A device and method for testing the impact resistance of a protective material under dynamic loading

Abstract

The present application relates to the technical field of multi-parameter monitoring of rock-soil blasting engineering, in particular to a device for testing the impact resistance of protective materials under dynamic load impact, a load setting structure is arranged on the upper part of the frame body, and the load setting structure comprises a magnetic lifting module and an impact module arranged in a top-bottom manner, the magnetic lifting module comprises an electromagnet and a magnetic chuck with a hole in the middle, the electromagnet is arranged above the fixed plate, the impact module comprises an impact ring, and the outer ring of the impact ring is sleeved on the positioning sleeve; the blast-resistant plate is located directly below the impact ring, and the bottom surface is connected to the lower bottom plate through a second elastic element; the center column is connected to the blast-resistant plate through a clamp at the bottom. The present application also provides a method for testing the impact resistance of protective materials under dynamic load impact, which can realize quantitative testing and evaluation of the impact resistance of protective materials, provide test equipment for the study of the impact resistance of protective materials, and enrich the testing method, and has a wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multi-parameter monitoring of rock-soil blasting engineering, in particular to a device and method for testing the impact resistance of protective materials under dynamic load impact. BACKGROUND

[0002] Due to different blasting scales, methods and environments, blasting can cause different impact velocities, and different shock waves will have different degrees and ranges of influence on surrounding buildings, facilities and personnel. In engineering blasting construction, when a flying stone is ejected outward with great impact force, a protective net can effectively intercept and buffer the energy of the flying stone due to its tough material and close grid structure. The flying stone, which would have caused serious damage, is bound together within a certain range, greatly reducing the probability and degree of harm of accidents.

[0003] Traditional simulation impact devices have fixed clamps, which are not flexible enough, and when testing the impact material properties, there is no situation where tensile force and impact force exist simultaneously, the simulated impact scene is not realistic, and the test results are not representative and one-sided. The structure of the impact is not flexible enough, and multiple loads cannot be simulated during testing. Therefore, there is an urgent need to develop a simulation impact damage test method and device to conduct dynamic response and damage mechanism experimental research on the pre-tightened test block impact of protective materials. It is of great significance to explore the relationship between the pre-tightened state, attribute parameters of protective materials, impact body speed, mass, and the interception performance and damage mechanism of protective materials, and to further improve the impact resistance and interception reliability of protective materials. SUMMARY

[0004] To solve the technical problems existing in the simulation impact damage test, the present application provides a device and method for testing the impact resistance of protective materials under dynamic load impact, which can realize the impact working condition of the sample under different impact forces, change the size and shape of the impact tool, and detect and analyze the dynamic response and damage mechanism of the steel wire rope tension vibration.

[0005] The technical scheme of the present application is as follows:

[0006] A device for testing the impact resistance of protective materials under dynamic load impact, comprising a frame, the frame comprising:

[0007] a fixed plate at the upper end and a bottom plate at the lower part;

[0008] a connecting structure comprising a plurality of positioning sleeves connected between the fixed plate and the bottom plate at the lower part;

[0009] a central column located inside the connecting structure, one end connected to the bottom surface of the fixed plate and the other end extending downward;

[0010] The upper part of the frame body is provided with a load setting structure, including a magnetic lifting module and an impact module arranged upward and downward, the magnetic lifting module includes an electromagnet and a magnetic chuck with a hole in the middle, the electromagnet is arranged above a fixed plate, the fixed plate is elastically connected with the magnetic chuck below through a first elastic member, the impact module includes an impact ring with a hole in the middle, the outer ring of the impact ring is sleeved on a positioning sleeve;

[0011] The lower end of the frame body is provided with a bearing structure, including an anti-explosion plate, the bottom surface of which is connected with a lower bottom plate through a second elastic member; the anti-explosion plate is sleeved on the positioning sleeve and located directly below the impact ring;

[0012] The center column and the anti-explosion plate are connected through a clamp.

[0013] A hydraulic rod is arranged between the anti-explosion plate and the lower bottom plate.

[0014] The second elastic member is a plurality of helical fixed springs.

[0015] The first elastic member is a plurality of detachable helical springs.

[0016] A plurality of hooks are arranged on the opposite surfaces of the fixed plate and the magnetic chuck, for detachable connection of the detachable helical springs.

[0017] A plurality of positioning sleeves are arranged in a ring shape at the middle position of the frame body, a plurality of guide rods are arranged outside the positioning sleeves, a high-speed camera is installed on the guide rods, and a speed sensor is arranged beside the anti-explosion plate.

[0018] The clamp is arranged on the bottom surface of the center column and the upper surface of the anti-explosion plate respectively, and the two are arranged oppositely, the clamp includes:

[0019] A fastening sleeve is internally threadedly connected with a clamping arm;

[0020] The clamping arm is divided into a first clamping part and a second clamping part which are the same in structure and are arranged symmetrically left and right, the outer arc is a minor arc, the opposite surfaces are arranged in parallel, and grooves are arranged on the opposite surfaces of the clamping arm.

[0021] The clamping block is divided into two parts arranged symmetrically left and right, and the sample is detachably fixed in the groove.

[0022] The device is also provided with a display output structure, including a first terminal and a second terminal, the first terminal is electrically connected with the high-speed camera to generate a speed strain curve, and the second terminal is electrically connected with the clamp to generate a resistivity change curve.

[0023] A method for testing the impact resistance of protective materials under dynamic load impact, using a dynamic load impact protective material impact resistance testing device as described above, including the following steps:

[0024] S1: installing the device;

[0025] To energize the electromagnet, a detachable coil spring is hung under the fixed plate, and the control of the electromagnet on the compression Δx of the coil spring is energized and debugged;

[0026] S2: Install the sample on the clamp between the center column bottom and the anti-blast plate, and keep it in tension state;

[0027] S3: Calculate the number n of detachable coil springs, the compression amount Δx, and the mass m of the impact ring required for the sample to reach the required speed;

[0028] S3.1: Ignore friction, and the detachable coil spring is a light spring. When the detachable coil spring is compressed by Δx, calculate the elastic potential energy converted into kinetic energy of the impact ring when the detachable coil spring returns to its original length;

[0029] Get the speed of the impact ring given by the detachable coil spring ;

[0030] S3.2: Calculate the speed of the impact ring obtained by free fall ;

[0031] Then the speed of the impact ring when it separates from the magnetic chuck is: ;

[0032] By changing the required height Δx, the number n of detachable coil springs, and the mass m of the impact ring, the detection speed can be achieved;

[0033] S4: Install n detachable coil springs and a specified mass impact ring, and install the sample;

[0034] S5: Energize the high-speed camera and the speed sensor. If the sample is an insulating material, connect the first terminal; if the sample is a conductive material, connect the first terminal and the second terminal;

[0035] S6: Turn off the power, demagnetize the electromagnet, release the impact ring, and complete one impact;

[0036] S7: Record the data through the monitoring equipment and save it;

[0037] The high-speed camera captures the changes on the surface of the sample when the impact ring impacts the anti-blast plate; the speed sensor detects the speed of the impact ring falling to the anti-blast plate, and inputs the difference between the detected speed and the speed into the first terminal, generating a speed-strain curve; if the sample is a conductive material, the second terminal generates a resistivity change curve of the sample.

[0038] S8: After disassembling the clamp, take out the sample; adjust the compression length Δx of the detachable coil spring and replace the number n of detachable coil springs;

[0039] Repeat S1 to S8, continue the next test until all the predetermined impact speed, analysis of all data, summarize the impact of the speed of the resistivity of the conductive material.

[0040] A method for testing the impact resistance of a protective material under dynamic load impact, using a device for testing the impact resistance of a protective material under dynamic load impact as described above, comprising the following steps:

[0041] S1: Install the device;

[0042] Power on the electromagnet, hang a detachable coil spring under the fixed plate, power on and adjust the control of the electromagnet on the compression Δx of the coil spring;

[0043] S2: Install the sample on the clamp between the center column bottom and the blast plate, and keep it in tension;

[0044] Set the tension of the hydraulic rod;

[0045] S3: Calculate the number of detachable coil springs n, compression Δx, and impact ring mass m required for the sample to reach the desired speed;

[0046] S3.1: Ignore friction and the detachable coil spring is a lightweight spring, calculate the elastic potential energy of the detachable coil spring when it returns to its original length, which is converted into kinetic energy of the impact ring;

[0047] Get the speed of the impact ring given by the detachable coil spring ;

[0048] S3.2: Calculate the speed of the impact ring free fall ;

[0049] Then the speed of the impact ring when it separates from the magnetic disc is: ;

[0050] Change the required height Δx, the number of detachable coil springs n, and the mass of the impact ring m to achieve the detection speed;

[0051] S4: Install n detachable coil springs and a specified mass impact ring, and install the sample;

[0052] S5: Power on the high-speed camera and speed sensor, if the sample is an insulating material, connect the first terminal; if the sample is a conductive material, connect the first terminal and the second terminal;

[0053] S6: Power off, demagnetize the electromagnet, release the impact ring, and complete one impact;

[0054] S7: Record and save the data through the monitoring equipment;

[0055] The high-speed camera shoots the surface change of the sample when the impact ring impacts the anti-blast plate; the speed sensor detects the speed of the impact ring falling to the anti-blast plate and the difference value of the detected speed, and inputs the first terminal to generate a speed strain curve; if the sample is a conductive material, the second terminal generates a sample resistivity change curve.

[0056] S8: After the clamp is disassembled, the sample is taken out; the compression length Δx of the detachable coil spring is adjusted, and the number n of the detachable coil spring is replaced.

[0057] Compared with the existing device for simulating impact effect, the present application has the following advantages:

[0058] The unique detachable clamp design can conveniently clamp different types of samples, and the design of the detachable and replaceable component increases flexibility;

[0059] The impact ring is indirectly controlled by the electromagnet, and the controllability is higher, and the hydraulic rod can better simulate the impact effect; the impact height of the impact module, the number of springs and the mass of the impact ring can be flexibly adjusted to adjust the size of the impact speed, so as to investigate the influence of the impact speed on the sample and guide the effective use of the blast impact protection structure of the sample material;

[0060] The design of the impact ring impacting the anti-blast plate makes the stress of the anti-blast plate more uniform, prevents uneven stress, and makes the test result inaccurate; and the impact path of the impact ring is fixed by the positioning sleeve to ensure the accurate position of the falling point;

[0061] (4) The hydraulic rod fixes the tension, simulates the case that the material is first stretched and then impacted under real working conditions, has high automation degree, simple operation and good test repeatability;

[0062] (5) The development of the device is a beneficial supplement to the existing test of the impact resistance of protective materials, enriches the related test methods, can realize quantitative and qualitative test of the impact resistance of protective materials, can carry out comprehensive evaluation of the impact resistance of traditional stress, strain and resistivity and other indicators, and provides infrastructure support for the impact resistance test of new protective materials;

[0063] (6) The overall test based on the device is easy to operate, easy to implement, simple and fast, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0064] In the drawings:

[0065] Figure 1 is a schematic diagram of the overall effect of the present application;

[0066] Figure 2 is a schematic diagram of part of the structure of the present application;

[0067] Figure 3 Part structure schematic diagram of the present application;

[0068] Figure 4 Clamp structure schematic diagram of the present application;

[0069] Figure 5 Part cross-sectional view of the clamp of the present application;

[0070] Figure 6 Part structure schematic diagram of the present application;

[0071] Figure 7 Part structure schematic diagram of the present application;

[0072] Figure 8 Auxiliary schematic diagram of the calculation process;

[0073] Figure 9 Flowchart of the impact resistance test method of the present application;

[0074] Figure 10 Flowchart of the impact resistance test method of the present application under simulated real working conditions;

[0075] Figure 11 Flowchart of the tensile resistance test method of the present application.

[0076] Components represented by each reference numeral in the drawings are:

[0077] 1, load setting structure; 11, electromagnet; 12, magnetic chuck; 13, impact ring; 14, lower bottom plate; 2, frame body; 201, fixed plate; 202, lifting hook; 203, detachable coil spring; 204, positioning sleeve; 205, fixed upright post; 206, limiting block; 207, guide rod; 208, clamp; 2081, clamping arm; 2082, fastening sleeve; 2083, clamping block; 2084, sample through hole; 209, central upright column; 210, high-speed camera; 3, bearing structure; 31, cylinder; 32, coil fixing spring; 33, speed sensor; 34, anti-explosion plate; 35, hydraulic rod; 36, hydraulic top plate; 4, protection structure; 41, load protection shell; 42, pedestal protection shell; 5, display output structure; 51, first terminal; 52, second terminal; 6, sample. DETAILED DESCRIPTION

[0078] The technical solution of the present application is as follows:

[0079] Referring to Figure 1 and Figure 2 A protective material impact resistance test device under dynamic load impact, comprising a frame body 2, the frame body 2 comprises:

[0080] The fixed plate 201 at the upper end and the lower bottom plate 14;

[0081] The connecting structure comprises a plurality of positioning sleeves 204 connected between the fixed plate 201 and the lower base plate 14.

[0082] A central column 209 is located inside the connecting structure, one end of which is connected to the bottom surface of the fixed plate 201, and the other end extends downward.

[0083] A fixed column 205 is further provided between the fixed plate 201 and the lower base plate 14, which is divided into left and right two parts, used for fixing the overall device, and is connected to the fixed plate 201 through threads, supporting the fixed plate 201, satisfying the sample 6 stress and shrinkage process column without deformation and shaking.

[0084] The upper part of the frame body 2 is provided with a load setting structure 1, which comprises a magnetic lifting module and an impact module arranged above and below. The magnetic lifting module comprises an electromagnet 11 and a magnetic chuck 12 with a hole in the middle. The electromagnet 11 is arranged above the fixed plate 201, and the magnetic chuck 12 is connected to the fixed plate 201 through the first elastic element below the fixed plate 201. The impact module comprises an impact ring 13 with a hole in the middle, and the outer ring of the impact ring 13 is sleeved on the positioning sleeve 204.

[0085] The first elastic element is a plurality of detachable coil springs 203. Figure 3 The opposite surface of the fixed plate 201 and the magnetic chuck 12 is provided with a plurality of hooks 202, which are used to realize the detachable connection of the detachable coil springs 203.

[0086] The lower end of the frame body 2 is provided with a bearing structure 3, which comprises an anti-explosion plate 34 connected to the lower base plate 14 through the second elastic element. The anti-explosion plate 34 is sleeved on the positioning sleeve 204 and located directly below the impact ring 13.

[0087] The second elastic element is a plurality of coil fixing springs 32, which are movably connected to the lower base plate 14. The coil fixing springs 32 are used to buffer the speed after the impact of the impact ring 13.

[0088] Further, the coil fixing spring 32 can be connected to the lower base plate 14 through threads or through a connecting piece.

[0089] The anti-explosion plate 34 is provided with a cylinder 31, and a hydraulic rod 35 is provided between the anti-explosion plate 34 and the lower base plate 14. The main body of the hydraulic rod 35 is composed of three rod bodies which can be relatively slidably sleeved, and sealing structures are provided between the rod bodies. The hydraulic rod 35 passes through the anti-explosion plate 34, and the hydraulic rod 35 is connected to the hydraulic rod 35 at the top of the anti-explosion plate 34 by a hydraulic top plate 36.

[0090] The hydraulic drive device comprises a hydraulic pump, a hydraulic cylinder and a hydraulic pipeline connecting the two. The hydraulic cylinder is connected to the main body of the hydraulic rod 35 for transmission.

[0091] The hydraulic rod 35 is controlled by a microcomputer control system, including a microprocessor, sensors for monitoring the position of the lifting rod body and load pressure information in real time, and a control circuit for transmitting the monitoring data to the microprocessor. The microprocessor controls the start-stop, rotation speed and flow direction of the hydraulic pump through the control circuit according to the preset program and the received data, so as to accurately control the lifting height and speed of the hydraulic rod 35 and give the sample 6 a certain pulling force.

[0092] The sample 6 is connected between the bottom of the center column 209 and the blast plate 34 through the clamp 208, and the clamp 208 is welded with the bottom of the center column 209 and the blast plate 34.

[0093] The clamp 208 is provided with one on the bottom surface of the center column 209 and the upper surface of the blast plate 34 respectively, and the two are oppositely arranged. The clamp 208 comprises:

[0094] A fastening sleeve 2082 is internally screwed with a clamping arm 2081;

[0095] In combination Figure 4 For easy understanding, the clamping arm 2081 is divided into a first clamping part and a second clamping part which are symmetrically arranged, and the outer arc is a poor arc, and the opposite surfaces are parallelly arranged, and the opposite surfaces of the clamping arm 2081 are provided with front and rear grooves; the outer surface of the clamping arm 2081 is screwed with the fastening sleeve 2082;

[0096] The poor arcs between the first clamping part and the second clamping part form a sample through hole 2084, such as Figure 5 , for the sample 6 and the resistivity detection lead wire to pass through.

[0097] A clamping block 2083 is divided into two parts which are symmetrically arranged, and can detachably fix the sample 6 in the groove. The clamping block 2083 is made of conductive material, and the opposite surfaces are serrated. At the same time, the clamping block 2083 can be replaced when it is worn out, and the clamping block 2083 of appropriate size can be replaced according to different specifications of the sample 6 to keep the sample 6 firmly clamped.

[0098] A plurality of positioning sleeves 204 are annularly arranged at the middle position of the frame body 2 to limit the vertical movement of the magnetic suction disc 12; a plurality of guide rods 207 are located outside the positioning sleeve 204, and a high-speed camera 210 is installed on the guide rod 207. The high-speed camera 210 can change position through the limiting block 206 on the guide rod 207, and the speed sensor 33 is located beside the blast plate 34, and the position is as shown in Figure 6 and Figure 7 schematic diagram; the frame rate of the high-speed camera 210 is above 1000fps, which is used to shoot the deformation of the sample 6 in the impact process of the impact ring 13, and the vibration displacement waveform of the sample 6 is obtained through video analysis in the later stage.

[0099] The application also provides a display output structure 5, which comprises a first terminal 51 and a second terminal 52, the first terminal 51 is electrically connected with the high-speed camera 210 to generate a speed strain curve, and the second terminal 52 is electrically connected with the clamp 208 to generate a resistivity change curve.

[0100] The device also comprises a protection structure 4, which comprises a load protection shell 41 and a pedestal protection shell 42, and is respectively sleeved outside the load arrangement structure 1 and the bearing structure 3 to protect the internal structure.

[0101] Reference Figure 9 The flowchart is a method for testing the impact resistance of a protective material under dynamic load impact, which adopts the device for testing the impact resistance of a protective material under dynamic load impact, and comprises the following steps:

[0102] S1: installing the device;

[0103] The electromagnet 11 is powered on, one detachable coil spring 203 is hung below the fixed plate 201, and the control of the electromagnet 11 on the compression Δx of the coil spring is powered on and debugged;

[0104] S2: installing the sample 6 on the clamp 208 between the bottom of the center column 209 and the blast plate 34 and keeping the sample 6 in a stretched state;

[0105] S3: obtaining the number n of the detachable coil springs 203, the compression amount Δx and the mass m of the impact ring 13 required for the sample 6 to reach the required speed through calculation;

[0106] S3.1: ignoring friction and regarding the detachable coil spring 203 as a light spring, the elastic potential energy of the detachable coil spring 203 is completely converted into the kinetic energy of the impact ring 13 when the detachable coil spring 203 is compressed by Δx and returns to the original length;

[0107] The speed of the impact ring 13 given by the detachable coil spring 203 is obtained ;

[0108] S3.2: calculating the speed of the impact ring 13 obtained by free fall ;

[0109] Then, the speed of the impact ring 13 when separating from the magnetic suction disc 12 is: ;

[0110] The detection speed is achieved by changing the required height Δx, the number n of the detachable coil springs 203 and the mass m of the impact ring 13;

[0111] S4: installing n detachable coil springs 203 and a specified mass impact ring 13, and installing the sample 6;

[0112] S5: power on the high-speed camera 210 and the speed sensor 33, if the sample 6 is an insulating material, connect the first terminal 51; if the sample 6 is a conductive material, connect the first terminal 51 and the second terminal 52;

[0113] S6: power off, demagnetize the electromagnet 11, release the impact ring 13, and complete one impact;

[0114] S7: record data through the monitoring device and save;

[0115] The high-speed camera 210 captures the surface changes of the sample 6 when the impact ring 13 impacts the anti-blast plate 34; the speed sensor 33 detects the speed of the impact ring 13 falling to the anti-blast plate 34, and inputs the first terminal 51 with the difference between the detected speed, generating a speed-strain curve; if the sample 6 is a conductive material, the second terminal 52 generates a resistivity change curve of the sample 6.

[0116] S8: after disassembling the clamp 208, take out the sample 6; adjust the compression length Δx of the detachable coil spring 203 and replace the number n of the detachable coil spring 203;

[0117] Repeat S1 to S8 to continue the next test until all the predetermined impact speeds are tested, analyze all the data, and summarize the impact of the impact speed on the resistivity of the conductive material.

[0118] The speed of the impact ring 13 given by the detachable coil spring 203 is obtained , the specific solving method is as follows:

[0119] ,

[0120] where, is the elastic potential energy, is the kinetic energy, and k is the elastic coefficient of the detachable coil spring 13.

[0121] The solving formula of is:

[0122] ,

[0123] where, is the time needed for the detachable coil spring 203 to recover to its original length, is the recovery amount of the detachable coil spring 203, which is combined with Figure 8 to help understand;

[0124] The speed solving process of the impact ring 13 in the process of free fall is:

[0125] ,

[0126] ,

[0127] wherein, is the distance from the original length of the detachable coil spring 203 to the falling onto the anti-blast plate 34, here combined with Figure 8 It is helpful to understand that t is the time from the original length of the detachable coil spring 203 to the falling onto the anti-blast plate 34, is the final speed of the impact ring 13.

[0128] Reference Figure 10 Flow chart, a method for testing the impact resistance of a protective material under dynamic load impact, using a device for testing the impact resistance of a protective material under dynamic load impact as described above, comprising the following steps:

[0129] S1: install the device;

[0130] Electrify the electromagnet 11, hang one detachable coil spring 203 under the fixed plate 201, and adjust the control of the electromagnet 11 on the compression Δx of the coil spring;

[0131] S2: install the sample 6 on the clamp 208 between the bottom of the central column 209 and the anti-blast plate 34, and keep it in a stretched state;

[0132] Set the tension of the hydraulic rod 35;

[0133] S3: calculate the number n of detachable coil springs 203, the compression amount Δx, and the mass m of the impact ring 13 required for the sample 6 to reach the required speed;

[0134] S3.1: ignore friction, and the detachable coil spring 203 is a light spring, the detachable coil spring 203 is compressed by Δx, and the elastic potential energy of the detachable coil spring 203 is fully converted into the kinetic energy of the impact ring 13 when it returns to its original length;

[0135] The speed v of the impact ring 13 given by the detachable coil spring 203 ;

[0136] S3.2: calculate the speed v of the impact ring 13 obtained by free fall ;

[0137] Then the speed of the impact ring 13 when it separates from the magnetic suction disc 12 is: ;

[0138] The detection speed is achieved by changing the required height Δx, the number n of detachable coil springs 203, and the mass m of the impact ring 13;

[0139] S4: install n detachable coil springs 203 and a specified mass impact ring 13, and install the sample 6;

[0140] S5: power on the high-speed camera 210 and the speed sensor 33, if the sample 6 is an insulating material, connect the first terminal 51; if the sample 6 is a conductive material, connect the first terminal 51 and the second terminal 52;

[0141] S6: power off, demagnetize the electromagnet 11, release the impact ring 13, and complete one impact;

[0142] S7: record data through the monitoring device and save;

[0143] The high-speed camera 210 shoots the surface change of the sample 6 when the impact ring 13 impacts the anti-blast plate 34; the speed sensor 33 detects the speed of the impact ring 13 falling to the anti-blast plate 34 and the difference value with the detected speed, inputs the first terminal 51, and generates a speed strain curve; if the sample 6 is a conductive material, the second terminal 52 generates a resistivity change curve of the sample 6.

[0144] S8: after the clamp 208 is disassembled, the sample 6 is taken out; the compression length Δx of the detachable coil spring 203 is adjusted, and the number n of the detachable coil spring 203 is replaced.

[0145] Reference Figure 11 The flowchart, the present application can also test the tensile capacity of the sample, and the test method is as follows:

[0146] S1: install the device;

[0147] S2: install the sample 6 on the clamp 208 between the bottom of the center column 209 and the anti-blast plate 34, and keep the tensile state;

[0148] S3: power on the high-speed camera 210 and the speed sensor 33, if the sample 6 is an insulating material, connect the first terminal 51; if the sample 6 is a conductive material, connect the first terminal 51 and the second terminal 52;

[0149] S4, set the tension of the hydraulic rod 35;

[0150] S5, start the hydraulic rod 35 to start applying tension;

[0151] S6: record data through the monitoring device and save;

[0152] The high-speed camera 210 shoots the surface change of the sample 6; inputs the first terminal 51 to display the change process of the sample 6; if the sample 6 is a conductive material, the second terminal 52 generates a resistivity change curve of the sample 6;

[0153] S7: collect data and repeat experiments to analyze the influence of tension on the sample 6.

[0154] The principle adopted by the present application to solve its technical problems is that the blasting impact protection material device mainly comprises a frame body 2, a load setting structure 1, a bearing structure 3, a protection structure 4 and a display output structure 5. The load setting structure 1 is located at the top of the whole, and the impact size of the test sample 6 is adjusted through the impact height, spring stiffness coefficient and mass of the load setting structure 1; to simulate the real blasting working condition.

Claims

1. A device for testing the impact resistance of a protective material under dynamic loading, characterized in that, The frame body (2) comprises: An electromagnet (11) at the upper end and a lower base plate (14); A connecting structure comprising a plurality of positioning sleeves (204) connected between the fixed plate (201) and the lower base plate (14); A plurality of positioning sleeves (204) are arranged in the middle position of the frame body (2), and a plurality of guide rods (207) are arranged outside the positioning sleeves (204), and a high-speed camera (210) is mounted on the guide rod (207), and a speed sensor (33) is arranged beside the blast-resistant plate (34); A central column (209) is arranged inside the connecting structure, one end of the central column (209) is connected to the bottom surface of the fixed plate (201), and the other end of the central column (209) extends downward; A load setting structure (1) is arranged at the upper part of the frame body (2), comprising a magnetic lifting module and an impact module arranged above and below, the magnetic lifting module comprises an electromagnet (11) and a magnetic chuck (12) with a hole in the middle, the electromagnet (11) is arranged above the fixed plate (201), the magnetic chuck (12) is elastically connected below the fixed plate (201) through a first elastic member, the impact module comprises an impact ring (13) with a hole in the middle, and the impact ring (13) is sleeved on the positioning sleeve (204); A bearing structure (3) is arranged at the lower end of the frame body (2), comprising a blast-resistant plate (34), the bottom surface of the blast-resistant plate (34) is connected to the lower base plate (14) through a second elastic member; the blast-resistant plate (34) is sleeved on the positioning sleeve (204) and located directly below the impact ring (13); The central column (209) is connected to the sample (6) through a clamp (208) between the bottom of the central column (209) and the blast-resistant plate (34); A display output structure (5) comprising a first terminal (51) and a second terminal (52), the first terminal (51) is electrically connected with the high-speed camera (210) to generate a speed strain curve; the second terminal (52) is electrically connected with the clamp (208) to generate a resistivity change curve.

2. The apparatus of claim 1, wherein The blast-resistant plate (34) and the lower base plate (14) are provided with a hydraulic rod (35).

3. The apparatus of claim 1, wherein The second elastic member is a plurality of helical fixed springs (32).

4. The apparatus of claim 1, wherein The first elastic member is a plurality of detachable helical springs (203).

5. The apparatus of claim 4, wherein The fixed plate (201) and the magnetic chuck (12) are provided with a plurality of hooks (202) on the opposite surfaces, which are used to realize the detachable connection of the detachable helical springs (203).

6. The apparatus of claim 1, wherein The clamp (208) is arranged on the bottom surface of the central column (209) and the upper surface of the blast-resistant plate (34) respectively, and the two are arranged opposite to each other, and the clamp (208) comprises: A fastening sleeve (2082) internally threaded with a clamping arm (2081); The clamping arm (2081) is divided into a first clamping part and a second clamping part which are the same in structure and are arranged symmetrically left and right, the outer arc is a poor arc, and the opposite surfaces are arranged in parallel, and a front and rear through groove is formed in the opposite surfaces of the clamping arm (2081); A clamping block (2083) is divided into two parts arranged symmetrically left and right, and the sample (6) is detachably fixed in the groove.

7. A method for testing the impact resistance of a protective material under dynamic loading using a device for testing the impact resistance of a protective material under dynamic loading according to any one of claims 1, 3-6, characterized in that, The steps are as follows: S1: installing the device; The electromagnet (11) is powered on, one detachable helical spring (203) is hung below the fixed plate (201), and the control of the electromagnet (11) on the compression Δx of the helical spring is powered on and adjusted; S2: Install the sample (6) on the clamp (208) between the bottom of the center column (209) and the anti-blast plate (34), and keep it in tension state; S3: Calculate the number n of the detachable coil spring (203), the compression amount Δx, and the mass m of the impact ring (13) required for the sample (6) to reach the required speed; S3.1: Ignore friction, and the detachable coil spring (203) is a light spring. When the detachable coil spring (203) is compressed by Δx, calculate the elastic potential energy converted into the kinetic energy of the impact ring (13) when the detachable coil spring (203) returns to its original length; Obtain the speed v0 of the impact ring (13) given by the detachable coil spring (203); S3.2: Calculate the speed v1 obtained by the free fall of the impact ring (13); Then the speed of the impact ring (13) and the magnetic suction disc (12) is separated: v2=v0+v1; By changing the required height Δx, the number n of the detachable coil spring (203), and the mass m of the impact ring (13), the speed can be detected; S4: Install n detachable coil springs (203) and impact rings (13) of a specified mass, and install the sample (6); S5: Power on the high-speed camera (210) and the speed sensor (33). If the sample (6) is an insulating material, connect the first terminal (51); if the sample (6) is a conductive material, connect the first terminal (51) and the second terminal (52); S6: Power off, demagnetize the electromagnet (11), release the impact ring (13), and complete one impact; S7: Record the data through the monitoring equipment and save it; The high-speed camera (210) captures the surface changes of the sample (6) when the impact ring (13) impacts the anti-blast plate (34); the speed sensor (33) detects the speed of the impact ring (13) falling to the anti-blast plate (34), inputs the first terminal (51), and generates a speed-strain curve; if the sample (6) is a conductive material, the second terminal (52) generates a resistivity change curve of the sample (6); S8: After disassembling the clamp (208), take out the sample (6); adjust the compression length Δx of the detachable coil spring (203) and replace the number n of the detachable coil spring (203); Repeat S1 to S8 to continue the next test until all the predetermined impact speeds are tested, analyze all the data, and summarize the impact of the impact speed on the resistivity of the conductive material.

8. A method for testing the impact resistance of a protective material under dynamic loading using a device for testing the impact resistance of a protective material under dynamic loading according to any one of claims 2, characterized in that Including the following steps: S1: Install the device; Power on the electromagnet (11), hang one detachable coil spring (203) under the fixed plate (201), power on and debug the electromagnet (11) to control the compression Δx of the coil spring; S2: Install the sample (6) on the clamp (208) between the bottom of the center column (209) and the anti-blast plate (34), and keep it in tension state; Set the tension of the hydraulic rod (35); S3: Calculate the number n of the detachable coil spring (203), the compression amount Δx, and the mass m of the impact ring (13) required for the sample (6) to reach the required speed; S3.1: Ignoring friction, and the detachable coil spring (203) is a light spring, the detachable coil spring (203) is compressed Δx, and the elastic potential energy is completely converted into the kinetic energy of the impact ring (13) when the detachable coil spring (203) restores to its original length; Obtain the speed v0 given by the detachable coil spring (203) to the impact ring (13); S3.2: Calculate the free-fall speed v1 of the impact ring (13); Then the speed of the impact ring (13) and the magnetic chuck (12) is separated: v2=v0+v1; By changing the required height Δx, the number of detachable coil springs (203) n, and the mass m of the impact ring (13), the speed can be detected; S4: Install n detachable coil springs (203) and a specified mass impact ring (13), and install the sample (6); S5: Power on the high-speed camera (210) and the speed sensor (33), and if the sample (6) is an insulating material, connect the first terminal (51); if the sample (6) is a conductive material, connect the first terminal (51) and the second terminal (52); S6: Power off, demagnetize the electromagnet (11), release the impact ring (13), and complete one impact; S7: Record the data through the monitoring device and save it; The high-speed camera (210) shoots the surface changes of the sample (6) when the impact ring (13) impacts the anti-blast plate (34); the speed sensor (33) detects the speed of the impact ring (13) falling to the anti-blast plate (34), inputs the first terminal (51), and generates a speed strain curve; if the sample (6) is a conductive material, the second terminal (52) generates a resistivity change curve of the sample (6); S8: After disassembling the clamp (208), take out the sample (6); adjust the compression length Δx of the detachable coil spring (203), and replace the number n of detachable coil springs (203).

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