Prefabricated spliced ​​plate type ballastless track structure and construction method thereof

Abstract

The present invention provides a prefabricated spliced ​​plate type ballastless track structure and a construction method thereof, belonging to the technical field of railway tracks, comprising: a supporting layer, a ballast plate and two rails, wherein limited bosses are arranged at intervals on the supporting layer; the ballast plate comprises a filling layer and a prefabricated part arranged on the supporting layer in sequence from bottom to top; the prefabricated part comprises two prefabricated plates symmetrically arranged on both sides of the filling layer in the width direction and two rows of rail bearing platforms arranged on the two prefabricated plates, and an isolation wall is formed along the center line of the filling layer to isolate the two prefabricated plates, and the two prefabricated plates are connected as a whole by steel bars penetrating the isolation wall; the two rails are respectively arranged on the two rows of rail bearing platforms. The present invention has the advantages of high availability in tunnels and is suitable for the construction of tunnel railways and subway projects; it has the advantages of high smoothness, replaceable and maintainable ballast plates, controllable filling layer quality and low cost, and also has the advantages of low risk of cracks and separation on the contact surface of new and old concrete.

Description

Technical Field

[0001] The invention belongs to the technical field of railway tracks, and in particular relates to a prefabricated spliced ​​plate type ballastless track structure and a construction method thereof. Background Art

[0002] Due to the advantages of ballastless track, such as high smoothness, high stability and low maintenance, the track structures of newly built high-speed railways, passenger-dedicated railways, passenger-freight railways and urban (suburban) railways all use ballastless track structure. In addition, intercity lines and urban rail transit all adopt ballastless track structure.

[0003] The ballastless tracks mainly used at present can be divided into two categories: one is the slab ballastless track, such as the CRTS Ⅰ, CRTS Ⅱ and CRTS Ⅲ slab ballastless tracks used for high-speed railways and various prefabricated assembled integral roadbeds used for urban rail transit; the other is the sleeper (block) embedded ballastless track, such as the double-block ballastless track used for national railway lines and the long-sleeper embedded roadbed used for urban rail transit.

[0004] Slab ballastless track has high smoothness and sleeper (block) embedded ballastless track has good economy. They are well applied in track engineering, accounting for 49.5% and 50.5% of high-speed railway projects respectively. With the development of railways and the increase in the service time of existing ballastless tracks, the problems faced by traditional slab ballastless track and sleeper (block) embedded ballastless track are becoming increasingly prominent.

[0005] The main problems of traditional slab track are: (1) The CA mortar or self-compacting concrete filling layer under the track slab relies on the material's own fluidity to ensure the casting quality, resulting in limited controllability of the filling layer quality; (2) The cost of CA mortar and self-compacting concrete is relatively high, and the cost of using slab track is high; (3) As the service time increases, slab track is also prone to track slab separation and dynamic damage to the filling layer; (4) Due to the large track slab area of ​​slab track, the construction space is limited, laying in a single-line tunnel is inconvenient, and the construction applicability is poor.

[0006] The main problems of ballastless track with embedded sleepers (blocks) are: (1) The new and old concrete formed by cast-in-place concrete and prefabricated sleepers (blocks) are in continuous contact, and cracks around the contact surface are difficult to control; (2) After entering the service period, under the action of the large axle load of freight cars, cracks further develop on passenger and freight railways, especially the sleeper blocks will detach, affecting the stress performance and stability of the track structure; (3) Since the track smoothness depends on the installation accuracy of the sleeper (block) combined track, there are many factors that affect the realization of high track smoothness. Summary of the invention

[0007] The embodiment of the present invention provides a prefabricated spliced ​​slab ballastless track structure and a construction method thereof, which has the advantages of a slab ballastless track and a sleeper-embedded ballastless track, and can solve the problems of uncontrollable pouring quality of the slab ballastless track filling layer and difficult control of the construction accuracy of the sleeper-embedded ballastless track.

[0008] In the first aspect, in order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a prefabricated spliced ​​plate type ballastless track structure, comprising: a supporting layer, a ballast plate and two steel rails, and limited position bosses are arranged at intervals on the supporting layer; the ballast plate comprises a filling layer and a prefabricated part which are arranged on the supporting layer in sequence from bottom to top; the prefabricated part comprises two prefabricated plates symmetrically arranged on both sides of the filling layer in the width direction and two rows of rail supporting platforms arranged on the two prefabricated plates, and an isolation wall is formed along the center line of the filling layer to isolate the two prefabricated plates, and the two prefabricated plates are connected as a whole by steel bars passing through the isolation wall; the two steel rails are respectively arranged on the two rows of rail supporting platforms.

[0009] In combination with the first aspect, in one achievable manner, a plurality of embedded tubes are arranged at intervals in the prefabricated panel, and the steel bars are all penetrated through the embedded tubes.

[0010] In combination with the first aspect, in one achievable manner, an isolation layer is further provided between the support layer and the filling layer, and the isolation layer is any one of geotextile, rubber mat, and polyurethane mat.

[0011] In combination with the first aspect, in one achievable manner, the filling layer is cast in situ in the filling space between the prefabricated panel and the supporting layer.

[0012] In combination with the first aspect, in one achievable manner, both ends of the track bed plate in the length direction are respectively provided with limiting grooves that engage with the limiting bosses.

[0013] In combination with the first aspect, in one achievable manner, the limiting boss is a cylinder, which is integrally cast on the supporting layer.

[0014] In combination with the first aspect, in one achievable manner, the diameter of the limiting boss is smaller than the width of the isolation wall in the width direction.

[0015] In combination with the first aspect, in one achievable manner, the materials of the supporting layer, the filling layer and the prefabricated parts are all ordinary concrete.

[0016] In combination with the first aspect, in one achievable manner, the rail support platform is provided with a rail support groove for mounting the steel rail.

[0017] In a second aspect, an embodiment of the present invention further provides a construction method of a prefabricated spliced ​​plate type ballastless track structure, which is used to construct the prefabricated spliced ​​plate type ballastless track structure, and the construction method comprises:

[0018] Casting the supporting layer;

[0019] Laying an isolation layer on the supporting layer;

[0020] Placing a prefabricated component above the isolation layer and supporting it on all sides so that a filling space is formed between the prefabricated component and the supporting layer;

[0021] pouring ordinary concrete in the filling space to form a filling layer;

[0022] Inserting steel bars into the embedded pipes of the prefabricated parts, and passing the steel bars through the isolation wall on the filling layer, and performing post-tensioning construction to form a ballast slab;

[0023] The rails are fixed on the rail bearing platform of the track bed plate.

[0024] Compared with the prior art, the prefabricated spliced ​​plate type ballastless track structure and the preparation method thereof provided by the present invention have the following beneficial effects:

[0025] (1) The prefabricated spliced ​​slab ballastless track structure of the present invention inherits the characteristic of the sleeper (block) embedded ballastless track, which is convenient for construction in tunnels, and solves the problem of low availability of the current traditional slab ballastless track in single-track tunnels.

[0026] (2) The prefabricated spliced ​​slab ballastless track structure of the present invention has the characteristics of high usability in tunnels and high smoothness of slab ballastless track, which solves the problem that the construction accuracy of the buried sleeper (block) ballastless track is difficult to control, thereby reducing the problem of line unevenness.

[0027] (3) The prefabricated spliced ​​plate ballastless track structure provided by the present invention inherits the advantage of the embedded ballastless track with sleepers (blocks) in that it is easy to construct in tunnels. In addition, due to the existence of an isolation layer between the prefabricated parts and the lower supporting layer, the prefabricated parts are replaceable and maintainable, thus solving the problem that the embedded ballastless track with sleepers (blocks) is difficult to replace and maintain.

[0028] (4) The under-slab cast material of the prefabricated spliced ​​slab ballastless track structure provided by the present invention can be manually vibrated at the location of the isolation wall, thereby solving the problem of uncontrollable quality caused by the under-slab cast material of the traditional slab ballastless track that needs to rely on its own fluidity to ensure density.

[0029] (5) The prefabricated spliced ​​slab ballastless track structure provided by the present invention can be cast using ordinary concrete as the material. Compared with the casting material of the traditional slab ballastless track, the price is lower, thus solving the problem of the high cost of the current slab ballastless track.

[0030] (6) In the prefabricated spliced ​​plate ballastless track structure provided by the present invention, prestressed steel bars can be used to strengthen the anchoring between the prefabricated parts and the cast-in-place filling layer, effectively reducing the risk of structural defects such as cracks and separation at the contact surface between the new and old concrete, and solving the problem of cracks at the contact surface between the new and old concrete of the existing sleeper (block) embedded ballastless track. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic structural diagram of a prefabricated spliced ​​plate type ballastless track structure provided in an embodiment of the present invention (plate end of the track bed plate);

[0032] Figure 2 A schematic structural diagram of a prefabricated spliced ​​plate ballastless track structure provided by an embodiment of the present invention (a transverse cross-sectional view of a limiting boss along a supporting layer);

[0033] Figure 3 A schematic diagram of the main structure of a prefabricated spliced ​​plate type ballastless track structure provided in an embodiment of the present invention;

[0034] Figure 4 A schematic diagram of a top view of a prefabricated spliced ​​plate ballastless track structure provided in an embodiment of the present invention;

[0035] Description of reference numerals:

[0036] 1. Support layer; 11. Limiting boss; 2. Isolation layer; 3. Filling layer; 31. Isolation wall; 4. Embedded pipe; 5. Prefabricated part; 51. Prefabricated plate; 52. Rail support platform; 6. Rail. DETAILED DESCRIPTION

[0037] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] Please also read Figures 1 to 4 , the prefabricated spliced ​​plate type ballastless track structure provided by the present invention is now described. The prefabricated spliced ​​plate type ballastless track structure comprises: a supporting layer 1, a ballast plate and two rails 6, and the supporting layer 1 is provided with limited bosses 11 at intervals; the ballast plate comprises a filling layer 3 and a prefabricated part 5 sequentially arranged on the supporting layer 1 from bottom to top; the prefabricated part 5 comprises two prefabricated plates 51 symmetrically arranged on both sides of the width direction of the filling layer 3 and two rows of rail support platforms 52 arranged on the two prefabricated plates 51, and an isolation wall 31 is formed along the center line of the filling layer 3 to isolate the two prefabricated plates 51, and the two prefabricated plates 51 are connected as a whole by steel bars penetrating the isolation wall 31; the two rails 6 are respectively arranged on the two rows of rail support platforms 52.

[0039] Among them, the prefabricated part 5 is limited between two adjacent limiting bosses 11, and the limiting bosses 11 limit the length direction of the track bed plate; wherein, the length direction of the track bed plate is the extension direction of the track, and a number of prefabricated parts 5 are laid in the length direction of the track, and an adjustment gap is left between two adjacent prefabricated parts 5.

[0040] A plurality of rail support platforms 52 are arranged at intervals along the extension direction of the track on each prefabricated panel 51, wherein the rail support platforms 52 and the prefabricated panels 51 can be fastened together by embedded bolts or embedded anchors, and are manufactured in a prefabrication factory to form prefabricated components 5. After being transported to the construction site, they are hoisted as a whole and spliced ​​with the filling layer 3 to reduce the time occupied at the construction site. Therefore, the prefabricated components 5 can be prepared by reasonably arranging the construction period, thereby reducing the on-site construction period and shortening the construction time.

[0041] Compared with the prior art, the prefabricated spliced ​​plate type ballastless track structure and the preparation method thereof provided by the present invention have the following beneficial effects:

[0042] (1) The prefabricated spliced ​​slab ballastless track structure of the present invention comprises a prefabricated slab 51 and a prefabricated rail support 52, inheriting the characteristic of the embedded sleeper (block) ballastless track, which is convenient for construction in tunnels, and solving the problem of low availability of the current traditional slab ballastless track in single-track tunnels.

[0043] (2) The prefabricated spliced ​​slab ballastless track structure of the present invention has strong usability in tunnels. Since the roadbed plate is made of prefabricated parts, it also has the characteristics of high smoothness of the slab ballastless track, which solves the problem that the construction accuracy of the buried ballastless track with sleepers (blocks) is difficult to control, thereby reducing the problem of line unevenness.

[0044] (3) The prefabricated spliced ​​plate ballastless track structure provided by the present invention inherits the advantage of the embedded ballastless track with sleepers (blocks) in that it is easy to construct in a tunnel. In addition, due to the existence of an isolation layer 2 between the prefabricated part 5 and the lower supporting layer 1, the prefabricated part 5 is replaceable and maintainable, thereby solving the problem that the embedded ballastless track with sleepers (blocks) is difficult to replace and maintain.

[0045] (4) The prefabricated spliced ​​slab ballastless track structure provided by the present invention is cast under the slab, and since there is a gap between the two prefabricated slabs in the width direction, the vibrating tool can extend into the cast-in-place concrete through the gap between the prefabricated slabs, and the cast-in-place concrete can be manually vibrated, thereby solving the problem of uncontrollable quality caused by the traditional slab ballastless track slab casting material relying on its own fluidity to ensure density.

[0046] (5) The prefabricated spliced ​​slab ballastless track structure provided by the present invention can be cast under the slab using ordinary concrete, which is cheaper than the self-compacting casting material of the traditional slab ballastless track, thus solving the problem of the high cost of the current slab ballastless track.

[0047] (6) In the prefabricated spliced ​​plate ballastless track structure provided by the present invention, prestressed steel bars can be used to strengthen the anchoring between the prefabricated parts 5 and the cast-in-place filling layer 3, effectively reducing the risk of structural defects such as cracks and separation at the contact surface between the new and old concrete, and solving the problem of cracks at the contact surface between the new and old concrete of the existing sleeper (block) embedded ballastless track.

[0048] In some embodiments, see Figures 1 to 4 As shown, a plurality of embedded pipes 4 are arranged at intervals in the precast panel 51, and steel bars are inserted in the embedded pipes 4. Specifically, at least two embedded pipes 4 are arranged at intervals in each section of the track bed along the extension direction of the track, and are embedded in the precast panel 51 during prefabrication. When the filling layer 3 is cast in situ, the embedded pipes 4 can be cast in the isolation wall 31 at the location of the isolation wall 31 of the filling layer 3, thereby improving the firmness of the splicing of the precast member 5 and the cast-in-situ filling layer 3.

[0049] In some embodiments, see Figures 1 to 3 As shown, an isolation layer 2 is also provided between the supporting layer 1 and the filling layer 3. The isolation layer 2 is made of a material that can meet the isolation performance requirements, and the isolation layer 2 includes but is not limited to any one of geotextile, rubber pad, and polyurethane pad. Because there is an isolation layer 2 between the prefabricated part 5 and the lower supporting layer 1, the prefabricated part 5 is replaceable and maintainable, which solves the problem that it is difficult to replace and maintain the sleepers (blocks) of the buried ballastless track.

[0050] In some embodiments, see Figures 1 to 4 As shown, the filling layer 3 is cast in situ in the filling space between the precast panel 51 and the supporting layer 1. During the casting, the precast panel 51 is supported by a guard plate around it, and a bracket is arranged between the precast panel 51 and the supporting layer 1 (specifically, the isolation layer 2), so that a filling space is formed between the precast panel 51 and the supporting layer 1. After ordinary concrete is cast in the filling space, since there is a gap between the precast panels 51 on both sides of the width direction, a vibrating device can be used to extend into the concrete in the filling space for manual or electric vibration, thereby improving the compactness of the filling layer 3. This does not require the concrete's own fluidity, thus avoiding the problem of uncontrollable quality caused by concrete with its own fluidity, and does not require the use of high-priced concrete materials with good self-fluidity for filling, thereby reducing the price of the concrete materials used, and thus greatly reducing the construction cost.

[0051] The upper surface of the filling layer 3 is flush with the upper surface of the prefabricated plate 51 .

[0052] In some embodiments, see Figures 1 to 4 As shown, limiting grooves engaging with the limiting bosses 11 are respectively provided at both ends of the track bed plate in the length direction.

[0053] In some embodiments, see Figure 3 to Figure 4 As shown, the limiting boss 11 is a cylinder, which is integrally cast on the supporting layer 1. The limiting boss 11 can also be a polygonal column, and the corresponding limiting groove is a multi-deformation groove.

[0054] In some embodiments, see Figure 4 As shown, the diameter of the limiting boss 11 is smaller than the width of the isolation wall 31 in the width direction. The width direction is the width direction of the track perpendicular to the length direction of the track.

[0055] In some embodiments, the materials of the supporting layer 1, the filling layer 3 and the prefabricated parts 5 are all ordinary concrete.

[0056] In some embodiments, see Figure 4 As shown, the rail support platform 52 is provided with a rail support groove for installing the rail 6. The rail 6 is fixed on the rail support platform 52 by a rail fastener.

[0057] Explain that ordinary concrete refers to artificial stone made of cement as the main cementitious material, mixed with water, sand, gravel, and chemical admixtures and mineral admixtures when necessary, in appropriate proportions, after uniform mixing, compacting, forming, curing and hardening. Concrete is mainly divided into two stages and states: the plastic state before coagulation and hardening, that is, fresh concrete or concrete mixture; the hard state after hardening, that is, hardened concrete or concrete.

[0058] Self-compacting concrete (SCC) refers to concrete that can flow and compact under its own gravity, can completely fill the formwork even with dense steel bars, and has good homogeneity, and does not require additional vibration. Disadvantages: The durability of self-compacting concrete after hardening is very limited, especially in cold climates; at the same time, there are unstable bubbles in self-compacting concrete. High-flow self-compacting concrete has a slightly larger drying shrinkage than ordinary concrete.

[0059] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0060] Based on the same inventive concept, the present application also provides a construction method for a prefabricated spliced ​​plate type ballastless track structure, which is used to construct the prefabricated spliced ​​plate type ballastless track structure, see Figures 1 to 4 As shown, the construction method comprises:

[0061] Casting a supporting layer 1 on the foundation, wherein the length of the supporting layer 1 cast at one time may be n times the length of the ballast plate, where n is a positive integer greater than or equal to 1; wherein a certain telescopic adjustment gap is also provided between the supporting layers 1;

[0062] An isolation layer 2 is laid on the support layer 1; after the construction of the support layer 1 is completed, the isolation layer 2 is laid on the upper surface of the support layer 1;

[0063] The prefabricated member 5 is set up on the isolation layer 2 and supported on all sides, so that a filling space is formed between the prefabricated member 5 and the supporting layer 1; wherein the prefabricated member 5 is positioned and adjusted by related instruments including but not limited to a total station, a prism, etc., to ensure the horizontality of the two prefabricated members 5 in the width direction and the accuracy of positioning;

[0064] Ordinary concrete is poured into the filling space to form a convex filling layer 3, and the protruding portion between the two prefabricated panels 51 is defined as a partition wall 31; wherein the embedded pipe 4 is poured into the filling layer 3;

[0065] The steel bars are inserted into the embedded pipe 4 of the prefabricated part 5, and the steel bars are passed through the isolation wall 31 on the filling layer 3, and the post-tensioning construction is performed to form the track bed slab;

[0066] The rails 6 are fixed to the rail support 52 of the track bed plate by rail fasteners.

[0067] The prefabricated spliced ​​plate type ballastless track structure provided by the present invention has the following beneficial effects:

[0068] (1) It has the advantage of high availability in tunnels and is suitable for tunnel railway and subway construction.

[0069] (2) It has the advantage of high smoothness.

[0070] (3) The track bed plate is replaceable and maintainable.

[0071] (4) The quality of the filling layer 3 can be controlled.

[0072] (5) It has the advantage of low cost.

[0073] (6) It has the advantage of low risk of cracks and separation at the contact surface between new and old concrete.

[0074] Post-tensioning method is a road engineering term: [post-tensioning method] Post-tensioning method refers to a construction method of pouring concrete first, and then tensioning prestressed steel to form prestressed concrete components after the concrete reaches more than 75% of the design strength.

[0075] Specifically: first make the component (pour concrete), and reserve corresponding channels in the component body according to the position of the prestressed tendons. After the concrete strength of the component reaches the specified strength (generally not less than 75% of the design strength standard value), insert the prestressed tendons into the reserved channels for tensioning, and use anchors to anchor the tensioned prestressed tendons at the ends of the component. Relying on the anchors at the ends of the component, the prestressing force of the prestressed tendons is transmitted to the concrete, causing it to generate precompression stress. Finally, cement slurry is poured into the channels to form a whole with the prestressed tendons and the concrete component.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A prefabricated spliced ​​plate type ballastless track structure, characterized in that: include: A supporting layer (1) on which limited position bosses (11) are arranged at intervals; A ballast plate, comprising a filling layer (3) and a prefabricated component (5) arranged on the supporting layer (1) in order from bottom to top; the prefabricated component (5) comprises two prefabricated panels (51) symmetrically arranged on both sides of the filling layer (3) in the width direction and two rows of rail support platforms (52) arranged on the two prefabricated panels (51); a separation wall (31) is formed along the center line of the filling layer (3) to separate the two prefabricated panels (51); the two prefabricated panels (51) are connected as a whole by steel bars penetrating the separation wall (31); and Two steel rails (6) are respectively arranged on two rows of rail support platforms (52); The construction method for constructing the prefabricated spliced ​​plate type ballastless track structure includes: Casting a supporting layer (1); Laying an isolation layer (2) on the support layer (1); A prefabricated component (5) is installed above the isolation layer (2) and supported on all sides, so that a filling space is formed between the prefabricated component (5) and the supporting layer (1); Ordinary concrete is poured in the filling space to form a convex filling layer (3), and the protruding portion between the two prefabricated panels (51) is defined as a partition wall (31); Inserting steel bars into the embedded pipe (4) of the prefabricated part (5), and passing the steel bars through the isolation wall (31) on the filling layer (3), and performing post-tensioning construction to form a trackbed slab; The steel rail (6) is fixed on the rail support platform (52) of the track bed plate.

2. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: A plurality of embedded pipes (4) are arranged at intervals in the prefabricated plate (51), and the embedded pipes (4) are all penetrated by the steel bars.

3. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: An isolation layer (2) is also provided between the supporting layer (1) and the filling layer (3), and the isolation layer (2) is any one of geotextile, rubber mat and polyurethane mat.

4. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: The filling layer (3) is cast in situ in the filling space between the prefabricated panel (51) and the supporting layer (1).

5. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: Both ends of the track bed plate in the length direction are respectively provided with limiting grooves which engage with the limiting bosses (11).

6. The prefabricated spliced ​​plate type ballastless track structure according to claim 1, characterized in that: The limiting boss (11) is a cylinder and is integrally cast on the supporting layer (1).

7. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: The diameter of the limiting boss (11) is smaller than the width of the isolation wall (31) in the width direction.

8. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: The materials of the supporting layer (1), the filling layer (3) and the prefabricated component (5) are all ordinary concrete.

9. The prefabricated spliced ​​plate ballastless track structure according to claim 1, characterized in that: The rail support platform (52) is provided with a rail support groove for mounting the steel rail (6).

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