Pre-stressed Anti-vibration hammer and pre-stress determination method and system

Abstract

The present application provides a pre-stressed anti-vibration hammer and a pre-stress determination method and system, the pre-stressed anti-vibration hammer comprising a gapped steel strand, an assembly integrated hammer head and an anchoring clamp, wherein the gapped steel strand comprises a central layer round wire, a middle layer molded wire and an outer layer round wire from inside to outside; a gap is provided between the central layer round wire and the middle layer molded wire, and the gap is filled with a lubricating grease, such that the friction resistance between the central layer round wire and the middle layer molded wire is reduced, and pre-applying a stress to the central layer round wire is facilitated; the middle layer molded wire is of an arch structure, and the arch body structure increases the moment of inertia for a circle center, such that the bending rigidity of the steel strand is enhanced; and two ends of the central layer round wire are connected with the assembly integrated hammer head, the anchoring clamp is assembled in a hollow portion of one end of the assembly integrated hammer head away from the central layer round wire, and is configured to clamp the central layer round wire to which a target stress is pre-applied, a tensile stress generated by an impact load firstly counteracts the tensile stress generated between the outer layer round wire and a middle layer strand after the stress is pre-applied, and the bending rigidity of the steel strand can be increased.

Description

A prestressed anti-vibration hammer and a method and system for determining prestress

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311430936.3, application date October 31, 2023, and application name “A prestressed anti-vibration hammer and a method and system for determining prestress”, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of vibration damping devices for power transmission lines, and in particular to a prestressed anti-vibration hammer and a method and system for determining the prestress. Background Art

[0004] In areas with strong winds, the conductors of power transmission projects will be subjected to significant impact due to wind swaying. Under such significant impact, the conductors will undergo dynamic responses such as vibration, swing or deformation, causing fatigue of the conductor material. In severe cases, strand and line breakage accidents may even occur. Therefore, anti-vibration hammers are usually installed on transmission lines to absorb or weaken vibration energy, change the line swing frequency, prevent line vibration or swaying, and keep the conductors in a relatively stable state.

[0005] The current bending stiffness design of the anti-vibration hammer steel strand is designed to meet the anti-vibration performance of the anti-vibration hammer under light wind vibration conditions, and is suitable for the dynamic response of the conductor under light wind vibration conditions; however, under the action of large impact loads in strong wind areas, the steel strand of the anti-vibration hammer on the conductor is prone to obvious plastic deformation due to insufficient bending stiffness, thereby affecting its anti-vibration effect; and the existing dynamic characteristic test of the anti-vibration hammer is also a test method under light wind vibration conditions. The value range of the bending stiffness and damping coefficient of the anti-vibration hammer steel strand is not suitable for the calculation of the dynamic characteristics of the anti-vibration hammer under strong wind and large impact loads.

[0006] Summary of the Invention

[0007] In order to overcome the above-mentioned deficiencies of the prior art, the present application proposes a prestressed anti-vibration hammer, comprising:

[0008] Gap-type steel strand 1, assembled integral hammer head 3 and anchoring fixture;

[0009] The gap-shaped steel strand 1 includes, from the inside to the outside, a center layer round wire 13, an intermediate layer round wire 12, and an outer layer round wire 11. A gap 14 is provided between the center layer round wire 13 and the intermediate layer round wire 12, and the gap 14 is filled with grease. The lengths of the intermediate layer round wire 12 and the outer layer round wire 11 are shorter than those of the center layer round wire 13. The intermediate layer round wire 12 is an arch structure.

[0010] The two ends of the central layer circular wire 13 are respectively connected to an assembled integral hammer head 3, and the middle position of each assembled integral hammer head 3 away from one end of the central layer circular wire 13 is a hollow part, and the anchoring fixture is assembled in the hollow part;

[0011] The anchoring fixture is used to clamp the center layer round wire 13 after the target stress is pre-applied by an external tensioning tool; the gap-type steel strand 1 and the assembled integral hammer head 3 are coupled and connected through the center layer round wire 13 after the target stress is pre-applied.

[0012] In some embodiments, the assembled integral hammer head 3 has a center hole at one end close to the center layer circle line 13;

[0013] The two ends of the center layer circular wire 13 pass through the center holes of the assembled integral hammer head 3 at one end, respectively, and the anchoring fixture is clamped on the center layer circular wire 13 that has passed through the center hole and has been pre-stressed with the target stress;

[0014] The central layer round wire 13 of the gap-type steel strand 1 passing through the central hole is clamped by the anchoring clamp and coupled with the assembled integral hammer head 3 with the anchoring clamp built in.

[0015] In some embodiments, the anti-vibration hammer further includes a wire clamp 2 , one end of which is clamped in the middle of the outer round wire 11 and the other end is sleeved on the external conductor; the assembled integral hammer head 3 is symmetrically distributed on both sides of the wire clamp 2 .

[0016] In some embodiments, the assembled integral hammer head 3 includes a concave hammer head 23 and a convex hammer head 31, wherein the concave hammer head 23 is concave inwardly at one end facing away from the line clamp 2 and closely adheres to the convex hammer head 31 and protrudes outwardly; the convex hammer head 31 is open and hollow at one end facing away from the concave hammer head 23, and the anchoring fixture is assembled in the hollow part of the convex hammer head 31;

[0017] The center holes include a first center hole 22 opened in the concave hammer head and a second center hole 33 opened in the convex hammer head 31 ; the center layer circular wire 13 passes through the first center hole 22 and the second center hole 33 in sequence.

[0018] In some embodiments, the diameters of the first center hole 22 and the second center hole 33 are smaller than the diameter of the gap-type steel strand 1 and larger than the diameter of the center layer round wire 13 .

[0019] In some embodiments, the concave hammer head 23 has a U-shaped structure at one end close to the wire clamp 2, with the opening of the U-shaped structure facing the wire clamp 2. A steel sleeve 21 is fixedly installed in the concave part of the opening of the U-shaped structure, and the steel sleeve 21 is sleeved on the outside of the outer round wire 11.

[0020] In some embodiments, an anchoring fixture embedding groove 32 is provided on each of the upper and lower edges of the hollow portion of the convex hammer head 31 . The anchoring fixture embedding groove 32 is close to the second center hole 33 , and the anchoring fixture is assembled in the anchoring fixture embedding groove 32 .

[0021] In some embodiments, the anchoring clamp includes an upper clamp 41 and a lower clamp 42, and the upper clamp 41 and the lower clamp 42 are both wedge-shaped structures. The upper clamp 41 is clamped with the anchoring clamp embedded groove 32 set at the upper edge, and the lower clamp 42 is clamped with the anchoring clamp embedded groove 32 set at the lower edge. After clamping, the wedge-shaped structures of the upper clamp 41 and the lower clamp 42 are opposite to each other at the side, and the center layer circular wire 13 is clamped between the upper clamp 41 and the lower clamp 42.

[0022] In some embodiments, the intermediate layer profile 12 comprises:

[0023] The plurality of profile wires have a cross section of a quadrilateral that is wide at the top and narrow at the bottom. The plurality of profile wires are twisted and extruded in the same direction around the central layer circular wire 13 to form an arch structure.

[0024] This application also proposes a method for determining the prestressing of a vibration-damping steel strand, comprising:

[0025] Performing a dynamic test on a non-prestressed anti-vibration hammer steel strand to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load;

[0026] Performing a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load;

[0027] Based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load, the value of the prestress is adjusted to obtain the target stress of the anti-vibration hammer steel strand;

[0028] Wherein, the anti-vibration hammer steel strand is the aforementioned gap-type steel strand of the anti-vibration hammer.

[0029] In some embodiments, adjusting the value of the prestress based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load to obtain the target stress of the anti-vibration hammer steel strand comprises:

[0030] If the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the same impact load is within the preset stiffness ratio range, the prestress value is used as the target stress of the anti-vibration hammer steel strand;

[0031] If under the same impact load, the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand is not within the preset stiffness ratio range, the prestress is adjusted and the second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand is recalculated until the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness is within the stiffness ratio range. The prestress value at this time is used as the target stress of the anti-vibration hammer steel strand.

[0032] In some embodiments, the performing of a dynamic test on a non-prestressed anti-vibration hammer steel strand to obtain a first dynamic bending stiffness of the anti-vibration hammer steel strand under an impact load comprises:

[0033] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand.

[0034] The damping ratio of the anti-vibration hammer steel strand is obtained by applying an impact load to the end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration.

[0035] The vibration signal of the anti-vibration hammer steel strand after the impact load is applied is processed by a data acquisition and analysis instrument to obtain the natural frequency of the anti-vibration hammer steel strand;

[0036] The static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand under impact load are used in combination with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load.

[0037] In some embodiments, obtaining the static bending stiffness of the anti-vibration hammer steel strand by using the weight of a weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand comprises:

[0038] Use the strain gauge to obtain the weight of the weight at the critical yield point of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand at this time, which is recorded as the maximum deflection;

[0039] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight and the maximum deflection combined with the calculation formula of the static bending stiffness.

[0040] In some embodiments, the static bending stiffness is calculated as follows:

[0041] Wherein, k represents the static bending stiffness of the anti-vibration hammer steel strand; F represents the load at the free end of the anti-vibration hammer steel strand, that is, the weight of the weight connected to the anti-vibration hammer steel strand; l represents the distance from the midpoint of the anti-vibration hammer steel strand to the connection between the anti-vibration hammer steel strand and the hammer head; h ... max Indicates the maximum deflection.

[0042] In some embodiments, obtaining the damping ratio of the anti-vibration hammer steel strand by applying an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration includes:

[0043] Apply an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to obtain a vibration attenuation curve of the anti-vibration hammer steel strand;

[0044] According to the amplitude values ​​of two different vibration periods in the vibration attenuation curve and combined with the calculation formula of the damping ratio, the damping ratio of the anti-vibration hammer steel strand is obtained.

[0045] In some embodiments, the damping ratio is calculated as:

[0046] Where, ζ represents the damping ratio of the anti-vibration hammer steel strand; b represents the interval between two vibration cycles; a represents the ath vibration cycle; u a Indicates the amplitude value of the ath vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand; u a+b It represents the amplitude value of the a+bth vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand.

[0047] In some embodiments, the method of using the static bending stiffness, damping ratio, natural frequency, and excitation frequency of the anti-vibration hammer steel strand when subjected to an impact load, in combination with a calculation formula for the dynamic bending stiffness of the anti-vibration hammer steel strand, to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load includes:

[0048] The damping of the anti-vibration hammer steel strand is calculated by using the mass, damping ratio and natural frequency of the anti-vibration hammer steel strand and combining the damping calculation formula.

[0049] The first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load is calculated by using the static bending stiffness, damping and excitation frequency of the anti-vibration hammer steel strand when subjected to the impact load, combined with the dynamic bending stiffness calculation formula.

[0050] In some embodiments, the dynamic bending stiffness calculation formula is:

[0051] Among them, k d represents the dynamic bending stiffness of the anti-vibration hammer steel strand, k represents the static bending stiffness of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand; ω represents the excitation frequency of the anti-vibration hammer steel strand; c represents the damping of the anti-vibration hammer steel strand.

[0052] Based on the same inventive concept, the present application also provides a system for determining the prestress of a vibration-damping steel strand, comprising:

[0053] A first dynamic bending stiffness determination module is used to perform a dynamic test on a vibration damper steel strand without prestressing to obtain a first dynamic bending stiffness of the vibration damper steel strand under an impact load;

[0054] The second dynamic bending stiffness determination module is used to perform a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load;

[0055] A target stress determination module is configured to adjust the value of the prestress based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load to obtain the target stress of the anti-vibration hammer steel strand;

[0056] Wherein, the anti-vibration hammer steel strand is the aforementioned gap-type steel strand of the anti-vibration hammer.

[0057] In some embodiments, the target stress determination module is specifically configured to:

[0058] If the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the same impact load is within the preset stiffness ratio range, the prestress value is used as the target stress of the anti-vibration hammer steel strand;

[0059] If under the same impact load, the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand is not within the preset stiffness ratio range, the prestress is adjusted and the second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand is recalculated until the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness is within the stiffness ratio range. The prestress value at this time is used as the target stress of the anti-vibration hammer steel strand.

[0060] In some embodiments, the first dynamic bending stiffness determination module is specifically configured to:

[0061] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand.

[0062] The damping ratio of the anti-vibration hammer steel strand is obtained by applying an impact load to the end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration.

[0063] The vibration signal of the anti-vibration hammer steel strand after the impact load is applied is processed by a data acquisition and analysis instrument to obtain the natural frequency of the anti-vibration hammer steel strand;

[0064] The static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand under impact load are used in combination with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load.

[0065] In some embodiments, the first dynamic bending stiffness determination module obtains the static bending stiffness of the anti-vibration hammer steel strand by using the weight of a weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand, including:

[0066] Use the strain gauge to obtain the weight of the weight at the critical yield point of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand at this time, which is recorded as the maximum deflection;

[0067] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight and the maximum deflection combined with the calculation formula of the static bending stiffness.

[0068] In some embodiments, the calculation formula for the static bending stiffness in the first dynamic bending stiffness determination module is:

[0069] Wherein, k represents the static bending stiffness of the anti-vibration hammer steel strand; F represents the load at the free end of the anti-vibration hammer steel strand, that is, the weight of the weight connected to the anti-vibration hammer steel strand; l represents the distance from the midpoint of the anti-vibration hammer steel strand to the connection between the anti-vibration hammer steel strand and the hammer head; h ... max Indicates the maximum deflection.

[0070] In some embodiments, the first dynamic bending stiffness determination module obtains the damping ratio of the anti-vibration hammer steel strand by applying an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration, including:

[0071] Apply an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to obtain a vibration attenuation curve of the anti-vibration hammer steel strand;

[0072] According to the amplitude values ​​of two different vibration periods in the vibration attenuation curve and combined with the calculation formula of the damping ratio, the damping ratio of the anti-vibration hammer steel strand is obtained.

[0073] In some embodiments, the damping ratio calculation formula in the first dynamic bending stiffness determination module is:

[0074] Where ζ represents the damping ratio of the anti-vibration hammer steel strand; b represents the interval between two vibration cycles; a represents the ath vibration cycle; u a Indicates the amplitude value of the ath vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand; u a+b It represents the amplitude value of the a+bth vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand.

[0075] In some embodiments, the first dynamic bending stiffness determination module uses the static bending stiffness, damping ratio, natural frequency, and excitation frequency of the anti-vibration hammer steel strand when subjected to an impact load, combined with a calculation formula for the dynamic bending stiffness of the anti-vibration hammer steel strand, to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load, including:

[0076] The damping of the anti-vibration hammer steel strand is calculated by using the mass, damping ratio and natural frequency of the anti-vibration hammer steel strand and combining the damping calculation formula.

[0077] The first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load is calculated by using the static bending stiffness, damping and excitation frequency of the anti-vibration hammer steel strand when subjected to the impact load, combined with the dynamic bending stiffness calculation formula.

[0078] In some embodiments, the dynamic bending stiffness calculation formula in the first dynamic bending stiffness determination module is:

[0079] Among them, k d represents the dynamic bending stiffness of the anti-vibration hammer steel strand, k represents the static bending stiffness of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand; ω represents the excitation frequency of the anti-vibration hammer steel strand; c represents the damping of the anti-vibration hammer steel strand.

[0080] Based on the same inventive concept, the present application also provides a computer device, including: one or more processors;

[0081] a memory for storing one or more programs;

[0082] When the one or more programs are executed by the one or more processors, the above-mentioned method for determining the prestressing of the anti-vibration hammer steel strand is implemented.

[0083] Based on the same inventive concept, the present application also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the method for determining the prestressing of the anti-vibration hammer steel strand as described above is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] FIG1 is a partial structural cross-sectional view of a prestressed anti-vibration hammer provided by the present application;

[0085] FIG2 is a top view of the structure of a prestressed anti-vibration hammer provided by the present application;

[0086] FIG3 is a schematic cross-sectional view of a gap-type steel strand;

[0087] Figure 4 is a schematic diagram of the stress on the pre-tensioned gap-type steel strand;

[0088] Figure 5 is a schematic structural diagram of a concave hammer head;

[0089] Figure 6 is a schematic structural diagram of a convex hammer head;

[0090] Figure 7 is a schematic structural diagram of the anchoring fixture;

[0091] FIG8 is a schematic diagram of the structure of the gap-type steel strand near one end of the assembled integral hammer head;

[0092] FIG9 is a flow chart of a method for determining prestressing of a steel strand by an anti-vibration hammer provided in the present application;

[0093] Figure 10 is a schematic diagram of a power test model;

[0094] Figure 11 is the vibration attenuation curve of the steel strand;

[0095] FIG12 is a schematic diagram of a process for adjusting prestress;

[0096] FIG13 is a schematic structural diagram of a system for determining prestressing of a vibration-damping steel strand provided in the present application.

[0097] Among them, 1-gap-type steel strand, 2-wire clamp, 3-assembled integral hammer, 11-outer layer round wire, 12-middle layer profile wire, 13-center layer round wire, 14-gap, 21-steel casing, 22-first center hole, 23-concave hammer, 31-convex hammer, 32-anchoring clamp embedded groove, 33-second center hole, 41-upper clamp, 42-lower clamp, 43-third center hole. DETAILED DESCRIPTION

[0098] The specific implementation methods of this application are further described in detail below with reference to the accompanying drawings.

[0099] Example 1:

[0100] The embodiment of the present application provides a prestressed anti-vibration hammer, as shown in Figures 1 and 2, comprising: a gap-shaped steel strand 1, an assembled integral hammer head 3 and an anchoring fixture; the gap-shaped steel strand 1 comprises, from the inside to the outside, a center layer round wire 13, an intermediate layer profile 12 and an outer layer round wire 11, a gap 14 is provided between the center layer round wire 13 and the intermediate layer profile 12, and the gap 14 is filled with grease; and the length of the intermediate layer profile 12 and the outer layer round wire 11 is shorter than that of the center layer round wire 13; as shown in Figure 3 The middle layer profile 12 is an arch structure; the two ends of the center layer circular wire 13 are respectively connected to an assembled integral hammer head 3, and the middle position of each assembled integral hammer head 3 away from the end of the center layer circular wire 13 is a hollow part, and the anchoring clamp is assembled in the hollow part; the anchoring clamp is used to clamp the center layer circular wire 13 after the target stress is pre-applied by an external tensioning tool; the gap-type steel strand 1 and the assembled integral hammer head 3 are coupled and connected through the center layer circular wire 13 after the target stress is pre-applied.

[0101] As shown in Figure 4, applying pre-tension to the center layer round wire 13 redistributes the stress in the steel strand. Since the outer strands and the middle layer profile wire 12 of the steel strand are twisted, the forces and deformations of these two strands are consistent. Therefore, while the center layer round wire 13 is under tension, the outer layer round wire 11 and the middle layer profile wire 12 are under compression. The tensile stress generated by the vertical impact load must first offset the compressive stress of the outer and middle layer profile wires 12, thereby reducing the tensile stress of the outer and middle layer profile wires 12 of the steel strand. This increases the bending stiffness of the gap-type steel strand 1, resulting in a better vibration damping effect. The pre-stress applied to the center layer round wire 13 is typically 2%T-5%T, where T is the tensile strength of the steel strand.

[0102] Among them, the width of the gap 14 is set to (0.5mm-1mm), and the gap 14 is set between the center layer circular wire 13 and the middle layer profile wire 12; the gap 14 is filled with grease to reduce the friction resistance between the center layer circular wire 13 and the middle layer profile wire 12, so as to facilitate the application of prestress to the center layer circular wire, reduce the wear between the center layer circular wire 13 and the middle layer profile wire 12, and thus reduce the probability of strand breakage and extend the life of the strand.

[0103] The middle layer profile wire 12 includes: a plurality of profile wires, the cross section of the profile wire is a quadrilateral that is wide at the top and narrow at the bottom, and the plurality of profile wires are twisted and extruded in the same direction around the central layer circular wire 13 to form an arch structure.

[0104] Among them, the cross-section of the profile can be approximately a quadrilateral with a wide top and a narrow bottom. The wide top means that the width of the profile is large on the side of the intermittent steel strand 1 close to the outer layer round wire 11, and the narrow bottom means that the width of the profile is small on the side of the intermittent steel strand 1 close to the center layer round wire 13, as shown in Figure 3.

[0105] The arch structure formed by multiple profile wires in the middle layer increases the moment of inertia about the center of the circle and changes the contact between the strands from line to surface contact. Therefore, after the middle layer profile wire 12 is changed from a round wire to a profile wire, the contact surface area between the strands is increased, so that the force between the strands is more uniform, and there will be no stress concentration like when the round wires contact each other, thereby enhancing the bending stiffness; and the moment of inertia of the middle layer profile wire 12 is larger than the moment of inertia of the round wire, thereby increasing the bending stiffness of the middle layer profile wire 12; the center layer round wire 13 and the outer layer round wire 11 of the gap-shaped steel strand 1 are round wires.

[0106] A center hole is provided at one end of the assembled integral hammer head 3 close to the center layer circular wire 13; the two ends of the center layer circular wire 13 pass through the center holes of the assembled integral hammer head 3 at their respective ends, and the anchoring clamp is clamped on the center layer circular wire 13 that has passed through the center hole and pre-applied target stress; the gap-type steel strand 1 is coupled to the assembled integral hammer head 3 with the built-in anchoring clamp through the center layer circular wire 13 that passes through the center hole.

[0107] Among them, the center layer round wire 13 passing through the center hole part is the center layer round wire 13 after the outer layer round wire 11 and the middle layer profile wire 12 are stripped off the gap steel strand 1. The length of the middle layer profile wire 12 and the outer layer round wire 11 is shorter than the center layer round wire 13 because it is necessary to use an external tensioning tool to pre-stress the center layer round wire 13.

[0108] The anti-vibration hammer further includes a wire clamp 2 , one end of which is clamped in the middle of the outer round wire 11 , and the other end of which is sleeved on the external conductor.

[0109] The wire clamp 2 is connected to the external wire through one end and clamps the outer round wire 11, i.e. the gap-type steel stranded wire 1, at the other end to connect the anti-vibration hammer to the external wire; the assembled integral hammer heads 3 are symmetrically distributed on both sides of the wire clamp 2.

[0110] As shown in Figures 5 and 6, the assembled integral hammer head 3 includes a concave hammer head 23 and a convex hammer head 31. The concave hammer head 23 is concave inward at one end away from the line clamp 2 and is close to the convex hammer head 31 protruding outward; the convex hammer head 31 is open and hollow at one end away from the concave hammer head 23, and the opening direction is away from the concave hammer head 23. The anchoring clamp is assembled in the hollow part of the convex hammer head 31; the center hole includes a first center hole 22 opened in the concave hammer head 23 and a second center hole 33 opened in the convex hammer head 31; the center layer circle line 13 passes through the first center hole 22 and the second center hole 33 in sequence.

[0111] Among them, the center layer round wire 13 passes through the first center hole 22 and the second center hole 33 in sequence, and then enters the inside of the anchoring clamp. The center layer round wire 13 is prestressed by using a tensioning tool, and the prestressed center layer round wire 13 is clamped by the anchoring clamp. The length of the center layer round wire 13 after the outer layer round wire 11 and the middle layer round wire 12 of the gap steel strand 1 is stripped is equal to the axial length of the convex hammer head.

[0112] The diameters of the first center hole 22 and the second center hole 33 are smaller than the diameter of the gap-type steel strand 1 and larger than the diameter of the center layer round wire 13 .

[0113] After the center layer round wire 13 of the gap-type steel strand 1 is stripped of the outer layer round wire 11 and the middle layer profile wire 12 and passes through the first center hole 22, the outer layer round wire 11 and the middle layer profile wire 12 are abutted against the first center hole 22, ensuring that the center layer round wire 13 does not move significantly when the tensioning tool pre-stresses the center layer round wire 13, and enabling the convex hammer head 31 and the concave hammer head 23 to be more tightly combined into a smooth whole.

[0114] The concave hammer head 23 has a U-shaped structure at one end close to the wire clamp 2 , with the opening of the U-shaped structure facing the wire clamp 2 . A steel sleeve 21 is fixedly installed in the concave portion of the opening of the U-shaped structure, and the steel sleeve 21 is sleeved on the outside of the outer round wire 11 .

[0115] An anchoring fixture embedding groove 32 is provided on the upper and lower edges of the hollow part of the convex hammer head 31 . The anchoring fixture embedding groove 32 is close to the second center hole 33 , and the anchoring fixture is assembled in the anchoring fixture embedding groove 32 .

[0116] As shown in Figure 7, the anchoring clamp includes an upper clamp 41 and a lower clamp 42. The upper clamp 41 and the lower clamp 42 are both wedge-shaped structures. The upper clamp 41 is clamped with the anchoring clamp embedded groove 32 set at the upper edge, and the lower clamp 42 is clamped with the anchoring clamp embedded groove 32 set at the lower edge. After clamping, the wedge-shaped structures of the upper clamp 41 and the lower clamp 42 are opposite to each other at the side, forming a space for the center layer circular wire 13 to pass through, which can be called the third center hole. The center layer circular wire 13 is clamped between the upper clamp 41 and the lower clamp 42.

[0117] When the center layer round wire 13 of the gap-type steel strand 1 is clamped by using the anchoring clamp assembled in the integral hammer head 3, as shown in Figure 8, the gap-type steel strand 1 is stripped to obtain the center layer round wire 13, and the gap-type steel strand 1 is inserted into the steel pipe sleeve of the concave hammer head 23. The outer layer round wire 11 and the middle layer round wire 12 are against the first center hole 22 of the concave hammer head 23, and the center layer round wire 13 passes through the first and second center holes in turn and enters the second center hole 33. Then, the upper clamp 41 and the lower clamp 42 of the anchoring clamp are used to clamp the prestressed center layer round wire 13.

[0118] After the center layer round wire 13 is prestressed and clamped, the tensile stress generated under the vertical impact load must first offset the compressive stress of the outer and middle layer profile wires 12, thereby reducing the tensile stress of the outer and middle layer profile wires 12 of the steel strand, increasing the bending stiffness of the gap-type steel strand 1 and achieving better anti-vibration effect.

[0119] Unlike the traditional vibration damping hammer connection method of crimping the steel strand and hammer head, the prestressed vibration damping hammer is connected through the coupling between the gap-type steel strand 1 and the assembled integral hammer head 3 (i.e., the anchoring fixture inside the assembled integral hammer head 3 clamps the prestressed center layer round wire 13 of the gap-type steel strand 1). The built-in anchoring fixture of the assembled integral hammer head 3 is used to clamp the prestressed center layer round wire 13, thereby achieving the purpose of increasing the steel strand stiffness; at the same time, the anchoring fixture clamps the prestressed center layer round wire 13, so that the assembled integral hammer head 3 with the built-in anchoring fixture is fixed to both ends of the gap-type steel strand 1.

[0120] Example 2

[0121] The present application provides a method for determining the prestress of a steel strand of a vibration damper hammer, which is used to provide a method for determining the value of the prestress of a prestressed vibration damper hammer in Example 1. As shown in FIG9 , the method for determining the prestress of a steel strand of a vibration damper hammer may include the following steps:

[0122] S1. Perform a dynamic test on the anti-vibration hammer steel strand without prestressing to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load.

[0123] S2. Perform a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load.

[0124] S3. Based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load, the value of the prestress is adjusted to obtain the target stress of the anti-vibration hammer steel strand.

[0125] The anti-vibration hammer steel strand is the gap-type steel strand of the anti-vibration hammer in Example 1.

[0126] Among them, the dynamic tests of the anti-vibration hammer steel strands before and after prestressing can be carried out by separately carrying out dynamic tests on the same anti-vibration hammer steel strand before and after prestressing, or by selecting two anti-vibration hammer steel strands of the same specification to carry out dynamic tests before and after prestressing.

[0127] In step S1, a dynamic test is performed on the vibration damper steel strand without prestressing to obtain the first dynamic bending stiffness of the vibration damper steel strand under impact load, specifically including:

[0128] S11. The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand.

[0129] Specifically, the strain gauge is used to obtain the weight of the weight at the critical yield point of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand at this time, which is recorded as the maximum deflection.

[0130] In some embodiments, a dynamic test model as shown in Figure 10 is used to obtain the maximum deflection of the anti-vibration hammer steel strand at the critical yield point. The test model includes: a strain gauge, an acceleration sensor and a weight. The anti-vibration hammer steel strand clamp 2 is held in the test model, the strain gauge is pasted at the position of the anti-vibration hammer steel strand connection clamp 2, the acceleration sensor is connected to one end of the anti-vibration hammer steel strand connected to the hammer head, and the weight is connected to one end of the anti-vibration hammer steel strand connected to the hammer head. The weight of the weight is added according to the test requirements. In this embodiment, the weight of the weight is gradually increased at one end of the anti-vibration hammer steel strand connected to the hammer head, and the strain gauge is used to obtain the critical yield point of the anti-vibration hammer steel strand, and then the maximum deflection is obtained.

[0131] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight and the maximum deflection combined with the calculation formula of the static bending stiffness.

[0132] The calculation formula of the static bending stiffness of the anti-vibration hammer steel strand is obtained through the deflection curve equation. The deflection curve equation of the anti-vibration hammer steel strand is as follows:

[0133] Where h(x) represents the deflection of the anti-vibration hammer strand at position x, x represents the position on the anti-vibration hammer strand, is 0 at the midpoint of the anti-vibration hammer strand (i.e., where the anti-vibration hammer strand connects to the wire clamp), and is l at the connection between the anti-vibration hammer strand and the hammer head; k represents the static bending stiffness of the anti-vibration hammer strand; F represents the load on the free end of the anti-vibration hammer strand; and l represents the distance from the midpoint of the anti-vibration hammer strand to the connection between the anti-vibration hammer strand and the hammer head. According to this formula, the deflection at the connection between the anti-vibration hammer strand and the hammer head is the largest. The maximum deflection is calculated as follows:

[0134] The calculation formula of the static bending stiffness of the anti-vibration hammer steel strand is obtained by conversion using this formula. The calculation formula of the static bending stiffness is as follows:

[0135] Wherein, k represents the static bending stiffness of the anti-vibration hammer steel strand; F represents the load at the free end of the anti-vibration hammer steel strand, that is, the weight of the weight connected to the anti-vibration hammer steel strand; l represents the distance from the midpoint of the anti-vibration hammer steel strand to the connection between the anti-vibration hammer steel strand and the hammer head; h ... max Indicates the maximum deflection.

[0136] S12. Obtain the damping ratio of the anti-vibration hammer steel strand by applying an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration.

[0137] Specifically, an impact load is applied to one end of the anti-vibration hammer steel strand connected to the hammer head to obtain the vibration attenuation curve of the anti-vibration hammer steel strand. A load is applied to one end of the anti-vibration hammer steel strand connected to the hammer head to generate a certain initial displacement, and then unloaded to allow the anti-vibration hammer steel strand to generate free attenuation vibration. The vibration attenuation curve of the attenuation vibration generated by the anti-vibration hammer steel strand after unloading is recorded, as shown in Figure 11, where TD represents a vibration cycle, u1 represents the first vibration cycle, and u i represents the i-th vibration period, u i+1 Indicates the i+1th vibration cycle. According to the amplitude values ​​of two different vibration cycles in the vibration attenuation curve, combined with the calculation formula of the damping ratio, the damping ratio of the anti-vibration hammer steel strand is obtained. The calculation formula of the damping ratio is as follows:

[0138] Where, ζ represents the damping ratio of the anti-vibration hammer steel strand; b represents the interval between two vibration cycles; a represents the ath vibration cycle; u a Indicates the amplitude value of the ath vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand; u a+bIt represents the amplitude value of the a+bth vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand.

[0139] S13. A data acquisition analyzer is used to process the vibration signal of the anti-vibration hammer steel strand after the impact load is applied to obtain the natural frequency of the anti-vibration hammer steel strand.

[0140] Specifically, the natural frequency of the anti-vibration hammer steel strand can be measured using the autospectral analysis method. The test steps are as follows: place the acceleration sensor at one end of the anti-vibration hammer steel strand, connect the output signal to the vibration test channel, turn on the test instrument power, enter the DAS2003 data acquisition and analysis software, set various operating parameters, select the single frequency response analysis function, and obtain the natural frequency of the anti-vibration hammer steel strand.

[0141] S14. Using the static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand when subjected to impact load, combined with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand, the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load is obtained.

[0142] Specifically, S141, using the mass, damping ratio and natural frequency of the anti-vibration hammer steel strand, combined with the damping calculation formula, calculate the damping of the anti-vibration hammer steel strand; the damping calculation formula of the anti-vibration hammer steel strand is as follows: c = 2mw n ζ (5)

[0143] Where, c represents the damping of the anti-vibration hammer steel strand; ζ represents the damping ratio of the anti-vibration hammer steel strand; w n represents the natural frequency of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand.

[0144] S142. Calculate the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load using the static bending stiffness, damping, and excitation frequency of the anti-vibration hammer steel strand when subjected to impact load, combined with the dynamic bending stiffness calculation formula.

[0145] Specifically, the calculation formula of dynamic bending stiffness is as follows:

[0146] Among them, k d represents the dynamic bending stiffness of the anti-vibration hammer steel strand, k represents the static bending stiffness of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand; ω represents the excitation frequency of the anti-vibration hammer steel strand, and the excitation frequency under different impact loads is collected using the excitation equipment; c represents the damping of the anti-vibration hammer steel strand, f is the impact force, that is, the impact load on the anti-vibration hammer steel strand; y represents the displacement response of the anti-vibration hammer steel strand when it is subjected to the impact load, that is, the displacement of the anti-vibration hammer steel strand close to the hammer head end; j refers to the expression of the imaginary part of the dynamic bending stiffness of the anti-vibration hammer steel strand.

[0147] From the calculation formula of dynamic bending stiffness, it can be seen that dynamic bending stiffness is related to the excitation frequency. Dynamic bending stiffness will change with the excitation frequency, rather than being a fixed value. Transforming this calculation, the calculation formula of dynamic bending stiffness after transformation is as follows:

[0148] Among them, k d ω represents the dynamic bending stiffness of the anti-vibration hammer strand, k represents the static bending stiffness of the anti-vibration hammer strand, m represents the mass of the anti-vibration hammer strand, ω represents the excitation frequency of the anti-vibration hammer strand, and c represents the damping of the anti-vibration hammer strand. When the excitation frequency is 0, the dynamic bending stiffness is equal to the static bending stiffness, so the static stiffness is a special case of the dynamic stiffness.

[0149] It can be seen from the calculation formula that the value of dynamic bending stiffness is related not only to the static bending stiffness and excitation frequency of the anti-vibration hammer steel strand, but also to the mass and damping of the anti-vibration hammer steel strand. Therefore, when the dynamic bending stiffness of the anti-vibration hammer is insufficient in a certain frequency band and needs to be optimized, targeted optimization can be carried out by increasing the static bending stiffness, adjusting the mass, increasing the damping, changing the excitation frequency, etc., thereby improving the dynamic bending stiffness.

[0150] In step S2, a dynamic test is performed on the pre-stressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load.

[0151] The second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand under the impact load is obtained by using the method of obtaining the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load in step S1.

[0152] That is, the static bending stiffness of the prestressed anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the prestressed anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand;

[0153] The damping ratio of the prestressed anti-vibration hammer steel strand is obtained by applying an impact load to one end of the prestressed anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration.

[0154] The vibration signal of the anti-vibration hammer steel strand after the impact load is applied is processed by a data acquisition and analysis instrument to obtain the natural frequency of the anti-vibration hammer steel strand after prestressing.

[0155] The second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand under impact load is obtained by using the static bending stiffness, damping ratio, natural frequency and excitation frequency of the prestressed anti-vibration hammer steel strand when subjected to impact load, combined with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand.

[0156] In step S3, based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load, the value of the prestress is adjusted to obtain the target stress of the anti-vibration hammer steel strand.

[0157] Specifically, as shown in FIG12 , if the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the same impact load is within a preset stiffness ratio range, the prestress value is used as the target stress of the anti-vibration hammer steel strand;

[0158] If under the same impact load, the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand is not within the preset stiffness ratio range, the prestress is adjusted and the second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand is recalculated until the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness is within the stiffness ratio range. The prestress value at this time is used as the target stress of the anti-vibration hammer steel strand.

[0159] The stiffness ratio range in this embodiment is 10%≤λ≤30%, where λ represents the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand. The applied tension in Figure 12 is the prestress mentioned in this embodiment, and the prestress value is the target stress.

[0160] Since the anti-vibration hammer steel strand will lose part of the prestress due to shrinkage after prestressing the anti-vibration hammer steel strand, when using the tensioning tool to prestress the anti-vibration hammer steel strand, the target stress can be increased by 2%-5%, thereby reducing the impact of the shrinkage loss of the anti-vibration hammer steel strand.

[0161] The method provided in this application can be used to test the dynamic bending stiffness and damping coefficient of the anti-vibration hammer steel strand under impact load, thereby realizing the dynamic characteristic test of the anti-vibration hammer steel strand under large impact load and the selection of prestressing of the anti-vibration hammer steel strand.

[0162] Example 3

[0163] Based on the same inventive concept, the present application further provides a system for determining the prestress of a steel strand of a vibration damper hammer, which is used to provide a system for determining the value of the prestress of a prestressed vibration damper hammer in Example 1, as shown in FIG13 , comprising:

[0164] The first dynamic bending stiffness determination module is used to perform dynamic testing on the vibration damper steel strand without prestressing to obtain the first dynamic bending stiffness of the vibration damper steel strand under impact load;

[0165] Second dynamic bending stiffness determination module: used to perform dynamic testing on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load;

[0166] Target stress determination module: used to adjust the prestress value to obtain the target stress of the anti-vibration hammer steel strand based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load;

[0167] Among them, the anti-vibration hammer steel strand is the gap-type steel strand of the anti-vibration hammer in Example 1.

[0168] The target stress determination module is specifically used to:

[0169] If the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the same impact load is within the preset stiffness ratio range, the prestress value is used as the target stress of the anti-vibration hammer steel strand;

[0170] If under the same impact load, the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand is not within the preset stiffness ratio range, the prestress is adjusted and the second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand is recalculated until the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness is within the stiffness ratio range. The prestress value at this time is used as the target stress of the anti-vibration hammer steel strand.

[0171] The first dynamic bending stiffness determination module is specifically used to:

[0172] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand.

[0173] The damping ratio of the anti-vibration hammer steel strand is obtained by applying an impact load to the end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration.

[0174] The vibration signal of the anti-vibration hammer steel strand after the impact load is applied is processed by a data acquisition and analysis instrument to obtain the natural frequency of the anti-vibration hammer steel strand;

[0175] The first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load is obtained by using the static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand when subjected to impact load, combined with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand.

[0176] The first dynamic bending stiffness determination module obtains the static bending stiffness of the anti-vibration hammer steel strand by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand, including:

[0177] Use the strain gauge to obtain the weight of the weight at the critical yield point of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand at this time, which is recorded as the maximum deflection;

[0178] The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight and the maximum deflection combined with the calculation formula of the static bending stiffness.

[0179] The calculation formula of static bending stiffness in the first dynamic bending stiffness determination module is as follows:

[0180] Wherein, k represents the static bending stiffness of the anti-vibration hammer steel strand; F represents the load at the free end of the anti-vibration hammer steel strand, that is, the weight of the weight connected to the anti-vibration hammer steel strand; l represents the distance from the midpoint of the anti-vibration hammer steel strand to the connection between the anti-vibration hammer steel strand and the hammer head; h ... max Indicates the maximum deflection.

[0181] The first dynamic bending stiffness determination module obtains the damping ratio of the anti-vibration hammer steel strand by applying an impact load to the end of the anti-vibration hammer steel strand connected to the hammer head, which generates attenuated vibration. The module includes:

[0182] Apply an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to obtain a vibration attenuation curve of the anti-vibration hammer steel strand;

[0183] According to the amplitude values ​​of two different vibration periods in the vibration attenuation curve and combined with the calculation formula of the damping ratio, the damping ratio of the anti-vibration hammer steel strand is obtained.

[0184] The calculation formula of the damping ratio in the first dynamic bending stiffness determination module is as follows:

[0185] Where, ζ represents the damping ratio of the anti-vibration hammer steel strand; b represents the interval between two vibration cycles; a represents the ath vibration cycle; u a Indicates the amplitude value of the ath vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand; u a+b It represents the amplitude value of the a+bth vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand.

[0186] The first dynamic bending stiffness determination module uses the static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand under impact load, combined with the dynamic bending stiffness calculation formula of the anti-vibration hammer steel strand, to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load, including:

[0187] The damping of the anti-vibration hammer steel strand is calculated by using the mass, damping ratio and natural frequency of the anti-vibration hammer steel strand and combining the damping calculation formula.

[0188] The first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load is calculated by using the static bending stiffness, damping and excitation frequency of the anti-vibration hammer steel strand when subjected to impact load, combined with the dynamic bending stiffness calculation formula.

[0189] The calculation formula of the dynamic bending stiffness in the first dynamic bending stiffness determination module is:

[0190] Among them, k d represents the dynamic bending stiffness of the anti-vibration hammer steel strand, k represents the static bending stiffness of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand; ω represents the excitation frequency of the anti-vibration hammer steel strand; c represents the damping of the anti-vibration hammer steel strand.

[0191] Example 4:

[0192] Based on the same inventive concept, the present application also provides a computer device, which includes a processor and a memory, the memory being used to store a computer program, the computer program including program instructions, and the processor being used to execute the program instructions stored in a computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in a computer storage medium to implement a corresponding method flow or corresponding function, so as to implement the steps of a method for determining the prestressing of an anti-vibration hammer steel strand in the above embodiment.

[0193] Example 5:

[0194] Based on the same inventive concept, the present application also provides a storage medium, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of a method for determining the prestressing of an anti-vibration hammer steel strand in the above embodiment.

[0195] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0196] The present application is described with reference to the flow chart and / or block diagram of the method, device (system), and computer program product according to the embodiment of the present application. It should be understood that each flow process and / or box in the flow chart and / or block diagram and the combination of the flow process and / or box in the flow chart and / or block diagram can be realized by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processing machine or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for realizing the function specified in one flow chart flow or multiple flows and / or one box or multiple boxes of the block diagram.

[0197] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0198] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0199] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit its scope of protection. Although the present application has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading this application, those skilled in the art may still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims of the application. Industrial Applicability

[0200] The present application provides a prestressed anti-vibration hammer, comprising: a gap-type steel strand, an assembled integral hammer head and an anchoring clamp; the gap-type steel strand comprises a center layer round wire, an intermediate layer profile wire and an outer layer round wire from the inside to the outside; a gap is set between the center layer round wire and the intermediate layer profile wire, the gap is filled with grease, and the lengths of the intermediate layer profile wire and the outer layer round wire are shorter than the center layer round wire; the intermediate layer profile wire is an arch structure; an assembled integral hammer head is connected to each end of the center layer round wire, and the middle position of each assembled integral hammer head away from one end of the center layer round wire is a hollow part, and the anchoring clamp is assembled in the hollow part; the anchoring clamp is used to prestress the target by using an external tensioning tool The center layer of circular wire is clamped after the force is applied; in this application, after the target stress is pre-applied to the center layer of circular wire, the outer layer of circular wire and the middle layer of profile wire are compressed, and the tensile stress generated under the action of the vertical impact load must first offset the compressive stress of the outer layer and middle layer of profile wire, thereby reducing the tensile stress of the outer layer and middle layer of profile wire of the steel strand, increasing the bending stiffness of the gap-type steel strand, and achieving better vibration isolation effect; wherein, the middle layer of profile wire forms an arch structure, which increases the moment of inertia about the center of circle, and changes the contact between the strands from line to surface contact, so that the force between the strands is more uniform, and there will be no stress concentration like when the circular wires are in contact, thereby enhancing the bending stiffness. Furthermore, a prestressed anti-vibration hammer of the present application is provided with a gap between the center layer round wire and the middle layer profile wire, and the gap is filled with grease. This structural measure is used to reduce the friction resistance between the center layer round wire and the middle layer profile wire, facilitate the application of prestress to the center layer round wire, reduce the wear between the center layer round wire and the middle layer profile wire, reduce the probability of strand breakage, and extend the life of the gap-type steel strand. Different from the traditional anti-vibration hammer steel strand and hammer head crimping connection method, the prestressed anti-vibration hammer is connected by the coupling between the gap-type steel strand and the assembled integral hammer head (i.e., the center layer round wire of the prestressed interstitial steel strand is clamped by the anchoring clamp inside the assembled integral hammer head). The prestressed center layer round wire is clamped by the built-in anchoring clamp of the assembled integral hammer head, thereby achieving the purpose of increasing the stiffness of the steel strand; at the same time, the prestressed center layer round wire is clamped by the anchoring clamp, so that the assembled integral hammer head of the built-in anchoring clamp is fixed to both ends of the interstitial steel strand. The invention discloses a method and system for determining the prestress of an anti-vibration hammer steel strand, comprising performing a dynamic test on an anti-vibration hammer steel strand that is not prestressed to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under an impact load; performing a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under an impact load; and adjusting the value of the prestress based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under an impact load to obtain the target stress of the anti-vibration hammer steel strand, thereby realizing the dynamic characteristic test of the anti-vibration hammer steel strand under a large impact load and the selection of the prestress of the steel strand.

Claims

1. A prestressed anti-vibration hammer, comprising: Gap-type steel strand (1), an assembled integral hammer head (3) and an anchoring fixture; The gap-shaped steel strand (1) comprises, from the inside to the outside, a center layer round wire (13), a middle layer shaped wire (12) and an outer layer round wire (11); a gap (14) is arranged between the center layer round wire (13) and the middle layer shaped wire (12), and the gap (14) is filled with grease; and the lengths of the middle layer shaped wire (12) and the outer layer round wire (11) are shorter than those of the center layer round wire (13); and the middle layer shaped wire (12) is an arch structure; The two ends of the central layer round wire (13) are respectively connected to an assembled integral hammer head (3), and the middle position of each assembled integral hammer head (3) away from one end of the central layer round wire (13) is a hollow part, and the anchoring clamp is assembled in the hollow part; The anchoring clamp is used to clamp the center layer round wire (13) after the target stress is pre-applied by an external tensioning tool; the gap-shaped steel strand (1) and the assembled integral hammer head (3) are coupled and connected through the center layer round wire (13) after the target stress is pre-applied.

2. A prestressed anti-vibration hammer according to claim 1, wherein: The end of the assembled integral hammer head (3) close to the center layer circular line (13) is provided with a center hole; The two ends of the center layer round wire (13) respectively pass through the center holes of the assembled integral hammer heads (3) at one end thereof, and the anchoring fixture is clamped on the center layer round wire (13) that has passed through the center hole and has been pre-stressed with a target stress; The gap-shaped steel strand (1) is coupled and connected with an assembled integral hammer head (3) with an anchoring clamp provided therein, through a center layer round wire (13) passing through a center hole and clamped by an anchoring clamp.

3. A prestressed anti-vibration hammer according to claim 2, wherein: The anti-vibration hammer also includes a wire clamp (2), one end of which is clamped in the middle of the outer round wire (11) and the other end is sleeved on the external conductor; the assembled integral hammer head (3) is symmetrically distributed on both sides of the wire clamp (2).

4. A prestressed anti-vibration hammer according to claim 3, wherein: The assembled integral hammer head (3) comprises a concave hammer head (23) and a convex hammer head (31), wherein the concave hammer head (23) is concave inwardly at one end facing away from the line clamp (2) and is closely attached to the convex hammer head (31) and protrudes outwardly; the convex hammer head (31) is open and hollow at one end facing away from the concave hammer head (23), and the opening direction faces away from the concave hammer head (23), and the anchoring fixture is assembled in the hollow part of the convex hammer head (31); The center hole comprises a first center hole (22) opened in the concave hammer head and a second center hole (31) opened in the convex hammer head. A second center hole (33) is provided; the center layer circular wire (13) passes through the first center hole (22) and the second center hole (33) in sequence.

5. A prestressed anti-vibration hammer according to claim 4, wherein: The diameters of the first center hole (22) and the second center hole (33) are smaller than the diameter of the gap-shaped steel strand (1) and larger than the diameter of the center layer round wire (13).

6. A prestressed anti-vibration hammer according to claim 4, wherein: The concave hammer head (23) has a U-shaped structure at one end close to the wire clamp (2), the opening of the U-shaped structure faces the wire clamp, a steel sleeve (21) is fixedly installed in the concave part of the opening of the U-shaped structure, and the steel sleeve (21) is sleeved on the outside of the outer round wire (11).

7. A prestressed anti-vibration hammer according to claim 4, wherein: An anchoring clamp embedding groove (32) is respectively arranged at the upper and lower edges of the hollow part of the convex hammer head (31), the anchoring clamp embedding groove (32) is closely attached to the second center hole (33), and the anchoring clamp is assembled in the anchoring clamp embedding groove (32).

8. A prestressed anti-vibration hammer according to claim 7, wherein: The anchoring clamp comprises an upper clamp (41) and a lower clamp (42), both of which are wedge-shaped structures. The upper clamp (41) is clamped with an anchoring clamp embedding groove (32) arranged at the upper edge, and the lower clamp (42) is clamped with an anchoring clamp embedding groove (32) arranged at the lower edge. After clamping, the wedge-shaped structures of the upper clamp (41) and the lower clamp (42) are opposite to each other at the side, and the center layer circular wire (13) is clamped between the upper clamp (41) and the lower clamp (42).

9. A prestressed anti-vibration hammer according to claim 1, wherein: The intermediate layer profile (12) comprises: A plurality of profiled wires, the cross section of which is a quadrilateral that is wide at the top and narrow at the bottom, are twisted and extruded in the same direction around a central layer round wire (13) to form an arch structure.

10. A method for determining the prestress of a vibration-proof hammer steel strand, comprising: Performing a dynamic test on a vibration-proof hammer steel strand without prestressing to obtain the first dynamic bending stiffness of the vibration-proof hammer steel strand under impact load; Performing a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load; Based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load, the value of the prestress is adjusted to obtain the target stress of the anti-vibration hammer steel strand; Wherein, the anti-vibration hammer steel strand is the gap-type steel strand of the anti-vibration hammer as described in claim 1.

11. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 10, wherein: The method of adjusting the value of the prestress based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load to obtain the target stress of the anti-vibration hammer steel strand comprises: If the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the same impact load is within the preset stiffness ratio range, the value of the prestress is taken as the target stress of the anti-vibration hammer steel strand; If under the same impact load, the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand is not within the preset stiffness ratio range, the prestress is adjusted and the second dynamic bending stiffness of the prestressed anti-vibration hammer steel strand is recalculated until the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness is within the stiffness ratio range, and the prestress value at this time is used as the target stress of the anti-vibration hammer steel strand.

12. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 10, wherein: The method of performing a dynamic test on the vibration-proof hammer steel strand without prestressing to obtain the first dynamic bending stiffness of the vibration-proof hammer steel strand under impact load includes: The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand. The damping ratio of the anti-vibration hammer steel strand is obtained by applying an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration; The vibration signal of the anti-vibration hammer steel strand after the impact load is applied is processed by a data acquisition analyzer to obtain the natural frequency of the anti-vibration hammer steel strand; The static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand under impact load are used in combination with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load.

13. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 12, wherein: The method of obtaining the static bending stiffness of the anti-vibration hammer steel strand by using the weight of the weight applied to one end of the anti-vibration hammer steel strand and the deflection of the anti-vibration hammer steel strand comprises: The weight of the weight and the deflection of the anti-vibration hammer steel strand at the critical point of yield of the anti-vibration hammer steel strand are obtained by using the strain gauge, which is recorded as the maximum deflection; The static bending stiffness of the anti-vibration hammer steel strand is obtained by using the weight of the weight and the maximum deflection combined with the calculation formula of the static bending stiffness.

14. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 13, wherein: The calculation formula of the static bending stiffness is: Among them, k represents the static bending stiffness of the anti-vibration hammer steel strand; F represents the load on the free end of the anti-vibration hammer steel strand, that is, the weight of the weight connected to the anti-vibration hammer steel strand; l represents the distance from the midpoint of the anti-vibration hammer steel strand to the connection between the anti-vibration hammer steel strand and the hammer head; h max Indicates the maximum deflection.

15. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 12, wherein: The damping ratio of the anti-vibration hammer steel strand is obtained by applying an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to generate attenuated vibration, including: Apply an impact load to one end of the anti-vibration hammer steel strand connected to the hammer head to obtain a vibration attenuation curve of the anti-vibration hammer steel strand generated by attenuated vibration; According to the amplitude values ​​of two different vibration periods in the vibration attenuation curve and the calculation formula of the damping ratio, the damping ratio of the anti-vibration hammer steel strand is obtained.

16. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 15, wherein: The damping ratio is calculated as: Where, ζ represents the damping ratio of the anti-vibration hammer steel strand; b represents the interval period value between two vibration cycles; a represents the ath vibration cycle; u a It represents the amplitude value of the ath vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand; u a+b It represents the amplitude value of the a+bth vibration cycle in the vibration attenuation curve of the anti-vibration hammer steel strand.

17. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 12, wherein: The static bending stiffness, damping ratio, natural frequency and excitation frequency of the anti-vibration hammer steel strand under impact load are used in combination with the calculation formula of the dynamic bending stiffness of the anti-vibration hammer steel strand to obtain the first dynamic bending stiffness of the anti-vibration hammer steel strand under impact load, including: The damping of the anti-vibration hammer steel strand is calculated by using the mass, damping ratio and natural frequency of the anti-vibration hammer steel strand and combining the damping calculation formula. The static bending stiffness, damping and excitation frequency of the anti-vibration hammer steel strand under impact load are used in combination with the dynamic bending stiffness calculation formula to calculate the first dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load.

18. A method for determining prestressing of a vibration-proof hammer steel strand according to claim 17, wherein: The dynamic bending stiffness calculation formula is: Among them, k d represents the dynamic bending stiffness of the anti-vibration hammer steel strand, k represents the static bending stiffness of the anti-vibration hammer steel strand; m represents the mass of the anti-vibration hammer steel strand; ω represents the excitation frequency of the anti-vibration hammer steel strand; c represents the damping of the anti-vibration hammer steel strand.

19. A system for determining prestress of a vibration-proof hammer steel strand, comprising: The first dynamic bending stiffness determination module is used to perform a dynamic test on the vibration-proof hammer steel strand without prestressing to obtain the first dynamic bending stiffness of the vibration-proof hammer steel strand under impact load; The second dynamic bending stiffness determination module is used to perform a dynamic test on the prestressed anti-vibration hammer steel strand to obtain the second dynamic bending stiffness of the anti-vibration hammer steel strand under impact load; A target stress determination module is used to adjust the value of the prestress to obtain the target stress of the anti-vibration hammer steel strand based on the ratio of the first dynamic bending stiffness to the second dynamic bending stiffness of the anti-vibration hammer steel strand under the impact load; Wherein, the anti-vibration hammer steel strand is the gap-type steel strand of the anti-vibration hammer as described in claim 1.

20. A computer device comprising: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, a method for determining the prestressing of a vibration-damping steel strand as claimed in any one of claims 10 to 18 is implemented.

21. A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method for determining the prestressing of a vibration-proof hammer steel strand according to any one of claims 10 to 18 is implemented.

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