CN112623109A - Vibration-damping sandwich beam and vibration-damping deck frame - Google Patents

Vibration-damping sandwich beam and vibration-damping deck frame Download PDF

Info

Publication number
CN112623109A
CN112623109A CN202011467007.6A CN202011467007A CN112623109A CN 112623109 A CN112623109 A CN 112623109A CN 202011467007 A CN202011467007 A CN 202011467007A CN 112623109 A CN112623109 A CN 112623109A
Authority
CN
China
Prior art keywords
vibration
damping
layer
load
sandwich
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202011467007.6A
Other languages
Chinese (zh)
Other versions
CN112623109B (en
Inventor
方辉
刘泽
段利亚
刘勇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ocean University of China
Original Assignee
Ocean University of China
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ocean University of China filed Critical Ocean University of China
Priority to CN202011467007.6A priority Critical patent/CN112623109B/en
Publication of CN112623109A publication Critical patent/CN112623109A/en
Application granted granted Critical
Publication of CN112623109B publication Critical patent/CN112623109B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B17/00—Vessels parts, details, or accessories, not otherwise provided for
    • B63B17/0081—Vibration isolation or damping elements or arrangements, e.g. elastic support of deck-houses
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
    • F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
    • F16F15/04—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using elastic means

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Vibration Prevention Devices (AREA)

Abstract

The invention relates to a vibration-damping sandwich beam and a vibration-damping ship plate frame, wherein the vibration-damping sandwich beam comprises a body, and an upper beam, an elastic layer and a lower beam are sequentially arranged on the body from top to bottom; applying an axial load in the length direction of the body, wherein the axial load is smaller than the critical buckling load of the upper-layer beam and larger than the critical buckling load of the lower-layer beam; the lower beam is projected and deformed in the direction of the upper beam under the action of the axial load. The vibration-damping sandwich beam can increase the vibration-damping effect of the structure under the condition that the load frequency, the load amplitude and the proportion of the viscoelastic material are all kept unchanged.

Description

Vibration-damping sandwich beam and vibration-damping deck frame
Technical Field
The invention relates to the technical field of ship plate vibration reduction structures, in particular to a vibration reduction sandwich beam and a vibration reduction ship plate frame.
Background
The ocean and ship engineering structure can bear dynamic external loads such as waves and the like, and effective implementation of vibration reduction becomes a great demand for ensuring the safety of the ocean engineering structure.
In a traditional vibration damping method, viscoelastic materials (such as rubber) and the like are introduced into a protected structure (such as a ship hull plate frame) to improve structural damping so as to realize vibration damping, but the vibration damping effect is limited by load frequency, load amplitude and the proportion of the viscoelastic materials. Therefore, it is necessary to design a better vibration damping structure to increase the vibration damping effect of the structure under the condition that the load frequency, the load amplitude and the proportion of the viscoelastic material are all kept unchanged.
Disclosure of Invention
Aiming at the defects in the prior art, one of the technical problems to be solved by the invention is to provide a vibration-damping sandwich beam which can increase the vibration-damping effect of the structure under the condition that the load frequency, the load amplitude and the proportion of viscoelastic materials are kept unchanged.
The second technical problem to be solved by the invention is to provide a vibration-damping ship plate frame, which can improve the vibration-damping effect of the ship plate frame.
In order to solve one of the technical problems, the invention provides a vibration-damping sandwich beam which comprises a body, wherein the body is provided with an upper beam, an elastic layer and a lower beam from top to bottom in sequence; applying an axial load in the length direction of the body, wherein the axial load is smaller than the critical buckling load of the upper-layer beam and larger than the critical buckling load of the lower-layer beam; the lower beam is projected and deformed in the direction of the upper beam under the action of the axial load.
The damping sandwich beam adopts the sandwich design, the elastic layer is arranged between the upper layer beam and the lower layer beam, the axial load is applied in the length direction of the body, the axial load generates the prestress in the damping sandwich beam, because the axial load is smaller than the critical buckling load of the upper layer beam and larger than the critical buckling load of the lower layer beam, the upper layer beam still keeps a straight line shape after the prestress is applied, and the lower layer beam bends and deforms under the action of the prestress, and the deformation direction is convex towards the upper layer beam. According to vibration mechanics, damping energy consumption is in direct proportion to the square of the vibration frequency of the structure; when the lower layer beam bears the cyclic load within a certain range, the lower layer beam and the upper layer beam both enter a chaotic state, and the high-frequency component in a chaotic wide spectrum increases the structural dissipation; after the cyclic load borne by the lower-layer beam exceeds a certain threshold value, bistable motion is generated under the constraint of the upper-layer beam, namely, the lower-layer beam continuously jumps between two stable states across an unsteady potential barrier, and the beam generates up-conversion vibration when crossing the potential barrier, so that the structural energy consumption is greatly enhanced and the vibration reduction effect is improved by the bistable motion of the lower-layer beam.
Preferably, the elastic layer is made of a viscoelastic material.
Preferably, the upper beam, the elastic layer and the lower beam are sequentially glued.
In order to solve the second technical problem, the invention provides a vibration-damping ship plate frame which comprises a plate body, wherein a plurality of vibration-damping sandwich beams are arranged at the bottom of the plate body, and the plurality of vibration-damping sandwich beams are arranged in parallel at intervals. According to the invention, the damping sandwich beam is applied to the ship plate frame, so that the damping effect of the ship plate frame can be increased, and the structural safety of a ship is protected.
Preferably, the vibration-damping sandwich beam further comprises an end plate arranged at the end part of the body, one end of the body in the length direction is fixedly connected with the plate body, and the other end of the body is fixedly connected with the plate body through the end plate. When the prestress forming device is installed, one end of the body in the length direction is fixedly connected with the plate body, then the end plate is installed, when the prestress forming device is installed, axial load is applied to the body through the end plate, and after the applied axial load reaches a target value, the end plate is fixedly connected with the body and the plate body, so that prestress is formed inside the body.
Preferably, the top of the upper beam abuts the bottom of the panel.
Preferably, the upper beam, the elastic layer and the lower beam are sequentially arranged along the direction far away from the plate body.
Drawings
In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
FIG. 1 is a schematic structural view of a vibration damping sandwich beam according to a first embodiment of the present invention;
fig. 2 is one of amplitude-frequency response curves of the lower beam and the lower beam of the double-layer linear beam under external simple harmonic excitation according to the first embodiment of the present invention;
fig. 3 is one of amplitude-frequency response curves of the upper beam and the upper beam of the double-layer linear beam under external simple harmonic excitation according to the first embodiment of the present invention;
fig. 4 is a second amplitude-frequency response curve of the lower beam of the first embodiment of the present invention and the lower beam of the double-layer linear beam under external simple harmonic excitation;
fig. 5 is a second amplitude-frequency response curve of the upper beam of the first embodiment of the present invention and the upper beam of the double-layer linear beam under the external simple harmonic excitation;
fig. 6 is a schematic structural view of a vibration damping ship plate frame according to a second embodiment of the present invention;
fig. 7 is a schematic structural view of a conventional ship plate frame.
Description of the drawings:
1-an upper beam; 2-an elastic layer; 3-a lower beam; 4-a plate body; 5-end plate.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
Example one
As shown in fig. 1, the present embodiment provides a vibration damping sandwich beam, which includes a body, an upper beam 1, an elastic layer 2 and a lower beam 3, which are sequentially bonded to the body from top to bottom, wherein the elastic layer 2 is made of a viscoelastic material, such as rubber; an axial load P is applied in the length direction of the body, the axial load P is smaller than the critical buckling load of the upper-layer beam and larger than the critical buckling load of the lower-layer beam, and the lower-layer beam 3 is convexly deformed in the direction of the upper-layer beam 1 under the action of the axial load P.
The vibration reduction effect of the vibration reduction sandwich beam provided in the first embodiment is analyzed through theoretical analysis.
When the axial load P is smaller than the upper beam and larger than the critical buckling load of the lower beam, the large transverse displacement, moderate rotation and small strain caused by the beams are consideredGeometric nonlinearity, namely obtaining a transverse motion equation of the sandwich beam by applying a von-Karman nonlinear strain displacement relation model according to a Hamilton energy principle:
Figure BDA0002834662690000045
Figure BDA0002834662690000041
wherein, wb(x, t) is the transverse displacement of the lower beam, ρbIs the mass density of the lower beam, AbIs the cross-sectional area of the lower beam, d1Damping coefficient of the lower beam, EbIs the modulus of elasticity of the lower beam, IbIs the section moment of inertia of the lower beam, P is the axial load, l is the length of the beam, d2Is the damping coefficient of the elastic layer, KlIs the stiffness coefficient of the elastic layer, we(x, t) is the lateral displacement of the upper beam, ρeMass density of the upper beam, AeIs the cross-sectional area of the upper beam, EeIs the modulus of elasticity of the upper beam, IeIs the section moment of inertia, q, of the upper beamwIs the lateral excitation to which the upper beam is subjected (see fig. 1).
Using the Galerkin method to pair wb(x, t) and we(x, t) discretizing to obtain:
Figure BDA0002834662690000046
Figure BDA0002834662690000042
wherein the content of the first and second substances,
Figure BDA0002834662690000043
is a function of the time of motion of the ith order mode of the lower and upper beams, respectivelyi(x) The mode function of the clamped beam at two ends is as follows:
Figure BDA0002834662690000044
wherein, betaiIs the characteristic equation cos (. beta.)il)cosh(βil) 1 root.
Mixing the above wb(x, t) and weThe discrete expressions of (x, t) are substituted into equations (1), (2), and the resulting equations are multiplied by the mode function and integrated with x in the length domain of the beam. Considering that the external excitation frequency is mainly concentrated near the first-order modal frequency of the beam, the continuous composite structure is simplified into a two-degree-of-freedom spring mass model, and the transverse vibration equation is as follows:
Figure BDA0002834662690000051
Figure BDA0002834662690000052
in the formulae (6) and (7),
Figure BDA0002834662690000053
Figure BDA0002834662690000054
Figure BDA0002834662690000055
wherein, F is the external simple harmonic excitation amplitude, and omega is the external excitation frequency.
When the sandwich beam with certain bearing capacity is excited by simple harmonics, the motion characteristics of the system in different frequency bands are changed along with the increase of the excitation amplitude, and an amplitude-frequency response curve of the system changing along with the excitation amplitude is given, as shown in corresponding curves of an upper layer beam and a lower layer beam of the sandwich beam in fig. 2 to 5, for convenient comparison and analysis, the same initial curve is also given in fig. 2 to 5Amplitude-frequency response curve of a rigid linear sandwich beam, i.e. a sandwich beam without axial load P acting thereon, exerting the same transverse external load q on the linear sandwich beamwThe amplitude-frequency response curves of the two-layer linear beam are shown in corresponding curves of the lower layer beam of the two-layer linear beam and the upper layer beam of the two-layer linear beam in fig. 2, 3, 4 and 5.
As can be seen from fig. 2 and 3, near the resonance region, the sandwich beam is in a quasi-periodic or chaotic motion state, and vibration energy is dispersed over a wide frequency band, so that while vibration suppression is realized, response output of the wide frequency band is also realized.
Comparing fig. 4 and 5, it can be seen that the system does periodic motion near the resonance region, but the response amplitude of the system is reduced. In a low frequency or high frequency band, the system can generate multiple period bifurcation, quasi-periodic motion or chaotic motion, thereby realizing broadband response output characteristics except for a frequency band near a resonance region, and keeping the amplitude of vibration and the periodic motion of the linear system at a lower level.
Example two
As shown in fig. 6, the embodiment discloses a vibration damping ship plate frame, which includes a plate body 4, wherein a plurality of vibration damping sandwich beams disclosed in the first embodiment are arranged at the bottom of the plate body 4, and the plurality of vibration damping sandwich beams are arranged in parallel at intervals. Wherein, the top of upper beam 1 and the bottom butt of plate body 4, and upper beam 1, elastic layer 2 and lower floor's roof beam 3 set gradually along the direction of keeping away from plate body 4.
Specifically, the damping sandwich beam further comprises an end plate 5 arranged at the end of the body, one end of the body in the length direction is fixedly connected with the plate body 4, and the other end of the body is fixedly connected with the plate body 4 through the end plate 5. When the prestress-forming plate is installed, one end of the body in the length direction is fixedly connected with the plate body 4, then the end plate 5 is installed, when the prestress-forming plate is installed, axial load is applied to the body through the end plate 5, and after the applied axial load reaches a target value, the end plate 5 is fixedly connected with the body and the plate body, so that prestress is formed inside the body.
Referring to fig. 7, the existing ship plate frame uses L-shaped metal beams to support the plate body (i.e. stiffened plates), the sandwich beam provided by the invention is used for a ship plate frame structure, and the novel sandwich beam is used for replacing the traditional linear beam (such as the L-shaped beam shown in fig. 7), so that the novel damping ship plate frame is obtained as shown in fig. 6, and the damping ship plate frame structure can greatly reduce the structural vibration in the ship operation process.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not cause the essence of the corresponding technical solution to depart from the scope of the technical solution of the embodiments of the present invention, and are intended to be covered by the claims and the specification of the present invention.

Claims (7)

1. The damping sandwich beam comprises a body and is characterized in that:
the body is provided with an upper beam, an elastic layer and a lower beam from top to bottom in sequence;
applying an axial load in the length direction of the body, wherein the axial load is smaller than the critical buckling load of the upper-layer beam and larger than the critical buckling load of the lower-layer beam;
the lower beam is projected and deformed in the direction of the upper beam under the action of the axial load.
2. The vibration damping sandwich beam of claim 1, wherein:
the elastic layer is made of a viscoelastic material.
3. The vibration damping sandwich beam of claim 1, wherein:
the upper beam, the elastic layer and the lower beam are sequentially glued.
4. A vibration damping pallet frame, comprising:
a plate body, wherein a plurality of the vibration-damping sandwich beams according to claim 1 are arranged at the bottom of the plate body, and the plurality of the vibration-damping sandwich beams are arranged in parallel at intervals.
5. A vibration absorbing slate for shipping as set forth in claim 4, wherein:
the damping sandwich beam also comprises an end plate arranged at the end part of the body, one end of the body in the length direction is fixedly connected with the plate body, and the other end of the body is fixedly connected with the plate body through the end plate.
6. A vibration absorbing slate for shipping as set forth in claim 5, wherein:
the top of the upper beam is abutted against the bottom of the plate body.
7. A vibration absorbing slate for shipping as set forth in claim 5, wherein:
the upper beam, the elastic layer and the lower beam are sequentially arranged along the direction away from the plate body.
CN202011467007.6A 2020-12-14 2020-12-14 Vibration-damping sandwich beam and vibration-damping deck frame Active CN112623109B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011467007.6A CN112623109B (en) 2020-12-14 2020-12-14 Vibration-damping sandwich beam and vibration-damping deck frame

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011467007.6A CN112623109B (en) 2020-12-14 2020-12-14 Vibration-damping sandwich beam and vibration-damping deck frame

Publications (2)

Publication Number Publication Date
CN112623109A true CN112623109A (en) 2021-04-09
CN112623109B CN112623109B (en) 2022-03-04

Family

ID=75312983

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011467007.6A Active CN112623109B (en) 2020-12-14 2020-12-14 Vibration-damping sandwich beam and vibration-damping deck frame

Country Status (1)

Country Link
CN (1) CN112623109B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050019590A1 (en) * 2001-09-10 2005-01-27 Percy Josefsson Vibration damping material and vibration damper
CN101678891A (en) * 2007-05-14 2010-03-24 空中客车英国有限公司 Reinforced panel
CN105836164A (en) * 2016-04-27 2016-08-10 北京空间飞行器总体设计部 Interstage adaptive structure of spacecraft
CN108058454A (en) * 2017-12-28 2018-05-22 天津大学 A kind of adaptive damping noise reduction foam layer plate and preparation method thereof
CN209654515U (en) * 2018-11-27 2019-11-19 珠海格力电器股份有限公司 A kind of vibration absorber and the fastener comprising it
CN110566620A (en) * 2019-09-30 2019-12-13 中国海洋大学 Negative-stiffness unit-cell honeycomb vibration damping structure

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050019590A1 (en) * 2001-09-10 2005-01-27 Percy Josefsson Vibration damping material and vibration damper
CN101678891A (en) * 2007-05-14 2010-03-24 空中客车英国有限公司 Reinforced panel
CN105836164A (en) * 2016-04-27 2016-08-10 北京空间飞行器总体设计部 Interstage adaptive structure of spacecraft
CN108058454A (en) * 2017-12-28 2018-05-22 天津大学 A kind of adaptive damping noise reduction foam layer plate and preparation method thereof
CN209654515U (en) * 2018-11-27 2019-11-19 珠海格力电器股份有限公司 A kind of vibration absorber and the fastener comprising it
CN110566620A (en) * 2019-09-30 2019-12-13 中国海洋大学 Negative-stiffness unit-cell honeycomb vibration damping structure

Also Published As

Publication number Publication date
CN112623109B (en) 2022-03-04

Similar Documents

Publication Publication Date Title
CN112582035B (en) Recoverable six-direction buffering energy-absorbing metamaterial and design method thereof
Giaralis et al. Optimum design of the tuned mass-damper-inerter for serviceability limit state performance in wind-excited tall buildings
Abdelmoula et al. Control of base-excited dynamical systems through piezoelectric energy harvesting absorber
Salazar et al. Energy dissipation at PR frames under seismic loading
Poon et al. Dynamic stability of a curved beam under sinusoidal loading
Sheng et al. Synthetical vibration reduction of the nonlinear acoustic metamaterial honeycomb sandwich plate
CN112623109B (en) Vibration-damping sandwich beam and vibration-damping deck frame
Kang et al. Study on vibration suppression of an inclined cable with a nonlinear energy sink under the axial excitation
Gadagi et al. Dynamic response of an axially loaded tendon of a tension leg platform
Smith Finite strip analysis of the dynamic response of beam and slab highway bridges
US9376807B2 (en) Passive structures with high stiffness and high damping properties
CN108978924B (en) Tension-compression loading type mild steel damper with replaceable function
CN103966942A (en) Structure system used for controlling longitudinal response of girder of cable-stayed bridge with three towers and pylon
CN110979557B (en) Free vibration suppression structure based on bistable state-linear coupling and linear plate frame
JP2817579B2 (en) Cordage structure
CN111810568B (en) Steady-state controllable composite pressure lever and transient vibration suppression structure based on same
CN111255841B (en) Three-layer laminating pressure lever and transient vibration suppression structure based on same
Gandhi Influence of nonlinear viscoelastic material characterization on performance of constrained layer damping treatment
JP2002266936A (en) Base isolation device
JP2730475B2 (en) High bending rigid laminated rubber bearing
CN111043213A (en) Stable-state controllable laminated compression bar and transient vibration suppression structure based on same
JP2006316978A (en) Composite viscous elastic damper
CN217461015U (en) Track type mass damper
CN211815545U (en) Variable-curvature three-stage fortification friction pendulum damping and shock insulation support
Baetu et al. Dynamic nonlinear analysis of structural reinforced concrete walls energy dissipators with shear connections

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant