strain gauge pasted on the sample; the second baffle with holes is also fixed to the upper shear box by screws; the pressure plate is placed on the second baffle with holes, the edge of the pressure plate is aligned with the shear box, and the normal static load electric cylinder is pressed on the pressure plate to apply normal static load pressure to the sample; the horizontal static load electric cylinder is installed on the right side of the lower shear box to apply horizontal static load pressure to the sample.

[0014] The combined plate is used to transfer the impact load to the shear box when the transfer mechanism transfers the impact load, and is used to fix the upper shear box when the impact load is not transferred.

[0015] The incident rod, the combined plate and the shear box are made of the same material, stainless steel, to ensure that the propagation speed of the vibration wave remains unchanged during the transmission process.

[0016] Compared with the prior art, the blasting vibration simulation impact device of the present invention has the following advantages:

[0017] ⑴. The blasting vibration simulation impact device of the present invention generates impact loads through an impact load generating mechanism. The current controller in the present invention is connected to the coil through a wire. The current controller can input different current values ​​to make the coil generate a magnetic field of a set strength, and control the swing of the pendulum through magnetic force; at the same time, the pendulum can also be manually lifted to apply impact loads according to the angle corresponding to the pointer when the pendulum rotates. The combination of automatic and manual operation improves the risk resistance of the test system.

[0018] (2) The device of the present invention can realize the application of impact load to the upper shear box through the provided combination plate. The device sets the application of impact load on the upper shear box, which changes the traditional application of impact load on the lower shear box, avoids the indirect impact on the horizontal static load electric cylinder on the right side of the lower shear box due to the application of impact load on the lower shear box during the test, and can effectively protect the horizontal static load electric cylinder, which helps to maintain the test accuracy and extend the service life of the horizontal static load electric cylinder. At the same time, when the transmission mechanism transmits the impact load, the combination plate plays the role of transmitting the impact load; when the impact load is not transmitted, the combination plate replaces the traditional fixed rod on the left side of the upper shear box, realizing "one plate for two uses".

[0019] ⑶. The device of the present invention is provided with a rectangular hole in the upper shear box, so that the rectangular hole can provide a wire lead-out channel for the resistance strain gauge pasted on the sample.

[0020] (⑷) In the present invention, a perforated baffle plate with embedded balls is arranged between the pressure plate and the upper shear box, and between the lower shear box and the frame partition, so that the sliding friction between the pressure plate and the upper shear box, and between the lower shear box and the frame partition is changed into rolling friction, thereby reducing the friction of the device.

[0021] ⑸. The device of the present invention has a simple structure and is easy to operate. The device can generate an impact load by controlling the pendulum through a current controller or manually lifting the pendulum, making the generation of the impact load simple and safe. The transmission mechanism can transmit the impact load to the upper shear box, and the strain change of the sample under the impact load is recorded by the ultra-dynamic strain gauge and the data acquisition instrument, and the transient pressure and high-frequency strain of the sample under the impact load are obtained, providing data support for further scientific research. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a front view structural schematic diagram of the blasting vibration simulation impact device of the present invention.

[0023] Figure 2 It is a side view structural schematic diagram of the relative positions of the steel frame, pendulum, angle dial and pointer in the present invention.

[0024] Figure 3 It is a front view structural schematic diagram of the combined board in the present invention.

[0025] Figure 4 for Figure 3 Schematic diagram of the side view structure of the combined plate in.

[0026] Figure 5 for Figure 3 Schematic diagram of the structure of the combined plate from top view.

[0027] Figure 6 It is a schematic diagram of the structure in which the sample of the present invention is installed in the shear box.

[0028] Figure 7 It is a schematic diagram of the front view and top view of the baffle with holes embedded with balls in the present invention.

[0029] In the above figure: 1—rectangular hole; 2—pressure plate; 3—normal static load electric cylinder; 4—frame; 5—pressure rod; 6—pin; 7—fixed plate; 8—force transmission plate; 9—incident rod; 10—sleeve; 11—angle dial; 12—steel frame; 13—wire; 14—pointer; 15—current controller; 16—pendulum; 17—baffle with holes; 18—ball; 19—resistance strain gauge; 20—sample; 21—lower shear box; 22—upper shear box; 23—frame partition; 24—horizontal static load electric cylinder; 25—data acquisition instrument; 26—ultra-dynamic strain gauge; 27—screw; 28—coil. DETAILED DESCRIPTION

[0030] The blasting vibration simulation impact device for shear rheology test of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the front, back, left, and right described in the present invention are only for the convenience of description according to the illustrated structure. The embodiments of the present invention provide detailed implementation methods and specific operating processes, but the implementation of the present invention is not limited to the following embodiments.

[0031] Embodiment 1: The present invention provides a blasting vibration simulation impact device for shear rheology test, the structure of which is as follows: Figure 1 As shown, it includes an impact load generating mechanism, a transmission mechanism, a strain recording mechanism and a receiving mechanism.

[0032] The impact load generating mechanism is an impact load generating mechanism, which is provided with a pendulum 16, a steel frame 12, a current controller 15, a wire 13, a coil 28, a pointer 14 and an angle dial 11; the pendulum is suspended from the top of the steel frame, and the current controller is connected to the coil through a wire. The current controller causes the coil to generate magnetic fields of different strengths according to different input current values, and controls the pendulum to swing through magnetic force; see Figure 2 An angle dial is fixed on the steel frame, the angle dial is installed in front of the pendulum, the pointer is installed on the upper part of the pendulum and extends to the front of the angle dial through a 90-degree right angle, so that when the pendulum swings, the pointer can indicate the swing angle scale in front of the angle dial.

[0033] The transmission mechanism is an impact load transmission mechanism, which is provided with a sleeve 10, an incident rod 9 and a combined plate. The sleeve is welded on a steel frame 12, and the incident rod is placed in the sleeve. The outer diameter of the incident rod is smaller than the inner diameter of the sleeve. The incident rod can move left and right in the sleeve. One end of the incident rod contacts the pendulum in a static state, and the other end of the incident rod contacts and aligns with the force transmission plate 8 in the combined plate, so that the incident rod 9 can accurately hit the force transmission plate 8 when hit by the pendulum. Figure 1 , 3, 4, 5, the combined plate is composed of a pressure rod 5, a fixed plate 7, a force transmission plate 8, a pin 6 and a screw 27. The force transmission plate is fastened to the fixed plate by a pin, and the fixed plate is fixed to the left side of the frame 4 by a screw 27. A pressure rod is welded on the right side of the force transmission plate, and the pressure rod is aligned with the center of the left side of the upper shear box 22 and fits tightly.

[0034] The strain recording mechanism is provided with a resistance strain gauge 19, an ultra-dynamic strain gauge 26 and a data acquisition device 25 connected by a wire 13; see Figure 1 , 6 The resistance strain gauges are multiple pieces pasted on the sample 20, the resistance strain gauges are connected to the ultra-dynamic strain gauge 26 through wires, and the ultra-dynamic strain gauge is connected to the data acquisition instrument through wires.

[0035] See also Figure 1 and Figure 7 The receiving mechanism is an impact load receiving mechanism, which is provided with an upper shear box 22, a lower shear box 21, two perforated baffles 17, a pressure plate 2, a normal static load electric cylinder 3 and a horizontal static load electric cylinder 24. The upper shear box and the lower shear box form a complete shear box; the two perforated baffles 17 are both embedded with ball bearings 18, wherein the first perforated baffle is fixed to the frame partition 23 by screws 27, and the lower shear box is placed on the first perforated baffle; the upper shear box is installed on the lower shear box, and the sample 20 is installed in the shear box; the upper shear box is provided with a rectangular hole 1, and the rectangular hole provides a wire lead-out channel for the resistance strain gauge 19 pasted on the sample; a second perforated baffle 17 is installed above the upper shear box, and the second perforated baffle is also fixed to the upper shear box by screws; the pressure plate 2 is placed on the second perforated baffle, and the edge of the pressure plate is aligned with the edge of the shear box, and the normal static load electric cylinder 3 is pressed on the pressure plate to apply normal static load pressure to the sample; the horizontal static load electric cylinder 24 is installed on the right side of the lower shear box to apply horizontal static load pressure to the sample.

[0036] The pendulum in the device can be made of magnetic steel or stainless steel other than austenite structure. The incident rod, combined plate and shear box are made of the same material, that is, the same stainless steel material, so that the propagation speed of the vibration wave during the transmission process can be guaranteed to remain unchanged.

[0037] When the incident rod 9 is hit by the pendulum 16, the incident rod transmits the impact load to the upper shear box 22 through the force transmission plate 8 and the pressure rod 5, and finally transmits the impact load to the sample 20. When the vibration wave is transmitted to the sample, the resistance strain gauge 19 pasted on the sample is deformed due to the force, which causes the resistance of the resistance strain gauge to change. The ultra-dynamic strain gauge 26 can collect the change of the electrical signal and record the test data of the strain change under the impact load through the data acquisition instrument 25, so as to make further analysis as needed.

[0038] The specific steps of using the above-mentioned blasting vibration simulation impact device to conduct a shear rheology test are as follows:

[0039] ⑴. The shape of sample 20 is a rectangular parallelepiped with a length of 150 mm in the shear direction and 75 mm in the other two directions. The sample is made of carbonaceous shale and other samples with lower strength.

[0040] ⑵、Preparation: The sleeve 10 is pre-welded on the steel frame 12, and the pressure rod 5 is pre-welded on the force transmission plate 8; the angle dial 11 and the pendulum 16 are installed on the steel frame, and the pointer 14 is installed on the upper end of the pendulum 16. One end of the pointer has a 90-degree right angle. After installation, the pointer extends in front of the angle dial; the multiple resistance strain gauges 19 connected with the wires 13 are respectively pasted on the sample 20. Check whether the current controller 15, the ultra-dynamic strain gauge 26 and the data acquisition instrument 25 can be turned on and used normally. After the inspection is completed, turn off the machine and wait for installation.

[0041] ⑶. Installation work: Connect the current controller 15 to the coil 28 with the wire 13; fasten the fixing plate 7 to the preset position on the left side of the frame 4 with four round screws 27, and tighten the force transmission plate 8 to the fixing plate through the pin 6; place the incident rod 9 in the sleeve 10, the outer diameter of the incident rod is smaller than the inner diameter of the sleeve, and the incident rod can move left and right in the sleeve. Apply appropriate force during installation to ensure that the incident rod, the pendulum and the force transmission plate 8 are aligned and in contact when the pendulum 16 is stationary; fix the first perforated baffle 17 embedded with the ball 18 to the frame partition 23 through the round screws 27; place the lower shear box 21 on the first perforated baffle, and then place the sample 20 with the wire 13 and the resistance strain gauge 19 in the lower shear box, pass the wire through the rectangular hole 1 on the upper shear box 22, and then slowly install the upper shear box. It should be noted that when installing the lower shear box and the upper shear box, When cutting the box, the verticality and parallelism of the upper and lower shear boxes should be ensured. When installing this part, avoid touching the resistance strain gauge to avoid deformation of the resistance strain gauge and affect the test results. Then take the second perforated baffle 17 embedded with the ball 18 and fasten it to the upper shear box 22 through a circular screw, place the pressure plate 2 on the second perforated baffle, and align the edge of the pressure plate with the edge of the upper shear box. Connect the wire connected with the resistance strain gauge to the ultra-dynamic strain gauge 26, and use the wire to connect the ultra-dynamic strain gauge and the data acquisition instrument 25. During the installation process, it is also necessary to pay attention to whether the contact surfaces of the pendulum, the incident rod, the force transmission plate, the pressure rod and the shear box are processed very flat and the components are in full contact.

[0042] (4) Review work: Check again whether the pendulum 16 is in contact and alignment with the incident rod 9 when stationary, whether the incident rod is in contact and aligned with the force transmission plate 8, whether the pressure rod 5 is aligned with the center line of the left contact surface of the upper shear box 22 and fits tightly, whether the current controller 15, the ultra-dynamic strain gauge 26 and the data acquisition instrument 25 are installed in the test position, and whether the wire connection is normal.

[0043] ⑸. Start the test after review: adjust the pressure values ​​of the normal static load electric cylinder 3 and the horizontal static load pressure cylinder 24 to the designed values ​​of the test plan; turn on the current controller 15, the ultra-dynamic strain gauge 26 and the data acquisition instrument 25, and use the current controller to control the pendulum to generate the impact load for the test according to the parameters and time of applying the impact load designed in the test plan, and use the data acquisition instrument to record the test data of the strain change under the impact load, and make further analysis as needed.

[0044] The device of the present invention has a simple structure, is easy to operate, is safe to use, and can simulate actual working conditions more realistically, making the impact of simulated blasting vibration more realistic and reasonable. The present invention generates an impact load by controlling a pendulum through a current controller or manually lifting the pendulum, and applies an impact load to an upper shear box, records the strain change of the sample under the impact load through an ultra-dynamic strain gauge and a data acquisition instrument, and obtains the transient pressure and high-frequency strain of the sample under the impact load, providing more accurate data support for further scientific research.

Claims

1. A blasting vibration simulation impact device for shear rheology test, comprising an impact load generating mechanism, a transmission mechanism, a strain recording mechanism and a receiving mechanism; characterized in that: The impact load generating mechanism is an impact load generating mechanism, which is provided with a pendulum, a steel frame, a current controller, a coil, a wire, a pointer and an angle dial; the pendulum is suspended from the top of the steel frame, the current controller is connected to the coil through a wire, the current controller causes the coil to generate a magnetic field of a set strength according to the input current value, and controls the pendulum to swing through magnetic force; an angle dial is fixed on the steel frame, the angle dial is installed in front of the pendulum, the pointer is installed on the upper part of the pendulum and extends in front of the angle dial through a right angle of 90 degrees, and the pointer indicates the swing angle scale when the pendulum swings; The transmission mechanism is an impact load transmission mechanism, which is provided with a sleeve, an incident rod and a combined plate; the sleeve is welded on the steel frame, the incident rod is placed in the sleeve, the outer diameter of the incident rod is smaller than the inner diameter of the sleeve, one end of the incident rod is in contact with the pendulum in a static state, and the other end of the incident rod is in contact with and aligned with the force transmission plate in the combined plate; the combined plate is composed of a pressure rod, a fixed plate, a force transmission plate, a pin and a screw, the force transmission plate is fastened to the fixed plate by a pin, the fixed plate is fixed to the left side of the frame by a screw, a pressure rod is welded on the right side of the force transmission plate, and the pressure rod is aligned with the center of the left side of the upper shear box and fits tightly; The strain recording mechanism is provided with a resistance strain gauge, an ultra-dynamic strain gauge and a data acquisition instrument connected by wires; a plurality of resistance strain gauges are pasted on the sample, the resistance strain gauge is connected to the ultra-dynamic strain gauge by wires, and the ultra-dynamic strain gauge is connected to the data acquisition instrument by wires; The receiving mechanism is an impact load receiving mechanism, which is provided with an upper shear box, a lower shear box, two baffles with holes, a pressure plate, a normal static load electric cylinder and a horizontal static load electric cylinder; the upper shear box and the lower shear box form a complete shear box; the holes of the two baffles with holes are both embedded with balls, wherein the first baffle with holes is fixed to the frame partition by screws, and the lower shear box is placed on the first baffle with holes; the upper shear box is installed on the lower shear box, and the sample is installed in the shear box; The upper shear box is provided with a rectangular hole, which provides a wire lead-out channel for the resistance strain gauge pasted on the specimen; the second baffle with holes is also fixed to the upper shear box by screws; the pressure plate is placed on the second baffle with holes, the edge of the pressure plate is aligned with the shear box, and the normal static load electric cylinder is pressed on the pressure plate to apply normal static load pressure to the specimen; the horizontal static load electric cylinder is installed on the right side of the lower shear box to apply horizontal static load pressure to the specimen.

2. The blasting vibration simulation impact device for shear rheology test according to claim 1, characterized in that: The combined plate is used to transfer the impact load to the shear box when the transfer mechanism transfers the impact load, and is used to fix the upper shear box when the impact load is not transferred.

3. The blasting vibration simulation impact device for shear rheology test according to claim 1, characterized in that: The incident rod, the combined plate and the shear box are made of the same material, stainless steel, to ensure that the propagation speed of the vibration wave remains unchanged during the transmission process.

Images