CN209873457U

CN209873457U - Ballastless track structure

Info

Publication number: CN209873457U
Application number: CN201920140090.2U
Authority: CN
Inventors: 张千里; 陈锋; 王鹏程; 李中国; 张新冈; 尧俊凯; 崔颖辉; 刘景宇; 刘振宇; 曾帅
Original assignee: China Academy of Railway Sciences Corp Ltd CARS; Railway Engineering Research Institute of CARS
Current assignee: China Academy of Railway Sciences Corp Ltd CARS; Railway Engineering Research Institute of CARS
Priority date: 2019-01-25
Filing date: 2019-01-25
Publication date: 2019-12-31
Anticipated expiration: 2029-01-25

Abstract

The utility model provides a ballastless track structure, ballastless track structure includes by lower supreme ground, road bed and the supporting layer of laying, and this ballastless track structure still includes: a bearing layer disposed between the supporting layer and the roadbed, and a bearing pile having one end inserted into the foundation and one end fixedly connected with the bearing layer to support the bearing layer in balance from below. The track structure effectively reduces the influence of foundation expansion on the track structure elevation and prolongs the time interval of twice track elevation adjustment.

Description

Ballastless track structure

Technical Field

The utility model relates to a track structure especially relates to a ballastless track structure.

Background

When the high-speed railway in China is rapidly developed, due to the influence of the expansion effect of roadbed filling or a foundation soil layer in a track structure, certain high-speed railway adopting a ballastless track structure has arch-up diseases, in order to ensure the operation safety, speed-limiting measures have to be taken, and the normal operation of the high-speed railway is seriously influenced.

In the existing treatment technology, when the track is found to have an upwarp disease due to the expansion of soil body roadbed filling or foundation soil, a method of excavating the roadbed or foundation with the thickness equal to the upwarp quantity can be adopted and then the elevation of the track structure is reduced for treatment, and the method effectively and thoroughly treats the upwarp of the track structure. However, the above adjustment method has a large amount of work and a high cost, and is not suitable for a soil foundation in the case of continuous deformation of the foundation or the roadbed, because frequent excavation of the roadbed or the foundation may seriously affect the stability and safety of the track structure and the normal operation of the train.

Therefore, a track structure facilitating elevation adjustment is urgently needed.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a ballastless track structure, its influence that the inflation that alleviates or offset road bed or ground caused through setting up bearer layer, bearing pile and buffer layer.

The utility model provides a ballastless track structure, it includes by lower supreme ground, road bed, the supporting layer of laying, characterized by still includes: a bearing layer disposed between the bearing layer and the subgrade, the bearing layer having a compressive strength and a stiffness greater than that of the bearing layer; and the bearing pile has one end inserted into the foundation and one end fixedly connected with the bearing layer so as to support the bearing layer from the lower part in a balanced manner, and the compressive strength and the rigidity of the bearing pile are both greater than those of the roadbed. The track structure effectively reduces the influence of foundation expansion on the track structure elevation and prolongs the time interval of twice track elevation adjustment.

Preferably, the ballastless track structure further comprises a buffer layer, the buffer layer is arranged between the bearing layer and the roadbed, the compression strength and the rigidity of the buffer layer are not higher than those of the roadbed, and the elastic modulus of the buffer layer is smaller than that of the roadbed.

Preferably, the ballastless track structure comprises at least two bearing piles, and the bearing piles are separately arranged on two lateral sides below the bearing layer.

Preferably, the load-bearing pile is constructed as a hollow structure.

Preferably, the track structure further comprises anchor lines anchored at one end to the foundation deeper than the load-bearing piles, and at the other end extending out of the load-bearing layer through the load-bearing piles and connected to the load-bearing layer by means of tensioning structures.

Preferably, the bearing layer is a slab of reinforced concrete.

Preferably, the buffer layer is a polystyrene foam plate or an extruded polystyrene foam plate.

Preferably, the bearing pile is a reinforced concrete pile and/or a steel pile.

Drawings

Fig. 1 is a schematic view of a ballastless track structure according to the present invention.

List of reference numerals

1. A support layer;

2. a carrier layer;

3. a buffer layer;

4. a roadbed;

5. a foundation;

6. carrying piles;

7. and (5) anchor cables.

Detailed Description

Referring now to the drawings, illustrative aspects of the disclosed structure will be described in detail. Although the drawings are provided to present embodiments of the invention, the drawings are not necessarily to scale of particular embodiments, and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the disclosure of the present invention.

Certain directional terms used hereinafter to describe the drawings, such as "upper", "lower", "lateral", "bottom", will be understood to have their normal meaning and refer to those directions as normally contemplated by the drawings. Unless otherwise indicated, the directional terms described herein generally refer to conventional directions as understood by those skilled in the art.

A conventional ballastless track structure generally includes a foundation 5 arranged from bottom to top, a roadbed 4 filled with crushed stones or the like, a support layer 1 generally cast with concrete (the support layer 1 is also referred to as a bed plate when made of reinforced concrete), a track slab generally cast with reinforced concrete, sleepers fixed in the track slab, and a track.

In order to reduce the influence of the soil expansion of the underlying foundation 4 or foundation 5 on the upper track structure, the supporting layer 1 and its overlying structure can be isolated from the underlying foundation 4 and foundation 5, whereby the track structure of the invention further comprises a carrier layer 2, as shown in fig. 1. The support layer 2 is arranged between the ballast bed 4 and the support layer 1, the upper surface of which preferably directly contacts the underside of the support layer 1 facing the ballast bed 4. The compressive strength and stiffness of the carrier layer 2 are designed to be at least greater than the compressive strength and stiffness of the support layer 1. The bearing layer 2 is generally made of C40 reinforced concrete material, and can be prefabricated or cast on site.

In order to better transfer the load experienced on the load bearing layer 2 to the underlying soil mass while enhancing the stability of the track structure, the track structure is further provided with load bearing piles 6 which may be fixedly connected (e.g. hingedly connected) to the load bearing layer 2. The load-bearing piles 6 are arranged below the load-bearing layer 2 (when the load-bearing layer 2 is a prefabricated slab) or through it (when the load-bearing layer 2 is cast in situ) to support it. Wherein the compressive strength and the rigidity of the load-bearing pile 6 are designed to be greater than those of the roadbed 4.

Preferably, more than two load-bearing piles 6 are used, which are arranged at least separately on the lateral sides below the load-bearing layer 2 to provide balanced support for the upper load-bearing layer 2 as required, so as to ensure balanced stability of the load-bearing layer 2. The load-bearing piles 6 can be inserted into the track structure below the supporting layer 1 by drilling, hammering, pressing, etc., and are inserted at least a distance into the foundation 5 in order to ensure the stability of the structure above. The load-bearing piles 6 may also be arranged in the corresponding foundations 5 below the shoulders or lines of the railway. Without limiting the shape and configuration of the load-bearing pile 6, it may be round, square or solid or hollow. The bearing pile 6 can be a reinforced concrete pile or a steel pile. Meanwhile, the bearing piles 6 can be arranged in an encrypted manner according to the stress condition of the bearing layer 2 and the material selected by the bearing piles 6. When the bearing layer 2 is supported by the bearing piles 6, a part of gaps can be reserved between the roadbed 4 and the bearing layer 2, so that more space is reserved for soil expansion, and the effect of the soil on the bearing layer 2 is relieved.

Preferably, anchor lines 7 may be provided in the same number as the load bearing piles 6 or in a smaller number than the load bearing piles 6 to increase the anchoring force of the load bearing piles 6. Preferably, the anchor cable 7 may be arranged such that: holes are punched into the ground 5 at the locations of the load piles 6 that are to be used in conjunction with the anchor lines 7, into which holes the anchor lines 7 are inserted and fixed relative to the ground 5 by means of grouting or the like, wherein the depth of insertion of the anchor lines 7 into the ground 5 is greater than or, as required, substantially greater than the depth of insertion of the load piles 6 into the ground 5.

Preferably, in case the load bearing pile 6 is of hollow construction, for example using hollow steel pipes, the load bearing layer 2 may be cast around the load bearing pile 6 or the load bearing pile 6 may be inserted into the load bearing layer 2, preferably without the upper end of the load bearing pile 6 protruding above the upper surface of the load bearing layer 2. The anchor lines 7 can be passed through the hollow interior of the load-bearing pile 6 until they project out of the upper load-bearing layer 2, while they are tensioned and fixed to the upper surface of the load-bearing layer 2 by means of tensioning devices, such as anchor head structures or the like.

Additionally, the utility model discloses buffer layer 3 is still provided in order to offset the inflation volume of the soil body and/or reduce the influence that soil body inflation deformation caused. The buffer layer 3 is preferably arranged between the roadbed 4 and the carrier layer 2, and its thickness can be set as required according to the expansion characteristics of the soil body. The compressive strength and the rigidity of buffer layer 3 are all not greater than road bed 4, the elastic modulus of buffer layer 3 is less than road bed 4, preferably adopt polystyrene foam board (EPS board) or extruded polystyrene foam (XPS board). Therefore, when the buffer layer 3 is extruded by soil expansion, a certain deformation amount is generated firstly, so that the expansion amount of the soil below is offset, when the buffer layer is deformed to a certain degree, the buffer layer 3 generates cracks under the action of the soil expansion force and is crushed, and the process is a process of releasing the soil expansion force. Simultaneously, the buffer layer 3 can also fill the gap between the bearing layer 2 and the roadbed 4, so that the requirement of the track structure on compactness is better met, and better support is provided for the upper track structure.

In addition, the active adjustment of the track elevation by means of the anchor cables 7 can be realized through the structure. When the elevation of the track is found to be increased, the anchor cables 7 exposed out of the bearing layer 2 can be further tensioned to press the bearing layer 2 downwards, so that the buffer layer 3 is actively crushed, the expansion force of the soil body is released, and the elevation of the track is adjusted downwards.

Claims

1. The utility model provides a ballastless track structure, includes by lower ground (5) of supreme laying, road bed (4), supporting layer (1), characterized by still includes:

a load-bearing layer (2) arranged between the supporting layer (1) and the roadbed (4), the load-bearing layer (2) having a compressive strength and a stiffness which are both greater than the compressive strength and the stiffness of the supporting layer (1);

one end of the bearing pile (6) is inserted into the foundation (5), one end of the bearing pile is fixedly connected with the bearing layer (2) so as to support the bearing layer (2) in a balanced manner from the lower part, and the compressive strength and the rigidity of the bearing pile (6) are both greater than those of the roadbed (4);

the buffer layer, it arranges the bearer layer with between the road bed, the compressive strength and the rigidity of buffer layer are all not higher than the compressive strength and the rigidity of road bed, the elastic modulus of buffer layer is less than the elastic modulus of road bed.

2. The ballastless track structure of claim 1, wherein at least two of said load-bearing piles are provided, said load-bearing piles being separately disposed at both lateral sides below said load-bearing layer.

3. The ballastless track structure of claim 2 wherein said load-bearing pile is configured as a hollow structure.

4. The ballastless track structure of claim 3, further comprising anchor lines, one end of which is anchored deeper to the foundation than the load-bearing piles, and the other end of which extends out of the load-bearing layer through the load-bearing piles and is connected to the load-bearing layer by means of a tensioning device.

5. The ballastless track structure of claim 1, wherein the bearing layer is a slab of poured reinforced concrete.

6. The ballastless track structure of claim 1, wherein the buffer layer is made of polystyrene foam board or extruded polystyrene foam plastic board.

7. The ballastless track structure of claim 1, wherein the bearing pile is a reinforced concrete pile and/or a steel pile.