CN114606807A - Vibration isolation structure for reducing railway vibration - Google Patents
Vibration isolation structure for reducing railway vibration Download PDFInfo
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- CN114606807A CN114606807A CN202210403208.2A CN202210403208A CN114606807A CN 114606807 A CN114606807 A CN 114606807A CN 202210403208 A CN202210403208 A CN 202210403208A CN 114606807 A CN114606807 A CN 114606807A
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- vibration
- railway
- isolator
- isolation structure
- vibration isolator
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
- E01B19/00—Protection of permanent way against development of dust or against the effect of wind, sun, frost, or corrosion; Means to reduce development of noise
- E01B19/003—Means for reducing the development or propagation of noise
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Abstract
The invention discloses a vibration isolation structure for reducing railway vibration, wherein a main body of the vibration isolation structure consists of a vibration isolator and a vibration isolation pad, the vibration isolator is arranged at a certain distance from a railway track and is discontinuously parallel to the railway direction, and the vibration isolation pad is positioned underground below the vibration isolator and is connected with the vibration isolator; the vibration isolator is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator is in a square shape of 3mx3m, the top surface of the vibration isolator is in a square shape of 1mx1m, and the step height is 15-25 cm; the thickness of the vibration isolator is 10-15cm, the height is 0.8-1m, and the length is 1-1.5 m. The vibration isolation structure for reducing railway vibration provided by the invention is composed of the continuous vibration isolation pad below the road surface and the vibration isolator above the road surface, and is more convenient in later maintenance due to the absence of the groove; and the vibration isolator is an independent individual, can be directly replaced when damaged, and cannot influence the long-term stability of other vibration isolators.
Description
Technical Field
The invention belongs to the technical field of building vibration isolation, and particularly relates to a vibration isolation structure for reducing railway vibration.
Background
Along with the rapid development and the large-scale large cities of the industry nowadays, the traffic demands of the cities are continuously increased, and the traffic problems are increasingly highlighted. The Jingjin intercity railway, Jingguang high-speed railway, Zheng Xigao railway, Shangning intercity high-speed railway, Shanghan high-speed railway, Jinghushi high-speed railway, Hada high-speed railway and Lanxin high-speed railway are successively opened and operated, the Chinese high-speed railway leads the rapid development of the high-speed railway all over the world, the speed is faster and faster, the rapid construction speed of the railway is increased in the development process, so that the vibration isolation measures of the following supporting facilities are not followed, and therefore surrounding buildings are influenced by the main vibration function and cannot delay the moment of the vibration of the railway environment.
Therefore, it has become a key problem to face in railway construction to take corresponding vibration reduction and isolation measures in the vicinity of the periphery of the railway line to reduce the adverse effects caused by railway operation. For vibration of railway transportation, the vibration source control, the vibration propagation control and the building self-control are mainly used for controlling the vibration source, the vibration propagation control and the building self-control. For the established railway lines and buildings, the control of vibration propagation becomes an extremely important means.
Vibration isolation gutters are a common engineering method to impede or alter the propagation of peripheral vibration waves to a shielded area, thereby reducing ground vibration in the shielded area. The principle of the vibration isolation groove is based on reflection and scattering of waves. When a propagating wave encounters an interface between two different elastic media, a part of the incident wave is reflected back to the first medium, and another part of the wave is transmitted to the second medium, which is the reflection and transmission phenomena of the elastic wave. The vibration isolation trench can also change the frequency distribution of waves, disperse the energy of the main frequency band of the waves and is beneficial to reducing the vibration effect of vibration. Since the vibration waves encounter different media in the ground, the greater the difference between the media, the more easily the vibration surface waves reflect and do not easily pass through the media interface. To stop the propagation of surface waves, measures may be taken to cut off the propagation path of the vibrations, i.e. to take the form of trenching in the formation.
In the prior art, the patent CN104674853B issued by the chinese patent office on 2016, 6, 8, is named as a vibration isolation trench, which is a structure that a trench body is dug in a roadbed and is arranged below a road, but the vibration isolation trench is not easy to maintain. Chinese patent CN109778919B discloses a vibration isolation dike for reducing vibration of railway environment, wherein a dike body is arranged on the ground at a certain distance from the railway line along the direction of the railway line, the cross section of the dike body is in a step shape, the material of the dike body is made of concrete, rubber, foam or other plastic materials, the dike body can be hollow, so as to save materials; in addition, the vibration isolation dikes may be arranged in a combination of a plurality of rows of dikes to further attenuate the transmission of vibration waves. However, the vibration isolation dike is arranged at the position of the railway toe, and the vibration isolation effect is limited in the established railway section without the toe. Meanwhile, the vibration isolation ditches and the vibration isolation dikes adopted in the prior art are continuously arranged along the railway direction, the overall stability is easily caused in the subsequent maintenance process, the long-term stability is not facilitated, and the maintenance work of the vibration isolation ditches with accumulated water is not easy.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a vibration isolation structure for reducing railway vibration, which is composed of a continuous vibration isolation pad below a road surface and a vibration isolator above the road surface, has a good vibration isolation effect, is convenient to build and is easy to maintain.
In order to achieve the purpose, the invention provides the following technical scheme:
a vibration isolation structure for reducing railway vibration is characterized in that a main body of the vibration isolation structure is composed of vibration isolators and vibration isolation pads, the vibration isolators are arranged at intervals in a direction parallel to a railway at a certain distance from a railway track, and the vibration isolation pads are positioned underground below the vibration isolators and are connected with the vibration isolators;
the vibration isolator is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator is 3mx3m square, the top surface of the vibration isolator is 1mx1m square, and the step height is 15-25 cm;
the thickness of the vibration isolator is 10-15cm, the height is 0.8-1m, and the length is 1-1.5 m.
Preferably, the vibration isolator material is concrete or foam material, and the vibration isolator material is rubber.
Preferably, the vibration insulators are at least one row.
Preferably, the distance between two adjacent vibration isolators is 3-4 m.
Preferably, the vibration isolator is continuously buried in the ground by splicing.
Preferably, the included angle between the inclined plane of the stepped quadrangular frustum pyramid shaped vibration isolator and the horizontal plane is 35-50 degrees.
Preferably, the vibration insulator is disposed at a distance of 5-8m from the railway track.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the vibration isolation structure for reducing railway vibration, the discontinuous vibration isolators are arranged along the railway direction, and then the vibration isolators are arranged into the stepped quadrangular pyramid shape, so that when vibration waves are transmitted, the vibration isolators can absorb the vibration waves transmitted from all directions, the energy of the vibration waves at each stepped corner point of the vibration isolators can be decomposed, and the energy of the vibration waves passing through the vibration isolators relative to the energy of initial incident waves is reduced. Meanwhile, the frequency distribution of the waves can be changed between two adjacent vibration isolators, the energy of the main frequency band of the waves is dispersed, and the vibration effect is favorably reduced.
(2) According to the vibration isolation structure for reducing the railway vibration, the continuous rubber vibration isolation pad is embedded below the vibration isolator by utilizing the 'water stop steel plate' principle in the field of buildings, so that the vibration isolation structure can play a role in blocking vibration waves transmitted underground; meanwhile, the vibration isolation pad is connected with the upper vibration isolator, so that vibration waves can be transmitted to the upper vibration isolator, and then the vibration effect is further reduced through the step corner of the vibration isolator.
(3) The vibration isolation structure for reducing railway vibration comprises the continuous vibration isolation pad below the road surface and the vibration isolator above the road surface, and is more convenient in later maintenance due to the absence of the groove; and the vibration isolator is an independent individual, can be directly replaced when damaged, and cannot influence the long-term stability of other vibration isolators.
Drawings
Fig. 1 is a schematic view of a vibration isolation structure for reducing railway vibration in embodiment 1 of the present invention;
FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;
fig. 3 is a schematic structural view of a vibration isolator in embodiment 1 of the present invention;
fig. 4 is a schematic view of the vibration isolation structure in comparative example 1 of the present invention.
Wherein, 1, railway pavement; 2. a vibration isolator; 3. a vibration isolator; 4. and (5) building the surroundings.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1 to 3, a vibration isolation structure for reducing railway vibration, the vibration isolation structure having a main body composed of vibration isolators 2 and vibration isolators 3, wherein the vibration isolators 2 are intermittently disposed at a distance from a railway track and in parallel with the railway direction, and the vibration isolators 3 are disposed underground under the vibration isolators 2 and connected to the vibration isolators 3;
the vibration isolator 2 is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator 2 is 3mx3m square, the top surface of the vibration isolator is 1mx1m square, and the step height is 15 cm;
the thickness of the vibration isolation pad 3 is 10cm, the height is 0.8m, and the length is 1 m.
In this embodiment, the vibration isolator material is concrete, and the vibration isolator material is rubber.
In this embodiment, the vibration isolators are in a row.
In the present embodiment, the distance between two adjacent vibration isolators is 3 m.
In this embodiment, the vibration isolator is continuously buried in the ground by splicing.
In this embodiment, an included angle between the inclined surface of the stepped quadrangular frustum pyramid shaped vibration isolator and the horizontal plane is 35 degrees.
In the present embodiment, the vibration insulator is disposed at a distance of 5m from the railway track.
According to the standard TBT 3152 and 2007 railway environment vibration measurement, when the position 20m away from the center of the track is monitored, the vibration response is reduced by 11dB, and the energy of train vibration can be effectively prevented and reduced from being transmitted to a building.
Example 2
The vibration isolation structure for reducing the railway vibration is characterized in that the main body of the vibration isolation structure is composed of vibration isolators 2 and vibration isolation pads 3, the vibration isolators 2 are arranged at intervals at a certain distance from a railway track and in a direction parallel to the railway, and the vibration isolation pads 3 are positioned underground below the vibration isolators 2 and are connected with the vibration isolators 3;
the vibration isolator 2 is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator 2 is 3mx3m square, the top surface of the vibration isolator 2 is 1mx1m square, and the step height is 25 cm;
the thickness of the vibration isolation pad 3 is 15cm, the height is 1m, and the length is 1.5 m.
In this embodiment, the vibration isolator material is a foam material, and the vibration isolator material is rubber.
In this embodiment, the vibration isolators are in a row.
In this embodiment, the distance between two adjacent vibration isolators is 3-4 m.
In this embodiment, the vibration isolator is continuously buried in the ground by splicing.
In this embodiment, an included angle between the inclined surface of the stepped quadrangular frustum pyramid shaped vibration isolator and the horizontal plane is 50 degrees.
In the present embodiment, the vibration insulator is disposed at a distance of 8m from the railway track.
According to the standard TBT 3152 and 2007 railway environment vibration measurement, vibration response is reduced by 12dB at a position 20m away from the center of a track, and the energy of train vibration can be effectively prevented and reduced from being transmitted to a building.
Comparative example 1
Referring to fig. 4, a vibration isolation structure for reducing railway vibration, the main body of which is composed of vibration isolators 2, the vibration isolators 2 being intermittently disposed at a distance from a railway track and parallel to the railway direction;
the vibration isolator 2 is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator 2 is 3mx3m square, the top surface of the vibration isolator 2 is 1mx1m square, and the step height is 15 cm.
In the present comparative example, the insulator material was concrete.
In this comparative example, the spacers are in a row.
In the present comparative example, the interval between two adjacent vibration insulators was 3 m.
In this comparative example, the inclined surface of the stepped quadrangular frustum pyramid shaped vibration isolator included an angle of 35 degrees with the horizontal plane.
In the present comparative example, the vibration insulator was disposed at a distance of 5m from the railway track.
According to the standard TBT 3152 and 2007 railway environment vibration measurement, vibration response is reduced by 7dB at a position 20m away from the center of the track, and the effect of blocking and reducing the energy of train vibration transmitted to a building is limited.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. The vibration isolation structure for reducing railway vibration is characterized in that a main body of the vibration isolation structure is composed of vibration isolators (2) and vibration isolation pads (3), the vibration isolators (2) are arranged at intervals in a certain distance from a railway track and in a direction parallel to the railway, and the vibration isolation pads (3) are positioned underground below the vibration isolators (2) and are connected with the vibration isolators (3);
the vibration isolator (2) is in a stepped quadrangular frustum pyramid shape, the bottom surface of the vibration isolator (2) is 3mx3m square, the top surface of the vibration isolator is 1mx1m square, and the step height is 15-25 cm;
the thickness of the vibration isolation pad (3) is 10-15cm, the height is 0.8-1m, and the length is 1-1.5 m.
2. The vibration isolation structure for reducing railway vibration according to claim 1, wherein the vibration isolator material is concrete or a foam material, and the vibration isolator material is rubber.
3. The vibration isolation structure for reducing railway vibration according to claim 1, wherein the vibration isolators are at least one row.
4. The vibration isolation structure for reducing railway vibration according to claim 1, wherein a distance between two adjacent vibration isolators is 3-4 m.
5. The vibration isolation structure for reducing railway vibration according to claim 1, wherein the vibration isolator is buried underground continuously by splicing.
6. The vibration isolation structure for reducing railway vibration according to claim 1, wherein the inclined surface of the stepped quadrangular frustum pyramid shaped vibration isolator forms an angle of 35 to 50 degrees with the horizontal plane.
7. The vibration isolation structure for reducing railway vibration according to claim 1, wherein the vibration isolator is disposed at a distance of 5-8m from a railway track.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115142481A (en) * | 2022-07-28 | 2022-10-04 | 武汉铁路职业技术学院 | Railway discontinuous vibration isolator |
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CN113107021A (en) * | 2021-04-20 | 2021-07-13 | 辽宁工程技术大学 | Vibration isolation dike for preventing vibration rebound increase of high-speed rail and arrangement method thereof |
CN213952310U (en) * | 2020-10-28 | 2021-08-13 | 黄淮学院 | Vibration isolation wall structure used in soil body |
CN214460680U (en) * | 2020-10-23 | 2021-10-22 | 天津大学 | Vibration isolation structure for mixed filler filling channel |
CN114197958A (en) * | 2021-12-10 | 2022-03-18 | 同济大学 | Inverted trapezoidal pile vibration isolation barrier and construction method thereof |
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2022
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DE19643533A1 (en) * | 1996-10-23 | 1998-04-30 | Krupp Ag Hoesch Krupp | Sound absorbing load-bearing gratings for railway track |
JP2006045787A (en) * | 2004-07-30 | 2006-02-16 | Penta Ocean Constr Co Ltd | Construction method of column row-type underground vibration-isolating wall |
CN101092831A (en) * | 2007-07-17 | 2007-12-26 | 广州大学 | Method for isolating vibration by using underground external wall of buildings |
CN103382725A (en) * | 2013-01-22 | 2013-11-06 | 刘方成 | Geocell reinforced rubber particles-sand mixture compound shock insulation layer and strip |
CN103967056A (en) * | 2014-04-21 | 2014-08-06 | 河海大学 | Junked tire vibration damping and isolating building foundation and construction method thereof |
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CN109778919A (en) * | 2019-03-25 | 2019-05-21 | 华东交通大学 | A kind of vibration isolation dike for reducing railway environment vibration |
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CN213952310U (en) * | 2020-10-28 | 2021-08-13 | 黄淮学院 | Vibration isolation wall structure used in soil body |
CN113107021A (en) * | 2021-04-20 | 2021-07-13 | 辽宁工程技术大学 | Vibration isolation dike for preventing vibration rebound increase of high-speed rail and arrangement method thereof |
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CN115142481A (en) * | 2022-07-28 | 2022-10-04 | 武汉铁路职业技术学院 | Railway discontinuous vibration isolator |
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