Novel phonon transistor pile

Abstract

The invention discloses a novel phonon transistor pile, which belongs to the technical field of soil vibration reduction and comprises a pile tip, a pile body and a plurality of ABH-L.R. Combined vibration reduction units. The pile tip is located at the bottom end of the pile body. The ABH-L.R. Combined vibration reduction units are periodically distributed in the pile body from bottom to top along the height of the pile body and connected with the pile body through elastic materials. The ABH-L.R. Combined vibration reduction units are periodically arranged in the pile body, vibration is gathered in the center of the structure through the two-dimensional acoustic black hole plate, energy is dissipated through the energy dissipation characteristic of the constraint damping layer arranged in the center of the two-dimensional acoustic black hole plate and the local resonance effect generated by the L.R. Phononic crystal unit cells, the tubular pile can have the elastic wave band gap characteristic, and the elastic wave band gap vibration reduction effect is achieved. Low-frequency vertical vibration can be effectively filtered, and the influence of the vertical vibration on a building is restrained.

Description

Technical Field

[0001] The invention belongs to the technical field of soil vibration reduction, and in particular relates to a novel phonon transistor pile. Background Art

[0002] Phononic crystal is a new physical concept proposed in the field of condensed matter physics based on the study of photonic crystals. Phononic crystal refers to a periodic composite material or structure composed of two or more media with elastic wave band gap characteristics. When elastic waves propagate in phononic crystals, elastic waves in certain frequency ranges cannot propagate, and the corresponding frequency ranges become band gaps; while elastic waves in other frequency ranges can propagate, and the corresponding frequency ranges become passbands. There are some attempts to apply the vibration reduction and noise reduction of phononic crystal theory in the fields of precision machinery manufacturing for ships, aviation, and automobiles. In the field of civil and transportation engineering, phononic crystal theory has achieved some preliminary results in foundation vibration isolation, foundation pile vibration isolation for traffic environment vibration, and vibration analysis of simple periodic support bridges, mainly focusing on vibration in the low-frequency range. The phononic crystal structure can be regarded as a new material / structure composed of a periodic arrangement of specially designed artificial structural units. By adjusting the geometric / material parameters of the artificial periodic structure, the position and width of the band gap and its ability to suppress wave propagation can be artificially controlled.

[0003] Acoustic black hole is a new concept based on the concept of black hole in astrophysics. In theory, the propagation time of sound waves in the acoustic black hole structure tends to infinity, and the energy of the incident wave will be gathered at the end of the acoustic black hole structure, so that no reflected wave will be generated in the acoustic black hole structure. Mironov and Krylov proposed that changing the thickness of the beam according to a power function can realize a one-dimensional acoustic black hole structure, thereby suppressing the propagation of structural vibration waves. Krylov, Mironov and others subsequently extended the acoustic black hole theory to applications that change simultaneously in two directions, namely, a two-dimensional acoustic black hole structure.

[0004] Most of the current research on periodic pile rows is based on the Bragg scattering mechanism, and the wavelength corresponding to the center frequency of the first band gap is twice the lattice constant. Therefore, if you want to block low-frequency vibrations with a larger wavelength, you need a larger lattice constant, which means that it occupies a larger area and is not conducive to vibration isolation and shock reduction in a limited space. Summary of the invention

[0005] The purpose of the present invention is to provide a new type of phonon transistor pile to address the above-mentioned deficiencies in the prior art, so as to solve the problem that the vertical low-frequency vibration transmitted from the existing soil to the upper structure is difficult to be effectively suppressed.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A novel phonon transistor pile, comprising a pile tip, a pile body and a plurality of ABH-LR combined vibration reduction units;

[0008] The pile tip is located at the bottom end of the pile body; a plurality of ABH-LR combined vibration reduction units are periodically distributed in the pile body from bottom to top along the height of the pile body, and are connected to the pile body through elastic materials.

[0009] Furthermore, the ABH-LR combined vibration reduction unit includes two LR phononic crystal units, two sets of constrained damping layers, and a two-dimensional acoustic black hole plate;

[0010] The two sets of constrained damping layers are respectively arranged on the upper surface and the lower surface at the center of the two-dimensional acoustic black hole plate; the two LR phononic crystal unit cells are respectively connected to the constrained damping layers located on the upper surface and the lower surface of the two-dimensional acoustic black hole plate through elastic materials.

[0011] Furthermore, the LR phononic crystal unit cell includes a LR phononic crystal unit cell shell, a LR phononic crystal unit cell elastic material and a LR phononic crystal unit cell oscillator; the LR phononic crystal unit cell oscillator is arranged in the LR phononic crystal unit cell shell and connected to the LR phononic crystal unit cell shell through the LR phononic crystal unit cell elastic material.

[0012] Furthermore, the constrained damping layer includes a constrained layer and a damping layer; the constrained layer is located at the periphery of the damping layer.

[0013] Furthermore, the two-dimensional acoustic black hole plate is a structure having a shape obtained after two one-dimensional acoustic black holes rotate around a terminal.

[0014] Furthermore, the material of the shell of the LR phononic crystal unit cell is steel or lead or tin or copper or epoxy resin or organic glass;

[0015] The material of the LR phononic crystal unit cell oscillator is steel, lead, tin or copper;

[0016] The material of the LR phononic crystal unit cell elastic material is foamed concrete or rubber or foam or plastic.

[0017] Furthermore, the material of the constraining layer is steel or lead or tin or copper or epoxy resin or organic glass;

[0018] The material of the damping layer is foamed concrete, rubber, foam or plastic.

[0019] Furthermore, the LR phononic crystal unit cell is a circular column or a rectangular column;

[0020] The LR phononic crystal unit cell oscillator is a star-shaped column, a circular column or a rectangular column.

[0021] Furthermore, the elastic material is foamed concrete or rubber or foam or plastic.

[0022] Furthermore, the pile tip is made of steel or alloy steel or other special alloys;

[0023] The material of the pile body is reinforced concrete or alloy steel or steel;

[0024] The material of the two-dimensional acoustic black hole plate is foamed concrete or rubber or foam or plastic or steel or lead or tin or copper or epoxy resin or organic glass.

[0025] The novel phonon transistor pile provided by the present invention has the following beneficial effects:

[0026] 1. The present invention adopts an ABH-LR combined vibration reduction unit in a novel phononic transistor pile, concentrates the vibration at the center of the structure through a two-dimensional acoustic black hole plate, and then sets a constrained damping layer and an LR phononic crystal unit cell in the center of the two-dimensional acoustic black hole plate. The energy dissipation effect of the constrained damping layer and the local resonance effect generated by the LR phononic crystal are used to dissipate energy, so that the pipe pile has an elastic wave band gap characteristic, can effectively filter low-frequency vertical vibrations, and suppress the influence of vertical vibrations on buildings.

[0027] 2. The present invention can suppress the influence of low-frequency vibration in the soil on the building, and can also reduce the influence of seismic waves on the building.

[0028] 3. The present invention can be made of common and cheap building materials such as concrete, steel, rubber, etc., and has good economic efficiency.

[0029] 4. The present invention achieves the suppression of low-frequency vibrations at a sub-wavelength scale. Compared with traditional low-frequency vibration reduction measures such as foundation piles, the present invention has higher spatial efficiency and therefore has a wide range of applications in fields such as urban rail transit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the new phonon transistor pile structure of the present invention.

[0031] Figure 2 It is a front view of the ABH-LR combined vibration reduction unit of the present invention.

[0032] Figure 3 It is a schematic diagram of the cross section of a unit cell of the LR phononic crystal of the present invention.

[0033] Figure 4 It is a schematic diagram of the unit cell structure of the LR phononic crystal of the present invention.

[0034] Figure 5 It is a schematic diagram of the structure of the constrained damping layer of the present invention.

[0035] Figure 6 Schematic diagram of geometric parameters of the two-dimensional acoustic black hole plate of the present invention.

[0036] Figure 7 This is a schematic diagram of the structure of the two-dimensional acoustic black hole plate of the present invention.

[0037] Figure 8 It is a schematic cross-sectional view of the two-dimensional acoustic black hole plate of the present invention.

[0038] Fig. 9 This is a cross-sectional view of the two-dimensional acoustic black hole plate of the present invention.

[0039] Fig.10 This is a top view of the two-dimensional acoustic black hole plate of the present invention.

[0040] Fig.11 This is a finite element model of the phononic crystal unit cell structure of the novel phononic transistor pile of the present invention.

[0041] Fig.12 This is a band gap diagram of the novel phonon transistor pile of the present invention.

[0042] Among them, 1. pile tip; 2. pile body; 3. ABH-LR combined vibration reduction unit; 31. LR phononic crystal unit cell; 311. LR phononic crystal unit cell oscillator; 312. LR phononic crystal unit cell elastic material; 313. LR phononic crystal unit cell shell; 32. constrained damping layer; 321. constrained layer; 322. damping layer; 33. two-dimensional acoustic black hole plate. DETAILED DESCRIPTION

[0043] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0044] Example 1

[0045] This embodiment provides a new type of phonon transistor pile. This embodiment can make the pipe pile have elastic wave band gap characteristics, and the band gap is adjustable, which expands the band gap width and can effectively suppress the vibration transmitted from the soil to the building. Figure 1 , which specifically include:

[0046] Pile tip 1, pile body 2 and several ABH-LR combined vibration reduction units 3;

[0047] The pile tip 1 of the present embodiment is located at the bottom end of the pile body 2, and a plurality of ABH-LR combined vibration reduction units 3 are periodically distributed in the pile body 2 from bottom to top along the height of the pile body.

[0048] Several ABH-LR combined vibration reduction units 3 are connected to the pile body 2 through elastic material. This embodiment does not limit the shape of the elastic material, which can be of any shape and is arranged between the ABH-LR combined vibration reduction units 3 and the pile body 2.

[0049] The novel phonon transistor pile of this embodiment is a reinforced concrete pipe pile or a prestressed pipe pile.

[0050] The above structures will be described in detail below in this embodiment;

[0051] Pile tip 1;

[0052] The pile tip 1 is made of steel or alloy steel or other special alloys.

[0053] Pile body 2;

[0054] The pile body 2 is made of reinforced concrete or alloy steel or steel.

[0055] ABH-LR combined vibration reduction unit 3;

[0056] refer to Figure 2 , the ABH-LR combined vibration reduction unit 3 includes two LR phononic crystal units 31, two sets of constrained damping layers 32, and a two-dimensional acoustic black hole plate 33;

[0057] Specifically, two sets of constrained damping layers 32 are respectively arranged on the upper surface and lower surface at the center of the two-dimensional acoustic black hole plate 33; two LR phononic crystal unit cells 31 are respectively connected to the constrained damping layers 32 located on the upper surface and lower surface of the two-dimensional acoustic black hole plate 33 through elastic materials.

[0058] As a preferred embodiment of this embodiment, refer to Figure 3 and Figure 4 The LR phononic crystal unit cell 31 includes an LR phononic crystal unit cell shell 313, an LR phononic crystal unit cell elastic material 312 and an LR phononic crystal unit cell oscillator 311. The LR phononic crystal unit cell oscillator 311 is arranged in the LR phononic crystal unit cell shell 313 and is connected to the LR phononic crystal unit cell shell 313 through the LR phononic crystal unit cell elastic material 312.

[0059] Among them, the LR phononic crystal unit cell 31 of this embodiment is a circular column or a rectangular column; the LR phononic crystal unit cell oscillator 311 is a star-shaped column or a circular column or a rectangular column.

[0060] The material of the LR phononic crystal unit cell shell 313 of this embodiment is steel, lead, tin, copper, epoxy resin or plexiglass; the material of the LR phononic crystal unit cell oscillator is steel, lead, tin or copper; the material of the LR phononic crystal unit cell elastic material 312 is foamed concrete, rubber, foam or plastic.

[0061] As a preferred embodiment of this embodiment, refer to Figure 5 The constrained damping layer 32 includes a constrained layer 321 and a damping layer 322 , and the constrained layer 321 is located at the periphery of the damping layer 322 .

[0062] The material of the constraint layer 321 of this embodiment is steel, lead, tin, copper, epoxy resin or organic glass; the material of the damping layer 322 is foamed concrete, rubber, foam or plastic.

[0063] refer to Figure 6 to Figure 10 The two-dimensional acoustic black hole plate 33 of this embodiment is a shape structure obtained after two one-dimensional acoustic black holes rotate around the terminal for one circle. The material of the two-dimensional acoustic black hole plate 33 is foamed concrete or rubber or foam or plastic or steel or lead or tin or copper or epoxy resin or organic glass.

[0064] The working principle of a novel phonon transistor pile in this embodiment is:

[0065] The vibration transmitted from the soil to the pipe pile is collected at the center of the two-dimensional acoustic black hole plate 33 through the two-dimensional acoustic black hole plate 33 in the ABH-LR combined vibration reduction unit, and then the restraining effect of the restraining layer 321 in the restrained damping layer 32 on the damping layer 322 causes lateral shear deformation inside the damping layer 322 to initially dissipate the vibration, and finally the vibration is further dissipated through the local resonance effect generated by the LR phononic crystal unit cell arranged above / below the restrained damping layer 32. In addition, the presence of the restrained damping layer 32 reduces the stiffness of the ABH-LR combined vibration reduction unit 3, widens the low-frequency band gap, and improves the vibration reduction efficiency.

[0066] The feasibility of the new phononic transistor pile in vibration reduction applications will be verified below;

[0067] refer to Fig.11 In this embodiment, a finite element model of the phononic crystal unit cell structure of a new phononic transistor pile is established by using finite element software. The finite element software can be used to calculate Figure 4 The mass matrix M and stiffness matrix K of the typical unit structure under free vibration state are shown, combined with the structural dynamics equation |M-ω under free vibration state 2 M|=0, where ω represents the frequency of vibration of the novel phonon transistor pile. Substituting the mass matrix M and stiffness matrix K obtained by finite element software into the equation, we can get Figure 4 The bandgap diagram of the new phononic transistor pile is shown in Fig.12 shown.

[0068] Depend on Fig.12 It can be seen that the new phonon transistor pile structure involved in this embodiment successfully opened the band gap, i.e. 9.58–20.56 Hz, which indicates that elastic waves within this frequency range cannot propagate within the structure, further proving the feasibility of the new phonon transistor pile designed in the present invention in vibration reduction applications.

[0069] Example 2

[0070] This embodiment provides a specific preferred solution based on the structure in Embodiment 1, which specifically includes the following contents:

[0071] The pile tip 1 is made of steel;

[0072] The pile body 2 is made of reinforced concrete.

[0073] The elastic material and the LR phononic crystal unit cell elastic material 312 are both made of rubber;

[0074] The materials of the two-dimensional acoustic black hole plate 33, the LR phononic crystal unit cell shell 313, and the LR phononic crystal unit cell oscillator 311 are steel;

[0075] The material of the constraining layer 321 is steel;

[0076] The damping layer 322 is made of rubber;

[0077] The ABH-LR combined vibration reduction unit is arranged inside the pile; the distance between the ABH-LR combined vibration reduction unit in the longitudinal direction is f;

[0078] The two-dimensional acoustic black hole plate 33 is a shape obtained after two one-dimensional acoustic black holes rotate around the terminal for one circle.

[0079] Specifically, refer to Figure 6 The acoustic black hole cross-section function of the one-dimensional acoustic black hole constituting the two-dimensional acoustic black hole plate 33 has a starting thickness of h1, a cutoff thickness of h2, and a acoustic black hole cross-section function of y=k(R–x) p +h2, where k is the coefficient of the acoustic black hole cross-section function, p is the power index of the acoustic black hole cross-section function, and R is the range of the acoustic black hole; reference Figure 2 to Figure 5 , the height of the LR phononic crystal unit cell 31 is a; the maximum diameter of the LR phononic crystal unit cell shell 313 is D3, and the thickness is (D3–D2) / 2; the minimum thickness of the LR phononic crystal unit cell elastic material 312 is (D2-D1) / 2; the maximum diameter of the LR phononic crystal unit cell oscillator 311 is D 11 , the minimum diameter is D12 The angle formed by connecting the two bottom vertices of the sawtooth structure with the center point of the oscillator is θ; the diameters of the damping layer 322 and the constraint layer 321 are both D4; the thickness of the constraint layer 321 is b; and the thickness of the damping layer 322 is c.

[0080] In this embodiment, h1=20 cm, h2=2.5 cm, R=27 cm, k=3.226×10 -5 , p = 5, y = k(27–x) 5 +2.5, a=20cm, D 11 =25cm, D 12 =20cm, θ=30°, D2=28cm, D3=30cm; D4=32cm; b=0.5cm; c=1.5cm; The band gap frequency of this new type of phonon transistor pile can be designed to be around 15Hz.

[0081] Although the specific implementation of the invention is described in detail in conjunction with the drawings, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A novel phonon transistor pile, characterized in that: It comprises a pile tip (1), a pile body (2) and a plurality of ABH-LR combined vibration reduction units (3); The pile tip (1) is located at the bottom end of the pile body (2); a plurality of ABH-LR combined vibration reduction units (3) are periodically distributed in the pile body (2) from bottom to top along the height of the pile body, and are connected to the pile body (2) via elastic material.

2. The novel phonon transistor pile according to claim 1, characterized in that: The ABH-LR combined vibration reduction unit (3) comprises two LR phononic crystal units (31), two sets of constrained damping layers (32), and a two-dimensional acoustic black hole plate (33); The two sets of constrained damping layers (32) are respectively arranged on the upper surface and the lower surface at the center of the two-dimensional acoustic black hole plate (33); the two LR phononic crystal unit cells (31) are respectively connected to the constrained damping layers (32) located on the upper surface and the lower surface of the two-dimensional acoustic black hole plate (33) through elastic materials.

3. The novel phonon transistor pile according to claim 2, characterized in that: The LR phononic crystal unit cell (31) comprises an LR phononic crystal unit cell shell (313), an LR phononic crystal unit cell elastic material (312) and an LR phononic crystal unit cell oscillator (311); the LR phononic crystal unit cell oscillator (311) is arranged in the LR phononic crystal unit cell shell (313) and is connected to the LR phononic crystal unit cell shell (313) via the LR phononic crystal unit cell elastic material (312).

4. The novel phonon transistor pile according to claim 2, characterized in that: The constrained damping layer (32) comprises a constrained layer (321) and a damping layer (322); the constrained layer (321) is located at the periphery of the damping layer (322).

5. The novel phonon transistor pile according to claim 2, characterized in that: The two-dimensional acoustic black hole plate (33) is a structure having a shape obtained after two one-dimensional acoustic black holes rotate around a terminal.

6. The novel phonon transistor pile according to claim 3 is characterized in that: The material of the LR phononic crystal unit cell shell (313) is steel, lead, tin, copper, epoxy resin or organic glass; The material of the LR phononic crystal unit cell oscillator (311) is steel, lead, tin or copper; The LR phononic crystal unit cell elastic material (312) is made of foamed concrete, rubber, foam or plastic.

7. The novel phonon transistor pile according to claim 4, characterized in that: The material of the constraining layer (321) is steel, lead, tin, copper, epoxy resin or organic glass; The material of the damping layer (322) is foamed concrete, rubber, foam or plastic.

8. The novel phonon transistor pile according to claim 3 is characterized in that: The LR phononic crystal unit cell (31) is in the shape of a circular column or a rectangular column; The LR phononic crystal unit cell oscillator (311) is a star-shaped column, a circular column or a rectangular column.

9. The novel phonon transistor pile according to any one of claims 1 to 8, characterized in that: The elastic material is foamed concrete or rubber or foam or plastic.

10. The novel phonon transistor pile according to any one of claims 1 to 8, characterized in that: The pile tip (1) is made of steel, alloy steel or other special alloys; The material of the pile body (2) is reinforced concrete or alloy steel or steel; The material of the two-dimensional acoustic black hole plate (33) is foamed concrete or rubber or foam or plastic or steel or lead or tin or copper or epoxy resin or organic glass.

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