A vibration reduction device under rails and a vibration reduction structure under rails in shield tunnels

Abstract

This invention relates to the field of high-speed railway vibration and noise control technology, specifically to a track-mounted vibration reduction device and a shield tunnel track-mounted vibration reduction structure. The device includes a sealed housing containing multiple resonant metal plates arranged at intervals. Each resonant metal plate has a perforation array. The sealed housing is filled with a viscous damping medium, which completely submerges the perforation array. When the track-mounted vibration reduction device of this invention is in operation, the resonant metal plates undergo bending vibration, transferring the vibration of the track structure to the resonant metal plates. The vibration of the resonant metal plates is dissipated by the frictional energy dissipated by the viscous damping medium through the perforations. Through the coupling effect of the bending vibration of the resonant metal plates and the flow of the damping medium through the perforations, the vertical vibration kinetic energy of the track is converted into structural strain energy and fluid frictional heat energy, thereby suppressing the transmission of vibration energy in the 30-80Hz frequency band.

Description

Technical Field

[0001] This invention relates to the field of vibration and noise control technology for high-speed railways, specifically to a track-mounted vibration reduction device and a track-mounted vibration reduction structure for shield tunnels. Background Technology

[0002] With the rapid development of high-speed railways and the increasing demands of people for living and riding environments, the vibration and noise generated by high-speed railway operation has become an important part of vibration reduction design in the field of high-speed railway structure. At present, in addition to rail vibration absorbers, the vibration control measures of the entire high-speed railway structure are mainly as follows: (1) Vibration damping fasteners: They absorb high-frequency vibration energy by using elastic deformation, but they amplify low-frequency vibration, which is not conducive to driving safety and is difficult to apply to high-speed railways. In addition, there is a time-varying effect of stiffness, and the aging of rubber leads to an annual stiffness attenuation rate of ≥5%, which affects the maintenance of track geometry; (2) Elastic sleepers: Polyurethane elastic pads are set at the bottom of the sleepers to reduce the transmission of medium-frequency vibration through the mass-spring system. However, the replacement of elastic pads requires the removal of sleeper bolts, which increases the maintenance window time by 30%, resulting in poor maintenance accessibility. Furthermore, they cannot reduce low-frequency vibration, resulting in insufficient frequency band coverage; (3) Steel spring floating plate: Steel spring vibration isolators with a frequency of 10-20Hz are used to support the concrete floating plate to achieve low-frequency vibration isolation. However, there is a low-frequency amplification effect. The vibration acceleration is amplified by 2-3 times in the 10-20Hz frequency band. Moreover, the construction cost is high, the cost per kilometer is high, the construction period is long, and there is also a waterproofing hazard. The water seepage rate at the connection between the spring sleeve and the tunnel bottom plate is >3%. (4) Track wave resistance block: The band gap characteristics of phononic crystal are used to suppress vibration propagation. However, the band gap frequency is fixed (design center frequency ±5Hz), which cannot adapt to the wheel-rail excitation frequency shift. The unit structure size is ≥200mm, which conflicts with the shield segment bolts. The manufacturing cost is 4-6 times that of traditional measures. Summary of the Invention

[0003] The purpose of this invention is to provide a track-under vibration reduction device and a track-under vibration reduction structure for shield tunnels, which can at least solve some of the defects in the prior art.

[0004] To achieve the above objectives, the technical solution of the present invention is an under-rail vibration reduction device, comprising a sealed housing, wherein multiple resonant metal plates are arranged at intervals inside the sealed housing, and each of the resonant metal plates is provided with a hole array, and the sealed housing is filled with a viscous damping medium, wherein the viscous damping medium completely submerges the hole array.

[0005] As one embodiment, the thickness of the multiple resonant metal plates is gradient-distributed, and / or the width of the multiple resonant metal plates is gradient-distributed, and / or the aperture density of the multiple resonant metal plates is gradient-distributed.

[0006] As one embodiment, the thickness of the resonant metal plate is 10~20mm, the width of the resonant metal plate is 0.8~2m, and the aperture density of the resonant metal plate is 0.2~0.6.

[0007] As one implementation method, all holes in the aperture array have the same aperture diameter and spacing; or the aperture diameter and spacing of all holes in the aperture array decrease from the central region to the edge region.

[0008] As one embodiment, the viscous damping medium contains nano-thermal conductive fillers, and the average particle size D50 of the nano-thermal conductive fillers is 40-60 nm, and the volume fraction φ is 0.2-1.6%.

[0009] As one embodiment, the surface of the resonant metal plate is provided with a micro-arc oxide film layer, the thickness of which is 20-30μm and the hardness is ≥HV800.

[0010] As one embodiment, the sealing housing includes a metal shell and a first anchoring plate and a second anchoring plate; the metal shell has a horizontally arranged top surface and a vertically arranged side surface, both of which are open and are sealed by the first anchoring plate and the second anchoring plate respectively.

[0011] The present invention also provides a vibration damping structure under the rail of a shield tunnel, including a rail foundation disposed within the tunnel lining, the rail foundation having a longitudinally extending under-rail cavity, the under-rail vibration damping device described in any of the above claims being disposed within the under-rail cavity, and the sealing shell being fixedly connected to the rail foundation.

[0012] As one implementation method, the track cavity is divided into a central cavity in the middle and side cavities on both sides by a partition. Several track vibration damping devices are arranged longitudinally in the side cavities on both sides.

[0013] As one embodiment, an epoxy resin transition layer is provided between the sealing housing and the track foundation.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) When the track vibration damping device of the present invention is working, the resonant metal plate undergoes bending vibration, which transfers the vibration of the track structure to the resonant metal plate. The vibration of the resonant metal plate is dissipated by the friction energy dissipated by the viscous damping medium through the holes of the resonant metal plate. Through the coupling effect of the bending vibration of the resonant metal plate and the flow of the viscous damping medium through the holes, the vertical vibration kinetic energy of the track is converted into structural strain energy and fluid friction heat energy, thereby suppressing the transmission of vibration energy in the 30-80Hz frequency band.

[0016] (2) The present invention designs multiple resonant metal plates with gradient thickness distribution, and / or gradient length distribution, and / or gradient aperture density distribution, and adjusts the position of the resonance peaks, thereby forming a group of resonance peaks that continuously cover the key vibration frequency band of the wheel-rail system in the range of 30-80Hz, and achieving efficient energy dissipation.

[0017] (3) The track vibration damping device of the present invention has a wide vibration damping frequency band, simple structure, low processing and manufacturing cost, convenient installation, and long service life;

[0018] (4) The present invention sets the vibration reduction device under the track in the cavity space of the foundation under the track of the shield tunnel. The multi-mode vibration of the resonant metal plate realizes the efficient broadband dissipation of the vibration energy of the structure under the track of the shield tunnel, which can reduce the vibration noise generated by the operation of high-speed railway. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the track-mounted vibration damping device provided in an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of a bending energy dissipation plate provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the vibration reduction structure under the shield tunnel rail provided in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the vibration reduction structure under the shield tunnel rail provided in an embodiment of the present invention;

[0024] In the diagram: 1. Metal shell; 2. First anchoring plate; 3. Second anchoring plate; 4. Viscous damping medium; 5. Resonant metal plate; 51. Hole; 6. Tunnel lining; 7. Track foundation; 71. Top plate; 72. Arc-shaped bottom plate; 73. Partition plate; 74. Central cavity; 75. Side cavity; 8. Track slab; 9. Epoxy resin transition layer. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0028] like Figures 1-2 As shown, this embodiment provides a track vibration damping device, including a sealed housing. Multiple resonant metal plates 5 are arranged at intervals within the sealed housing, and each resonant metal plate 5 has a perforation array. The sealed housing is filled with a viscous damping medium 4, which completely submerges the perforation array. When the track vibration damping device of this embodiment is in operation, the multiple resonant metal plates 5 undergo bending vibration, transferring the vibration of the track structure to the resonant metal plates 5. The vibration of the resonant metal plates 5 is dissipated by the frictional energy dissipated by the viscous damping medium 4 through the perforations 51 of the resonant metal plates 5. Through the coupling effect of the bending vibration of the resonant metal plates 5 and the flow of the damping medium through the perforations 51, the vertical vibration kinetic energy of the track is converted into structural strain energy and fluid frictional heat energy, thereby suppressing the transmission of vibration energy in the 30-80Hz frequency band.

[0029] like Figure 1 As shown, the top of each resonant metal plate 5 is connected to the top of the sealed shell, and the bottom is connected to the side or bottom of the sealed shell. The vibration energy of the track foundation 7 is transmitted to the resonant metal plate 5 through the sealed shell, and the resonant metal plate 5 absorbs the vibration energy into the resonant metal plate 5 through resonance.

[0030] In this embodiment, the effective bending mode frequencies of the multiple resonant metal plates 5 are different from each other and are all located between 30 and 80 Hz. The effective bending mode frequency of the resonant metal plate 5 is the first or second order resonant frequency of the resonant metal plate 5, and for plates whose length is much greater than their width (ratio greater than 5), the ratio of the first order resonant frequency to the second order resonant frequency is 1:4.

[0031] Furthermore, the thickness of the multiple resonant metal plates 5 is gradient-distributed, and / or the width of the multiple resonant metal plates 5 is gradient-distributed, and / or the aperture density of the multiple resonant metal plates 5 is gradient-distributed. The length of the resonant metal plate 5 is its dimension along the track length direction, and its width is its dimension from top to bottom; the length of the resonant metal plate 5 is determined by the length of the sealing shell; the aperture density ρ of the resonant metal plate 5 = the total area of ​​all holes 51 / the area of ​​the resonant metal plate 5. By designing the thickness, width, and / or aperture density of the multiple resonant metal plates 5 to be gradient-distributed, and / or the position of the resonance peaks can be controlled, thereby enabling the multiple resonant metal plates 5 to form a continuous cluster of resonance peaks covering the key vibration frequency band of the wheel-rail system within the 30-80Hz range, achieving efficient energy dissipation.

[0032] Furthermore, the thickness of the resonant metal plate 5 is 10~20mm, the width of the resonant metal plate 5 is 0.8~2m, and the aperture density of the resonant metal plate 5 is 0.2~0.6, thereby achieving vibration energy capture in the range of 30-80Hz.

[0033] In this embodiment, the effective bending mode frequencies f1, f2…f of the multiple metal plates are... n satisfy:

[0034] ;

[0035] .

[0036] In one embodiment, 15 resonant metal plates 5 are disposed within the sealed housing. Each resonant metal plate 5 has a thickness of 10 mm, a length of 2 m, and a width between 0.7 and 2 m, determined by its installation position, forming a natural bending modal frequency gradient. The frequency distribution is verified using ANSYS modal analysis.

[0037] ;

[0038] Where E = 210 GPa, I is the moment of inertia of the cross section, ρ = 7850 kg / m³, A is the cross-sectional area (width × thickness), and L is the width. The first-order resonant frequencies of the 15 resonant metal plates 5 are between 10-80 Hz, and the effective bending mode frequencies form a continuous vibration reduction band of 30-80 Hz, with frequency intervals all less than 4 Hz.

[0039] Furthermore, all holes 51 in the aperture array have the same diameter and spacing; or the diameter and spacing of all holes in the aperture array decrease from the center region to the edge region. By controlling the diameter and spacing of the aperture array, the Reynolds number Re ≥ 2500 when the viscous damping medium 4 passes through the aperture array, and the turbulent energy dissipation ratio > 65%, the conversion of vibration energy into heat energy is achieved, thereby providing better energy dissipation capacity and improving dynamic vibration reduction efficiency. Figure 2 As shown, the aperture array is located in the central region of the resonant metal plate 5, and the aperture array includes multiple holes 51.

[0040] In some embodiments, all holes 51 in the aperture array have the same diameter and spacing, with the diameter d being 10-20 mm and the spacing s being 3-5 times the diameter. Specifically, the aperture array on the resonant metal plate 5 adopts a rectangular or hexagonal uniformly distributed matrix. For resonant metal plates 5 with an effective bending mode frequency of 20-60 Hz, a spacing of 20 mm can be used; for resonant metal plates 5 with an effective bending mode frequency of 60-80 Hz, a spacing of 10 mm can be used. The total area of ​​the holes 51 in a single resonant metal plate 5 is not less than 1000 mm². 2 However, increasing the area of ​​the hole 51 does not significantly affect the natural frequency of the resonant metal plate 5.

[0041] In other embodiments, the aperture and spacing of all aperture arrays decrease from the central region to the edge region, and the aperture d of the holes 51 are distributed according to an exponential law:

[0042] ;

[0043] Where, d max =20mm, k=0.001mm-1, x is the distance from hole 51 to the center of the board, -500mm≤x≤500mm, and the hole spacing is 60 mm.

[0044] Furthermore, the viscous damping medium 4 fills 75-90% of the volume of the sealed housing, and the immersion depth of the viscous damping medium 4 in the pore array is not less than 15mm, so as to ensure that the viscous damping medium 4 can dissipate more of the vibration of the resonant metal plate 5.

[0045] In the optimized embodiment, the viscous damping medium 4 is supplemented with nano-thermal conductive filler, wherein the average particle size D50 of the nano-thermal conductive filler is 40-60 nm, and the volume fraction φ is 0.2-1.6%. By adding a certain volume fraction of nano-thermal conductive filler to the viscous damping medium 4, the thermal conductivity can be improved, ensuring that the viscosity-temperature coefficient α ≤ 0.0015 / ℃, guaranteeing that the dynamic viscosity fluctuation rate is <10% under the environment of -20℃ to +60℃, suppressing the viscosity decay of the viscous damping medium 4 under cyclic shearing, delaying the degradation of damping performance, and improving the long-term service performance of the device. In this embodiment, the viscous damping medium 4 can be hydraulic oil, etc., and the nano-thermal conductive filler can be nano-alumina particles, nano-boron nitride particles, etc. In one embodiment, the viscous damping medium 4 is methylphenyl silicone oil with a dynamic viscosity μ=46±5cSt (25℃), viscosity-temperature coefficient α=0.0012 / ℃, filling amount V=80% of the sealed housing volume, and nano-alumina particles with an average particle size D50 of 50nm are added, with a volume fraction φ of 0.8% for the nano-alumina particles, so that the performance degradation rate of the device during its 20-year service life is <2%.

[0046] In an optimized embodiment, a micro-arc oxide film layer is formed on the surface of the resonant metal plate 5. The thickness of the micro-arc oxide film layer is 20-30 μm, and the hardness is ≥HV800. By performing micro-arc oxidation treatment on the surface of the resonant metal plate 5, a micro-arc oxide film layer is formed on the surface of the resonant metal plate 5, which can inhibit the corrosion of the viscous damping medium 4 by acidic components, thereby improving the long-term service performance of the device. In one embodiment, the thickness of the micro-arc oxide film layer is 25 μm, the porosity is ≤5%, and the microhardness is HV=850.

[0047] In some embodiments, the sealing housing includes a metal outer shell 1 and a first anchoring plate 2 and a second anchoring plate 3; the metal outer shell 1 has a horizontally arranged top surface and a vertically arranged side surface, both of which are open and sealed by the first anchoring plate 2 and the second anchoring plate 3 respectively. Figure 1 As shown, the metal shell 1 is a trapezoidal structure, which includes an upper rectangular surface, a front trapezoidal surface, a lower rectangular surface, and a rear trapezoidal surface. The upper rectangular surface and the lower rectangular surface are parallel and inclined, and the front trapezoidal surface and the rear trapezoidal surface are parallel. The upper rectangular surface, the front trapezoidal surface, the lower rectangular surface, and the rear trapezoidal surface enclose and form an inclined trapezoidal structure. The horizontally arranged top surface and the vertically arranged side surface are open and sealed by the horizontally arranged first anchoring connecting plate 2 and the vertically arranged second anchoring connecting plate 3, respectively, thus forming a sealed shell. Multiple resonant metal plates 5 are arranged at intervals inside the sealed shell. The resonant metal plates 5 are inclined and parallel to the upper rectangular surface and the lower rectangular surface. The upper and lower ends are connected to the first anchoring connecting plate 2 and the second anchoring connecting plate 3, respectively.

[0048] In this embodiment, the metal shell 1, the resonant metal plate 5, the first anchoring connection plate 2, and the second anchoring connection plate 3 can all be made of Q345B weathering structural steel. The first anchoring connection plate 2 and the second anchoring connection plate 3 are rectangular steel plates, and all four sides extend outside the metal shell 1 to facilitate the arrangement of anchor bolt holes to achieve the connection between the sealed shell and the track foundation 7. The upper and lower rectangular surfaces of the metal shell 1 are made of rectangular steel plates, and the front and rear trapezoidal surfaces are made of U-shaped steel plates spliced ​​together. The openings of the U-shaped steel plates face the outside of the metal shell 1. A resonant metal plate 5 is sandwiched between every two adjacent U-shaped steel plates, and the end of the resonant metal plate 5 is connected to the flanges of the U-shaped steel plates on both sides of it with high-strength friction bolts, and the adjacent U-shaped steel plates are sealed. The upper and lower ends of the resonant metal plate 5 are welded to the first anchoring connection plate 2 and the second anchoring connection plate 3, respectively, and the front and rear ends are connected to the corresponding U-shaped steel plates of the front and rear trapezoidal surfaces of the metal shell 1, respectively. In one embodiment, the first anchoring plate 2 and the second anchoring plate 3 are both 2m long and 12mm thick. The width of the first anchoring plate 2 is 2m, and the height of the second anchoring plate 3 is 1.7m. Ten bolt holes are pre-drilled in each of the length directions (0-200mm and 1800-2000mm) of both the first and second anchoring plates 2 and 3. Ten bolt holes are pre-drilled in each of the width directions (0-200mm and 1800-2000mm) of the first anchoring plate 2, and ten bolt holes are pre-drilled in each of the height directions (0-200mm and 1500-1700mm) of the second anchoring plate 3. The bolt holes are evenly distributed. The U-shaped steel plate is 10mm thick, with a web height of 100mm and a flange height of 150mm. mm; the rectangular steel plate on the upper rectangular surface of the metal shell 1 is 2m long, 0.5m wide, and 10mm thick, and the rectangular steel plate on the lower rectangular surface is 2m long, 2.6m wide, and 10mm thick.

[0049] This embodiment also provides a vibration reduction structure under the track of a shield tunnel, including a track foundation 7 installed within the tunnel lining 6. The track foundation 7 has a longitudinally extending under-track cavity, and the under-track vibration reduction device described above is installed within the under-track cavity. The sealing shell is fixedly connected to the track foundation 7. This embodiment, by installing the under-track vibration reduction device in the under-track cavity within the track foundation 7, absorbs vibration energy into the resonant metal plate 5 through the resonance effect of the resonant metal plate 5. The vibration energy is dissipated by the viscous damping medium 4 through the perforated array on the resonant metal plate 5, achieving a broadband vibration reduction effect. The vibration insertion loss is greater than 3 dB in the frequency range of 30-80Hz. It is also easy to construct, does not require changes to the original shield tunnel construction procedures or structural design, has no adverse impact on train running stability parameters, does not affect the clearance above the track elevation, and does not intrude on the space required for train operation. It is particularly suitable for high-speed railway shield tunnels with a diameter of 12m or greater.

[0050] In the optimized embodiment, the under-rail cavity is divided into a central cavity 74 and side cavities 75 located on both sides by a partition 73. Several under-rail vibration damping devices are arranged longitudinally at intervals within each of the side cavities 75. Specifically, the first anchoring plate 2 and the second anchoring plate 3 of the under-rail vibration damping device are firmly connected to the top and side surfaces of the side cavities 75 respectively using chemical anchors. Since the central cavity 74 is generally used as a pipeline laying or maintenance passage, the integrated arrangement of the under-rail vibration damping devices within the side cavities 75 on both sides of the track foundation 7 fully utilizes the space of the side cavities 75 without affecting pipeline laying or maintenance.

[0051] In this embodiment, the track foundation 7 includes an arc-shaped base plate 72 and a top plate 71. The two ends of the top plate 71 are connected to the two ends of the arc-shaped base plate 72, forming a track cavity. The track cavity is divided into a central cavity 74 and side cavities 75 by two longitudinally extending partitions 73. Several track vibration damping devices are arranged longitudinally at intervals within each side cavity 75. The first anchoring plate 2 and the second anchoring plate 3 are connected to the top plate 71 and the partitions 73, respectively. Specifically, several chemical anchors are connected to the top plate 71 around the perimeter of the first anchoring plate 2, and several chemical anchors are connected to the partitions 73 around the perimeter of the second anchoring plate 3. The diameter of the chemical anchors is... The implantation depth h=150mm; the anchor bolt holes on the first anchoring plate 2 and the second anchoring plate 3 are both located outside the sealed shell.

[0052] The vibration reduction device under the track in this embodiment has a wide vibration reduction bandwidth, simple structure, low processing and manufacturing cost, convenient installation, long service life, and constructs a multi-level energy transfer chain. The track vibration is transferred to the resonant metal plate 5 through the kinetic energy of the chemical anchor bolts. The resonant metal plate 5 undergoes bending vibration and generates bending strain energy. The viscous damping medium 4 dissipates the vibration energy of the metal plate through turbulent friction, thus achieving a wide-band vibration reduction effect.

[0053] Furthermore, along the track direction, the length of a single track-mounted vibration damping device is less than or equal to the unit length of the track foundation 7, the length of the metal shell 1 is less than the unit length of the track foundation 7, and the length of the resonant metal plate 5 is greater than the length of the metal shell 1, with both ends protruding from the metal shell 1 to facilitate connection between the resonant metal plate 5 and the metal shell 1. In one embodiment, the unit length of the track foundation 7 is 2m, the unit length of the track-mounted vibration damping device is equal to or slightly less than 2m; the length of the metal shell 1 is less than 2m, with reserved anchoring positions for easy installation, which can be 1.6m; the length of the resonant metal plate 5 is greater than the length of the metal shell 1, with both ends protruding from the metal shell 1 and fixedly connected to it. The width and height of the track-mounted vibration damping device match the dimensions of the side openings 75 on both sides of the track foundation 7.

[0054] In an optimized embodiment, an epoxy resin transition layer 9 is provided between the sealing shell and the track foundation 7. Specifically, epoxy resin transition layers 9 are provided between the first anchoring plate 2 and the track foundation 7, and between the second anchoring plate 3 and the track foundation 7. The epoxy resin transition layer 9 can significantly improve the bonding strength between the sealing shell and the track foundation 7, making it less prone to relative slippage under shear loads. Simultaneously, the epoxy resin transition layer 9 has a certain elastic modulus (elastic modulus ≥ 15 GPa), which can absorb some energy when subjected to external loads. In one embodiment, the thickness of the epoxy resin transition layer 9 is δ = 2 mm, the elastic modulus is E = 15 GPa, and the loss factor η ≥ 0.05.

[0055] Further, the epoxy resin transition layer 9 comprises the following components by mass percentage: 60%-65% epoxy resin, 25%-30% silica powder, 5%-8% polysulfide rubber, and 4%-6% curing agent. Specifically, the epoxy resin can be epoxy resin E-51, the silica powder has an average particle size D50=15μm, the polysulfide rubber can be polysulfide rubber JLY-155, and the curing agent can be curing agent T31.

[0056] The broadband vibration reduction performance and long-term service stability of the track-mounted vibration reduction device in this embodiment are verified through laboratory testing, numerical simulation, and engineering verification.

[0057] Within the target frequency band of 30-80Hz, the vibration acceleration insertion loss (IL) is ≥3dB, specifically: 35Hz: IL=3.2dB; 52Hz: IL=3.7dB; 73Hz: IL=3.8dB.

[0058] Resonant metal plate 5 mm 5 × 10 6 No cracks were observed in the second fatigue test (load amplitude ±15kN); the annual viscosity decay rate of the hydraulic oil was ≤1.2%.

[0059] The pull-out resistance of the anchoring system is ≥120kN (JGJ 145-2013 standard), and the preload loss rate after 5 years of operation is ≤3%; the shear strength retention rate of the epoxy resin transition layer 9 in the pH=3-11 environment is >95%.

[0060] The construction process of the track-mounted vibration reduction structure in this embodiment is as follows:

[0061] (1) The assembly of the track damping device is completed in the factory, and the viscous damping medium 4 is injected into the sealed shell to a predetermined volume fraction; specifically, the two ends of the resonant metal plate 5 in the width direction are welded and fixed to the first anchoring connection plate 2 and the second anchoring connection plate 3 respectively, and then U-shaped steel plates are spliced ​​at both ends in the length direction of the resonant metal plate 5. The resonant metal plate 5 is sandwiched between adjacent U-shaped steel plates, and the resonant metal plate 5 is tightly connected to the U-shaped steel plates on both sides by high-strength friction bolts to form the front trapezoidal surface and the rear trapezoidal surface of the metal shell. After that, it is fixed, and rectangular steel plates are welded between them to form the lower rectangular surface of the metal shell. Then, hydraulic oil is injected to a predetermined volume fraction, and then rectangular steel plates are welded to form the upper rectangular surface of the metal shell to obtain the sealed shell.

[0062] (2) Roughen the top and side surfaces of the side openings 75 on both sides of the track foundation 7, and drill holes at the locations where the vibration damping devices under the track are installed;

[0063] (3) The first anchoring plate 2 and the second anchoring plate 3 are connected to the top and side surfaces of the side cavity 75 by chemical anchors, so that the track foundation 7 and the track vibration damping device are integrated.

[0064] (4) During normal shield tunnel construction, the track foundation 7 and the overall structure of the track vibration reduction device are hoisted and installed.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vibration reduction structure under the rail of a shield tunnel, characterized in that: The system includes a track foundation installed within the tunnel lining. The track foundation has a longitudinally extending under-track cavity. An under-track vibration damping device is installed within the under-track cavity. The under-track vibration damping device includes a sealed housing, which is fixedly connected to the track foundation. Multiple resonant metal plates are spaced apart within the sealed housing. Each resonant metal plate has a perforated array. The sealed housing is filled with a viscous damping medium, which completely submerges the perforated array. The top of each resonant metal plate is connected to the top of the sealed housing. bottom It is connected to the side or bottom of the sealed housing.

2. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: The thickness of the multiple resonant metal plates is gradient-distributed, and / or the width of the multiple resonant metal plates is gradient-distributed, and / or the aperture density of the multiple resonant metal plates is gradient-distributed.

3. The shield tunnel track-under vibration reduction structure as described in claim 2, characterized in that: The thickness of the resonant metal plate is 10~20mm, the width of the resonant metal plate is 0.8~2m, and the aperture density of the resonant metal plate is 0.2~0.

6.

4. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: All holes in the aperture array have the same diameter and spacing; or the diameter and spacing of all holes in the aperture array decrease from the central region to the edge region.

5. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: The viscous damping medium contains nano-thermal conductive fillers, and the average particle size D50 of the nano-thermal conductive fillers is 40-60 nm, and the volume fraction φ is 0.2-1.6%.

6. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: The surface of the resonant metal plate is provided with a micro-arc oxide film layer, the thickness of which is 20-30μm and the hardness is ≥HV800.

7. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: The sealed housing includes a metal shell and a first anchoring plate and a second anchoring plate; the metal shell has a horizontally arranged top surface and a vertically arranged side surface, both of which are open and are sealed by the first anchoring plate and the second anchoring plate respectively.

8. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: The under-rail cavity is divided into a central cavity and side cavities on both sides by a partition. Several under-rail vibration damping devices are arranged longitudinally in the side cavities on both sides.

9. The shield tunnel track-under vibration reduction structure as described in claim 1, characterized in that: An epoxy resin transition layer is provided between the sealed housing and the track foundation.

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