Perspex sheet blasting model test device

Abstract

The utility model relates to the technical field of blasting. The utility model aims to provide an organic glass plate blasting model test device which comprises an organic glass plate, two coated steel plates arranged on the upper side and the lower side of the organic glass plate, and two rubber plates clamped between the coated steel plates and the two sides of the organic glass plate, a plurality of groups of bolt holes are formed in the edges of the two coated steel plates in pairs, and the coated steel plates are tightened by connecting bolts penetrating through the bolt holes; a blast hole used for installing an explosion body is formed in the middle of the organic glass plate, a blocking hole is formed in the position, opposite to the blast hole, of the wrapping steel plate, and a hole blocking steel plug is arranged in the blocking hole. According to the device, the quasi-static effect of detonation gas can be brought into full play, and the device accords with boundary conditions which are generally adopted in practical engineering during reverse detonation, that is, the detonation gas is still located in a blast hole and a crack after detonation and does not overflow, so that a high-pressure state is maintained, and the quasi-static effect is enhanced compared with a conventional organic glass plate blasting test.

Description

Technical Field

[0001] The utility model relates to the technical field of blasting, in particular to an organic glass plate blasting model test device. Background Art

[0002] Both the organic glass plate and the rock are brittle materials, and their failure modes under explosion loads are similar to those of the rock. Therefore, the organic glass plate is often used in blasting model tests. The existing organic glass explosion model tests are usually combined with a dynamic caustics test system and a speckle test system. Both of these methods are premised on the dynamic capture of the organic glass plate by an ultra-high-speed camera. Therefore, usually only the blast holes are blocked by clamps to prevent the explosion-generated gas from overflowing at the blast holes. However, under the action of stress waves, a large number of cracks will be generated in the organic glass plate, providing an overflow channel for the explosion-generated gas, thereby weakening the quasi-static effect of the explosion-generated gas. Moreover, the existing organic glass blasting model test devices are usually indoor tests, the devices are heavy, and usually cannot conduct explosion tests with large amounts of explosives, resulting in various experimental limitations.

[0003] Each main part of the device of the utility model is detachable and assembled, and the device can be flexibly customized according to the actual amount of explosives and the size of the organic glass plate. At the same time, the utility model not only restricts the overflow of the explosion-generated gas at the blast holes, but also restricts the movement of the explosion-generated gas in the direction perpendicular to the organic glass plate after cracks are generated, which highly conforms to the actual situation that the explosion-generated gas remains inside the rock mass after the explosive is detonated from the bottom in actual blasting engineering, and can achieve better blasting simulation.

[0004] Before the utility model, the patent with the patent number CN102539254A provided a digital laser dynamic caustics test method and system. In this system, the polarization effect after the deformation of the organic glass is mainly amplified by laser, and the dynamic process of crack propagation is recorded by a digital high-speed camera, and optical-mechanical analysis can be carried out on the dynamic fracture experimental processes such as impact and blasting. The purpose of this test system and method is different from that of the utility model. The purpose of this experimental system is to capture the dynamic change process of cracks and identify the types of cracks, mainly relying on the light transmission and polarization effect of the organic glass plate. Only the blast holes are blocked by clamps in the test, and the overflow of the explosion-generated gas in the crack area cannot be prevented. Therefore, usually the test results deviate greatly from the actual project, and the quasi-static effect of the explosion-generated gas cannot be fully exerted.

[0005] The patent with the patent number CN215727289U provided an organic glass plate blasting test clamp. The clamp in this utility model can arbitrarily adjust the number, distance and height of the clamp arms, and can meet the requirements of different positions, numbers, plugging effects and stabilities of the blast holes in the organic glass blasting test. However, this clamp can only simply inhibit the overflow of the explosion-generated gas at the blast holes, so its structure still has room for further optimization. Summary of the Invention

[0006] The purpose of the utility model is to provide an organic glass plate blasting model test device, which can fully ensure the quasi-static action of the explosive gas in the organic glass blasting model experiment, so that the test results of the model are more in line with engineering practice.

[0007] To achieve the above invention purpose, the technical solution adopted by the utility model is: an organic glass plate blasting model test device, including an organic glass plate, two covering steel plates arranged on the upper and lower sides of the organic glass plate, and two rubber plates clamped between the covering steel plates and the two sides of the organic glass plate;

[0008] A number of groups of bolt holes are arranged in pairs at the edges of the two covering steel plates, and are tightened by connecting bolts passing through the bolt holes;

[0009] A blast hole for installing an explosive is arranged in the middle of the organic glass plate, a plugging hole is arranged at the position of the covering steel plate opposite to the blast hole, and a plugging steel plug is arranged in the plugging hole; a detonating hole and a center hole are respectively arranged on the plugging steel plug on the upper side of the organic glass plate and the rubber plate, a detonator is installed in the detonating hole, and the detonator extends into the blast hole and is coupled with the explosive;

[0010] It also includes an information acquisition system arranged on the organic glass plate, and the information acquisition system is used to collect the strain information of the organic glass plate after the explosion.

[0011] Preferably, the edges of the covering steel plates extend beyond the organic glass plate and the rubber plates, and the bolt holes are located on the extended parts of the edges of the covering steel plates.

[0012] Preferably, the information acquisition system includes a number of strain gauges pasted on the upper surface of the organic glass plate, and the strain gauges are electrically connected to the test system through connecting wires.

[0013] Preferably, the plugging steel plug and the side wall of the plugging hole are bonded by AB glue.

[0014] Preferably, the thickness of the plugging steel plug is greater than the thickness of the covering steel plate.

[0015] Preferably, a connecting ring is also arranged on the plugging steel plug, and the connecting ring is connected to the fixed foundation on the ground through an insurance chain.

[0016] Preferably, the explosive is a columnar charge filled with emulsion explosive.

[0017] Preferably, the columnar charge is formed by 3D printing.

[0018] Preferably, the connecting bolt is a shear bolt.

[0019] Preferably, the initiator is a digital electronic detonator.

[0020] Preferably, it further includes a support, and the support is pad - set under the lower - side cladding steel plate; the support is a concrete support.

[0021] The beneficial effects of the present utility model are mainly reflected in that,

[0022] 1. It can give full play to the quasi - static effect of the explosion - generated gas, conforming to the boundary conditions in the reverse initiation commonly used in actual engineering, that is, after initiation, the explosion - generated gas remains in the blast hole and cracks instead of overflowing, thus maintaining a high - pressure state, and enhancing the quasi - static effect compared with the conventional organic glass plate blasting test.

[0023] 2. In the present utility model, an insulating rubber plate is used between the organic glass plate and the steel plate, and the rubber plate has the following functions:

[0024] (1) Tightly couples the cladding steel plate and the organic glass plate together, making the stress evenly distributed, preventing local stress concentration and having an adverse effect on the subsequent propagation of explosion - induced cracks;

[0025] (2) Prevents the explosion - generated gas from overflowing and maintains the quasi - static effect of the explosion - generated gas;

[0026] (3) Can protect the connecting wires of the strain gauges, preventing the strong rigid extrusion between the cladding steel plate and the organic glass plate from damaging the connecting wires during blasting;

[0027] (4) Prevents the connecting wires from being directly connected to the steel plate, thus detonating the digital electronic detonator.

[0028] 3. The test device in the present utility model is easy to install, does not require other tools during installation, and the overall device is relatively light, suitable for various sites. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic structural diagram of the present utility model in the assembled state;

[0030] Figure 2 is a schematic structural diagram of the organic glass plate, cladding steel plate and rubber plate of the present utility model before assembly;

[0031] Figure 3 is a schematic installation diagram of the strain gauge on the organic glass plate;

[0032] Figure 4 is a schematic structural diagram of the upper plugging steel plug and the lower plugging steel plug. DETAILED DESCRIPTION OF THE INVENTION

[0033] The technical solution of the present utility model will be further described in detail below with reference to the accompanying drawings. The embodiments described are only a part of the embodiments of the present utility model, rather than all of them, and are intended to facilitate better implementation by those skilled in the art in engineering, rather than limiting the use of the present utility model.

[0034] The purpose of the present utility model is to provide a simple blasting model test device based on an acrylic plate and a corresponding test method. The advantage of this device compared with the existing devices is that it can prevent the spillage of explosion-generated gas in the crack area by changing the boundary conditions, thereby giving full play to the quasi-static effect of the explosion-generated gas. This boundary condition is the same as the boundary condition of the explosion-generated gas after reverse initiation in actual blasting engineering. Therefore, the crack propagation and failure mode caused by it are more in line with the actual engineering.

[0035] As Figure 1 shown, a blasting model test device for an acrylic plate includes an acrylic plate 6. The thickness of the acrylic plate 6 is generally between 0.5 - 3 cm. A blast hole 11 for installing an explosive body 13 is provided in the middle of the acrylic plate 6. For example, the acrylic plate 6 is a square acrylic plate with dimensions of 800 * 800 * 10 mm, and the diameter of the blast hole 11 is 4 cm.

[0036] It also includes two covering steel plates arranged on the upper and lower sides of the acrylic plate 6. For example, its shape is also square, with dimensions of 900 * 900 * 6 mm, which is larger than the size of the acrylic plate 6. For a clearer display, as Figure 1 and 2 shown, the covering steel plate 4 on the upper side and the covering steel plate 8 on the lower side are respectively labeled for display. A plugging hole is provided at the position on the covering steel plate opposite to the blast hole 11. The setting of the plugging hole is to facilitate the filling of the explosive body 13 in the blast hole 11 and also facilitate plugging. As Figure 2 shown, the plugging hole includes a plugging hole 402 on the upper side and a plugging hole 802 on the lower side. A plugging steel plug is provided in the plugging hole, and there are also two plugging steel plugs. As Figure 2 and 4 shown, the plugging steel plug 10 on the upper side and the plugging steel plug 12 on the lower side.

[0037] Under the overall structure of the present utility model, the acrylic plate 6 is clamped by the covering steel plates. Regarding the connection form of the covering steel plates, a number of groups of bolt holes are provided in pairs at the edges of the two covering steel plates, and they are tightened by connection bolts passing through the bolt holes. The connection bolts can be toggle bolts. As Figure 1 and 2As shown in the figure, there are the bolt body 1 and the bolt head 2 of the U-bolt. The installation of the U-bolt is based on being able to exactly form a connection and fixation, and it does not exert vertical stress on the clad steel plate. Regarding the installation position of the U-bolt, the edge of the clad steel plate extends beyond the organic glass plate and the rubber plate, and the bolt holes are located on the extended part of the edge of the clad steel plate. The bolt holes include upper bolt holes 401 on the upper clad steel plate 4 and lower bolt holes 801 on the lower clad steel plate 8. They are arranged in pairs and evenly distributed on the edge of the clad steel plate.

[0038] After the explosion, in order to prevent the plugging steel plug from undergoing large plastic deformation after bearing the explosion load, during design, the thickness of the plugging steel plug is greater than the thickness of the clad steel plate, and it is preferably about twice the thickness of the clad steel plate. In order to ensure the installation stability of the plugging steel plug 12 in the plugging hole, the plugging steel plug and the side wall of the plugging hole are bonded by AB glue. In the test, the plugging steel plate and the steel plate are connected by a soft connection method such as AB glue instead of by welding. After the AB glue is completely hardened, it can provide a shear strength of about 20 MPa, which can ensure the plugging effect while ensuring that the plugging steel plate has separated from the upper and lower clad steel plates before reaching the yield strength. In order to prevent the risk caused by the plugging steel plug being blown away during the explosion, a connecting ring can also be provided on the plugging steel plug, generally a semi-circular ring, which is directly welded on the upper plugging steel plug 10. The connecting ring is connected to the fixed foundation on the ground through an insurance chain to prevent excessive flying during the explosion.

[0039] Another significant difference of the present utility model is that it also includes two rubber plates clamped between the upper and lower sides of the clad steel plate and the organic glass plate 6, as Figure 1 and 2 shown in the figure, which are the upper rubber plate 5 and the lower rubber plate 7 respectively. The rubber plate can (1) tightly couple the clad steel plate and the organic glass plate 6 together, making the stress evenly distributed and preventing local stress concentration, which has an adverse effect on the subsequent propagation of explosion cracks; (2) prevent the explosion-generated gas from overflowing and maintain the quasi-static action of the explosion-generated gas; (3) can protect the connecting wires of the strain gauges and prevent the strong rigid extrusion between the clad steel plate and the organic glass plate from damaging the connecting wires during the explosion moment; (4) prevent the connecting wires from being directly connected to the steel plate, thereby detonating the digital electronic detonator.

[0040] For the convenience of loading and initiating the explosive body 13, an initiating hole 14 and a central hole 501 are respectively provided on the plugging steel plug 10 and the rubber plate on the upper side of the organic glass plate of the present utility model. An initiator 9 is installed in the initiating hole 14, and the initiator 9 extends into the blast hole 11 and is coupled with the explosive body 13; the initiator 9 can be a digital electronic detonator or other initiating components.

[0041] It also includes an information acquisition system disposed on the plexiglass plate. The information acquisition system is connected to the strain test system and is used to acquire the strain information of the plexiglass plate after the explosion. The information acquisition system may include a number of strain gauges pasted on the upper surface of the plexiglass plate, and the strain gauges are electrically connected to the test system through connecting wires.

[0042] Regarding the explosive body 13 used in the present utility model, it is generally a columnar charge tube filled with emulsion explosive. For example: small charge tubes can be prepared by means such as 3D printing or thermoplastic forming in the experimental preparation stage. During the test, the charge tube is pasted at a specified position (the corresponding position preset in the blast hole 11) above the rubber plate 7 on the lower side in the blast hole 11 through 502 glue, and then emulsion explosive is filled into the charge tube to ensure uniform distribution of the explosive.

[0043] In addition, the present utility model is usually provided with a support. That is to say, it also includes a support, and the support is generally a cubic concrete support, which is placed under the lower covering steel plate 8.

[0044] Regarding the usage method of the plexiglass plate blasting model test device of the present utility model, that is, its test method, includes the following steps:

[0045] A. Prepare the lower covering steel plate and the corresponding lower hole plugging steel plug, and bond the hole plugging steel plug in the plugging hole of the lower covering steel plate by using AB glue; ensure that one surface of the lower covering steel plate and the hole plugging steel plug is flat, and wait for the AB glue to completely harden;

[0046] B. Place the support on the ground, and then place the lower covering steel plate flat on the support, with the flat surface facing up. The support should be placed in a way that the support is uniform and stable and can fully expose the bolt holes;

[0047] C. Center and lay the rubber plate flat on the lower covering steel plate, and then center and lay the plexiglass plate flat on the rubber plate;

[0048] D. Paste strain gauges on the upper surface of the plexiglass plate and connect them to the strain test system through connecting wires. The connecting wires should be as thin as possible and the connecting wires should be laid flat to prevent local protrusions from affecting crack propagation;

[0049] E. Center and lay the upper rubber plate flat on the plexiglass plate, so that the central hole on the rubber plate is aligned with the blast hole on the plexiglass plate;

[0050] F. Place the upper covering steel plate on the upper rubber plate, align the bolt holes of the upper covering steel plate and the lower covering steel plate, and use the toggle bolts to tighten the two covering steel plates; in order to prevent the toggle bolts from generating vertical prestress on the plexiglass plate, only tighten the toggle bolts in place without applying tightening force in this step;

[0051] G. Place the explosive body into the blast hole, and then bond the plugging steel plug with a primer hole on the upper side to the plugging hole of the upper covering steel plate through AB glue; after the AB glue is completely hardened, fix it to the ground foundation through the safety chain connecting ring;

[0052] H. Insert the detonator from the primer hole, contact the explosive body, connect the detonation wire to a safe distance, evacuate the crowd outside the warning line, and then start the detonation after adjusting the strain test system to the trigger acquisition state.

[0053] The above embodiments are only the preferred embodiments of the present invention. Those skilled in the art can appropriately modify the technical solutions provided by the present invention according to the actual engineering situation. The modifications and equivalent transformations made do not depart from the scope of protection required by the present invention. The scope of the rights required by the present invention shall be subject to the appended claims.

Claims

1. An experimental device for the blasting model of a plexiglass plate, comprising a plexiglass plate, two covering steel plates arranged on the upper and lower sides of the plexiglass plate, and two rubber plates clamped between the covering steel plates and the two sides of the plexiglass plate; A number of groups of bolt holes are arranged in pairs at the edges of the two covering steel plates, and are tightened by connecting bolts passing through the bolt holes; A blast hole for installing an explosive body is arranged in the middle of the plexiglass plate, a plugging hole is arranged at the position on the covering steel plate opposite to the blast hole, and a plugging steel plug is arranged in the plugging hole; A detonating hole and a central hole are respectively arranged on the plugging steel plug on the upper side of the plexiglass plate and the rubber plate. A detonator is installed in the detonating hole, and the detonator extends into the blast hole and is coupled with the explosive body; It also includes an information acquisition system arranged on the plexiglass plate, and the information acquisition system is used to acquire the strain information of the plexiglass plate after the explosion.

2. The organic glass plate blasting model test device according to claim 1, characterized in that: The edges of the covering steel plates extend beyond the plexiglass plate and the rubber plates, and the bolt holes are located on the extended parts of the edges of the covering steel plates.

3. The organic glass plate blasting model test device according to claim 2, wherein: The information acquisition system includes a number of strain gauges pasted on the upper surface of the plexiglass plate, and the strain gauges are electrically connected to the test system through connecting wires.

4. The organic glass plate blasting model test device according to claim 3, wherein: The plugging steel plug is bonded to the side wall of the plugging hole by AB glue.

5. The organic glass plate blasting model test device according to claim 4, wherein: The thickness of the plugging steel plug is greater than the thickness of the covering steel plate.

6. The organic glass plate blasting model test device according to claim 5, characterized in that: A connecting ring is also arranged on the plugging steel plug, and the connecting ring is connected to the fixed foundation on the ground through a safety chain.

7. The organic glass plate blasting model test device according to claim 6, wherein: The explosive body is a columnar charge filled with emulsion explosive.

8. The organic glass plate blasting model test device according to claim 7, characterized in that: The connecting bolt is a toggle bolt.

9. The organic glass plate blasting model test device according to claim 8, characterized in that: The detonator is a digital electronic detonator.

10. The organic glass plate blasting model test device according to claim 9, wherein: It also includes a support, and the support is placed under the covering steel plate on the lower side; The support is a concrete support.

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