A device and method for resonant fatigue testing of a cable

Abstract

The application discloses a kind of cable resonance fatigue test device and method, it is related to cable fatigue performance detection technical field, device includes: first counterforce seat and second counterforce seat of interval opposite arrangement, tool cable, actuator, inertial container, first counterforce seat and second counterforce seat between being provided with slidable connecting piece, one end of test cable is anchored to first counterforce seat, the other end of test cable is anchored to connecting piece, one end of tool cable is anchored to connecting piece, the other end of tool cable passes through second counterforce seat and is connected with the pre-tightening assembly for applying pre-tension to tool cable, tool cable and test cable form opposite tension, actuator drives connecting piece reciprocating sliding between first counterforce seat and second counterforce seat, one end of inertial container is connected to connecting piece, inertial force generated by inertial container and the elastic force generated by repeatedly stretching test cable and tool cable are offset.This application reduces the overall cost of equipment and the demand of equipment to installation space.

Description

Technical Field

[0001] This invention relates to the field of cable fatigue performance testing technology, specifically to a cable resonance fatigue testing device and method. Background Technology

[0002] Cables are tension-bearing cables and are key load-bearing components in large-scale engineering structures. During operation, in addition to bearing the high stresses inherent in the structure itself, cables also withstand alternating loads caused by external excitations. Therefore, the fatigue performance of cables is one of their key performance indicators, and fatigue performance testing is required before practical application.

[0003] To simulate the actual working state of cables, fatigue tests typically involve first stretching the cable to a certain stress level, and then applying alternating loads to achieve the set stress amplitude. Currently, existing cable fatigue testing machines generally use a direct tension method, requiring the actuator to apply both the initial tension and fatigue load, resulting in significant demands on the actuator's loading tonnage and hydraulic system. To reduce the actuator's loading tonnage, a common practice is to use a tool cable to counter-tension the test cable, bearing the initial tension of the test cable. The actuator then only needs to apply the fatigue load, significantly reducing the required loading tonnage. However, even after this, the increase in elastic force generated when the cable reaches the set stress amplitude is still substantial, resulting in significant demands on the actuator and hydraulic system, and high overall equipment costs and installation space requirements. Summary of the Invention

[0004] This application provides a cable resonance fatigue testing device and method, which can solve the technical problems of huge loading tonnage of actuators and huge oil source requirements in the existing cable resonance fatigue test.

[0005] In a first aspect, embodiments of this application provide a cable resonance fatigue testing apparatus for conducting resonance fatigue tests on test cables, the cable resonance fatigue testing apparatus comprising: A first reaction seat and a second reaction seat are arranged at intervals relative to each other, and a slidable connector is provided between the first reaction seat and the second reaction seat. One end of the test cable is anchored to the first reaction seat, and the other end of the test cable is anchored to the connector. A tool cable, one end of which is anchored to the connector, and the other end of which passes through the second reaction seat and is connected to a pretensioning assembly for applying pretension to the tool cable. The tool cable is coaxially arranged with the test cable to form counter-tensioning. An actuator is disposed between the second reaction seat and the connecting member to drive the connecting member to reciprocate between the first reaction seat and the second reaction seat; An inertial container, one end of which is connected to the connector and the other end of which is fixed to the third reaction seat, wherein the inertial force generated by the inertial container cancels out the elastic force generated by the repeated stretching of the test cable and the tool cable.

[0006] In conjunction with the first aspect, in one embodiment, the connector includes: A linear guide rail and a connecting seat slidably connected to the linear guide rail, the guide rail being arranged along the axial direction of the test cable, so that the connecting seat reciprocates in a direction toward either the first reaction seat or the second reaction seat.

[0007] In conjunction with the first aspect, in one embodiment, the connecting seat is a hollow box, the box including at least a first side plate and a second side plate disposed opposite to each other, the first side plate having a first anchoring hole for anchoring the test cable, and the second side plate having a second anchoring hole for anchoring the tool cable.

[0008] In conjunction with the first aspect, in one embodiment, one end of the test cable is anchored to the first reaction seat by a cable anchor, the other end of the test cable passes through the first anchoring hole and is anchored to the connecting seat by a cable anchor, and one end of the tool cable passes through the second anchoring hole and is anchored to the connecting seat by a cable anchor.

[0009] In conjunction with the first aspect, in one embodiment, a slider is fixed at each of the four corners of the bottom surface of the box, and there are two linear guides arranged parallel to each other. The two sliders arranged along the length direction of the bottom surface of the box and the same linear guide form a sliding pair.

[0010] In conjunction with the first aspect, in one embodiment, the inertia container is connected to the connector via a lever assembly, the input end of the lever assembly is hinged to the connector, the output end of the lever assembly is hinged to the inertia container, and the fulcrum of the lever assembly is hinged to a support hinge located between the inertia container and the connector.

[0011] In conjunction with the first aspect, in one embodiment, the lever assembly includes a lever and a support rod, the support rod being connected to the connector and extending along the sliding direction of the connector, one end of the lever being connected to the extended end of the support rod away from the connector, the other end of the lever being connected to the inertial container, and the lever and the support rod being arranged perpendicular to each other.

[0012] In conjunction with the first aspect, in one embodiment, the pretensioning component includes: A reaction beam is provided at the end of the second reaction seat away from the connector. A lifting member is provided between the reaction beam and the second reaction seat. A tension fixing nut is provided on the reaction beam. The tightened end of the tension fixing nut is provided with a tension connecting plate for anchoring to the end of the tool cable that passes through the second reaction seat.

[0013] In conjunction with the first aspect, in one embodiment, actuators are arranged on both sides of the tool cable.

[0014] Secondly, embodiments of this application provide a cable resonance fatigue test method, wherein a cable resonance fatigue test is performed on a test cable based on the cable resonance fatigue test apparatus described in any of the above embodiments, characterized in that the cable resonance fatigue test method includes: The two ends of the test cable are anchored to the first reaction seat and the connector respectively, and the two ends of the tool cable are anchored to the connector and the second reaction seat respectively, so that the test cable and the tool cable are tensioned in opposite directions; The tool cable is pre-tensioned by the pre-tensioning assembly to bring the test cable to a preset initial stress level and maintain the tension of the tool cable. Adjust the inertial mass of the inertial container so that the natural frequencies of the connector, test cable, tool cable and inertial container approach the preset excitation frequency of the actuator; The actuator is activated at a preset excitation frequency, driving the connecting member to slide back and forth. The test cable and the tool cable resonate, and the actuator continuously applies alternating loads to the test cable and the tool cable until the fatigue test of the test cable is completed.

[0015] The beneficial effects of the technical solutions provided in this application include: This embodiment of the application introduces an inertial container into the cable resonance fatigue testing device, causing the entire assembly consisting of the connector, test cable, tool cable, and inertial container to resonate at a specific frequency. In the resonant state, the inertial force generated by the inertial container cancels out the elastic force generated by the deformation of the test cable and tool cable. Therefore, the force required to drive the reciprocating motion of the connector, i.e., the fatigue load required by the actuator, is greatly reduced. The main load that the actuator in this embodiment needs to overcome is transformed into an inertial force that can be actively canceled out by adjusting the inertial mass; only the remaining damping force needs to be overcome, thereby reducing the overall cost of the equipment and the space required for installation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a cable resonance fatigue testing device provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a connector provided in one embodiment of this application; Figure 3 This is a schematic diagram of the structure of a cable resonance fatigue testing device provided in another embodiment of this application; Figure 4 This is a schematic diagram of the structure of a cable resonance fatigue testing device provided in another embodiment of this application; Figure 5 A diagram showing the relationship between inertial force and elastic force and the inertial mass of the inertial container, provided for embodiments of this application.

[0018] In the diagram: 1. First reaction seat; 2. Second reaction seat; 3. Connector; 31. Linear guide rail; 32. Connecting seat; 33. Slider; 4. Test cable; 5. Tool cable; 6. Pre-tightening assembly; 61. Reaction beam; 62. Lifting component; 63. Tensioning fixing nut; 64. Tensioning connecting plate; 7. Actuator; 8. Inertia container; 9. Lever assembly; 91. Lever; 92. Support rod; 10. Support hinge; 11. Third reaction seat; 12. Cable anchor; 13. Counterweight. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0020] This application provides a cable resonance fatigue testing device and method, which can solve the technical problems of huge loading tonnage of actuators and huge oil source requirements in the existing cable resonance fatigue test.

[0021] In a first aspect, embodiments of this application provide a cable resonance fatigue testing device for conducting resonance fatigue tests on test cables.

[0022] Figure 1 This is a schematic diagram of the structure of a cable resonance fatigue testing device provided in one embodiment of this application. See also... Figure 1 The cable resonance fatigue testing device includes: a first reaction seat 1 and a second reaction seat 2 arranged at intervals opposite to each other, a slidable connector 3 between the first reaction seat 1 and the second reaction seat 2, one end of the test cable 4 anchored to the first reaction seat 1, and the other end of the test cable 4 anchored to the connector 3; a tool cable 5, one end of the tool cable 5 anchored to the connector 3, the other end of the tool cable 5 passing through the second reaction seat 2 and connected to a pre-tensioning component 6 for applying pre-tension to the tool cable 5, the tool cable 5 and the test cable 4 being coaxially arranged to form counter-tensioning; an actuator 7, the actuator 7 being arranged between the second reaction seat 2 and the connector 3 to drive the connector 3 to reciprocate between the first reaction seat 1 and the second reaction seat 2; and an inertia container 8, one end of the inertia container 8 being connected to the connector 3, and the other end of the inertia container 8 being fixed to the third reaction seat 11, the inertial force generated by the inertia container 8 being canceled out by the elastic force generated by the repeated stretching of the test cable 4 and the tool cable 5.

[0023] Specifically, the first reaction seat 1 and the second reaction seat 2 are arranged coaxially at intervals. The first reaction seat 1 serves as the fixed end support of the test cable 4, and has a through hole for the test cable 4 to pass through. The second reaction seat 2 serves as the anchor support for the tension end of the tool cable 5 and the mounting base for the actuator 7, and also has a through hole for the tool cable 5 to pass through. The test cable 4 is the cable specimen being tested, and the cross-sectional area and stiffness of the tool cable 5 are the same as the relevant parameters of the test cable 4. The inertia container 8 is a device that can convert a small-mass physical entity into a large equivalent inertial mass through an internal mechanical transmission mechanism. In the embodiments of this application, the inertial mass of the inertia container 8 can be adjusted.

[0024] In this embodiment, the test cable 4, tool cable 5, connector 3, and inertial container 8 constitute a forced vibration system. When the inertial mass of the inertial container 8 is adjusted so that the system's natural frequency is close to the excitation frequency of the actuator 7, the system enters a resonance state. In the resonance state, the actuator 7 drives the connector 3 to reciprocate, and the displacement of the connector 3 is synchronously transmitted to the test cable 4 and tool cable 5, causing elastic deformation of the test cable 4 and tool cable 5. The elastic deformation generates elastic force, the amplitude of which is proportional to the displacement amplitude and the system stiffness, and the direction of the elastic force always points to the equilibrium position. The inertial container 8 moves synchronously with the connector 3. Due to the movement of the inertial mass inside the inertial container 8, an inertial force is generated. The amplitude of the inertial force is proportional to the acceleration amplitude and the equivalent total mass, and the direction of the inertial force is always opposite to the acceleration direction. Thus, the inertial force and the elastic force are equal in magnitude and opposite in direction, and the inertial force and the elastic force cancel each other out inside the system. Therefore, in this embodiment, the driving force required by the actuator 7 is only needed to overcome various damping forces existing in the system, achieving small-tonnage loading.

[0025] In this embodiment, the connector 3 includes a linear guide rail 31 and a connecting seat 32 slidably connected to the linear guide rail 31. The guide rail 31 is arranged along the axial direction of the test cable 4 so that the connecting seat 32 slides back and forth in the direction toward the first reaction seat 1 or toward the second reaction seat 2.

[0026] Figure 2 This is a schematic diagram of the structure of a connector provided in one embodiment of this application. See also... Figure 2 Specifically, the connecting seat 32 is a hollow box, which includes at least a first side plate and a second side plate arranged opposite to each other. The first side plate has a first anchoring hole for anchoring the test cable 4, and the second side plate has a second anchoring hole for anchoring the tool cable 5.

[0027] The first and second side plates are two perpendicular side plates arranged opposite each other along the axial direction of the test cable 4. Both side plates can be made of high-strength steel plates. The first side plate has a first anchoring hole, into which one end of the test cable 4 is inserted for anchoring. The second side plate has a second anchoring hole, into which one end of the tool cable 5 is inserted for anchoring. The centers of the first and second anchoring holes are aligned to ensure that the axes of the test cable 4 and the tool cable 5 are collinear. In this embodiment, the hollow connecting seat 32 facilitates the installation of the test cable 4 and the tool cable 5, and the first and second anchoring holes ensure that the stress borne by the test cable 4 is more precise.

[0028] Furthermore, a slider 33 is fixed at each of the four corners of the bottom surface of the box, and there are two linear guide rails 31 arranged parallel to each other. The two sliders 33 arranged along the length of the bottom surface of the box and the same linear guide rail 31 form a sliding pair.

[0029] The bottom surface of the housing is rectangular. A linear guide rail 31 and a slider 33 are fixedly installed at each of the four corners of the rectangle, forming a flat surface. Corresponding to the layout of the sliders 33, two linear guide rails 31 are installed. The center lines of the two linear guide rails 31 are parallel to the axis of the test cable 4, and the distance between the two linear guide rails 31 is equal to the center distance between the two sliders 33 arranged along the length of the bottom surface of the housing. The length of the linear guide rails 31 can be set according to the required sliding range of the connector 3 during the actual test. In this embodiment, the arrangement of the linear guide rails 31 and sliders 33 can improve the overall rigidity of the connector 3, while ensuring accurate axial positioning of the connector 3 during reciprocating sliding. In some other embodiments of this application, the connecting seat 32 can also be set to other shapes, as long as it meets the reciprocating sliding performance and anchoring performance of the connecting seat 32, and is not limited here.

[0030] In this embodiment, one end of the test cable 4 is anchored to the first reaction seat 1 via the cable anchor 12, and the other end of the test cable 4 passes through the first anchoring hole and is anchored to the connecting seat 32 via the cable anchor 12. One end of the tool cable 5 passes through the second anchoring hole and is anchored to the connecting seat 32 via the cable anchor 12.

[0031] Specifically, the cable anchor 12 can be a hot-cast anchor, a cold-cast anchor, or a wedge-type anchor. An anchor plate with a through hole can be fixed to the first reaction seat 1. One end of the test cable 4 passes through the through hole of the first reaction seat 1, and the cable anchor 12 is fastened to the first reaction seat 1 on the other side by a locking nut, thus anchoring one end of the test cable 4. The other end of the test cable 4 passes through the first anchor hole of the first side plate of the connecting seat 32 from the outside, and is fastened to the inner side of the first side plate inside the connecting seat 32 housing by a locking nut, thereby directly transmitting the axial movement of the connecting seat 32 to the test cable 4. One end of the tool cable 5 passes through the second anchor hole of the second side plate of the connecting seat 32 from the outside, and is fastened to the inner side of the second side plate inside the connecting seat 32 housing by a locking nut.

[0032] In this embodiment of the application, the inertia container 8 is connected to the connector 3 via a lever assembly 9. The input end of the lever assembly 9 is hinged to the connector 3, the output end of the lever assembly 9 is hinged to the inertia container 8, and the fulcrum of the lever assembly 9 is hinged to the support hinge 10 located between the inertia container 8 and the connector 3.

[0033] Figure 3 A schematic diagram of the structure of a cable resonance fatigue testing device provided in another embodiment of this application. See also... Figure 3Specifically, the lever assembly 9 includes a lever 91 and a support rod 92. The support rod 92 is connected to the connector 3 and extends along the sliding direction of the connector 3. One end of the lever 91 is connected to the extended end of the support rod 92 away from the connector 3, and the other end of the lever 91 is connected to the inertial container 8. The lever 91 and the support rod 92 are arranged perpendicular to each other.

[0034] The support rod 92 is specifically a straight rod fixedly connected to the connecting seat 32 of the connector 3. The support rod 92 will move axially with the connector 3. The extension end of the support rod 92 away from the connector 3 is connected to the lever 91, and the lever 91 is fixed to the foundation by the support hinge 10. When the connector 3 is displaced under the drive of the actuator 7, the lever 91 rotates around the fulcrum, and the output end is displaced. Based on the principle of the lever 91, the displacement is amplified. After the displacement of the end of the inertia container 8 increases, the physical mass required to generate the same amplitude of inertial force is reduced. Thus, the lever assembly 9 reduces the inertial mass requirement of the inertia container 8 by amplifying the displacement.

[0035] The inertial container 8 can be a rack and pinion type inertial container, a ball screw type inertial container, a gear pump type inertial container, or a spiral tube hydraulic type inertial container. Furthermore, Figure 4 A schematic diagram of the cable resonance fatigue testing apparatus provided in another embodiment of this application. See also... Figure 4 The inertial container 8 located at the other end of the lever 91 can be replaced with a counterweight 13. The inertial force is provided by the actual mass of the counterweight 13, thereby eliminating the response delay caused by the back clearance of the inertial container 8. At the same time, replacing the complex inertial container 8 with the simpler counterweight 13 can further reduce the manufacturing cost of the overall test device.

[0036] In this embodiment, the pretensioning component 6 includes: a reaction beam 61 disposed at the end of the second reaction seat 2 away from the connector 3, a lifting member 62 disposed between the reaction beam 61 and the second reaction seat 2, and a tension fixing nut 63 disposed on the reaction beam 61, and a tension connecting plate 64 disposed at the tightening end of the tension fixing nut 63 for anchoring to the end of the tool cable 5 passing through the second reaction seat 2.

[0037] Specifically, the lifting component 62 is a jack, and two jacks with a gap between them are provided between the reaction beam 61 and the second reaction seat 2. The tensioning connecting plate 64 and the tensioning fixing nut 63 are both located in the gap between the two jacks. One end of the tool cable 5 passes through the second reaction seat 2 and is fixed to the side of the second reaction seat 2 facing the reaction beam 61 by the cable anchor 12. The tensioning fixing nut 63 is connected to the tensioning connecting plate 64, thereby pressing and fixing the tensioning connecting plate 64 to the reaction beam 61.

[0038] In this embodiment of the application, actuators 7 are arranged on both sides of the tool cable 5.

[0039] Specifically, the two actuators 7 are located on the radial sides of the tool cable 5. During the test, the two actuators 7 work synchronously, which can further improve the load simulation accuracy and the reliability of the results.

[0040] Secondly, embodiments of this application provide a cable resonance fatigue test method, wherein a cable resonance fatigue test device based on any of the above embodiments is used to perform a resonance fatigue test on a test cable, characterized in that the cable resonance fatigue test method specifically includes the following steps: Step S1: Anchor both ends of the test cable to the first reaction seat and the connector respectively, and anchor both ends of the tool cable to the connector and the second reaction seat respectively, so that the test cable and the tool cable are tensioned in opposite directions.

[0041] Specifically, during the assembly phase of the test, one end of the test cable is first fixed to the first reaction seat, and the other end is fixed to the connector. Then, one end of the tool cable is fixed to the connector, and the other end of the tool cable passes through the second reaction seat and is ready to connect to the pretensioning assembly. This ensures that the test cable and the tool cable are coaxially tensioned in opposite directions.

[0042] Step S2: Apply pretension to the tool cable through the pretensioning assembly to bring the test cable to the preset initial stress level and maintain the tension state of the tool cable.

[0043] Specifically, the lifting member in the drive pretensioning assembly tensions the tool cable. Since the tool cable and the test cable are connected in series via a connector, tensioning the tool cable simultaneously tensions the test cable. The stress in the test cable can be controlled by the output force of the lifting member. Therefore, the specific calculation method for the stress in the test cable is as follows:

[0044] in, This indicates the output force of the lifting component. Indicates the stress in the test cable. This represents the cross-sectional area of ​​the test cable. Therefore, by controlling the output force of the lifting device, the stress in the test cable can reach the preset target initial stress value. After reaching the preset target initial stress value, the tool cable is anchored on the second reaction seat. Subsequently, the lifting device can unload the load. At this time, the tension of the tool cable is equal in magnitude and opposite in direction to the tension of the test cable.

[0045] Step S3: Adjust the inertial mass of the inertial container so that the natural frequencies of the connector, test cable, tool cable and inertial container are close to the preset excitation frequency of the actuator.

[0046] Specifically, the test cable, tool cable, connectors, and inertial container constitute a forced vibration system. Among them:

[0047]

[0048] in, Indicates the actuator output, Represents the inertial force of the system. Indicates the system damping force. This represents elastic force, which is generated by the elastic deformation of the test cable and the tool cable. Indicates the physical mass of the connector. The inertial mass of the container is represented. This indicates the acceleration of the connecting component. This represents the equivalent viscous damping coefficient of the system. Indicates the speed of the connecting parts. Indicates the axial tensile stiffness of the test cable. Indicates the axial tensile stiffness of the tool cable. Indicates the total stiffness of the system. This indicates the displacement of the connecting plate.

[0049] The system's natural frequency is:

[0050] in, This represents the system's natural frequency.

[0051] Therefore, elastic force can be expressed as:

[0052] Therefore, it can be seen that by adjusting the inertial mass of the inertial container, the total mass of the system can be changed, which in turn can change the natural frequency of the system, so that the natural frequency of the system approaches the preset excitation frequency of the actuator, and the system is in a resonant state.

[0053] Step S4: Start the actuator at a preset excitation frequency to drive the connector to slide back and forth, causing the test cable and tool cable to resonate. The actuator continuously applies alternating loads to the test cable and tool cable until the fatigue test of the test cable is completed.

[0054] Specifically, the actuator is activated at a preset excitation frequency to drive the connecting parts to slide back and forth, and the test cable and the tool cable extend or shorten synchronously.

[0055] The system's inertial force and elastic force are out of phase. By adjusting the inertial mass, the inertial force and elastic force can be balanced, and the resultant force is 0. Therefore, the actuator only needs to overcome the system's damping force, and the actuator's output amplitude is significantly reduced compared to traditional test methods.

[0056] Technical features and effects not mentioned in the embodiments of this application can be found in the previous embodiment, and will not be repeated here.

[0057] In a specific embodiment, let the length of the test cable be... The length of the tool cable is The quality of the connecting plate is Cross-sectional area of ​​the test cable and tool cable cross-sectional area All , test cable elastic modulus and tool cable elastic modulus All Then the system stiffness is:

[0058] If no inertial container is configured, the system frequency is: The corresponding frequency is 24.6 Hz, which is much higher than the excitation capability of conventional actuators.

[0059] Test conditions , The system damping ratio is , Figure 5 A diagram showing the relationship between inertial forces, elastic forces, and the inertial mass of the inertial container, provided for embodiments of this application. See also... Figure 5 , Figure 5 The horizontal axis represents the inertial mass of the inertial container ( b ) and the quality of the connector itself ( m The ratio of ) Figure 5 The vertical axis represents the amplitude of each dynamic force in the system under the test conditions. In this embodiment, after introducing inertial mass, the inertial force continuously increases, and the amplitudes of both the inertial force and the elastic force first decrease and then increase with the increase of the inertial mass. When the inertial mass is... At this point, the inertial force and the elastic force reach equilibrium, and the resultant force is 0. The actuator output force is reduced from 3665.6 kN in the traditional scheme to 390.63 kN, a reduction of approximately 89.3%.

[0060] This embodiment of the application introduces an inertial container into the cable resonance fatigue testing device, causing the entire assembly consisting of the connector, test cable, tool cable, and inertial container to resonate at a specific frequency. In the resonant state, the inertial force generated by the inertial container cancels out the elastic force generated by the deformation of the test cable and tool cable. Therefore, the force required to drive the reciprocating motion of the connector, i.e., the fatigue load required by the actuator, is greatly reduced. The main load that the actuator in this embodiment needs to overcome is transformed into an inertial force that can be actively canceled out by adjusting the inertial mass; only the remaining damping force needs to be overcome, thereby reducing the overall cost of the equipment and the space required for installation.

[0061] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0062] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0063] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A cable resonance fatigue testing device for conducting resonance fatigue tests on test cables, characterized in that, The cable resonance fatigue testing device includes: A first reaction seat (1) and a second reaction seat (2) are arranged at intervals relative to each other. A slidable connector (3) is provided between the first reaction seat (1) and the second reaction seat (2). One end of the test cable (4) is anchored to the first reaction seat (1), and the other end of the test cable (4) is anchored to the connector (3). Tool cable (5), one end of which is anchored to the connector (3), the other end of which passes through the second reaction seat (2) and is connected to the pretensioning assembly (6) for applying pretension to the tool cable (5), the tool cable (5) and the test cable (4) are coaxially arranged to form opposing tension; Actuator (7), which is disposed between the second reaction seat (2) and the connector (3) to drive the connector (3) to reciprocate between the first reaction seat (1) and the second reaction seat (2); An inertial container (8) is connected at one end to the connector (3) and at the other end to the third reaction seat (11). The inertial force generated by the inertial container (8) cancels out the elastic force generated by the repeated stretching of the test cable (4) and the tool cable (5). The inertia container (8) is connected to the connector (3) via a lever assembly (9). The input end of the lever assembly (9) is hinged to the connector (3), and the output end of the lever assembly (9) is hinged to the inertia container (8). The fulcrum of the lever assembly (9) is hinged to a support hinge (10) located between the inertia container (8) and the connector (3). The lever assembly (9) includes a lever (91) and a support rod (92). The support rod (92) is connected to the connector (3) and extends along the sliding direction of the connector (3). One end of the lever (91) is connected to the extension end of the support rod (92) away from the connector (3), and the other end of the lever (91) is connected to the inertia container (8). The lever (91) and the support rod (92) are arranged perpendicular to each other.

2. The cable resonance fatigue testing device according to claim 1, characterized in that, The connector (3) includes: A linear guide (31) and a connecting seat (32) slidably connected to the linear guide (31), the guide of the linear guide (31) being arranged along the axial direction of the test cable (4) so ​​that the connecting seat (32) slides back and forth in the direction toward the first reaction seat (1) or toward the second reaction seat (2).

3. The cable resonance fatigue testing device according to claim 2, characterized in that, The connecting seat (32) is a hollow box. The box includes at least a first side plate and a second side plate arranged opposite to each other. The first side plate has a first anchoring hole for anchoring the test cable (4), and the second side plate has a second anchoring hole for anchoring the tool cable (5).

4. The cable resonance fatigue testing device according to claim 3, characterized in that, One end of the test cable (4) is anchored to the first reaction seat (1) through the cable anchor (12), and the other end of the test cable (4) passes through the first anchor hole and is anchored to the connecting seat (32) through the cable anchor (12). One end of the tool cable (5) passes through the second anchor hole and is anchored to the connecting seat (32) through the cable anchor (12).

5. The cable resonance fatigue testing device according to claim 3, characterized in that, At each of the four corners of the bottom surface of the box, there is a slider (33). There are two linear guides (31), which are arranged parallel to each other. The two sliders (33) arranged along the length of the bottom surface of the box and the same linear guide (31) form a sliding pair.

6. The cable resonance fatigue testing device according to claim 1, characterized in that, The pretensioning component (6) includes: A reaction beam (61) is provided at the end of the second reaction seat (2) away from the connector (3). A lifting member (62) is provided between the reaction beam (61) and the second reaction seat (2). A tension fixing nut (63) is provided on the reaction beam (61). The tightening end of the tension fixing nut (63) is provided with a tension connecting plate (64) for anchoring to the end of the tool cable (5) that passes through the second reaction seat (2).

7. The cable resonance fatigue testing device according to claim 1, characterized in that, Actuators (7) are arranged on both sides of the tool cable (5).

8. A method for cable resonance fatigue testing, comprising conducting resonance fatigue tests on a test cable based on the cable resonance fatigue testing apparatus according to any one of claims 1 to 7, characterized in that, The cable resonance fatigue test method includes: The two ends of the test cable (4) are anchored to the first reaction seat (1) and the connector (3) respectively, and the two ends of the tool cable (5) are anchored to the connector (3) and the second reaction seat (2) respectively, so that the test cable (4) and the tool cable (5) are tensioned in opposite directions; The tool cable (5) is pre-tensioned by the pre-tensioning component (6) so that the test cable (4) reaches the preset initial stress level and the tension state of the tool cable (5) is maintained. Adjust the inertial mass of the inertial container (8) so that the natural frequencies of the connector (3), test cable (4), tool cable (5) and inertial container (8) approach the preset excitation frequency of the actuator (7); The actuator (7) is started at a preset excitation frequency, driving the connector (3) to slide back and forth. The test cable (4) and the tool cable (5) resonate. The actuator (7) continuously applies alternating loads to the test cable (4) and the tool cable (5) until the fatigue test of the test cable (4) is completed.

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