CN105672063A - Fixed-frequency nonlinear rubber vibration isolator for floating slab track and design method - Google Patents

Abstract

The invention provides a fixed-frequency nonlinear rubber vibration isolator for a floating slab track and a design method. It is guaranteed that in an empty vehicle state, a floating slab track bed has the same vibration isolation performance and the unchanged inherent frequency as those in a heavy vehicle state, the track vertical displacement in the heavy vehicle state is effectively restrained, and the system safety is guaranteed. The fixed-frequency nonlinear rubber vibration isolator comprises a base 1, a conic rubber pile, an upper supporting seat, a heightening cushion board and a locking screw, the top face of the base is attached to the inner conic face of the conic rubber pile, and the bottom face of the upper supporting seat is attached to the outer conic face of the conic rubber pile. The conic rubber pile comprises an inner conic steel disc, an outer conic steel disc and at least one layer of conic rubber body located between the inner conic steel disc and the outer conic steel disc and fixedly connected with the inner conic steel disc and the outer conic steel disc. Each conic rubber body is composed of conic rubber ring units arranged along the conic faces of the inner conic steel disc and the outer conic steel disc at intervals. Each conic rubber ring unit is provided with an exhausting channel communicating with the outer side of the vibration isolator.

Description

A kind of the floating plate track non-linear rubber shock absorber of fixed frequency and method of design

Technical field

The present invention relates to railroad track, in particular to a kind of be applicable to the floating plate tracks such as subway, light rail, inter-city passenger rail, high-speed railway determine the non-linear rubber shock absorber of frequency, and the method for design of this fixed non-linear rubber shock absorber frequently.

Background technology

Floating plate track is a kind of effective ways solving the ambient vibration problem that track traffic causes. Floating plate track, by arranging Elastic Isolator under track plate, by the vibration of track plate and base isolation, reaches the object reducing the ambient vibration that track traffic causes. Floating plate track is a mass-spring-damper vibrating isolation system in essence. Current floating plate mainly adopts steel spring vibration isolator and common rubber shock absorber. The stiffness characteristics of these two kinds of vibration isolators is all linear rigidity or close to linear rigidity. But the size of quality can because there is noticeable change in train load-carrying difference in this quality spring vibration isolation system of floating plate track-vehicle. This makes the natural frequency of the floating plate track system based on single-mode system natural frequency method design under different load-carrying operating mode widely different, cause the problems such as empty wagons loaded vehicle state system performance is inconsistent, and empty wagons state anti-vibration performance is poor, loaded vehicle state track vertical deviation is excessive.

Floating plate track rubber shock absorber has all been carried out research and design by lot of domestic and international research institution, defines multiple floating plate track rubber shock absorber patent.

Chinese patent ZL200410035441.1 discloses a kind of railway floating plate railway roadbed, and railway roadbed comprises floating plate and spring vibration-isolator, and floating plate flexibly supports with on spring vibration-isolator. In addition in order to overcome floating ballast bed shortcoming on construction, maintenance in patent ZL200410035441.1, the patents such as a kind of floating ballast bed (ZL200910013963.4), a kind of side floating track bed and application (ZL200910019531.4), new precast panel piecing assembly floating ballast bed (ZL201210452046.8), the lap jointing type floating ballast bed (ZL201420835219.9) that are easy to safeguard are invented again.

Chinese patent ZL200810034584.9 discloses a kind of floating plate vibration isolator for track traffic, and vibration isolator comprises undersetting, rubber damping circle and height-regulating device composition. Vibration isolator can better meet the requirement of railway roadbed height control.

Chinese patent ZL201220294143.4 discloses a kind of board-like rubber damping vibration isolator for floating plate track. This vibration isolator is sulfided into a tabular vibration isolator by rubber and upper and lower two block plates. Hollow out threaded hole in vibration isolator is filled with damping agent to improve vibration isolator damping.

Chinese patent ZL201320385451.2 discloses a kind of rubber shock absorber for orbit traffic floating board, vibration isolator by a circular ring type rubber damper as in end basin, it may be achieved the vibration isolation function of vertical direction.

The rubber shock absorber scheme of above patent, but all can realize basic vibration isolation and shake on vertical. But the train adaptability of different load-carrying operating mode is poor, consistent anti-vibration performance can not be provided, because of be limited to loaded vehicle by time excessive track vertical deviation, therefore cannot improve floating plate anti-vibration performance further. All there is the defect that empty wagons state anti-vibration performance is poor, loaded vehicle state track vertical deviation is excessive in existing spring vibration-isolator.

Summary of the invention

One of technical problem to be solved by this invention is to provide the fixed non-linear rubber shock absorber frequently of a kind of floating plate track, guarantee that floating plate railway roadbed has the anti-vibration performance same with loaded vehicle state and constant natural frequency in empty wagons state, and loaded vehicle state track vertical deviation is effectively suppressed, it is ensured that the security of system.

It is as follows that the present invention solves the problems of the technologies described above the technical scheme taked:

A kind of floating plate track of the present invention non-linear rubber shock absorber of fixed frequency, comprise base, conical rubber pile, upper support seat, height adjusting cushion plate and lock screw, the end face of base and the inner conical surface of conical rubber pile fit, the bottom surface of upper support seat and the outer conical surface of conical rubber pile fit, it is characterized in that: described conical rubber pile comprises coaxial inner conical steel disk, outer inner conical steel disk, and it is positioned at inner conical steel disk, between outer inner conical steel disk and at least one layer of cone rubber body being fixedly connected with it, cone rubber body is by along inner conical steel disk, outer inner conical steel disk conical surface cone rubber ring element separately is formed, each cone rubber ring element has the exhaust-duct led to outside vibration isolator.

Another technical problem to be solved by this invention is to provide the method for design of above-mentioned a kind of floating plate track with fixed non-linear rubber shock absorber frequently, and this method of design comprises the steps:

(1) according to designed rigidity benchmark rigidity k₀, the vertical basis displacement x of basis displacement₀And rigidity function K (x), draw vibration isolator stiffness curve and vibration isolator load curve;

(2) ultimate load is born according to track, vibration isolator load curve is looked into the operation interval getting vibration isolator and maximum functional displacement, determine conical rubber pile thickness and cone angle, choose the preliminary project of rubber heap nonlinear geometry structure formation and elastomeric material;

(3) set up the finite element model of the fixed heap parametrization of non-linear rigidity rubber frequently according to preliminary project, wherein material model adopts non-linear rubber cast, it is contemplated that the contact relation of geometrically nonlinear structure in rubber deformation process;

(4) setting natural frequency error and the natural frequency stability optimization design index as vibration isolator parameter designing, natural frequency error is vibration isolator error between natural frequency average and design load in working range;Natural frequency stability is the fluctuating range of vibration isolator natural frequency in working range;

(5) according to described optimization design index, utilize Finite Element Method to carry out mechanical property calculating described finite element model, obtain the optimization design desired value corresponding to described finite element model;

(6) the optimization design desired value obtained according to described optimization design index and calculating, carries out multiple-objection optimization iterative computation, obtains optimal solution set, and determine vibration isolator optimal design parameters and optimizing index value from optimal solution set;

(7) if vibration isolator optimal design parameters and optimizing index value meet design requirement, terminate design, if can not meet design requirement, then adjust vibration isolator topological framework, repeating step (3)～(6).

The invention has the beneficial effects as follows, provide method of design and the implementation thereof of a kind of fixed rubber shock absorber non-linear rigidity curve frequently, overcome the defect that empty wagons state anti-vibration performance is poor, loaded vehicle state track vertical deviation is excessive that common spring vibration-isolator linear rigidity causes. Can guarantee that floating plate rail system all has constant natural frequency when any car weight, stable anti-vibration performance. And loaded vehicle state track vertical deviation is effectively suppressed, it is ensured that the security of system. At resonant frequencyDoubly above frequency separation damping capacity reaches 20～30dB, it is possible to meet Special zone anti-vibration performance requirement; Owing to rubber has bigger viscous damping, therefore near resonant frequency, but it still has performance of better shaking, and is better than ordinary steel spring floating plate track. Described rubber shock absorber is replaceable, easy-maintaining, both can be applicable to prefabricated floating plate track, it is possible to for cast-type floating plate track.

Accompanying drawing explanation

This specification sheets comprises following five width accompanying drawings:

Fig. 1 is the structural representation of a kind of floating plate track of the present invention with fixed non-linear rubber shock absorber frequently;

Fig. 2 is the structural representation of a kind of floating plate track of the present invention with conical rubber pile in fixed non-linear rubber shock absorber frequently;

Fig. 3 is the structural representation of a kind of floating plate track of the present invention with conical rubber pile in fixed non-linear rubber shock absorber frequently;

Involved in the method for design that Fig. 4 is a kind of floating plate track of the present invention with fixed non-linear rubber shock absorber frequently determine frequency non-linear rigidity graphic representation;

Involved in the method for design that Fig. 5 is a kind of floating plate track of the present invention with fixed non-linear rubber shock absorber frequently determine the non-linear load curve figure of frequency;

Mark and implication thereof in figure: base 1, conical rubber pile 2, upper support seat 3, height adjusting cushion plate 4, lock screw 5, inner conical steel disk 31, outer inner conical steel disk 32, middle taper steel disk 33, cone rubber ring element 34, conical rubber pile upper inner diameter p, conical rubber pile cone angle, cone rubber body thickness in monolayer h, the width S in cone rubber ring gap₁、S₂、S₃。

Embodiment

Below in conjunction with accompanying drawing and specific embodiments, the present invention is further described.

With reference to Fig. 1, Fig. 2 and Fig. 3, a kind of floating plate track of the present invention non-linear rubber shock absorber of fixed frequency, comprise base 1, conical rubber pile 2, upper support seat 3, height adjusting cushion plate 4 and lock screw 5, the end face of base 1 and the inner conical surface of conical rubber pile 2 fit, and the bottom surface of upper support seat 3 and the outer conical surface of conical rubber pile 2 fit. Described conical rubber pile 2 comprises coaxial inner conical steel disk 31, outer inner conical steel disk 32, and between inner conical steel disk 31, outer inner conical steel disk 32 and at least one layer of cone rubber body being fixedly connected with it, cone rubber body is formed by along inner conical steel disk 31, outer inner conical steel disk 32 conical surface cone rubber ring element 34 separately, and each cone rubber ring element 34 has the exhaust-duct 35 led to outside vibration isolator.The line style of the non-linear rigidity curve of rubber structure is formed by the gap arranged in cone rubber body, rubber heap integral rigidity is controlled by cone rubber body thickness and rubber compounding, by the ratio of the cone angle of the conical rubber pile control horizontal rigidity of rubber heap and vertical stiffness, guarantee that floating plate railway roadbed has the anti-vibration performance same with loaded vehicle state and constant natural frequency in empty wagons state, and loaded vehicle state track vertical deviation is effectively suppressed, it is ensured that the security of system.

With reference to Fig. 3, described inner conical steel disk 31, the cone rubber body between outer inner conical steel disk 32 can be one layer or multilayer. When cone rubber body is multilayer, middle taper steel disk 33 is set between layer.

With reference to Fig. 3, when vibration isolator is pressed, each cone rubber ring element 34 can expand to both sides and progressively eat up gap each other, and adjacent two cone rubber ring elements 34 come in contact limit value rubber swelling, so that vibration isolator rigidity increases. Change according to certain functional form by arranging gap width and being partitioned into of gap, so that it may to control the change curve of rigidity.

A kind of floating plate track of the present invention method of design of fixed non-linear rubber shock absorber frequently, comprises the steps:

(1) according to designed rigidity benchmark rigidity k₀, the vertical basis displacement x of basis displacement₀And rigidity function K (x), draw vibration isolator stiffness curve and vibration isolator load curve;

(2) ultimate load is born according to track, vibration isolator load curve is looked into the operation interval getting vibration isolator and maximum functional displacement, determine conical rubber pile thickness and cone angle, choose the preliminary project of rubber heap nonlinear geometry structure formation and elastomeric material;

(3) set up the finite element model of the fixed heap parametrization of non-linear rigidity rubber frequently according to preliminary project, wherein material model adopts non-linear rubber cast, it is contemplated that the contact relation of geometrically nonlinear structure in rubber deformation process;

(4) set natural frequency error and natural frequency stability as the optimization design target of vibration isolator parameter designing, comprising: natural frequency error, error between natural frequency average and design load in working range; Natural frequency stability, the fluctuating range of natural frequency in working range;

(5) according to described optimization design target, utilize Finite Element Method to carry out mechanical property calculating described finite element model, obtain the optimization design target value corresponding to described finite element model;

(6) the optimization design target value obtained according to described optimization design target and calculating, carries out multiple-objection optimization iterative computation, obtains optimal solution set, and determine vibration isolator optimal design parameters and optimizing index value from optimal solution set;

(7) if vibration isolator optimal design parameters and optimizing index value meet design requirement, terminate design, if can not meet design requirement, then adjust vibration isolator topological framework, repeating step (3)～(6).

In described step (1), vibration isolator stiffness curve and vibration isolator load curve are determined by following formula:

$K\left(x\right)=\left\{\begin{array}{cc}\frac{{\mathrm{dk}}_0}{2}& x\≤x_0\\ \frac{{\mathrm{d\αe}}^{\frac{{\mathrm{\ω}}^2}{4{\mathrm{g\π}}^2}x}}{2}& x>x_0\end{array}\right.$

In formula, k₀For vibration isolator benchmark rigidity, d is vibration isolator arrangement pitch, and ω is system frequency, x₀For the static vertical basis displacement of floating plate.

Benchmark rigidity and basis displacement are determined: according to floating plate track system isolation performance and trajectory stability requirement, it is determined that the static vertical basis displacement x under the natural frequency ω of train floating plate track system and track plate deadweight effect₀. Floating plate track is utilized often to prolong meter Chong Liang m_s, and vibration isolator arrangement pitch d, it is determined that vibration isolator benchmark rigidity k₀:

k₀=4 π²ω²m_s

Fixed non-linear rigidity curve frequently is determined: utilize the firm k of rubber shock absorber benchmark obtained₀With vertical basis displacement x₀, determine the adjusted value α of stiffness curve k (x) according to the following formula,

$\mathrm{\α}=\frac{k_0}{e^{\frac{{\mathrm{\ω}}^2}{4{\mathrm{g\π}}^2}{x}_0}}$

It is as follows that nonlinear curve proposed by the invention realizes fixed principle frequently:

Calculating formula according to quality spring system natural frequency:

$\mathrm{\ω}=\frac{1}{2\mathrm{\π}}\sqrt{\frac{k}{m}}$

If it will be seen that the ratio being guaranteed the rigidity k and quality m of the constant spring system that just needs to ensure the quality of products of system vibrational frequency is constant.Therefore spring rigidity should be the nonlinear curve along with vibration isolator change in displacement, is designated as k (x),

K (x)=4 π²ω²m

And the spring distortion caused by the gravity of quality m can be obtained by following formula,

$m=\frac{1}{g}\∫k\left(x\right)dx$

Comprehensive above two formulas obtain

$k\left(x\right)=\frac{4{\mathrm{\π}}^2{\mathrm{\ω}}^2}{g}\∫k\left(x\right)dx$

Above non trivial solution is,

$k\left(x\right)={\mathrm{\αe}}^{\frac{4{\mathrm{\π}}^2{\mathrm{\ω}}^2}{g}x}$

But this solution needs x field of definition to be met for (-∞, ∞) Shi Caineng, but in reality, the gravity of quality m to the effect of spring facing one direction always, namely always has x >=0, and for guaranteeing that non trivial solution is effective, appeal formula is carried out correction can obtain

$k\left(x\right)=\left\{\begin{array}{cc}{k}_0& x\≤x_0\\ {\mathrm{\αe}}^{\frac{4{\mathrm{\π}}^2{\mathrm{\ω}}^2}{g}x}& x>x_0\end{array}\right.$

Stiffness curve given by upper formula can ensure that it is constant that frequency remains ω as x >=x0. Considering that floating plate is discrete support, vibration isolator spacing is stiffness curve K (x) that d then can obtain vibration isolator. Embodiment:

Requiring to determine that floating plate track system frequency ω is 9Hz according to vibration isolation, often prolonging meter Zi Chong according to Structural Design Requirement track plate is 3000kg, the initial vertical deviation x of vibration isolator₀For 0.3mm. Vibration isolator arrangement pitch d is 1.8m.

First, determine floating plate track reference support rigidity k according to formula (2)₀:

k₀=4 π²ω²M=4 π²×8²× 3000=7.57 × 10⁶N/m

$x_0=\frac{m_s}{k_0}=\frac{3000}{7.56}\×{10}^{-6}=0.3mm$

Then, utilize A to walk the firm k of rubber shock absorber benchmark obtained₀With vertical basis displacement x₀, determine the adjusted value α of stiffness curve k (x) according to the following formula,

$\mathrm{\α}=\frac{k_0}{e^{\frac{4{\mathrm{\π}}^2{\mathrm{\ω}}^2}{g}{x}_0}}=\frac{7.57\×{10}^6}{e^{\frac{4{\mathrm{\π}}^2{8}^2}{9.8}\×0.3\×{10}^6}}=7.00\×{10}^6$

Above-mentioned value being substituted into following formula and can obtain the stiffness curve of vibration isolator such as Fig. 4, load curve is such as Fig. 5.

$K\left(x\right)=\left\{\begin{array}{cc}\frac{{\mathrm{dk}}_0}{2}& x\≤x_0\\ \frac{{\mathrm{d\αe}}^{\frac{{\mathrm{\ω}}^2}{4{\mathrm{g\π}}^2}x}}{2}& x>x_0\end{array}\right.$

Based on gained, non-linear rigidity graphic representation, fixed non-linear load curve figure frequently carry out non-linear rigidity rubber shock absorber elastic element structure design frequently surely frequently surely.

Conical rubber pile 2 is the core component of the non-linear rigidity designed by realization, and Fig. 3 is the structure example determining frequency non-linear rigidity rubber heap. Cone rubber adopts Multi-layer design, and cone rubber 32 is sandwiched between taper steel disk 31. And steel disk and rubber bound are integrated. Space S is set in cone rubber₁、S₂、S₃, cone rubber thickness in monolayer h, minimum diameter d, cone angle. Wherein cone rubber thickness in monolayer h, minimum diameter d, cone angle is cone rubber vertical stiffness and the controling parameters of horizontal stiffness ratio. By arranging space S in adjustment rubber compounding and cone rubber₁、S₂、S₃Quantity and the size in each gap adjust rubber non-linear stiffness curve line style.

Vibration isolator parameter designing process is as follows:

(1) according to vibration isolator vertical stiffness benchmark value k₀, and vertical stiffness and horizontal stiffness ratio require comprehensively tentatively to determine rubber shock absorber cone rubber thickness in monolayer h, minimum diameter d, the initial value { h of cone angle₀, d₀, α₀, and get and determine vibration isolator gap number n is set, and corresponding gap { S₁, S₂, S₃…S_n;

(2) vibration isolator being carried out parametric modeling, establishment vibration isolator modeling program P1, by parameter collection { h to be optimized₀, d₀, α₀, S₁, S₂, S₃…S_nAs optimization variable. Set up the parameter finite element model of vibration isolator cone rubber. This example can change shape and the stiffness characteristics thereof of cone rubber by revising the value of parameters optimization collection;

(3) natural frequency error e and the natural frequency stability r optimization aim as vibration isolator parameter designing is set, 1. natural frequency error, i.e. error between natural frequency ω average and design load in working range; 2. natural frequency stability, the i.e. fluctuating range of natural frequency ω in working range; Establishment design objective computation program P2, program P2 are input as target stiffness curve and vibration isolator stiffness curve.

(4) adopt method of least squares, utilize Matlab software programming weighting multiple-objection optimization program, program first calling program P1 set up vibration isolator model, generation model script.Then read in finite element model script by driven by program finite element software, and load course is set, calculate the displacement-force curve of vibration isolator under given load course, and ask to lead and obtain its stiffness curve. Then calling program P2 obtains this optimization aim calculated, and utilizes method of least squares to design variable { h₀, d₀, α₀, S₁, S₂, S₃…S_nIt is optimized acquisition optimum solution set.

(5) optimization aim natural frequency error e and natural frequency stability r is checked. If the optimum value of gained optimization design target meets design requirement, terminate design, if can not meet design requirement, then adjust vibration isolator number of gaps n, and repeating step (2)-(4).

The above is just by stiffness curve and method of design, mode of operation and the principle of the fixed non-linear rigidity conical rubber pile vibration isolator frequently of graphic extension floating plate track of the present invention, it is not the present invention is confined in shown and described concrete structure and the scope of application, therefore every corresponding modify of being likely utilized and etc. jljl, all belong to the patent scope that the present invention applies for.

Claims (4)

1. the floating plate track non-linear rubber shock absorber of fixed frequency, comprise base (1), conical rubber pile (2), upper support seat (3), height adjusting cushion plate (4) and lock screw (5), the end face of base (1) and the inner conical surface of conical rubber pile (2) fit, the bottom surface of upper support seat (3) and the outer conical surface of conical rubber pile (2) fit, it is characterized in that: described conical rubber pile (2) comprises coaxial inner conical steel disk (31), outer inner conical steel disk (32), and it is positioned at inner conical steel disk (31), between outer inner conical steel disk (32) and at least one layer of cone rubber body being fixedly connected with it, cone rubber body is by along inner conical steel disk (31), outer inner conical steel disk (32) conical surface cone rubber ring element (34) separately is formed, each cone rubber ring element (34) has the exhaust-duct (35) led to outside vibration isolator.

2. a kind of floating plate track, with fixed non-linear rubber shock absorber frequently, is characterized in that: described cone rubber body is multilayer as claimed in claim 1, arranges middle taper steel disk (33) between layer.

3. a kind of floating plate track use determines the method for design of non-linear rubber shock absorber frequently as claimed in claim 1 or 2, comprises the steps:

(1) according to designed rigidity benchmark rigidity k₀, the vertical basis displacement x of basis displacement₀And rigidity function K (x), draw vibration isolator stiffness curve and vibration isolator load curve;

(2) ultimate load is born according to track, vibration isolator load curve is looked into the operation interval getting vibration isolator and maximum functional displacement, determine conical rubber pile thickness and cone angle, choose the preliminary project of rubber heap nonlinear geometry structure formation and elastomeric material;

(3) set up the finite element model of the fixed heap parametrization of non-linear rigidity rubber frequently according to preliminary project, wherein material model adopts non-linear rubber cast, it is contemplated that the contact relation of geometrically nonlinear structure in rubber deformation process;

(4) set natural frequency error and natural frequency stability as the optimization design target of vibration isolator parameter designing, comprising: natural frequency error, error between natural frequency average and design load in working range; Natural frequency stability, the fluctuating range of natural frequency in working range;

(5) according to described optimization design target, utilize Finite Element Method to carry out mechanical property calculating described finite element model, obtain the optimization design target value corresponding to described finite element model;

(6) the optimization design target value obtained according to described optimization design target and calculating, carries out multiple-objection optimization iterative computation, obtains optimal solution set, and determine vibration isolator optimal design parameters and optimizing index value from optimal solution set;

(7) if vibration isolator optimal design parameters and optimizing index value meet design requirement, terminate design, if can not meet design requirement, then adjust vibration isolator topological framework, repeating step (3)～(6).

4. method of design as claimed in claim 3, is characterized in that: in described step (1), and vibration isolator stiffness curve and vibration isolator load curve are determined by following formula:

$K\left(x\right)=\left\{\begin{array}{cc}\frac{{\mathrm{dk}}_0}{2}& x\≤x_0\\ \frac{{\mathrm{d\αe}}^{\frac{{\mathrm{\ω}}^2}{4{\mathrm{g\π}}^2}x}}{2}& x>x_0\end{array}\right.$

In formula, k₀For vibration isolator benchmark rigidity, d is vibration isolator arrangement pitch, and ω is system frequency, x₀For the static vertical basis displacement of floating plate.