Concrete sleeper for preventing ice and snow splashing on high-speed railway

Abstract

The application provides a concrete sleeper for preventing and treating ice and snow splashing of high-speed railway, which comprises a sleeper body and a dumbbell-shaped rail support platform arranged on the concrete sleeper body, and the sleeper body is designed in a horn shape along the running direction of the line. The bottom short shaft of the dumbbell-shaped rail support platform is the same as the width of the sleeper, the top is arranged with a steel rail and a fastener system, and the dumbbell-shaped rail support platform is designed in a streamlined shape with a narrow middle part and wide two ends. The concrete sleeper can increase the distance between the train bottom plate and the top surface of the track bed on the basis of maintaining the lateral stability of the track bed, increase the overall space of the wind field through the innovative design of the structure, and reduce the damage of the train caused by the ice and snow hitting the train bottom plate.

Description

Technical Field

[0001] This invention relates to the field of railway concrete sleeper technology, and in particular to a concrete sleeper for preventing ice and snow splashing on high-speed railways. Background Technology

[0002] High-speed rail, as a green, convenient, safe and efficient mode of transportation, occupies an important position in the comprehensive transportation system and promotes the rapid development of society and economy.

[0003] Judging from the construction and operation of high-speed railways, among the high-speed railway lines that have been opened and put into operation in my country, those with a design speed of 200 to 250 km / h mainly use ballasted track, and some sections of high-speed railway lines with a speed of 300 km / h and above also use ballasted track.

[0004] In international high-speed railway operations, ballasted track accounts for as much as 70%. In particular, Japan, France, and Germany, the three original countries of high-speed rail, have achieved maximum operating speeds of 300 km / h, 320 km / h, and 280 km / h respectively using ballasted track. In 2007, the French TGV train even set a world record of 574.8 km / h using ballasted track. From the perspective of domestic and international development trends, ballasted track in high-speed railways has greater advantages in applicability, flexibility, economy, and maintainability, possessing enormous development potential and becoming one of the main structural forms for my country's future high-speed railways.

[0005] With the large-scale operation of my country's high-speed railways, some new problems have gradually emerged. Ballast splashing is prone to occur when ballasted track trains exceed 300 km / h. In extremely cold regions, due to snow accumulation and ice melting on high-speed trains, ballast splashing can occur even at speeds of 200 km / h or lower. Ice and snow issues have a certain impact on the operation and development of high-speed railways. The main hazards caused by ice and snow splashing include: under conditions of train dynamics or temperature changes (such as crossing different regions, passing through tunnels or stations), ice and snow particles attached to the train body fall at high speed onto the tracks, causing ballast to rebound and splash, resulting in impacts to the carriage floor and trackside equipment, seriously threatening train operation safety.

[0006] Currently, both domestically and internationally, methods such as spraying ballast adhesive are used to fix ballast. However, there are disadvantages such as difficulty in maintenance and repair after spraying, and the formation of a whole after spraying, which increases rigidity and may cause increased ice rebound force.

[0007] Therefore, how to design a concrete sleeper that can effectively prevent ice and snow splashing on high-speed railways is an urgent problem to be solved. Summary of the Invention

[0008] Embodiments of the present invention provide a concrete sleeper for preventing ice and snow splashing on high-speed railways, so as to effectively reduce the hazards of ballast splashing caused by ice and snow impact.

[0009] To achieve the above objectives, the present invention adopts the following technical solution.

[0010] A concrete sleeper for preventing ice and snow splashing on high-speed railways includes a sleeper body and a dumbbell-shaped rail support. The dumbbell-shaped rail support is disposed on the concrete sleeper body, and the sleeper body has a funnel-shaped opening design along the running direction of the line.

[0011] Preferably, the bottom short axis of the dumbbell-shaped rail support platform is the same width as the sleeper, and the rail and fastening system are arranged on the top. The dumbbell-shaped rail support platform is designed with a streamlined shape that is narrow in the middle and wide at both ends.

[0012] Preferably, the dumbbell-shaped rail support platform has a height of 30-60mm, and both the upper and lower layers are elliptical in shape with an area ratio of approximately 1:3. The top major axis is 300mm and the minor axis is 180mm, while the bottom major axis is 500mm and the minor axis is 320mm. The dumbbell-shaped rail support platform is connected to the rail using fasteners, and the rail is fixed to the dumbbell-shaped rail support platform by the clamping action of the fasteners.

[0013] Preferably, for different rail and vehicle factors, a high-speed train-ballast track-wind field coupled simulation model is constructed using the DEM-MBD-CFD coupled analysis method. The model is used to simulate the ice falling off at the bottom of the middle of the car under the most unfavorable conditions, hitting the top of the track bed and causing ballast splashing. The number of ballast splashes hitting the train floor plate under different sizes is calculated, and curve fitting is performed to optimize the design of concrete sleepers.

[0014] Preferably, four small holes are symmetrically opened near the top surface of the track bed along the center line of the track along the running direction of the concrete sleeper. Each small hole is located on both sides below the two dumbbell-shaped rail bearing platforms. The shape of the small holes is optimized according to the flow field analysis model, and a trumpet shape with a thin middle and thick sides and a uniform transition is adopted.

[0015] Preferably, a computational fluid dynamics software is used to establish a flow field analysis model for ballast splashing on high-speed railway ballasted tracks. The wind pressure variation at the orifice location is extracted using the flow field analysis model for ballast splashing on high-speed railway ballasted tracks, and the orifice shape and size under different conditions are compared and analyzed.

[0016] As can be seen from the technical solutions provided by the embodiments of the present invention above, the present invention provides a concrete sleeper for preventing ice and snow splashing on high-speed railways. While maintaining the lateral stability of the track bed, it increases the distance between the train floor and the top surface of the track bed. Through innovative structural design, it increases the overall space of the wind field, reducing damage to the train floor caused by ballast splashing from ice and snow. The present invention uses the same raw materials, construction process, and design parameters as ordinary concrete sleepers; it achieves good protection against ice and snow splashing hazards simply through innovative design of its external dimensions, demonstrating good technical and economic efficiency.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A front view of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided by the present invention;

[0020] Figure 2 A top view of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided by the present invention;

[0021] Figure 3 A side view of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided by the present invention;

[0022] Figure 4 Detailed diagram of the opening shape of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided for the present invention.

[0023] Figure 5 A flow field model diagram for calculating the dimensional parameters of a concrete sleeper used to prevent ice and snow splashing on a high-speed railway, provided by the present invention.

[0024] Figure 6 A discrete element model diagram for calculating the dimensional parameters of a concrete sleeper used to prevent ice and snow splashing on high-speed railways, provided by the present invention.

[0025] Figure 7 A calculation and analysis diagram of the dimensional parameters of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided by the present invention;

[0026] In the diagram, 1. rail, 2. dumbbell-shaped rail support, 3. opening, 4. sleeper body, 5. high-speed train, 6. track structure, 7. ballast bed. Detailed Implementation

[0027] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0028] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or couplings. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0029] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0030] To facilitate understanding of the embodiments of the present invention, the following will provide further explanation and description with reference to the accompanying drawings and several specific embodiments. These embodiments do not constitute a limitation on the embodiments of the present invention.

[0031] This invention provides a concrete sleeper for preventing ice and snow splashing on high-speed railways. While ensuring the stability of the track bed, it reduces the possibility of ice and snow splashing impacting the carriage floor, thus ensuring the safe and stable operation of high-speed trains in frigid regions.

[0032] A front view of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided in an embodiment of the present invention, is shown below. Figure 1 As shown, the top view is as follows Figure 2 As shown, the side view is as follows Figure 3As shown. It includes: rail 1, dumbbell-shaped rail support 2, opening 3 and sleeper body 4. The dumbbell-shaped rail support 2 is set on the concrete sleeper body 4, and the sleeper body 4 has a trumpet-shaped opening design along the running direction of the track.

[0033] In the embodiments provided by the present invention, such as Figure 1 As shown, the dumbbell-shaped rail support 2 is directly cast onto the concrete body. A refined coupled model of high-speed train-ballast track-wind field is constructed using the DEM-MBD-CFD (Discrete Element Method-Multibody Dynamics-Computational Fluid Dynamics) coupled analysis method. The dimensions of the dumbbell-shaped rail support of the concrete sleeper of this invention are optimized using the refined coupled model of high-speed train-ballast track-wind field. The height of the concrete sleeper is 30-60mm, and both the upper and lower layers are elliptical with an area ratio of approximately 1:3. The major axis of the top is 300mm and the minor axis is 180mm, ensuring good placement of the rails and fasteners. The rail support is connected to the rails using fasteners. The rails are fixed to the rail support through the clamping action of the fasteners, maintaining the track gauge and preventing longitudinal and lateral movement of the rails. The major axis of the bottom is 500mm and the minor axis is 320mm, ensuring good bottom bearing capacity.

[0034] In the embodiments provided by the present invention, such as Figure 2 As shown, the bottom short axis of the dumbbell-shaped rail support platform 2 is the same width as the sleeper, and the area above the top can be used to arrange the rails and fastening system. Furthermore, the dumbbell-shaped rail support platform 2 is designed with a streamlined shape that is narrow in the middle and wide at both ends. This ensures that when a high-speed train passes, there are no large undulations or sharp edges at the location of the dumbbell-shaped rail support platform 2, resulting in little or no turbulence. This minimizes air resistance at the rail support platform location and is more conducive to preventing ballast from splashing and impacting.

[0035] A detailed diagram of the opening shape of a concrete sleeper for preventing ice and snow splashing on high-speed railways, provided by this invention, is shown below. Figure 4 As shown. Figure 4As shown, four small holes are symmetrically opened near the top surface of the ballast bed along the track centerline, along the direction of track operation. Each hole is located on either side below the two dumbbell-shaped rail supports 2. The shape of the holes is optimized based on a flow field analysis model, adopting a "trumpet" shape that is thinner in the middle and thicker at both ends with a uniform transition. The minimum radius is 50mm, and the maximum radius is 70mm, to better reduce aerodynamic effects. A computational fluid dynamics (CFD) model of ballast splash flow in high-speed railway ballasted tracks is established. This model is used to extract wind pressure changes at the hole locations. A comparative analysis of the hole shape and size under different conditions shows that the presence of the holes allows some of the wind generated by passing trains to escape. The holes enhance airflow and ensure circulation, thereby reducing the aerodynamic effect between the carriage floor and the top of the ballast bed. This reduces the wind load on the ballast stirred up by ice fragments, further minimizing the damage.

[0036] By raising the height of the sleeper support platform 2, the distance between the bottom of the train and the top surface of the track bed is increased. This increases the rebound distance of ballast splashed by ice blocks hitting the track bed under icy and snowy conditions, reducing the possibility of ballast hitting the train floor and minimizing damage to the carriage structure, thus better ensuring the safe operation of high-speed railways under icy and snowy conditions.

[0037] The concrete sleeper of this invention can be designed for different factors such as rails and vehicles. A three-dimensional model reflecting its true dimensions is established. Using a DEM-MBD-CFD coupled analysis method, a refined simulation model of the high-speed train-ballast track-wind field coupling under corresponding conditions is constructed using computational fluid dynamics, multibody dynamics, and discrete element analysis software. The ballast track DEM module serves as an intermediary, the MBD module applies train dynamic loads to the sleeper structure, and the CFD module applies train wind field effects. A coupled parallel algorithm enables data transfer of momentum, mass, and force information between the three modules. The model simulates the most unfavorable condition where ice falls from the bogie at the bottom center of the carriage, impacting the top of the track bed and causing ballast to splash and hit the train floor. The number of ballast splashes hitting the train floor under different dimensions is calculated, and curve fitting is performed for optimization design.

[0038] The dumbbell-shaped support platform 2 in this embodiment of the invention can be designed as a groove, which can better utilize the fastening performance of the fastener.

[0039] The dumbbell-shaped rail support platform 2 of this invention has a height of 30-60mm. This height range can meet the needs of different sleeper types, track grades, and track gauges in different sections and curved sections. Furthermore, the concrete sleepers used in this invention use the same raw materials as ordinary concrete sleepers, and the material properties and construction process of the dumbbell-shaped rail support platform are also largely the same, ensuring that its load-bearing strength and track stability are comparable to ordinary concrete sleepers, resulting in good technical and economic efficiency.

[0040] The flow field model diagram for calculating the dimensional parameters of a concrete sleeper used to prevent ice and snow splashing on high-speed railways, provided in this embodiment of the invention, is shown below. Figure 5 As shown, the discrete element model diagram for calculating the dimensional parameters is as follows. Figure 6 As shown in the diagram, the analysis of the dimensional parameter value calculation is as follows: Figure 7 As shown.

[0041] Figure 5 This paper presents a flow field analysis model for a high-speed train on a ballasted track, established using Computational Fluid Dynamics (CFD) software. The computational domain has a total length of 400m, a width of 80m, and a height of 50m, mainly comprising two parts: a moving computational domain for the high-speed train and a fixed computational domain for the track structure. Based on the sliding mesh technique, the initial distance between the nose of the train and the horizontal direction of the track is 20m, and the train travels along the positive direction of the track centerline. After the train leaves the track, the distance between the nose of the tail train and the horizontal direction of the track is 20m, thus effectively simulating the wind field effect of the high-speed train on the ballasted track and obtaining good flow data.

[0042] Figure 6 This is a discrete element simulation model of a ballasted track structure, mainly consisting of rails, dumbbell-shaped rail supports, sleepers, and ballast track. It belongs to the DEM module and is mainly used as an intermediate medium to simulate the ice and snow splashing process.

[0043] Figure 7 The distribution curves of the number of splashed ballasts at the same train speed under different rail platform heights, calculated using the DEM-MBD-CFD coupled analysis method, show that as the rail platform height increases, the number of splashed ballasts exceeding the rail position decreases significantly. When the height reaches 30mm, the number of splashed ballasts is below 10, which is at a low level. When it reaches or exceeds 60mm, there are almost no splashed ballasts exceeding the rail position, having virtually no impact on normal train operation. Curve fitting using a nonlinear function yields the following results: Figure 7 Based on the results shown, it is recommended that the height of the rail support platform be 30–60 mm.

[0044] In summary, the embodiments of the present invention, by casting dumbbell-shaped rail support platforms on the sleeper body, increase the distance from the bottom of the carriage to the top of the track bed. This reduces the likelihood of ballast splashing from ice and snow impacting the track bed and striking the train floor, thus avoiding serious damage to the train floor. Simultaneously, the perforated design of the sleeper body reduces aerodynamic effects. Furthermore, it meets the requirements for safe and stable operation of high-speed railways and provides technical reserves and support for the development of ballast track structures for high-speed railways in frigid regions of my country, demonstrating strong practical value.

[0045] This invention can reduce the aerodynamic response at the sleeper location during train operation, providing a solution for preventing ballast splashing on high-speed railways under icy and snowy conditions. It reduces the probability of ice forming and falling off the bogie location under icy and snowy conditions, impacting the track bed and causing ballast splashing that could damage the train. At the same time, it ensures the load-bearing strength of the sleepers and the good stability of the track, effectively avoiding the operational risks caused by ballast splashing and ensuring the safe and stable operation of trains.

[0046] This invention provides a concrete sleeper for preventing ice and snow splashing on high-speed railways. Considering aerodynamic effects, dumbbell-shaped rail bearing platforms are cast at both ends of the concrete sleeper body at the rail bearing grooves, raising the position of the rails and increasing the height of the train floor above the track surface. Funnel-shaped holes are also made at the front and rear of the concrete sleeper body to maintain good airflow in this area when the train passes at high speed. Using the DEM-MBD-CFD coupled analysis method, a refined coupled model of high-speed train-ballast track-wind field is constructed, and the dimensions of this concrete sleeper are optimized.

[0047] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0048] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for apparatus or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the description of the method embodiments. The apparatus and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0049] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A concrete sleeper for preventing ice and snow splashing on high-speed railway, characterized in that, The rail support body and the dumbbell-shaped rail support platform are provided on the concrete rail support body, and the rail support body is designed in a trumpet shape along the line running direction; A three-dimensional model reflecting the real size of different steel rails and vehicles is established, and a DEM-MBD-CFD coupling analysis method is used to build a high-speed train-ballasted track-wind field coupling refined simulation model under corresponding conditions by using computational fluid dynamics, multi-body dynamics and discrete element analysis software. Through the DEM module of the ballasted track as an intermediate medium, the MBD module is used to apply the train dynamic load to the sleeper structure, and the CFD module is used to apply the train wind field effect. Relying on the coupling parallel algorithm, the momentum, mass and stress information data transmission between the three modules is realized. The high-speed train-ballasted track-wind field coupling refined simulation model is used to simulate the ice falling off at the bogie position at the middle bottom of the car under the most unfavorable conditions, and the ballast splashing hits the train bottom plate. The number of ballast splashing hitting the train bottom plate under different sizes is calculated, and curve fitting is performed for optimization design; The concrete sleeper is provided with four small holes near the top surface of the track bed along the line running direction, which are symmetrically arranged along the line center line, and each small hole is located below the two sides of the dumbbell-shaped rail support platform. According to the flow field analysis model, the shape of the small hole is optimized and designed as a trumpet shape with a thin middle and thick edges, and the minimum radius is 50 mm and the maximum radius is 70 mm. A high-speed railway ballasted track ballast splashing flow field analysis model is established by using computational fluid dynamics software. The wind pressure variation at the position of the small hole is extracted by using the high-speed railway ballasted track ballast splashing flow field analysis model, and the shape and size of the small hole under different conditions are compared and analyzed. A high-speed train-ballasted track flow field analysis model is established by using computational fluid dynamics (CFD) software. The total length of the calculation region of the high-speed train-ballasted track flow field analysis model is 400 m, the width is 80 m, and the height is 50 m. The high-speed train-ballasted track flow field analysis model includes a high-speed train moving calculation domain and a track structure fixed calculation domain. Based on the analysis method of the sliding mesh technology, at the initial time, the train nose tip is 20 m away from the track in the horizontal direction and moves along the track center line in the positive direction. When the train moves away from the track, the tail nose tip is 20 m away from the track in the horizontal direction, and the wind field effect of the high-speed train-ballasted track is simulated. The height of the dumbbell-shaped rail supporting platform is 30-60 mm, the upper and lower layers are both arranged in an elliptical shape, the area ratio is 1:3, the long axis of the top is 300 mm, the short axis is 180 mm, the long axis of the bottom is 500 mm, and the short axis is 320 mm, the dumbbell-shaped rail supporting platform is connected with the rail by using a fastener, the rail is fixed on the dumbbell-shaped rail supporting platform through the clamping effect of the fastener, the height range of the dumbbell-shaped rail supporting platform meets the requirements of the line in different sections and curve sections according to different sleeper types, different line grades and different track gauge lines, the DEM-MBD-CFD coupling analysis method is used to calculate the distribution curve of the number of flying ballast under the same vehicle speed under different dumbbell-shaped rail supporting platform heights, and the number of flying ballast heights exceeding the rail position decreases with the increase of the height of the rail supporting platform.

2. The concrete tie of claim 1, wherein The bottom short axis of the dumbbell-shaped rail supporting platform is the same as the sleeper width, the rail and the fastener system are arranged above the top, and the dumbbell-shaped rail supporting platform is designed in a streamlined shape with a narrow middle part and wide ends.

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