A ballast splash wind tunnel test platform

Abstract

The embodiment of the present invention provides a ballast splash wind tunnel test platform, including: a ballast splash test bench, a test bench bracket, a high-speed train car bottom structure model, a sleeper model, a rail model, a ballast shoulder model, ballast aggregate and a wind speed test device; the ballast splash test bench is connected and fixed to the high-speed train car bottom structure model and the wind tunnel laboratory floor respectively through the test bench bracket, the test bench bracket is height-adjustable, the sleeper model is placed on the ballast aggregate surface, the ballast aggregate is placed on the ballast splash test bench surface, the rail model is fixed to the top surface of the sleeper model bearing rail groove, the ballast shoulder model is fixed to both sides of the sleeper model and the ballast aggregate, and the wind speed test device is fixed to the ballast aggregate surface between the sleeper model. The present invention can accurately simulate the occurrence conditions of high-speed railway ballast splash, restore the occurrence and development characteristics of ballast splash, and can monitor the ballast splash flow field data in real time, and is easy to operate.

Description

Technical Field

[0001] The invention relates to the technical field of rail transit, and in particular to a ballast splash wind tunnel test platform. Background Art

[0002] High-speed railways are an important part of the modern transportation system. As an important part of high-speed railways, tracks play an indispensable role in ensuring the safe and smooth operation of trains. Among them, ballasted tracks have significant advantages in applicability, flexibility, economy and maintainability, and are one of the main track structures of high-speed railways. Among the high-speed railway lines that have been opened and operated in my country, almost all high-speed railways formed by the transformation of existing lines use ballasted tracks. High-speed railways in the newly built lines with an operating speed of 250km / h mainly use ballasted tracks. Some sections of high-speed railway lines with an operating speed of 300km / h and above also use ballasted tracks, especially in special sections such as long bridges, elevated stations, and geological fault zones. Ballasted track structures have to be used.

[0003] In recent years, with the gradual increase in train speed, ballast particles often fly off the roadbed on high-speed railway lines, hitting the tracks, vehicles and facilities around the line, causing ballast splashing. This causes damage to the track and train structure, greatly increases the maintenance and repair costs of the lines and vehicles, and seriously threatens driving safety. If the splashed ballast is scattered on the rail tread, it will cause damage to the rails and wheels under the action of wheel-rail forces, accelerate track deterioration and wheel flat scars, and then cause changes in wheel-rail forces, and even cause derailment and other accidents in severe cases; if it hits the train bogie, brake cylinder, car body and other parts, it will cause damage to the train, increase unsafe factors and vehicle maintenance costs; it will cause certain harm to the facilities around the line, and may even cause personal injury; in addition, flying ballast and dust will cause environmental pollution and affect the appearance.

[0004] The uncertainty of high-speed railway ballast splash is significant. The field test method can intuitively obtain the movement law of splash ballast and the characteristics of track flow field. However, due to the many interference factors of field tests, over-reliance on existing line conditions, weak repeatability, and high research costs, there are great limitations in studying the problem of ballast splash with significant randomness. The wind tunnel test method is used to restore the flow field of the ballasted track structure, observe and test the movement behavior of ballast particles and track flow field characteristics under wind load, which can effectively overcome the above problems.

[0005] Therefore, how to design a wind tunnel test platform that can truly restore high-speed railway ballast splash is an urgent problem to be solved by technicians in this field. By restoring and analyzing the generation and development mechanism of ballast splash, scientific and effective ballast splash prevention and control suggestions are put forward, thereby ensuring the safe operation of high-speed trains and reducing the cost of line maintenance. Summary of the invention

[0006] An embodiment of the present invention provides a ballast splash wind tunnel test platform, which overcomes the shortcomings of the existing ballast splash restoration analysis, such as limited restoration accuracy of ballasted track flow field characteristics, inability to consider the influence of ballasted track structural parameters on ballast splash, and inability to finely observe the movement behavior of ballast splash and the flow field characteristics of the track structure during the occurrence and development of ballast splash.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme.

[0008] A ballast splash wind tunnel test platform, comprising: a ballast splash test bench, a test bench bracket, a high-speed train carriage bottom structure model, a sleeper model, a rail model, a ballast shoulder model, ballast aggregate and a wind speed test device;

[0009] The ballast splash test bench is connected and fixed to the high-speed train car bottom structure model and the wind tunnel laboratory floor respectively through the test bench bracket, the test bench bracket is height-adjustable, the sleeper model is placed on the surface of the ballast aggregate, the ballast aggregate is placed on the surface of the ballast splash test bench, the rail model is fixed to the top surface of the rail bearing groove of the sleeper model, the ballast shoulder model is fixed to both sides of the sleeper model and the ballast aggregate, and the wind speed testing device is fixed to the surface of the ballast aggregate between the sleeper model.

[0010] Preferably, the platform further comprises: a protective net, wherein the protective net is fixed to one end of the ballast splash test bench located at the wind tunnel outlet.

[0011] Preferably, the protective net is composed of a wire mesh fixed to the inner side of a wooden frame, the side length of each mesh is smaller than the average particle size of the ballast particles, and the length of the wooden frame is the same as the width of the ballast splash test bench.

[0012] Preferably, the platform further comprises: a video acquisition device, which is located just above the middle of the ballast splash test bench and is used to acquire and record the displacement characteristics of the ballast sample during the test.

[0013] Preferably, the test bench bracket is a double-layer angle steel structure, a series of circular holes are arranged on the surface of the angle steel, and anchor rods are used to pass through the circular holes to connect and fix the double-layer angle steel, and to adjust the height of the test bench bracket.

[0014] Preferably, the high-speed train compartment bottom structure model is made of tempered glass material.

[0015] Preferably, there are multiple sleeper models, the lateral spacing between the centers of the sleeper models is adjustable, and wind pressure measuring points are arranged on the surfaces of the sleeper models.

[0016] Preferably, the ballast shoulder model is fixed on both sides of the ballast aggregate and sleeper model, the slope of the ballast shoulder model is 1:1.75, the stacking height can be adjusted to 0cm, 5cm, 10cm or 15cm, and wind pressure measuring points are set on the surface of the ballast shoulder model.

[0017] Preferably, the material of the rail model is iron sheet, holes are punched at the bottom of the front and rear ends of the rail model, and the rail model is connected and fixed to the sleeper model using anchor rods. The shape of the rail model is completely consistent with the cross-sectional shape of the high-speed railway rail.

[0018] Preferably, the wind speed testing device is located between the two middle spans of the sleeper models, and includes: a wind speed testing device bracket, and a series of wind speed testing probes in different transverse and longitudinal positions, the probes are installed on the wind speed testing device bracket, and can simultaneously test the wind speed of the measuring points in the horizontal and vertical directions, the wind speed testing device bracket is placed inside the track bed, and the transverse and longitudinal positions of the wind speed testing device bracket are adjustable.

[0019] It can be seen from the technical solutions provided by the above embodiments of the present invention that the embodiments of the present invention provide a ballast splash wind tunnel test platform, which can accurately simulate the occurrence conditions of high-speed railway ballast splash, restore the occurrence and development characteristics of ballast splash, and monitor the ballast splash flow field data in real time, and is easy to operate. Compared with the prior art, the present invention also has the following advantages:

[0020] (1) The ballast splash wind tunnel test platform of the present invention is specially used for simulating and analyzing the ballast splash of high-speed railways. By accurately simulating the shape characteristics of the roadbed, ballast shoulder, rail sleeper, rail and carriage bottom of the ballasted track line of the high-speed railway, it can accurately restore the occurrence and development process of the ballast splash of the high-speed railway and test the flow field characteristics of the ballast splash.

[0021] (2) The present invention can simulate the occurrence and development of ballast splashing under different roadbed parameter conditions by increasing or decreasing the amount of ballast aggregate between the sleeper models, adjusting the ballast shape, material and other parameters in the ballast aggregate between the sleeper boxes, the ballast shoulder pile height of the ballast shoulder model, and the height between the car bottom model and the top surface of the ballast splashing test bench.

[0022] (3) The present invention can synchronously test the wind speed intensity and distribution characteristics at different transverse and longitudinal positions on the surface of the track bed model, as well as the wind pressure intensity and distribution characteristics in different areas on the surface of the track sleeper model and the ballast shoulder model by adjusting the wind speed testing device and the wind pressure measuring points on the surface of the sleeper model and the ballast shoulder model, so as to obtain the occurrence and development mechanism of ballast splashing.

[0023] (4) The present invention uses a video acquisition device located above the ballast splash test bench to obtain the movement behavior of ballast splash during the test in real time, thereby avoiding the threat of ballast splash to test personnel and improving the safety and accuracy of the test.

[0024] (5) The ballast splash wind tunnel test platform of the present invention has a simple structure, is easy to load and unload, is easy to operate, and has a relatively low test cost.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description, which will become obvious from the following description, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0027] Figure 1 A schematic structural diagram of a ballast splash wind tunnel test platform provided by an embodiment of the present invention;

[0028] Figure 2 A schematic front view of a ballast splash wind tunnel test platform provided by an embodiment of the present invention;

[0029] Figure 3 A schematic top view of a ballast splash wind tunnel test platform provided in an embodiment of the present invention.

[0030] Figure Number:

[0031] 1- ballast splash test bench; 2- test bench bracket; 3- high-speed train car bottom structure model; 4- sleeper model; 5- rail model; 6- ballast shoulder model; 7- wind tunnel laboratory boundary; 8- ballast aggregate; 9- wind speed test device; 10- protection net; 11- video acquisition device. DETAILED DESCRIPTION

[0032] The 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 throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0033] It will be understood by those skilled in the art that, unless expressly stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the 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 refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or coupling. The term "and / or" used herein includes any unit and all combinations of one or more associated listed items.

[0034] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0035] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each embodiment does not constitute a limitation on the embodiments of the present invention.

[0036] The embodiment of the present invention provides a ballast splash wind tunnel test platform for realistically simulating the occurrence and development process of ballast splash and the surface flow field characteristics of a ballasted track structure, such as Figure 1-3 As shown, it includes: a ballast splash test bench 1, a test bench bracket 2, a high-speed train car bottom structure model 3, a sleeper model 4, a rail model 5, a ballast shoulder model 6, a wind tunnel laboratory boundary 7, ballast aggregate 8, a wind speed test device 9, a protective net 10, and a video acquisition device 11.

[0037] The ballast splash test bench 1 is connected and fixed to the bottom structure model 3 of the high-speed train car and the floor of the wind tunnel laboratory through the test bench bracket 2. The test bench bracket 2 is a double-layer angle steel structure. A series of circular holes with an interval of 0.02m are set on the surface of the angle steel. Anchor rods are passed through the circular holes to connect and fix the double-layer angle steel and adjust the height of the test bench bracket. The height adjustable mode of the above-mentioned test bench bracket 2 can adjust the height of the test bench and eliminate the influence of the laboratory boundary layer under different incoming wind speed conditions in the wind tunnel test. At the same time, by adjusting the bracket height between the ballast splash test bench 1 and the bottom structure model 3 of the high-speed train car, the occurrence and development of ballast splash on the ballasted track surface under different car bottom height conditions and the change characteristics of the ballasted track flow field data can be simulated.

[0038] The shape and size of the high-speed train car bottom structure model 3 are the same as those of the CRH3 EMU middle car. It is made of tempered glass material. On the basis of ensuring the strength of the car bottom structure model, the model mass can be reduced, which is convenient for disassembly and operation. While reducing the test cost, it also provides a high level of safety for the test personnel. At the same time, the tempered glass is a transparent material, which can clearly observe the movement state of ballast splashing during the test.

[0039] The sleeper model 4 is placed on the surface of the ballast aggregate 8. The shape and size of the sleeper model 4 are exactly the same as those of the Type III concrete sleepers on the ballasted track of the high-speed railway, with a length of 2.6m, a bottom width of 0.32m, and a maximum height of 0.26m. A total of 4 spans of the above-mentioned sleeper models 4 are set, and the lateral spacing between the centers of each sleeper model is set to 0.6m (the spacing is adjustable). A total of 102 wind pressure measuring points are set on the surface of each span of the sleeper model 4, including 28 on the top surface and 37 on the sides, so that the synchronous testing of the flow field data in different areas of the sleeper surface can be realized.

[0040] The rail model 5 is fixed to the top surface of the rail groove of the sleeper model 4. The rail model 5 is made of iron sheet material. Holes are punched at the bottom of the front and rear ends of the rail model 5. Anchor rods are used to connect and fix the rail model 5 to the sleeper model 4. The shape of the rail model 5 is completely consistent with the cross-sectional shape of the 60kg / m rail of the high-speed railway.

[0041] The ballast shoulder model 6 is fixed on both sides of the sleeper model 4 and the ballast aggregate 8. The slope of the ballast shoulder model 6 is 1:1.75, and the stacking height can be adjusted to 0cm, 5cm, 10cm or 15cm. A total of 84 wind pressure measuring points are set on the surface of the ballast shoulder model 6, including 56 on the inner side of the track bed and 28 on the outer side.

[0042] The ballast aggregate 8 is placed on the surface of the ballast splash test bench 1. The ballast aggregate 8 is taken from the ballasted track line of the high-speed railway. The ballast aggregate 8 that meets the grading requirements of the special ballast of the high-speed railway is screened. The screened ballast is washed and dried to prevent dust from being generated during the test and affecting the test results. The treated ballast is evenly filled on the surface of the ballast splash test bench 1 and is filled and compacted in layers.

[0043] In order to further optimize the technical solution of the present invention, the number, shape, material, density and other parameters of the ballast aggregate 8 above the ballast splash wind tunnel test bench 1 can be adjusted, so as to restore the occurrence and development law of ballast splash under different roadbed quality conditions and test the flow field data of ballasted track.

[0044] The wind speed test device 9 is fixed between the middle two span rail sleeper models 4, and includes: a wind speed test device bracket, and a series of wind speed test probes in different horizontal and vertical positions. The test probes are installed on the wind speed test device bracket and are located above the roadbed. The wind speed of 8 measuring points with a spacing of 8 cm in the horizontal direction and the wind speed of 6 measuring points with a spacing of 5 cm in the vertical direction can be tested simultaneously. The wind speed test device bracket is placed inside the roadbed, and its horizontal and vertical positions can be adjusted. The test probe is connected to the electronic scanning valve through a conduit to achieve real-time acquisition of the wind speed of the flow field above the track.

[0045] In order to further optimize the technical solution of the present invention, the protective net 10 is fixed at the end of the ballast splash test bench 1 (that is, the ballast splash test bench is located at one end of the wind tunnel exit), and is composed of a wire mesh fixed to the inside of a wooden frame. The side length of each grid is smaller than the average particle size of the ballast particles (the side length of each grid in the embodiment of the present invention is 0.02m), and the length of the wooden frame is the same as the width of the ballast splash test bench 1, which can prevent the ballast particles from flying off the test bench during the test, causing the loss of samples, or even damaging the wind tunnel laboratory fan.

[0046] In order to further optimize the technical solution of the present invention, the video acquisition device 11 is located just above the middle of the ballast splash test bench 1, and can acquire and record the displacement characteristics of the ballast sample during the test in real time.

[0047] In summary, the ballast splash wind tunnel test platform provided by the present invention is dedicated to the simulation and analysis of high-speed railway ballast splash. By accurately simulating the shape characteristics of the roadbed, ballast shoulder, sleeper, rail and car bottom of the ballasted track line of the high-speed railway, it can accurately restore the occurrence and development process of high-speed railway ballast splash and test the flow field characteristics of ballast splash. By increasing or decreasing the amount of ballast aggregates between the sleeper models, adjusting the parameters such as the ballast shape and material in the ballast aggregates between the sleeper boxes, the ballast shoulder stacking height of the ballast shoulder model, and the height between the car bottom model and the top surface of the ballast splash test bench, it is possible to simulate the occurrence and development of ballast splash under different roadbed parameter conditions. Through the wind speed test device and the wind pressure measurement point, the intensity and distribution characteristics of the wind speed and wind pressure in different areas of the roadbed model, sleeper model and ballast shoulder model surface can be synchronously tested to obtain the occurrence and development mechanism of ballast splash. The video acquisition device can obtain the ballast splashing movement behavior in the test in real time, avoid the threat of ballast splashing to the test personnel, and improve the safety and accuracy of the test. At the same time, the ballast splashing wind tunnel test platform of the present invention has a simple structure, is easy to load and unload, is easy to operate, and has a relatively low test cost.

[0048] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0049] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0050] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A ballast splash wind tunnel test platform, characterized in that: include: Ballast splash test bench, test bench bracket, high-speed train carriage bottom structure model, sleeper model, rail model, ballast shoulder model, ballast aggregate and wind speed test device; The ballast splash test bench is connected and fixed to the high-speed train car bottom structure model and the wind tunnel laboratory floor respectively through the test bench bracket, the test bench bracket is height-adjustable, the sleeper model is placed on the surface of the ballast aggregate, the ballast aggregate is placed on the surface of the ballast splash test bench, the rail model is fixed to the top surface of the rail bearing groove of the sleeper model, the ballast shoulder model is fixed to both sides of the sleeper model and the ballast aggregate, and the wind speed test device is fixed to the surface of the ballast aggregate between the sleeper model; There are multiple sleeper models, the lateral spacing between the centers of the sleeper models is adjustable, and wind pressure measuring points are set on the surface of the sleeper model; The wind speed testing device is located between the two middle span sleeper models, and includes: a wind speed testing device bracket, and a series of wind speed testing probes in different transverse and longitudinal positions. The probes are installed on the wind speed testing device bracket and can simultaneously test the wind speed of the measuring points in the horizontal and vertical directions. The wind speed testing device bracket is placed inside the track bed, and the transverse and longitudinal positions of the wind speed testing device bracket are adjustable.

2. The test platform according to claim 1, characterized in that: The platform further comprises: a protective net, which is fixed to one end of the ballast splash test bench located at the wind tunnel outlet.

3. The test platform according to claim 2, characterized in that: The protective net is composed of a wire mesh fixed on the inner side of a wooden frame, the side length of each mesh is smaller than the average particle size of ballast particles, and the length of the wooden frame is the same as the width of the ballast splash test bench.

4. The test platform according to claim 1, characterized in that: The platform also includes: a video acquisition device, which is located just above the middle of the ballast splash test bench and is used to acquire and record the displacement characteristics of the ballast sample during the test.

5. The test platform according to claim 1, characterized in that: The test bench bracket is a double-layer angle steel structure, a series of circular holes are arranged on the surface of the angle steel, and anchor rods are passed through the circular holes to connect and fix the double-layer angle steel, and to adjust the height of the test bench bracket.

6. The test platform according to claim 1, characterized in that: The high-speed train carriage bottom structure model is made of tempered glass material.

7. The test platform according to claim 1, characterized in that: The ballast shoulder model is fixed on both sides of the ballast aggregate and sleeper model, the slope of the ballast shoulder model is 1:1.75, the stacking height can be adjusted to 0cm, 5cm, 10cm or 15cm, and wind pressure measuring points are set on the surface of the ballast shoulder model.

8. The test platform according to claim 1, characterized in that: The material of the rail model is iron sheet. Holes are punched at the bottom of the front and rear ends of the rail model. Anchor rods are used to connect and fix the rail model to the sleeper model. The shape of the rail model is completely consistent with the cross-sectional shape of the high-speed railway rail.

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