Testing instrument for testing bursting and puncturing strength of membrane material based on triaxial shear apparatus
By modifying the triaxial shear force meter into a membrane material clamp, and combining it with a computer and data acquisition device, the problems of high cost and inaccurate data of existing equipment were solved, and automated control and accurate data acquisition for membrane material puncture and burst tests were realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANJIN UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2026-03-20
- Publication Date
- 2026-05-05
AI Technical Summary
Existing puncture and burst testing equipment has high purchase costs, low resource utilization, and the sample is prone to slippage or damage during clamping and testing, resulting in data distortion. The equipment also lacks safety protection and automated control capabilities.
Using a triaxial shear force meter as the main body, it is modified into a membrane clamp, combined with a computer, data acquisition instrument and special clamping components, and a buffer structure and sensors are added to achieve automated control and accurate data acquisition.
It effectively expands the testing range of the triaxial shear tester, ensures the accuracy and safety of test data, avoids equipment overload, and enables flexible switching between membrane puncture and burst tests.
Smart Images
Figure CN121978001A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of testing equipment for the physical properties of geosynthetics and building membranes, specifically a testing instrument based on a triaxial shear tester for testing the puncture and burst strength of membranes. Background Technology
[0002] With the increasingly widespread application of geomembranes and architectural membranes in water conservancy seepage prevention, railway subgrades, and various membrane structure buildings, membrane materials often face the effects of sharp object compression or localized concentrated loads in actual working conditions. Therefore, conducting puncture and burst strength tests on membrane materials according to relevant testing procedures is a crucial step in ensuring project quality and safety. The current conventional testing method involves fixing the membrane sample in a ring clamp and using a testing machine to drive the jacking rod upwards at a constant speed until the sample fails.
[0003] However, in actual testing work, existing specialized puncture and burst test equipment is often expensive and has relatively limited functions. For most laboratories that are already equipped with general geotechnical testing equipment, purchasing such specialized instruments separately not only creates a high economic burden, but also prevents the effective expansion and utilization of existing equipment such as triaxial shear apparatus when idle, resulting in a waste of resources.
[0004] When using conventional equipment or simple tooling for testing, the sample is prone to slippage when subjected to high-intensity top pressure loads due to the crude design of the clamping mechanism, or it may suffer local damage due to the hard contact of the clamp during the initial installation and fixing stage. This non-stress-induced damage directly affects the accuracy and reproducibility of the final test data.
[0005] In addition, traditional equipment has shortcomings in terms of automated control and safety protection mechanisms. It is difficult to achieve sensitive pressure sensing and drive shutdown at the moment when the membrane material reaches its limit strength and ruptures. This not only limits the accuracy of data acquisition, but also increases the risk of equipment damage due to overload and loss of control. Summary of the Invention
[0006] To address the shortcomings of existing technologies, this invention provides a testing instrument based on a triaxial shear force meter for testing the puncture and burst strength of membrane materials. This instrument solves the problems of high purchase cost and low resource utilization of existing puncture and burst testing equipment, easy slippage or damage to the sample during clamping and testing leading to data distortion, and lack of safety protection mechanisms and automated precise control capabilities.
[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: a testing instrument based on a triaxial shear force meter for testing the puncture and burst strength of membrane materials, comprising a computer, a data acquisition instrument, and a support base. Two lead screws are fixedly connected to the top of the support base, and an upper top seat is fixedly connected to the top of the lead screws. A pressure detection component is provided at the bottom of the upper top seat. A pressure circular top seat is slidably connected to the top of the support base, and a pressure chamber base is provided at the top of the pressure circular top seat. A groove is provided at the bottom of the pressure chamber base. The pressure chamber base is fixedly connected to the top of multiple disc support cylinders. Each disc support cylinder is equipped with a fixing component at its top. Each disc support cylinder is fixedly connected to a fixed disc support rod at its top. A pressure chamber top seat is provided on the outer wall of the fixed disc support rod. A top rod is fixedly connected to the top of the pressure chamber top seat. A force application component is provided at the bottom of the pressure chamber top seat. A buffer component is provided on the outer wall of each fixed disc support rod. An adjustment component is provided on the top of the support base. A drive component is provided inside the support base.
[0008] Preferably, the pressure detection assembly includes a pressure ring, a pressure gauge, and a pressure needle. The top of the pressure ring is fixedly connected to the outer wall of the pressure gauge, the top of the pressure gauge is fixedly connected to the bottom of the upper seat, and the top of the pressure needle is fixedly connected to the bottom of the pressure gauge.
[0009] Preferably, the fixing component includes an upper fixing disc and a lower fixing disc, the inner wall of the upper fixing disc is slidably connected to the outer wall of the fixing disc support rod, the inner wall of the lower fixing disc is slidably connected to the outer wall of the fixing disc support rod, and the bottom of the upper fixing disc is slidably connected to the top of the lower fixing disc.
[0010] Preferably, the force-applying component includes a puncture head and a top-piercing head, and a universal interface is provided at the bottom of the pressure chamber top seat. The universal interface can be connected to the puncture head or the top-piercing head according to different test conditions.
[0011] Preferably, each of the buffer components includes a clamping nut and a buffer nut, the inner wall of the clamping nut being threaded to the top of the fixed disc support rod, the inner wall of the buffer nut being threaded to the outer side of the fixed disc support rod, and the buffer nut being located at the bottom of the pressure chamber top seat.
[0012] Preferably, the adjustment assembly includes a lifting mechanism and a changing mechanism. The lifting mechanism includes a coarse adjustment calibration compass and a fine adjustment calibration compass. The coarse adjustment calibration compass is rotatably connected to one side of the top of the support base, and the fine adjustment calibration compass is rotatably connected to one side of the top of the support base adjacent to the coarse adjustment calibration compass.
[0013] Preferably, the changing mechanism includes a conversion locking lever, one end of which is rotatably connected to the top of the support base on the same side as the fine-tuning calibration compass. A coarse adjustment indicator is provided on one side of the conversion locking lever, and a fine adjustment indicator is provided on the opposite side of the coarse adjustment indicator.
[0014] Preferably, the drive assembly includes a drive motor, a sensor, and a base speed distribution box. The outer wall of the drive motor is fixedly connected to the inside of the base speed distribution box. The output end of the drive motor is connected to the bottom end of the pressure circular top seat. The outer wall of the sensor is fixedly connected to the inside of the base speed distribution box. The top of the base speed distribution box is fixedly connected to the inner wall of the support seat.
[0015] Preferably, the computer and the data acquisition instrument are electrically connected, with one end of the data acquisition instrument electrically connected to the output terminal of the pressure gauge and the other end of the data acquisition instrument electrically connected to the output terminal of the sensor.
[0016] Preferably, the disc supports are arranged in a ring array on the top of the pressure chamber base, and the top end of the push rod is slidably connected to the bottom of the pressure ring.
[0017] This invention provides a testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials. It has the following beneficial effects: 1. This invention uses an existing triaxial shear force apparatus as the main frame and transforms a discarded triaxial pressure chamber into a membrane clamp. The combination of the two achieves new functions, so that the laboratory does not need to spend extra money to purchase a dedicated puncture and burst test machine, directly expanding the testing range of the original triaxial shear force apparatus and effectively saving equipment procurement expenses.
[0018] 2. This invention adds extra small holes between the six holes of the upper and lower fixed discs, increasing the friction between the clamp and the membrane material contact surface, effectively preventing the sample from sliding during the stress process. At the same time, with the use of buffer nuts, the sample can be further tightened, and space is provided for the pressure rod to press the membrane end, avoiding direct damage to the membrane material when the external clamping nut is tightened, thus ensuring the authenticity and accuracy of the test data.
[0019] 3. This invention allows for quick switching between puncture and burst test modes by replacing the upper and lower fixed discs and the corresponding top rods. It is easy to operate. The device is equipped with a conversion locking rod and a pressure sensor. The conversion locking rod can physically lock the drive connection to prevent the equipment from going out of control. The sensor, together with the computer and data acquisition instrument, can sense the sudden drop in pressure at the moment the membrane ruptures and automatically control the motor to stop, realizing automated monitoring and accurate data acquisition of the test process. Attached Figure Description
[0020] Figure 1 This is a perspective view of the present invention; Figure 2This is a schematic diagram of the disc support structure of the present invention; Figure 3 This is a schematic diagram of the pressure chamber base structure of the present invention; Figure 4 This is a schematic diagram of the pressure circular top seat structure of the present invention; Figure 5 This is a schematic diagram of the pressure chamber top seat structure of the present invention; Figure 6 This is a schematic diagram of the piercing head structure of the present invention; Figure 7 This is a schematic diagram of the rupture head structure of the present invention; Figure 8 This is a schematic diagram of the conversion locking lever structure of the present invention; Figure 9 This is a schematic diagram of the pressure ring structure of the present invention.
[0021] The components include: 1. Computer; 2. Data acquisition instrument; 3. Upper top seat; 4. Pressure ring; 5. Pressure gauge; 6. Pressure needle; 7. Fixed disc support rod; 8. Upper fixed disc; 9. Lower fixed disc; 10. Lead screw; 11. Pressure chamber base; 12. Groove; 13. Top rod; 14. Pressure chamber top seat; 15. Compression nut; 16. Buffer nut; 17. Disc support cylinder; 18. Pressure circular top seat; 19. Coarse adjustment calibration compass; 20. Conversion locking rod; 21. Fine adjustment calibration compass; 22. Drive motor; 23. Sensor; 24. Base speed distribution box; 25. Coarse adjustment pointing; 26. Fine adjustment pointing; 27. Piercing head; 28. Top piercing head; 29. Support seat. Detailed Implementation
[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0023] See attached document Figure 1 - Appendix Figure 9 This invention provides a test instrument based on a triaxial shear force meter for testing the puncture and burst strength of membrane materials, including a computer 1, a data acquisition instrument 2, and a support base 29. Two lead screws 10 are fixedly connected to the top of the support base 29, and an upper top seat 3 is fixedly connected to the top of the lead screws 10. A pressure detection component is provided at the bottom of the upper top seat 3. A pressure circular top seat 18 is slidably connected to the top of the support base 29. A pressure chamber base 11 is provided at the top of the pressure circular top seat 18, and a groove 12 is provided at the bottom of the pressure chamber base 11. Multiple disc supports 17 are fixedly connected to the top of the pressure chamber base 11. A fixing component is provided on the top of the disc supports 17. A fixing disc support rod 7 is fixedly connected to the top of each disc support 17. A pressure chamber top seat 14 is provided on the outer wall of the fixing disc support rod 7. A top rod 13 is fixedly connected to the top of the pressure chamber top seat 14. A force application component is provided at the bottom of the pressure chamber top seat 14. A buffer component is provided on the outer wall of each fixing disc support rod 7. An adjustment component is provided on the top of the support seat 29. A drive component is provided inside the support seat 29. The computer 1 is electrically connected to the data acquisition instrument 2. One end of the data acquisition instrument 2 is electrically connected to the output end of the pressure gauge 5, and the other end of the data acquisition instrument 2 is electrically connected to the output end of the sensor 23. The pressure detection assembly includes a pressure ring 4, a pressure gauge 5, and a pressure needle 6. The top of the pressure ring 4 is fixedly connected to the outer wall of the pressure gauge 5, the top of the pressure gauge 5 is fixedly connected to the bottom of the upper seat 3, and the top of the pressure needle 6 is fixedly connected to the bottom of the pressure gauge 5. The adjustment assembly includes a lifting mechanism and a changing mechanism. The lifting mechanism includes a coarse adjustment calibration compass 19 and a fine adjustment calibration compass 21. The coarse adjustment calibration compass 19 is rotatably connected to one side of the top of the support base 29, and the fine adjustment calibration compass 21 is rotatably connected to one side of the top of the support base 29 adjacent to the coarse adjustment calibration compass 19. The changing mechanism includes a conversion locking lever 20. One end of the conversion locking lever 20 is rotatably connected to the top of the support base 29 on the same side as the fine adjustment calibration compass 21. A coarse adjustment indicator 25 is provided on one side of the conversion locking lever 20, and a fine adjustment indicator 26 is provided on the opposite side of the coarse adjustment indicator 25. The drive assembly includes a drive motor 22, a sensor 23, and a base speed distribution box 24. The outer wall of the drive motor 22 is fixedly connected to the inside of the base speed distribution box 24. The output end of the drive motor 22 is connected to the bottom end of the pressure circular top seat 18. The outer wall of the sensor 23 is fixedly connected to the inside of the base speed distribution box 24. The top of the base speed distribution box 24 is fixedly connected to the inner wall of the support seat 29. The disc support cylinders 17 are arranged in a ring array on the top of the pressure chamber base 11. The top end of the top rod 13 is slidably connected to the bottom of the pressure ring 4.
[0024] Specifically, when using this membrane strength testing instrument based on a triaxial shear force meter, a modular, specially designed clamping assembly replaces the traditional pressure chamber structure. During the test preparation phase, the operator sequentially places six disc supports 17 onto the fixed disc support rod 7, constructing a stable underlying structure supporting the lower fixed disc 9. The membrane material to be tested is then laid flat and tightly clamped between the lower fixed disc 9 and the upper fixed disc 8. During the test loading phase, the assembled clamping device, with its bottom groove 12, fits into the lower pressure circular top seat 18. Then, through a linkage operation, the locking lever 20 and the coarse adjustment compass 19 are quickly adjusted to the correct height until the tip of the piercing head 28 or the tip of the puncturing head 27 just touches the upper pressure ring 4. The fine adjustment compass 21 then precisely zeros the pressure gauge 5. With the locking lever... Pressing the locking internal pressure connection 20 triggers the computer 1 to activate the base speed distribution box 24 and drive motor 22, driving the pressure circular top seat 18 and the entire clamping assembly to move upward at a constant speed. This forces the top rod 13, which is blocked by the upper fixed pressure ring 4, to move downward relative to the ground, thereby continuously and stably loading the membrane material inside the disc with a puncture or burst load. During the critical data acquisition and control phase, the sensor 23 integrated below the pressure circular top seat 18 monitors the axial pressure fluctuations around the clock. Once the membrane sample reaches its ultimate strength and ruptures, the sensor 23 can sensitively capture the instantaneous pressure drop signal and transmit it synchronously to the data acquisition instrument 2. After receiving the feedback, the computer 1 quickly issues a stop command to block the drive motor 22 from running, which not only prevents the equipment from overloading and going out of control, but also ensures the accurate recording of test data and the safety of the operation process.
[0025] See attached document Figure 2 - Appendix Figure 4 The fixing components include an upper fixing disc 8 and a lower fixing disc 9. The inner wall of the upper fixing disc 8 is slidably connected to the outer wall of the fixing disc support rod 7, and the inner wall of the lower fixing disc 9 is slidably connected to the outer wall of the fixing disc support rod 7. The bottom of the upper fixing disc 8 is slidably connected to the top of the lower fixing disc 9. Multiple fine holes are provided at the bottom of the upper fixing disc 8 and the top of the lower fixing disc 9. Each buffer component includes a clamping nut 15 and a buffer nut 16. The inner wall of the clamping nut 15 is threadedly connected to the top of the fixing disc support rod 7, and the inner wall of the buffer nut 16 is threadedly connected to the outer side of the fixing disc support rod 7. The buffer nut 16 is located at the bottom of the pressure chamber top seat 14.
[0026] Specifically, additional micro-holes are arranged on the contact plane of the upper fixed disc 8 and the lower fixed disc 9. This physical structure enhances the mechanical interlocking force and the interface friction coefficient between the clamp and the flexible membrane. At the same time, the buffer nut 16 is introduced as a key protective medium. Before the external clamping nut 15 forcefully locks the pressure chamber top seat 14, a necessary buffer stroke and accommodation space are reserved in advance. This not only avoids physical pre-damage to the sample caused by rigid closing compression during the installation stage, but also fundamentally eliminates the phenomenon of sample edge slippage during the high-load bursting process, thereby ensuring the authenticity and stability of the test data.
[0027] See attached document Figure 5 - Appendix Figure 7 The force application components include a puncture head 27 and a top puncture head 28. A universal interface is provided at the bottom of the pressure chamber top seat 14. The universal interface can be connected to the puncture head 27 or the top puncture head 28 according to different test conditions.
[0028] Specifically, operators only need to adapt and replace the upper fixed disc 8, the lower fixed disc 9, and the key loading components, the piercing head 28 or the puncturing head 27, to achieve seamless switching and functional compatibility between two completely different mechanical test modes, piercing performance testing and puncturing performance testing, under the premise of sharing the same basic equipment platform.
[0029] Working Principle: In the process of using a triaxial shear force apparatus to test the bursting and puncture strength of membrane materials, this instrument utilizes the main structure of the triaxial shear force apparatus as a loading platform. A specially designed clamping assembly replaces the original pressure chamber. Before the test, six disc supports 17 are fitted onto the fixed disc support rod 7 to support the lower fixed disc 9. The membrane sample is placed between the lower fixed disc 9 and the upper fixed disc 8. Additional fine holes are provided between the two discs to increase friction, and a buffer nut 16 provides buffer space before the pressure chamber top seat 14 is locked by the clamping nut 15, preventing damage to the sample during installation and slippage during the test. By changing the upper fixed disc 8, lower fixed disc 9, and bursting head 28 or puncture head 27 of different specifications, the bursting and puncture test modes can be flexibly switched on the same equipment.
[0030] During the loading test, the assembled clamping device is inserted into the lower pressure circular top seat 18 through the groove 12. The height is adjusted by operating the conversion locking lever 20 in conjunction with the coarse adjustment compass 19, so that the upper end of the puncture head 28 or the piercing head 27 just contacts the upper pressure ring 4. Then, the pressure gauge 5 is zeroed with the fine adjustment compass 21. After pressing the conversion locking lever 20 to lock the internal pressure connection, the computer 1 controls the base speed distribution box 24 and the drive motor 22 to work, driving the pressure circular top seat 18 and the entire clamping device to move upward at a constant speed. Since the upper end of the top rod 13 is blocked by the fixed pressure ring 4, the puncture head 28 or the piercing head 27 at the lower end of the top rod 13 will move downward relative to it, thereby applying a puncture or burst load to the membrane material clamped in the disc.
[0031] In terms of data acquisition and control, the system uses a sensor 23 located below the pressure circular top seat 18 to monitor the axial pressure change in real time. When the membrane sample reaches its ultimate strength and ruptures, the axial pressure will drop sharply. After the sensor 23 captures the signal, it immediately transmits it to the data acquisition instrument 2. After receiving the feedback signal, the computer 1 immediately issues a command to stop the operation of the drive motor 22 to prevent the equipment from overloaded or out of control, thus ensuring the accurate recording of test data and the safety of the operation process.
Claims
1. A testing instrument based on a triaxial shear force analyzer for testing the bursting and puncture strength of membrane materials, characterized in that, Includes a computer (1), a data acquisition instrument (2) and a support base (29). The support base (29) has two lead screws (10) fixedly connected to its top. The lead screws (10) have an upper top seat (3) fixedly connected to their top ends. The upper top seat (3) has a pressure detection component at its bottom. The support base (29) has a pressure circular top seat (18) slidably connected to its top. The pressure circular top seat (18) has a pressure chamber base (11) on its top. The pressure chamber base (11) has a groove (12) at its bottom. The pressure chamber base (11) is fixedly connected to a plurality of disc support cylinders (17) at the top. The disc support cylinders (17) are provided with a fixing component at the top. Each disc support cylinder (17) is fixedly connected to a fixed disc support rod (7) at the top. The outer wall of the fixed disc support rod (7) is provided with a pressure chamber top seat (14). The top of the pressure chamber top seat (14) is fixedly connected with a top rod (13). The bottom of the pressure chamber top seat (14) is provided with a force application component. The outer wall of each fixed disc support rod (7) is provided with a buffer component. The top of the support seat (29) is provided with an adjustment component. The inside of the support seat (29) is provided with a drive component.
2. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The pressure detection assembly includes a pressure ring (4), a pressure gauge (5) and a pressure needle (6). The top of the pressure ring (4) is fixedly connected to the outer wall of the pressure gauge (5), the top of the pressure gauge (5) is fixedly connected to the bottom of the upper seat (3), and the top of the pressure needle (6) is fixedly connected to the bottom of the pressure gauge (5).
3. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The fixing assembly includes an upper fixing disc (8) and a lower fixing disc (9). The inner wall of the upper fixing disc (8) is slidably connected to the outer wall of the fixing disc support rod (7). The inner wall of the lower fixing disc (9) is slidably connected to the outer wall of the fixing disc support rod (7). The bottom of the upper fixing disc (8) and the top of the lower fixing disc (9) are fitted together. Both the bottom of the upper fixing disc (8) and the top of the lower fixing disc (9) are provided with multiple fine holes.
4. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The force-applying component includes a puncture head (27) and a top puncture head (28). The bottom of the pressure chamber top seat (14) is provided with a universal interface, which can be connected to the puncture head (27) or the top puncture head (28) according to different test conditions.
5. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, Each of the aforementioned buffer components includes a clamping nut (15) and a buffer nut (16), the inner wall of which is threaded to the top of the fixed disc support rod (7), and the inner wall of which is threaded to the outside of the fixed disc support rod (7), and the buffer nut (16) is located at the bottom of the pressure chamber top seat (14).
6. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The adjustment assembly includes a lifting mechanism and a changing mechanism. The lifting mechanism includes a coarse adjustment calibration compass (19) and a fine adjustment calibration compass (21). The coarse adjustment calibration compass (19) is rotatably connected to one side of the top of the support base (29), and the fine adjustment calibration compass (21) is rotatably connected to one side of the top of the support base (29) adjacent to the coarse adjustment calibration compass (19).
7. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 6, characterized in that, The changing mechanism includes a conversion locking lever (20), one end of which is rotatably connected to the top of the support base (29) on the same side as the fine adjustment calibration compass (21). A coarse adjustment indicator (25) is provided on one side of the conversion locking lever (20), and a fine adjustment indicator (26) is provided on the opposite side of the coarse adjustment indicator (25).
8. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The drive assembly includes a drive motor (22), a sensor (23), and a base speed distribution box (24). The outer wall of the drive motor (22) is fixedly connected to the inside of the base speed distribution box (24). The output end of the drive motor (22) is connected to the bottom end of the pressure circular top seat (18). The outer wall of the sensor (23) is fixedly connected to the inside of the base speed distribution box (24). The top of the base speed distribution box (24) is fixedly connected to the inner wall of the support seat (29).
9. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The computer (1) is electrically connected to the data acquisition instrument (2). One end of the data acquisition instrument (2) is electrically connected to the output end of the pressure gauge (5), and the other end of the data acquisition instrument (2) is electrically connected to the output end of the sensor (23).
10. The testing instrument based on a triaxial shear force analyzer for testing the puncture and burst strength of membrane materials according to claim 1, characterized in that, The disc support cylinders (17) are arranged in a ring array on the top of the pressure chamber base (11), and the top end of the top rod (13) is slidably connected to the bottom of the pressure ring (4).