RU2814899C1 - Vibration isolating base of superstructure of subway track - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to the field of railway track structure in tunnels, in particular, to the subway track superstructure vibration isolating bases. Base comprises multiple transverse support plates with rail supports. Plates are installed on vibration isolators. Each transverse support plate comprises a rectangular narrow part connected to an expanding trapezoidal part connected to a rectangular wide part. Rectangular narrow part of each support plate is installed so that it is in contact with two rectangular wide parts of adjacent transverse support plates. Under rectangular narrow part on longitudinal axis there is one vibration isolator, and under rectangular wide part at equal distance in longitudinal axis there are two vibration isolators. Vibration isolators are located on two parallel longitudinal lines at the same longitudinal distance from each other.

EFFECT: reduced intensity of vibration from passing rolling stock.

13 cl, 5 dwg, 1 tbl

Description

DESCRIPTION OF THE INVENTION

The technical field to which the invention relates.

The invention relates to devices for the superstructure of a subway track, in particular to a vibration-isolating base for the superstructure of a subway track [E01B1/00, F16F7/00, E02D31/08].

State of the art.

The upper track structure is a part of the railway track, which includes rails, fastenings, under-rail supports (for example, sleepers) and other elements, for example, vibration isolators, designed to accept loads from the wheels of the rolling stock and transfer them to the lower track structure, as well as to direct the movement of wheels along the rail track.

DAMPING DEVICE FOR SUBWAY TRACKS WITH TRANSVERSE DAMPING FUNCTION [CN218561958U, publ. 03.03.2023], containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators, each transverse support plate has a rectangular shape, the transverse support plates are interconnected, and the vibration isolators are located on two parallel longitudinal lines on there are two vibration isolators at the same distance from each other in the longitudinal axis under one rail.

BALLAST-FREE RAILWAY TRACK FOR HIGH-SPEED FREIGHT AND PASSENGER TRAFFIC AND METHOD OF ITS CONSTRUCTION [RU2755804C1, publ. 09.21.2021], containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators in the form of polymer plates, the size corresponding to the dimensions of the transverse support plates, with each transverse support plate having a rectangular shape.

REPAIRABLE DAMPING SYSTEM FROM PREFABRICATED STEEL SPRING FLOATING PLATES [CN203475236U, publ. 03/12/2014], containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators, each transverse support plate having a rectangular shape, and the vibration isolators located on two parallel longitudinal lines at the same distance from each other in the longitudinal axles with two or three vibration isolators under one rail.

The disadvantage of analogues and the prototype is the high level of vibration due to the distribution of horizontal transverse forces on one transverse base plate, due to the use of a rectangular slab shape, which does not allow the distribution of loads from rolling stock to adjacent slabs, ensuring uniform distribution and reducing the amplitude of vibration of the slabs in response on the application of loads from rolling stock.

Disclosure of the invention

The technical problem to be solved by the claimed invention is the creation of a vibration-isolating base for the superstructure of a subway track with a reduced vibration level.

The technical result is to increase the vibration-isolating properties of the base and reduce the intensity of vibration when rolling stock passes along the superstructure of the track.

The specified technical result is objectively manifested in a reduction in the level of vibration that occurs when rolling stock passes along the superstructure of the track.

The specified technical result provides a vibration-isolating base of the superstructure of a subway track, containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators, with each transverse support plate containing a rectangular narrow part connected to an expanding trapezoidal part connected to a rectangular wide one part, and the transverse support plates are connected so that the rectangular narrow part of one support plate is in contact with two rectangular wide parts of adjacent transverse support plates, while one vibration isolator is placed under the rectangular narrow part on the longitudinal axis, and under the rectangular wide part at an equal distance in the longitudinal axis two vibration isolators are placed on the axis so that the vibration isolators in the vibration isolating base of the superstructure of the subway track are located on two parallel longitudinal lines at the same distance from each other in the longitudinal axis.

In particular, the transverse base plate is made of reinforced concrete.

In particular, the length and width of the rectangular narrow part are proportionally equal to the length and width of the rectangular wide part.

Specifically, the length of the rectangular narrow portion of the transverse support plate is equal to the length of the rectangular wide portion of the transverse support plate, and the width of the rectangular narrow portion of the transverse support plate is equal to half the width of the rectangular wide portion of the transverse support plate.

In particular, vibration isolators are made in the form of springs or plates.

In particular, the transverse support plate is supported by vibration isolators by means of set screws.

In particular, the transverse support plates are rigidly attached to the vibration isolators with a grouting composition, for example, a non-shrinking, quick-hardening mixture.

In particular, elastic formwork is installed between the slabs and vibration isolators.

In particular, the plates are connected by fastenings.

In particular, every fourth transverse support plate has a hole in the center.

In particular, six under-rail supports are placed on the plate, four supports are located on the rectangular wide part and two supports are located on the rectangular narrow part.

In particular, the rail supports are at the same distance from each other in the longitudinal axis.

In particular, elastic seals are located between the transverse support plates.

Brief description of drawings

In fig. 1 shows a top view of the transverse support plate of the claimed vibration-isolating base of the superstructure of a subway track.

In fig. Figure 2 shows a cross-section of the slab from Figure 1 along plane A-A with rails installed on the vibration-isolating base of the superstructure of the subway track.

In fig. Figure 3 shows a general view of the vibration-isolating base of the superstructure of the subway track.

In fig. Figure 4 schematically shows the horizontal lateral forces generated by the rolling stock in one of the transverse support plates.

In fig. Figure 5 shows a general view of the vibration-isolating base of the superstructure of a subway track, known from the prior art.

The figures indicate: 1 – transverse support plate, 2 – vibration isolator, 3 – lower track structure, 4 – rectangular narrow part, 5 – expanding trapezoidal part, 6 – rectangular wide part, 7 – under-rail support, 8 – track rail, 9 – fastening the contact rail bracket, 10 – contact rail bracket, 11 – contact rail, 12 – fastening unit, 13 – set screw, 14 – mounting hole, 15 – elastic formwork, 16 – hole.

Implementation of the invention.

In this application, the lower track structure means a monolithic or prefabricated flat rigid base in the tunnel tray.

The longitudinal axis of the path is understood as a line passing through the center of the path and directed along its length.

The longitudinal direction of the slab means the direction that runs along the length of the transverse base plate.

By transverse direction is meant a direction perpendicular to the longitudinal direction.

By vertical forces from rolling stock we mean forces that arise from the weight of the rolling stock, the weight of the crew (these forces are constant), as well as from vibrations on the springs, from track unevenness and unevenness on the wheels.

Longitudinal forces from rolling stock are understood as forces that act along the direction of train movement, arising due to the interaction of wheels with rails, acceleration and braking of rolling stock, and unevenness on the rails or wheels.

Horizontal shear forces from rolling stock refer to forces that act perpendicular to the movement of the train. Horizontal lateral forces increase when the train moves in curved sections of the track due to centrifugal forces and the directing force acting on the first axes of the train's bogies, which tend to continue moving in a straight line, but the rail laid along the curve forces the wheel pair to turn.

The vibration-isolating base of the upper track structure contains prefabricated transverse support plates 1, each of which has vibration isolators resting on the lower track structure 3.

The transverse support plate 1 is made of reinforced concrete. The transverse support plate 1 contains three successive parts: a rectangular narrow part 4, a flared trapezoidal part 5, a rectangular wide part 6. The flared trapezoidal part 5 has a trapezoidal shape in the top view, and the rectangular parts 4 and 6 have a rectangular shape in the top view, as shown in fig. 1 and 3.

The narrow/wide characteristics used in the present description are relative, not absolute, and are interpreted only in relation to each other, so the narrow part has a smaller width than the wide part, and vice versa. By the width of a part is meant the size of the part in the transverse direction of the base plate, by the length of the part is meant the size of the part in the longitudinal direction of the base plate.

Preferably, the length of the rectangular narrow part 4 is equal to the length of the rectangular wide part 6, and the width of the rectangular narrow part 4 is equal to half the width of the rectangular wide part 6.

The assembled transverse support plates 1 are arranged in such a way that one transverse support plate 1 is adjacent to the rectangular narrow part 4 with the rectangular wide part 6, and the wide part 6 is adjacent to the rectangular narrow part 4 of the adjacent transverse support plate 1, as shown in Fig.3.

The shape of the transverse support plate 1 ensures uniform distribution of horizontal transverse forces across several plates from the rolling stock, due to the presence of a rectangular narrow part 4 and a rectangular wide part 6 and their alternation in assembled form. Each transverse support plate 1 rests on vibration isolators 2, which are, for example, metal springs or plates made, for example, of polymer materials. Each transverse support plate 1 is preferably supported by three vibration isolators 2, preferably one in the center of the rectangular narrow part 4 and two under the rectangular wide part 6. Moreover, the distance between the vibration isolators 2 is designed in such a way that the vibration isolators in the longitudinal axis are located at equal distances from each other . In particular, vibration isolator 2 under the rectangular narrow part 4 is located on the central axis of the transverse support plate 1, and two vibration isolators 2 under the rectangular wide part 6 are removed in the longitudinal axis at a distance equal to the length of the rectangular narrow part 4.

For use in the subway, fastenings 9 are made on the upper surface of the transverse support plate 1 to secure the brackets of the contact rail 10 with the possibility of installing the contact rail 11 using the fastening unit 12. In this case, the fastenings 9 are located in such a way that two are located along the rectangular wide part 6 and one located in the middle of the rectangular narrow part 4.

The transverse support plate 1, by means of, for example, set screws 13, has the ability to adjust the position for installation in the design position, and is also rigidly fixed to the vibration isolators 2 by filling the mounting holes 14 with a grout composition, for example, a non-shrinking quick-hardening mixture.

Between the transverse support plate 1 and the vibration isolator 2, an elastic form 15 is installed, which prevents the leakage of the grout composition and ensures constant sealing of the gap between the plate 1 and the vibration isolator 2 during the process of adjusting the position of the transverse support plate 1 to the design marks.

The transverse support plates 1 are connected to each other by fastenings, which can be pre-installed or installed at the time of installation. Between the transverse support plates 1, elastic seals are preferably located, which are rubber or silicone bands. Every fourth transverse support plate 1 has a hole 16 in the center with a preferred size of at least 400×600 mm to allow cleaning and inspection of the drainage tray.

The overall dimensions of the transverse support plate 1 are preferably 2170 mm along the track axis by 3400 mm across the track axis. The thickness of the transverse support plate 1 in the under-rail section is preferably 350 mm.

Vibration isolators 2 rest on the lower base 3 of the track, located at a slope of, preferably, 3‰ to the longitudinal axis, regardless of the curvature of the track section. A longitudinal drainage tray is formed in the lower structure of track 3.

On the plate 1 there are under-rail supports 7, preferably six under-rail supports, in such a way that four supports 7 are located on the rectangular wide part 6 at the same distance from each other and two supports 7 are located on the rectangular narrow part 4, also at the same distance from each other . The under-rail supports 7 are configured to provide support for the track rails 8.

The vibration-isolating base of the track superstructure is used as follows.

When rolling stock passes along the upper track structure, vertical, longitudinal and transverse forces arise due to the interaction of wheels with rails, resulting from vibrations of the body on springs, unevenness on the track, wobbling of the train, acceleration and braking. The emergence of these forces leads to the appearance of vibration oscillations. During operation, vibration isolators, for example steel springs or polymer plates, dampen vibration vibrations transmitted from the upper track structure to the lower one through the claimed device due to compression and stretching of the vibration isolators.

Justification of the technical result.

The technical result - reducing the level of vibration when rolling stock passes along the superstructure of the track is achieved by reducing vibration vibrations. The reduction of vibration vibrations can be divided into the damping of vertical, longitudinal forces and horizontal transverse forces transmitted from the rolling stock and the superstructure to the substructure.

Since these forces are associated with the interaction of wheels with rails, acceleration and braking of rolling stock, unevenness on rails or wheels, their absorption is achieved by absorbing vibration energy by vibration isolators and converting this energy into heat.

The damping of lateral forces also occurs due to the absorption of vibration energy by vibration isolators and the conversion of this energy into thermal energy.

The transverse support plates are shaped as a rectangular narrow part, a flared trapezoidal part, and a rectangular wide part. For slabs, the length of the rectangular narrow part is equal to the length of the rectangular wide part, and the width of the rectangular narrow part is equal to half the width of the rectangular wide part, which makes it possible to fasten the slabs in the longitudinal axis, alternating the orientation of the slabs so that one slab with a rectangular narrow part is adjacent to the rectangular wide parts of neighboring ones slabs, and the rectangular wide part adjoins the rectangular narrow parts of neighboring slabs.

As a result, the claimed vibration-isolating base of the superstructure of the track has sections in which, on one transverse straight line, there are two rectangular wide parts of two adjacent slabs, which makes it possible to transfer transverse forces from one slab to the two adjacent ones through the touching expanding trapezoidal parts (see Fig. 3) .

In addition, as a result, each slab is associated with two other slabs in the transverse direction, which allows the three adjacent slabs to work together (as shown in Fig. 4), distributing the loads from the rolling stock onto the three adjacent slabs, ensuring uniformity of distribution and reducing the amplitude of vibration of the slabs in response to applied loads from rolling stock. Whereas with the rectangular shape of the slabs known from the prior art, the horizontal transverse forces are distributed only on one slab (see Fig. 5).

There are three vibration isolators under each base plate. Despite the odd number, due to their location: under the rectangular narrow part on the central axis of the slab, and under the rectangular wide part, two vibration isolators are removed in the longitudinal axis at a distance of the length of the rectangular narrow part; in the longitudinal axis and on parallel lines, equidistance of the vibration isolators is ensured, which leads to to uniform distribution and damping of vertical, longitudinal and transverse forces. Vibration isolators are located at the vertices of an isosceles triangle, providing complete coverage in the horizontal plane to absorb horizontal shear forces.

The distance between vibration isolators is uniform along the length and minimal in distance, since this reduces bending moments in the slab. With the proposed dimensions, the maximum bending moments occur during installation of the slab, and not under the rolling stock. In this case, the height (thickness) of the slab is minimal, which ensures its compact placement in the cross section of the tunnel.

The option of trapezoidal slabs was considered, but the angles of the side faces are relatively small, which leads to an increase in the forces acting on the seals between the joints of the slabs from longitudinal and horizontal transverse forces.

Elastic seals located between the transverse support plates additionally absorb and dissipate vibration energy, thereby increasing the vibration-isolating properties of the base and reducing the level of vibration during the passage of rolling stock.

Examples.

To quantitatively assess the increase in the vibration-isolating properties of the proposed design during the passage of rolling stock, an experiment was conducted to measure the level of vibration accelerations that occur when the rolling stock passes along the superstructure of the track. A vibrometer with three-axis accelerometers was used as a device for measuring vibration accelerations. For the experiment, rolling stock was launched at a speed of 70 km/h along the superstructure of the track with the test vibration-isolating bases of the superstructure of the subway track and at the same points (on the under-rail support and on the tunnel lining at a level of 1.2 m from the level of the rail heads), measured using vibrometer levels of vibration accelerations for a standard and vibration-isolating base of the superstructure of a subway track. The results obtained are shown in Table 1.

The following were used as a test vibration-isolating base for the superstructure of the subway track:

- vibration-isolating base of the upper structure of the subway track, containing a plurality of transverse support blocks on which single under-rail supports are placed and which are installed on single vibration isolators under each block (A);

- vibration-isolating base of the upper structure of the subway track, containing a monolithic rectangular base plate on which under-rail supports are placed and which is installed on a plurality of vibration isolators placed in two lines in pairs, symmetrically relative to the axis of the track (B);

- the superstructure of a subway track without a vibration-isolating base (B);

- a vibration-isolating base of the superstructure of a subway track, containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators, each transverse support plate containing a rectangular narrow part connected to an expanding trapezoidal part connected to a rectangular wide part, and the transverse support plates are connected so that the rectangular narrow part of one support plate is in contact with two rectangular wide parts of adjacent transverse support plates, while one vibration isolator is placed under the rectangular narrow part on the longitudinal axis, and under the rectangular wide part at an equal distance from the axis of symmetry of the support plate two vibration isolators are placed so that the vibration isolators in the vibration isolating base of the superstructure of the subway track are located on two parallel longitudinal lines at the same distance from each other in the longitudinal axis (D);

- a vibration-isolating base for the superstructure of a subway track, which differs from the base G in that it additionally has elastic seals in the form of tapes (D).

Table 1 - Obtained values of reduction on the lining of the equivalent level of vibration accelerations when rolling stock passes through the superstructure, measured with a vibrometer, compared with a standard design without vibration isolators, dBa

Parameter Base A B IN G D Reduction of the equivalent level of vertical vibration accelerations on the tunnel lining, compared to the standard structure of the track superstructure (B) 9.8 19.2 0.0 15.6 16.1 Reduction of the equivalent level of horizontal vibration accelerations on the tunnel lining, compared with the standard design of the superstructure of the track (B) -6.2 -1.5 0.0 10.2 10.3 Note: the sign “-” means negative efficiency in vibration transmission compared to a typical subway design (B)

The data obtained indicate that the transverse support plate contains a rectangular narrow part connected to an expanding trapezoidal part connected to a rectangular wide part, and the transverse support plates are connected so that the rectangular narrow part of one support plate is in contact with two rectangular wide parts of adjacent transverse support plates, ensures uniform distribution of horizontal transverse, vertical and longitudinal forces. Placing vibration isolators on two parallel longitudinal lines at equal distances from each other in the longitudinal axis so that there is one vibration isolator under the rectangular narrow part on the longitudinal axis, and two vibration isolators under the rectangular wide part at an equal distance in the longitudinal axis, provide complete coverage in the horizontal plane for damping horizontal shear forces.

Claims (13)

1. A vibration-isolating base of the superstructure of a subway track, containing a plurality of transverse support plates on which under-rail supports are placed and which are installed on a plurality of vibration isolators, wherein each transverse support plate contains a rectangular narrow part connected to an expanding trapezoidal part connected to a rectangular wide part, wherein the transverse support plates are connected so that the rectangular narrow part of one support plate is in contact with two rectangular wide parts of adjacent transverse support plates, while one vibration isolator is placed under the rectangular narrow part on the longitudinal axis, and one vibration isolator is placed under the rectangular wide part at an equal distance in the longitudinal axis two vibration isolators so that the vibration isolators in the vibration isolating base of the superstructure of the subway track are located on two parallel longitudinal lines at the same distance from each other in the longitudinal axis. 2. The base according to claim 1, in which the transverse support plate is made of reinforced concrete. 3. The base according to claim 1, in which the length and width of the rectangular narrow part are proportionally equal to the length and width of the rectangular wide part. 4. The base according to claim 1, in which the length of the rectangular narrow part of the transverse base plate is equal to the length of the rectangular wide part of the transverse base plate, and the width of the rectangular narrow part of the transverse base plate is equal to half the width of the rectangular wide part of the transverse base plate. 5. The base according to claim 1, in which the vibration isolators are made in the form of springs or plates. 6. The base according to claim 1, in which the transverse support plate rests on vibration isolators using set screws. 7. The base according to claim 1, in which the transverse support plates are rigidly attached to the vibration isolators with a grouting composition, for example, a non-shrinking, quick-hardening mixture. 8. The base according to claim 1, in which elastic formwork is installed between the slabs and vibration isolators. 9. The base according to claim 1, in which the plates are connected by fasteners. 10. The base according to claim 1, in which every fourth transverse support plate has a hole in the center. 11. The base according to claim 1, in which six under-rail supports are placed on the plate, four supports are located on the rectangular wide part and two supports are located on the rectangular narrow part. 12. The base according to claim 1, in which the under-rail supports are located at the same distance from each other in the longitudinal axis. 13. The base according to claim 1, in which elastic seals are located between the transverse support plates.