Novel bolt lug residual strength testing device and method

Abstract

The invention belongs to the technical field of structural test mechanics, and particularly relates to a novel bolt lug residual strength test device and method. Comprising a screw rod, a clamping platform, a clamping flat plate, a check block and a connecting clamping block. The screw rod is arranged below the clamping platform and above the connecting clamping block, the clamping platform is provided with the two clamping flat plates, the two clamping flat plates are fixed in the connecting clamping block, the clamping flat plates and the clamping platform are both provided with experiment screw holes, the clamping platform is further provided with a check block mounting hole, and the check block mounting hole is connected with the clamping platform. The check block is installed on the clamping platform through a bolt. The device is simple and reliable in structure and convenient to use, the loading condition of a test piece is consistent with the loading condition of the test piece in an original component, and the device is universal for various bolt lug strength tests.

Description

Technical Field

[0001] The invention belongs to the technical field of structural test mechanics, and in particular relates to a novel bolt ear residual strength test device and method. Background Art

[0002] The lug connection is a widely used connection structure on aircraft, usually used in conjunction with bolts to achieve a firm connection between parts. However, due to the stress concentration effect around the lug bolt holes, fatigue cracks or even fractures are prone to occur near the bolt holes during long-term use of the aircraft, especially under frequent takeoffs, landings and vibrations during flight, which not only affects the overall integrity and safety of the structure, but may also lead to serious flight accidents. Therefore, the strength study of bolted lugs, especially the evaluation of their residual strength, has become an important research topic in the field of structural mechanics.

[0003] In actual engineering applications, the loading direction of many bolt ears is not perpendicular to the bolt hole, which brings challenges to the residual strength test. Traditional test methods can only apply loads in the direction perpendicular to the bolt hole, which cannot truly reflect the stress conditions under actual working conditions. In addition, different types of bolts (such as explosive bolts, auxiliary bolts and ordinary bolts) require different clamping devices in the test, which further increases the complexity and cost of the test. Conventional residual strength test schemes can usually only test specific types of bolt ears, lack versatility and flexibility, and are difficult to meet diverse test needs. Summary of the invention

[0004] The technical problem to be solved by the present invention is that in the above-mentioned prior art, the traditional test method can often only apply load in the direction perpendicular to the bolt hole, which cannot truly reflect the stress conditions under actual working conditions.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A novel bolt ear residual strength test device comprises a screw rod, a clamping platform, a clamping plate, a block and a connecting clamping block; the screw rod is arranged below the clamping platform and above the connecting clamping block, two clamping plates are arranged on the clamping platform, the two clamping plates are fixed inside the connecting clamping block, the clamping plate and the clamping platform are both provided with experimental screw holes, the clamping platform is also provided with a block mounting hole, and the block is mounted on the clamping platform by bolts.

[0006] By adopting the above technical scheme, the device can be applied to the residual strength test of various bolt ears by replacing different blocks, and has high versatility and flexibility. The design of the oblique pentagonal clamping platform enables the vertical load provided by the testing machine to be converted into the oblique load required by the test piece, which more realistically simulates the stress conditions under actual working conditions. The design of the clamping platform and the clamping plate takes into account the convenience of actual operation. For example, the hollow design facilitates the installation and inspection of bolts, and the strain gauge wires can be led out from the hollow part to avoid data interference. The design of the three-step clamping plate can prevent excessive tightening of the bolts from causing additional compression to the test piece, ensuring the stability of the test piece during loading. Through precise clamping and loading methods, the device can provide reliable test data and provide a scientific basis for the strength research of bolt ears. The device is not only suitable for bolt ear tests in the aviation field, but can also be expanded to other engineering fields that require similar tests, and has broad application prospects.

[0007] Furthermore, the front end of the clamping platform is a mounting surface and the rear end is a vertical surface, the angle between the mounting surface and the horizontal plane is 0°-45°, the mounting surface and the vertical surface are hollowed out, and there are 6 block mounting holes on each side of the mounting surface.

[0008] By adopting the above technical solution, the vertical load provided by the testing machine can be converted into the oblique load required by the test piece by adjusting the angle of the mounting surface. This can not only simulate various stress conditions under actual working conditions, but also ensure the accuracy and reliability of the test results. For bolt lugs with different force directions, accurate loading tests can be carried out by adjusting the angle of the mounting surface. The hollow design between the mounting surface and the vertical surface provides sufficient space for easy installation and inspection of the connecting bolts. At the same time, the strain gauge and its wires can be led out from the hollow part, avoiding the problem of inaccurate data caused by the wire being pressed, simplifying the test operation process, and there are 6 block mounting holes on the left and right sides of the mounting surface: This design allows the installation of different types of blocks (such as arch bridge cover and rectangular flat block) to meet the test requirements of different types of bolt lugs. This greatly improves the versatility and flexibility of the device and reduces the frequency and cost of replacing the test device. The combined design of the front mounting surface and the rear vertical surface: This structural design not only ensures the stability of the device, but also provides good support during the test to prevent the displacement or deformation of the test piece during loading. The design of the vertical surface helps to maintain the overall rigidity of the device and ensure stability during the test. By adjusting the angle of the mounting surface, the force direction of the test piece can be accurately controlled to ensure the accuracy and consistency of the test data. This is very important for scientific research and engineering applications.

[0009] Furthermore, the clamping plate includes a clamping plate 1 and a clamping plate 2, and six rows of bolt holes are arranged on the surfaces of the clamping plate 1 and the clamping plate 2. Corresponding pin shaft holes are arranged on the tops of the clamping plate 1 and the clamping plate 2. The clamping plate 1 is a rectangular parallelepiped, and the thickness of the clamping plate 2 increases by 10mm-20mm every two rows of bolt holes, forming a stepped shape.

[0010] By adopting the above technical solution, the surfaces of the clamping plate 1 and the clamping plate 2 are both provided with six rows of bolt holes, which can adapt to test pieces of different sizes and shapes. This makes the device highly versatile and can meet the test requirements of various bolt lugs. The thickness of the clamping plate 2 increases by 10mm-20mm every two rows of bolt holes, and is designed in a stepped manner. This design can prevent excessive compression of the test piece when tightening the bolts, and ensure that the deformation and stress state of the test piece during the loading process are consistent with the actual working conditions. The stepped design of the clamping plate 2 can better adapt to the shape of the test piece and provide a more stable clamping effect. Especially during the loading process, this design can reduce the displacement and shaking of the test piece and ensure the accuracy of the test data. The tops of the clamping plates 1 and 2 are provided with corresponding pin holes, and the clamping plates are connected to the chuck on the testing machine through the pins to ensure the stable transmission of the load. This design simplifies the installation and disassembly process and improves the efficiency of the test. The test piece is firmly fixed on the clamping plate through six rows of bolt holes to ensure the uniform distribution of the load on the test piece. This helps to avoid local stress concentration and ensure the reliability of the test results. The stepped design of the clamping plate 2 can better match the shape of the test piece and reduce the error caused by improper clamping. This helps to improve the accuracy and repeatability of the test.

[0011] Furthermore, the block includes an arch bridge cover block and a flat block. The arch bridge cover block has a row of three bolt holes on both sides, corresponding to the position of the block mounting holes on the outside of the clamping platform, and a test piece connection hole is arranged in the middle of the arch bridge cover block; the flat block has a row of three bolt holes on both sides, corresponding to the position of the block mounting holes on the inside of the clamping platform, and a test piece connection hole is also arranged in the middle of the flat block.

[0012] By adopting the above technical solution, the arch bridge design can better adapt to the shape of the explosive bolt ear piece, ensure the stability and reliability of the test piece during the loading process, and is suitable for auxiliary bolt and ordinary bolt ear piece testing. Its flat plate design is simple and suitable for the test needs of various common bolt ears. The bolt holes of the arch bridge cover block and the flat plate block correspond to the block mounting holes of the clamping platform, ensuring that the block can be firmly fixed on the clamping platform to prevent loosening during the test. The test piece connection hole in the middle can accurately fix the test piece on the block to ensure the accurate positioning of the test piece during loading. The arch bridge cover block and the flat plate block are fixed to the clamping platform by bolts. The block can be quickly replaced according to the test requirements, which improves the flexibility and efficiency of the test. The bolt connection method makes the installation and disassembly of the block very convenient and simplifies the test operation process. The arch bridge type design can provide better support, reduce the deformation and displacement of the test piece during loading, and ensure the accuracy of the test data. The flat plate design is simple and reliable, and can provide a stable clamping effect to ensure the stability of the test piece during loading. The design of the test piece connection hole ensures the accurate positioning of the test piece, avoids test errors caused by inaccurate positioning, and improves the reliability of the test data.

[0013] The present invention also includes a novel bolt ear residual strength test method, which uses the novel bolt ear residual strength test device to test the bolt ear residual strength, the ear portion of the test piece is tightly attached to the mounting surface of the clamping platform, so that the non-ear portion of the test piece is perpendicular to the ground, and the wire corresponding to the strain gauge on the back of the test piece extends from the hollow portion of the clamping platform and is connected to the strain box; the arch bridge cover block or the flat plate block is connected to the ear of the test piece, so that the bolt hole of the arch bridge cover block or the flat plate block corresponds to the position of the block mounting hole of the mounting surface, the arch bridge cover block or the flat plate block is connected to the clamping platform by bolts, the test piece connection hole on the arch bridge cover block or the flat plate block corresponds to the position of the ear bolt hole, and the ear is connected to the arch bridge cover block or the flat plate block (52) by bolts using the hollow portion of the clamping platform.

[0014] By adopting the above technical scheme, the angle between the installation surface of the clamping platform and the horizontal plane is 0°-45°, which can accurately simulate the stress conditions under actual working conditions and ensure the accuracy of the test results. The non-ear part of the test piece is perpendicular to the ground, ensuring that the force direction of the test piece during loading is consistent with the actual working conditions. The hollow design of the clamping platform allows the wires of the strain gauge to be smoothly led out, avoiding the problem of inaccurate data caused by the wires being pressed. The block is connected to the clamping platform by bolts, which is easy to operate and quick to install and disassemble, thereby improving the test efficiency. The wires of the strain gauge on the back of the test piece are led out from the hollow part and connected to the strain box to ensure accurate collection of strain data. The bolt hole of the block corresponds to the position of the block mounting hole of the clamping platform, ensuring the precise fixation of the test piece and avoiding test errors caused by improper fixation. The arch bridge cover block and the flat block are respectively suitable for different types of bolt ear tests, and have high adaptability and versatility.

[0015] Furthermore, the clamping plate 1 and the clamping plate 2 are used to cover the non-ear plate parts of the test piece from the front and back sides, the clamping plate 1 is tightly attached to the side of the vertical surface of the test piece close to the clamping platform, and the clamping plate 2 is tightly attached to the side of the installation surface of the test piece close to the clamping platform, the experimental screw holes on the surfaces of the clamping plate 1 and the clamping plate 2 are aligned with the bolt holes on the surface of the test piece, and the clamping plate and the test piece are connected together using bolts.

[0016] By adopting the above technical solution, the experimental screw holes of the clamping plate 1 and the clamping plate 2 are aligned with the bolt holes on the surface of the test piece, and bolts are used to connect them, so that the test piece can be accurately fixed at multiple points, avoiding displacement and shaking of the test piece during the test. The clamping plate 1 and the clamping plate 2 cover the non-ear plate parts of the test piece from the front and back sides to ensure the stability of the test piece during the loading process and prevent local uneven force. The clamping plate 1 is tightly attached to the vertical side of the test piece close to the clamping platform to ensure that the force direction of the test piece during the loading process is consistent with the actual working condition. It is tightly attached to the mounting surface of the test piece close to the clamping platform to ensure that the force direction of the test piece during loading is consistent with the actual working condition. Especially when the mounting surface angle is adjusted, the force conditions in different directions can be simulated. The clamping plate is connected to the test piece by bolts. The operation is simple, and the installation and disassembly are quick, which improves the test efficiency. The experimental screw holes on the surface of clamping plate 1 and clamping plate 2 are aligned with the bolt holes on the surface of the test piece to ensure the accuracy and reliability of the connection. The design of clamping plate 1 and clamping plate 2 provides good support to ensure the stability of the test piece during loading.

[0017] Furthermore, the clamping platform is installed on the lower chuck of the test bench through the screw rod, and the upper end of the clamping plate is connected to the upper chuck of the test machine.

[0018] By adopting the above technical solution, the screw mounts the clamping platform on the lower chuck of the test bench, ensuring the stable transmission of the load. The screw connection method can provide a reliable mechanical connection to ensure the continuity and stability of the load during the test. The upper end of the clamping plate is connected to the upper chuck of the test machine through the pin hole, ensuring the continuity and stability of the load from the upper part of the test machine to the test piece. The screw connection and the pin hole design make the installation and disassembly of the clamping platform and the clamping plate very convenient, simplifying the test operation process and improving the test efficiency. The screw connection method allows fine-tuning during the installation process to ensure the precise alignment of the clamping platform and improve the accuracy of the test. The multi-point fixing design of the screw and the pin hole can effectively disperse and bear the load during the test, reduce the wear and damage of the clamping platform and the clamping plate, and extend the service life of the device. The vertical surface and mounting surface design of the clamping platform provide good support to ensure the stability of the test piece during loading.

[0019] Furthermore, a strain gauge is pasted on the surface of the test piece and electrically connected to the test bench. It is first loaded to 30% of the failure load at a loading rate not higher than 2 mm / min and then unloaded to 0%. Each test piece is pre-tested twice and then the failure load is increased from 0% of the failure load at a loading rate not higher than 2 mm / min until the test piece is destroyed.

[0020] By adopting the above technical solution, first load to 30% of the failure load at a loading rate not higher than 2mm / min, and then unload to 0%, and pre-test each test piece twice. This step can ensure that there are no problems with the adhesion and electrical connection of the strain gauge, avoid data errors caused by the strain gauge falling off or poor connection, and pre-test can eliminate the elastic deformation and other potential errors of the test piece in the initial stage, ensure the accuracy of the formal test, and check the operating status of the test equipment to ensure the normal operation of the equipment in the formal test. Load at a loading rate not higher than 2mm / min, slow loading can avoid impact and transient stress caused by excessive loading, ensure uniform force on the test piece during loading, slow loading can more accurately control the loading rate, ensure the stability and reliability of the test data, and gradually increase from 0% of the failure load to the failure load. During the gradual loading process, the data changes of the strain gauge can be observed in real time, and the abnormal situation of the test piece can be discovered in time. Gradual loading can avoid sudden damage to the test piece caused by sudden loading, and ensure the safety of test personnel and equipment.

[0021] The present invention has the following beneficial effects: 1. The present invention can accurately simulate the stress conditions under actual working conditions through the mounting surface of the clamping platform. The ear part of the test piece is in close contact with the mounting surface of the clamping platform, and the non-ear part is perpendicular to the ground, which ensures that the stress direction of the test piece during loading is consistent with the actual working conditions, making the test results more accurate and providing a reliable basis for the strength research of the bolt ear; 2. The present invention adheres strain gauges on the surface of the test piece and electrically connects it to the test bench, so that the strain changes of the test piece during the loading process can be monitored in real time. The pre-test step (loading to 30% of the failure load at a loading rate not higher than 2mm / min, and then unloading to 0%, and each test piece is pre-tested twice) can eliminate the initial error, check the reliability of the strain gauges and connections, and ensure the accuracy of the formal test. Gradual loading (from 0% failure load to failure load until the test piece is destroyed) can observe the strain changes and ensure the stability and reliability of the test data; 3. The present invention installs the clamping platform on the chuck below the test bench through a screw rod, and the upper end of the clamping plate is connected to the chuck on the testing machine through a pin hole, which ensures the stable transmission of the load. The clamping plate 1 and the clamping plate 2 cover the non-ear parts of the test piece from the front and back sides. The multi-point fixing design can effectively disperse and withstand the load during the test, reduce the wear and damage of the device, and extend the service life. The bolt connection method makes installation and disassembly convenient, simplifies the test operation process, and improves the test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a front view of the present invention; Figure 3 It is a left side view of the present invention; Figure 4 It is a rear view of the present invention; Figure 5 It is a structural schematic diagram of the arch bridge cover block of the present invention; Figure 6 It is a structural schematic diagram of the flat plate stopper of the present invention; Figure 7 It is a schematic diagram of the installation of the arch bridge cover block and the explosive bolt ear piece of the present invention; Figure 8 It is a schematic diagram of the installation of the flat plate stopper and the auxiliary bolt ear piece of the present invention; Fig. 9 It is a schematic diagram of the installation of the flat plate stopper and the common bolt ear piece of the present invention.

[0023] Among them, 1-clamping platform; 11-installation surface; 111-block installation hole; 12-vertical surface; 2-clamping plate; 21-clamping plate one; 22-clamping plate two; 3-connecting clamp; 4-experimental screw hole; 5-block; 51-arch bridge cover block; 52-plate block; 53-test piece connection hole; 6-explosive bolt ear; 7-auxiliary bolt ear; 8-ordinary bolt ear; 9-screw. DETAILED DESCRIPTION

[0024] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0025] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper part", "lower part" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second" and the like do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the scope of protection of the present invention.

[0026] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, a novel bolt ear residual strength test device is provided, wherein the screw is arranged below the clamping platform 1 and above the connecting clamp block 3, for transmitting the tensile load provided by the testing machine. The clamping platform 1 is the core part of the device, and its front end is a mounting surface 11, and the rear end is a vertical surface 12. The angle between the mounting surface 11 and the horizontal plane is 45°, and there is a hollow setting between the mounting surface 11 and the vertical surface 12. There are 6 block mounting holes 111 on the left and right sides of the mounting surface 11, respectively. The clamping plate 2 includes a clamping plate 1 21 and a clamping plate 2 22, which are fixed inside the connecting clamp block 3. Six rows of bolt holes are arranged on the surfaces of the clamping plate 1 21 and the clamping plate 2 22, and corresponding pin shaft holes are arranged on the top. The clamping plate 1 21 is a rectangular parallelepiped, and the thickness of the bolt holes of the clamping plate 2 22 increases by 10mm-20mm every two rows, forming a stepped shape. The block 5 includes an arch bridge cover block 51 and a flat block 52. The arch bridge cover block 51 has three bolt holes on both sides, which correspond to the position of the block mounting hole 111 on the outside of the clamping platform 1, and a test piece connecting hole 53 is arranged in the middle. The flat block 52 has three bolt holes on both sides, which correspond to the position of the block mounting hole 111 on the inside of the clamping platform 1, and a test piece connecting hole 53 is also arranged in the middle. The connecting clamp 3 is located above the clamping plate 2; The arch bridge cover block 51 is in the shape of a cover with closed two ends and open front and back, which can better adapt to the shape of the ear piece of the explosive bolt. There is a row of three bolt holes on the left and right sides of the arch bridge cover block 51, and these bolt holes correspond to the position of the block mounting holes 111 on the outside of the clamping platform 1, which are used to fix the arch bridge cover block 51 on the clamping platform 1. A test piece connecting hole 53 is provided in the middle of the arch bridge cover block 51, which is used to connect the ear piece part of the test piece with the block. The arch bridge cover block 51 is aligned with the block mounting hole 111 of the clamping platform 1 through the bolt holes on both sides, and the arch bridge cover block is fixed to the clamping platform 1 with bolts, and the ear piece part of the test piece is aligned with the middle test piece connecting hole 53 of the arch bridge cover block 51, and the ear piece is installed between the arch bridge cover block 51 and the mounting surface 11 with bolts.

[0027] The flat block 52 has a row of three bolt holes on each side, corresponding to the block mounting holes 111 on the inner side of the clamping platform 1 , a test piece connecting hole 53 is provided in the middle, and an ear piece is installed above the flat block 52 .

[0028] like Figure 7 , Figure 8 and Fig. 9 As shown, a novel bolt ear residual strength test method is provided, wherein the ear portion of the test piece is tightly attached to the mounting surface 11 of the clamping platform 1, ensuring that the non-ear portion of the test piece is perpendicular to the ground, the wire corresponding to the strain gauge on the back of the test piece extends from the hollow portion of the clamping platform (1) and is connected to the strain box, the arch bridge cover plate stopper 51 or the flat plate stopper 52 is connected to the ear portion of the test piece, ensuring that the bolt hole of the stopper corresponds to the position of the stopper mounting hole 111 of the clamping platform 1, the arch bridge cover plate stopper 51 or the flat plate stopper 52 is connected to the clamping platform 1 by bolts, the test piece connection hole 53 on the arch bridge cover plate stopper 51 or the flat plate stopper 52 corresponds to the position of the ear bolt hole, the ear portion is connected to the arch bridge cover plate stopper 51 or the flat plate stopper 52 by bolts using the hollow portion of the clamping platform 1, and the clamping plate 1 21 and the clamping plate 2 22 are connected from the front. The two rear sides cover the non-ear plate parts of the test piece, the clamping plate 1 21 is tightly attached to the vertical surface 12 of the test piece close to the clamping platform 1, and the clamping plate 2 22 is tightly attached to the mounting surface 11 of the test piece close to the clamping platform 1. The experimental screw holes 4 on the surfaces of the clamping plates 1 21 and 22 are aligned with the bolt holes on the surface of the test piece. The clamping plate 2 and the test piece are connected together with bolts. The clamping platform (1) is installed on the lower chuck of the test bench through the screw rod 9. The upper screw rod 9 is connected to the upper chuck of the test machine. The strain gauge is pasted on the surface of the test piece and the strain gauge is electrically connected to the test bench. First, it is loaded to 30% of the failure load at a loading rate of 2 mm / min, and then unloaded to 0%. Each test piece is pre-tested twice, and then the load rate is increased from 0% of the failure load to the failure load at a loading rate of 2 mm / min until the test piece is destroyed. like Figure 7 As shown, the specific implementation steps of the loading test of the explosive bolt ear piece 6 are as follows: Place the ear piece of the test piece tightly against the mounting surface 11 of the clamping platform 1, so that the non-ear piece part of the test piece is perpendicular to the ground. The wire corresponding to the strain gauge on the back of the test piece extends out from the hollowed-out part at the back of the clamping platform 1 and is connected to the strain box of the test bench. Place the arch bridge cover block 51 on the ear piece so that the bolt holes on both sides of the arch bridge cover block 51 correspond to the bolt holes on the outer edge of the mounting surface 11. At this time, the ear piece should be surrounded between the arch bridge cover block 51 and the mounting surface 11. Use six bolts to connect the arch bridge cover block 51 to the clamping platform 1 through the bolt holes on both sides. Make the test piece mounting hole 53 of the arch bridge cover block 51 correspond to the position of the ear piece bolt hole. Use the hollowed-out part at the back of the clamping platform 1 to connect the explosive bolt ear piece 6 with the arch bridge cover block 51. Connect, use the clamping plate 2 to cover the non-ear plate part of the test piece from the front and back sides, the clamping plate 21 is tightly attached to the side of the test piece close to the vertical surface 12 of the clamping platform 1, the clamping plate 22 is tightly attached to the side of the test piece close to the mounting surface 11 of the clamping platform 1, and the thicker side of the clamping plate 22 is on the top, the thinner side is on the bottom, and the flat side faces outward, the clamping plate 21 is in contact with the upper part of the clamping plate 22, and is connected through the connecting clamp 3, eight bolts are used to connect the bolt holes on both sides of the pin hole of the clamping plate 2, the bolt holes on the surface of the clamping plate 2 are aligned one by one with the bolt holes on the surface of the test piece, 24 bolts are used to connect the clamping plate 2 and the test piece through the bolt holes, the device is connected to the test bench through the screw 9, pre-test, load to 30% of the failure load at a loading rate of 2mm / min, and then unload to zero, each test piece is pre-tested twice, and the formal test is loaded from zero load at a loading rate of 2mm / min until the test piece is destroyed. After the test is completed, turn off the power and clean up the laboratory; like Figure 8 and Fig. 9 As shown, the specific implementation steps of the loading test of the auxiliary bolt lug 7 and the ordinary bolt lug 8 are as follows: Place the flat plate stopper 52 on the mounting surface 11 of the clamping platform 1 so that the bolt holes on both sides of the flat plate stopper 52 correspond to the bolt holes on the inner side of the mounting surface 11. Use six bolts to connect the flat plate stopper 52 to the clamping platform 1 through the bolt holes on both sides. Place the ear piece of the test piece on the rectangular flat plate stopper 52. Align the bolt holes of the auxiliary bolt ear piece 7 and the ordinary bolt ear piece 8 with the test piece mounting hole 53 in the middle of the flat plate stopper 52. Use the hollowed-out part at the back of the clamping platform 1 to connect the ear piece to the flat plate stopper 52 with auxiliary bolts. Use the clamping plate 2 1 and the clamping plate 22 cover the non-ear plate part of the test piece from the front and back sides, the clamping plate 21 and the test piece are tightly attached to the vertical surface 12 of the clamping platform 1, the clamping plate 22 and the test piece are tightly attached to the mounting surface of the clamping platform 1, and the thicker side is on the top, the thinner side is on the bottom, and the flat side faces outward, align the four middle rows of bolt holes on the surface of the clamping plate 2 with the bolt holes on the surface of the test piece one by one, use sixteen bolts to connect the clamping plate 2 and the test piece through the bolt holes, connect the device to the test bench through the screw 9, pre-test, load to 30% of the failure load at a loading rate of 2mm / min, and then unload to zero, pre-test each test piece twice, and in the formal test, load from zero load at a loading rate of 2mm / min until the test piece is destroyed.

[0029] The preferred embodiments of the present invention are described in detail above; however, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A new type of bolt lug residual strength test device, characterized in that: The invention comprises a screw rod (9), a clamping platform (1), a clamping plate (2), a stopper (5) and a connecting clamping block (3); the screw rod (9) is arranged below the clamping platform (1) and above the connecting clamping block (3); two clamping plates are arranged on the clamping platform (1); the two clamping plates (2) are fixed inside the connecting clamping block (3); experimental screw holes (4) are arranged on the clamping plate (2) and the clamping platform (1); a stopper mounting hole (111) is also arranged on the clamping platform (1); and the stopper is mounted on the clamping platform (1) by bolts.

2. The novel bolt lug residual strength test device according to claim 1 is characterized in that: The front end of the clamping platform (1) is a mounting surface (11) and the rear end is a vertical surface (12); the angle between the mounting surface (11) and the horizontal plane is 0°-45°; there is a hollow space between the mounting surface (11) and the vertical surface (12); and there are six stopper mounting holes (111) on each of the left and right sides of the mounting surface (11).

3. The novel bolt lug residual strength test device according to claim 1 is characterized in that: The clamping plate (2) comprises a clamping plate 1 (21) and a clamping plate 2 (22), the surfaces of the clamping plate 1 (21) and the clamping plate 2 (22) are both provided with six rows of bolt holes, the tops of the clamping plate 1 (21) and the clamping plate 2 (22) are provided with corresponding pin holes, the clamping plate 1 (21) is a rectangular parallelepiped, and the thickness of the clamping plate 2 (22) increases by 10 mm to 20 mm every two rows of bolt holes, forming a stepped shape.

4. The novel bolt lug residual strength test device according to claim 1 is characterized in that: The stopper (5) comprises an arch bridge cover stopper (51) and a flat stopper (52); the arch bridge cover stopper (51) has a row of three bolt holes on both sides thereof, corresponding to the position of the stopper mounting hole (111) on the outside of the clamping platform (1); a test piece connection hole (53) is arranged in the middle of the arch bridge cover stopper (51); the flat stopper (52) has a row of three bolt holes on both sides thereof, corresponding to the position of the stopper mounting hole (111) on the inside of the clamping platform (1); a test piece connection hole (53) is also arranged in the middle of the flat stopper (52).

5. A novel bolt lug residual strength test method, comprising the novel bolt lug residual strength test device according to any one of claims 1 to 4, characterized in that: The ear piece of the test piece is tightly attached to the mounting surface (11) of the clamping platform (1), so that the non-ear piece part of the test piece is perpendicular to the ground, and the wire corresponding to the strain gauge on the back of the test piece extends from the hollow part of the clamping platform (1) and is connected to the strain box; the arch bridge cover plate stopper (51) or the flat plate stopper (52) is connected to the ear piece of the test piece, so that the bolt hole of the arch bridge cover plate stopper (51) or the flat plate stopper (52) is aligned with the bolt hole of the mounting surface (11). The position of the block mounting hole (111) corresponds to that of the arch bridge cover block (51) or the flat block (52) and the clamping platform (1) by bolts, the test piece connection hole (53) on the arch bridge cover block (51) or the flat block (52) corresponds to that of the ear bolt hole, and the ear is connected to the arch bridge cover block (51) or the flat block (52) by bolts using the hollowed-out portion of the clamping platform (1).

6. The novel bolt lug residual strength test method according to claim 5 is characterized in that: The clamping plate 1 (21) and the clamping plate 2 (22) are used to cover the non-ear plate parts of the test piece from the front and back sides. The clamping plate 1 (21) is tightly attached to the side of the test piece close to the vertical surface (12) of the clamping platform (1), and the clamping plate 2 (22) is tightly attached to the side of the test piece close to the mounting surface (11) of the clamping platform (1). The experimental screw holes (4) on the surfaces of the clamping plate 1 (21) and the clamping plate 2 (22) are aligned with the bolt holes on the surface of the test piece, and the clamping plate and the test piece are connected together using bolts.

7. The novel bolt lug residual strength test method according to claim 5 is characterized in that: The clamping platform (1) is mounted on the lower chuck of the test bench via the screw rod (9), and the upper end of the clamping plate is connected to the upper chuck of the test machine.

8. The novel bolt lug residual strength test method according to claim 5 is characterized in that: A strain gauge is pasted on the surface of the test piece and electrically connected to the test bench. First, it is loaded to 30% of the failure load at a loading rate not higher than 2mm / min, and then unloaded to 0%. Each test piece is pre-tested twice, and then the failure load is increased from 0% of the failure load at a loading rate not higher than 2mm / min until the test piece is destroyed.

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