Design method for spatial curved beam of high-speed maglev

Abstract

The present invention discloses a design method for a high-speed maglev spatial curve beam, which includes: obtaining and determining the layout parameters of the spatial curve beam, including the beam span length, the minimum plane radius, the minimum vertical radius, and the minimum combined radius; obtaining the sectional boundary parameters of the spatial curve beam, including the boundary parameters of the beam top plate and the web; and designing the structural surface of the spatial curve beam according to the layout parameters and sectional boundary parameters of the spatial curve beam. With the layout parameters and sectional boundary parameters of the spatial curve beam as inputs, the structural surface of the spatial curve beam is designed through the above parameters, and different structural surface designs are adopted for different radius positions of the line. The beam is separated from the long-span bridge, and by reducing the length of the beam and lowering the beam height, it is convenient to adjust the beam line type; and in the large curve section, the design method of using folds instead of curves is adopted, reducing the required mold specifications and facilitating the millimeter-level adjustment requirements during the installation of the track beam, so that the spatial curve beam can meet the accuracy requirements of high-speed maglev track operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of maglev track, and particularly relates to a design method for a high-speed maglev spatial curve beam. Background Art

[0002] Maglev technology generates lift and thrust through magnets, enabling the vehicle to levitate very close to the "guide rail". Since there is no frictional force of physical contact, most of the power is used to overcome air resistance. In terms of operating energy consumption, high-speed maglev has obvious advantages compared with high-speed railway.

[0003] The maglev train track beam is the basis for the operation of high-speed maglev trains, and the track beam is a high-precision component in the maglev track structure system. In high-speed maglev technology, since the levitation height and guiding gap of high-speed maglev trains are only 8 - 10 mm, the accuracy requirements for the construction quality and installation quality of the track are extremely high.

[0004] The high-speed maglev track train reaches a speed of 600 km / h. In the section of small-radius curve line, it poses great difficulties and challenges to the structural design of the track beam. The structural design of conventional highway and railway curve beams mainly considers the load-bearing capacity and designs the beam based on the load-bearing capacity. However, the design accuracy requirements of high-speed maglev track beams are high, and the structural design is mainly affected by deformation and design errors in small-radius curve sections. Therefore, the existing conventional design methods are difficult to be applied to the design of high-speed maglev track beams. Summary of the Invention

[0005] The purpose of the present invention is to provide a design method for a high-speed maglev spatial curve beam to solve the problems that the accuracy and error requirements of high-speed maglev beams are high, and the existing design methods are difficult to meet the design requirements.

[0006] The present invention is achieved through the following technical solutions:

[0007] A design method for a high-speed maglev spatial curve beam, comprising:

[0008] Obtaining and determining the layout parameters of the spatial curve beam, including the beam span length, minimum planar radius, minimum vertical radius, and minimum composite radius;

[0009] Obtaining the sectional boundary parameters of the spatial curve beam, including the boundary parameters of the beam top plate and web;

[0010] Designing the structural surface of the spatial curve beam according to the layout parameters and sectional boundary parameters of the spatial curve beam.

[0011] In some embodiments, designing the structural surface of the spatial curve beam includes:

[0012] Determine the superelevation angle, cross-slope torsion rate, and the spatial alignment of the beam top plate and the track structure surface according to the line parameters; the line parameters include line plane parameters, vertical alignment parameters, and the maximum designed passing speed.

[0013] When the radius of the beam top plate is no more than 1200 m, the curve is made curved to keep it consistent with the line; when the radius is greater than 1200 m, the structural surface is designed in the way of replacing the curve with folds.

[0014] In some embodiments, the design of the structural surface in the way of replacing the curve with folds includes designing the lengths of the structural surfaces under different plane radii and different vertical radii, and the structural surfaces include the stator structural surface, the sliding structural surface, and the guiding structural surface.

[0015] In some embodiments, the spatial curve beam structural surface is designed in the way of replacing the curve with folds in multiples of the standard stator unit length.

[0016] In some embodiments, the superelevation is not considered when designing the structural surface in the way of replacing the curve with folds.

[0017] In some embodiments, the design at the superelevation position is achieved by changing the inclination angle of the bottom surface of the beam support.

[0018] In some embodiments, when designing the structural surface in the way of replacing the curve with folds, the length of the structural surface is designed based on multiples of the length of the standard stator unit.

[0019] In some embodiments, the spatial curve beam structure is checked and tested, and the high-speed maglev spatial curve beam is designed and optimized according to the results of the check and test.

[0020] In some embodiments, the check and test of the spatial curve beam structure include the check and test of the bearing capacity, deformation, and dynamic characteristics.

[0021] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0022] The present invention takes the layout parameters and beam section boundary parameters of the spatial curve beam as inputs, designs the structural surface of the spatial curve beam through the above parameters, adopts different structural surface designs for different radius positions of the line, separates the beam from the long-span bridge, and by reducing the length of the beam and lowering the beam height, it is convenient to adjust the beam alignment; and in the large curve section, the design method of replacing the curve with folds is adopted, reducing the required mold specifications and facilitating the millimeter-level adjustment requirements during the installation of the track beam, so that the spatial curve beam can meet the accuracy requirements of the high-speed maglev track operation. Description of the Drawings

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 Schematic diagram of the beam cross-section structure with supports having different inclination angles at ultra-high positions in the embodiments of the present invention.

[0025] Figure 2 Schematic diagram of the structural surface of the spatial curved beam in the embodiments of the present invention.

[0026] Figure 3 Schematic diagram of the spatial curved beam structure in the embodiments of the present invention.

[0027] Figure 4 Schematic diagram of the cross-section of the beam body of the spatial curved beam in the embodiments of the present invention.

[0028] Wherein:

[0029] 10. Spatial curved beam, 101. Beam body, 102. Support, 103. Maglev functional component;

[0030] 11. Stator structural surface, 12. Sliding structural surface, 13. Guiding structural surface. Specific embodiments

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention.

[0032] In the design of high-speed maglev spatial curved beams, for the design requirements of small-radius curve parts, it is necessary to achieve plane alignments such as R = 650m / V = 100km / h, concave curve alignments such as R = 750m / V = 100km / h, and convex curve alignments such as R = 800m / V = 100km / h, etc., which bring great difficulties to the design of spatial curved beams. It is necessary to study the method of replacing the curve with a fold for the track structural surface and the curve beam.

[0033] In some embodiments of the present invention, the design method of high-speed maglev spatial curved beams includes:

[0034] Obtain and determine the layout parameters of the spatial curved beam, including beam span length, minimum plane radius, minimum vertical radius, and minimum combined radius;

[0035] Obtain the sectional boundary parameters of the spatial curved beam, including the boundary parameters of the beam top plate and the web;

[0036] Design the structural surface of the spatial curved beam according to the layout parameters of the spatial curved beam and the sectional boundary parameters of the beam.

[0037] Among them, designing the structural surface of the spatial curved beam includes:

[0038] Determine the superelevation angle, cross slope twist rate and the spatial linearity of the beam top plate and the track structural surface according to the line parameters; the line parameters include the line plane parameters, vertical linearity parameters, and maximum designed passing speed;

[0039] When R ≤ 1200m, the beam top plate adopts the method of curved production for curves to keep it consistent with the line, and when it is greater than 1200m, the structural surface is designed by the method of replacing curves with folds.

[0040] Designing the structural surface by the method of replacing curves with folds includes designing the lengths of the structural surfaces under different plane radii and different vertical radii. As Figure 2 shown, the structural surface includes the stator structural surface 11, the sliding structural surface 12, and the guiding structural surface 13. Due to the machining, installation and other errors of each functional part of the spatial curved beam, the design error that can be replaced by folds is usually a part within the total allowable error range; in the design of the lengths of the stator structural surface, the sliding structural surface, and the guiding structural surface, through the calculation and analysis of the errors of the track beam structure, the range of replacing curves with folds of the structural surface is shown in Table 1.

[0041] Table 1

[0042]

[0043] Steps for the design of the prestressed steel bundle layout; including:

[0044] Determine the number of prestressed bundles arranged through the calculation of the conventional curved beam (the control parameter is to meet the vertical deflection requirement under the live load);

[0045] Set the bridge camber through the calculation of the conventional curved beam, including the vertical camber to resist the self-weight and the secondary load, and the transverse camber to resist the radial force of the prestressed steel bundle.

[0046] Steps for the design of the ordinary reinforcement layout; including:

[0047] The layout of the ordinary reinforcement is mainly determined by the construction requirements of the railway code to meet the crack and torsion resistance requirements of each key part.

[0048] Steps for the design of the bearing layout; including:

[0049] Based on the bridge calculation results, obtain the load distribution at the support points and select a suitable finished bearing.

[0050] The design of the super-elevation position is achieved by changing the cross-sectional shape of the beam at the support. By changing the inclination angle of the bottom surface of the beam support, the design of the super-elevation position is realized, as Figure 1 shown in the schematic diagram of the spatial curved beam structure with supports of different inclination angles at the super-elevation position. According to the actual requirements of the spatial curved beam, its cross slope angle is usually set to be 0° to 12°. Referring to Figure 1 shown, from the right side to the left side, the inclination angle of the support of the spatial curved beam changes from 0° to 12°.

[0051] The lengths of the structural surfaces of the spatial curved beams are all designed by replacing the curve with folds based on the standard stator units of the multiple module numbers. The length of the standard stator unit is 1.032 m, which can reduce the production of non-standard parts, lower the construction difficulty and cost, and thus meet the linear requirements of the high-speed maglev specification.

[0052] Adopting the design method in the above-mentioned embodiment, the beam span length is taken as the standard length of 12.384 m, the minimum plane radius value is 650 m, the minimum vertical curve radius value is 750 m, and the minimum combined radius value is 530 m.

[0053] To be connected smoothly with the straight-section beam, where there is no super-elevation, the beam height should be the same as that of the straight beam, which is 1.7 m.

[0054] The super-elevation is adjusted by the change of the beam cross-section at the support.

[0055] The standard span of the spatial curved beam is selected as 12.384 m, so that the track beam and the long-span bridge are separated. After the length of the track beam becomes shorter, not only the beam height can be reduced, but also it is extremely beneficial for the linear adjustment. Especially in the large-curve section, the curve can be replaced by folds, reducing the specifications and models of the molds. The weight of the beam body is small, which greatly facilitates the millimeter-level adjustment requirements for the installation of the track beam, thus meeting the high-precision requirements of a speed of 600 km / h.

[0056] Referring to Figure 3 and Figure 4 , the beam body 101 of the spatial curved beam 10 adopts a π-shaped cross-sectional structure. Supports 102 are respectively arranged at both ends of the beam body 101. The beam body 101 and the supports 102 can be integrally cast and processed with concrete. The bottom surface of the beam body 101 is suspended and located above the bottom surface of the supports 102. In this way, when the inclination angle of the support is set to be 0° to 12°, the spatial curved beam can have a cross slope angle of 0° to 12° during installation through the support.

[0057] To facilitate the processing and forming of the spatial curved beam with supports of different inclination angles, the outer side surface of the support 102 can be set as an arc surface, as Figure 4 shown.

[0058] For the design of the spatial curve beam, the spatial position of the maglev functional component 103 on the beam surface is set conformally according to the line type of the spatial curve beam and the cross slope angle it has.

[0059] Specifically, for a spatial curve beam with a span of 12.384 m, the maglev functional components are divided into 4 sections for setting. In this way, by adjusting the spatial positions of the 4 sections of maglev functional components respectively, flexible adjustment can be made according to the design position requirements of the maglev functional components on the spatial curve beam, and different spatial curve beams can be matched by fitting the spatial positions of the 4 sections of maglev functional components.

[0060] Check and calculate the structure of the spatial curve beam and conduct tests. Design and optimize the high-speed maglev spatial curve beam according to the results of the check and calculation and tests. The check and calculation and tests of the spatial curve beam structure include the check and calculation and tests of the bearing capacity, deformation, and dynamic characteristics.

[0061] Conduct a static load test on the spatial curve beam, simulate the stress state during the operation stage of the beam body, and conduct a check and calculation of the bearing capacity and deformation of the spatial curve beam.

[0062] The steps for the check and calculation design of the spatial curve beam structure include:

[0063] 1) Bearing capacity check and calculation;

[0064] Conduct a bearing capacity check and calculation of the structure and a cross-section stress check and calculation according to different load combination conditions.

[0065] 2) Deformation check and calculation;

[0066] Load for the Z-direction deformation check and calculation: Load according to the beam span length, and the maximum vertical deflection when Pz = 32.8 kN / m.

[0067] Load for the Y-direction deformation check and calculation: Load according to the beam span length, and the maximum lateral deflection when Py = 5.0 kN / m.

[0068] Deformations in the Z and Y directions caused by temperature difference: Calculate according to the temperature difference value determined by the environmental climate conditions. Use a multi-physics field finite element simulation software to establish a finite element model of the concrete simply supported beam, simulate and analyze the temperature field of the test beam on a typical sunny day in spring, compare the measured temperatures of the top plate, web, bottom plate, and corbel parts of the beam with the simulated temperature time history law respectively, verify the accuracy of the thermodynamic boundary adjustment, and conduct a check and calculation of the temperature difference deformation of the spatial curve beam. For the test beam, compare the vertical temperature difference mode, top plate lateral temperature difference mode, and web lateral temperature difference mode respectively, and obtain the temperature mode suitable for the temperature difference deformation test of the test beam for check and calculation and tests.

[0069] Check and calculation of the control of concrete shrinkage and creep deformation.

[0070] 3) Dynamic characteristic check and calculation;

[0071] The calculation is carried out according to the requirements of the "Design Standard for High-Speed Maglev Transportation" (CJJ / T 310-2021).

[0072] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0073] In addition, when the terms "horizontal" and "vertical" appear in the description of the present invention, it does not mean that the components are required to be absolutely horizontal or hanging vertically, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0074] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, if the terms "set", "installed", "connected", "connected" are used, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0075] The above is only a preferred embodiment of the present invention, and does not impose any formal limitations on the present invention. Any simple modifications and equivalent changes made to the above embodiments based on the technical essence of the present invention all fall within the protection scope of the present invention.

Claims

1. Design method for high-speed maglev spatial curved girder, characterized in that Including: Obtain and determine the layout parameters of the spatial curved beam, including beam span length, minimum plane radius, minimum vertical radius, and minimum combined radius; Obtain the sectional boundary parameters of the spatial curved beam, including the boundary parameters of the beam top plate and web; Design the structural surface of the spatial curved beam according to the layout parameters and sectional boundary parameters of the spatial curved beam; Design the structural surface of the spatial curved beam, including: Determine the superelevation angle, cross slope torsion rate, and the spatial linearity of the beam top plate and track structural surface according to the line parameters; the line parameters include line plane parameters, vertical linearity parameters, and maximum designed passing speed; When the radius is not greater than 1200m, the beam top plate adopts the method of curved making for curves to keep it consistent with the line, and when the radius is greater than 1200m, the structural surface is designed by replacing the curve with a fold; Designing the structural surface by replacing the curve with a fold includes designing the lengths of the structural surfaces under different plane radii and different vertical radii, and the structural surfaces include stator structural surface, sliding structural surface, and guiding structural surface; Steps for the design of the prestressed steel bundle layout; including: determining the number of prestressed layout bundles through the calculation of the conventional curved beam; setting the bridge camber through the calculation of the conventional curved beam, including the vertical camber to resist self-weight and secondary load, and the transverse camber to resist the radial force of the prestressed steel bundle; Steps for the design of the ordinary reinforcement layout; including: the layout of the ordinary reinforcement is mainly determined by the construction requirements of the railway code to meet the crack resistance and torsion resistance requirements of each key part; Steps for the design of the bearing layout; including: based on the bridge calculation results, obtaining the load distribution of the fulcrum position and selecting a suitable finished bearing; The design at the superelevation position is achieved by changing the bottom inclination angle of the beam bearing. The spatial curved beam is set with a cross slope angle of 0° to 12°. Correspondingly, the inclination angle of the bearing of the spatial curved beam is 0° to 12°. Bearings are respectively arranged at both ends of the beam body. The beam body and the bearing are integrally cast and processed with concrete. The bottom surface of the beam body is suspended and located above the bottom surface of the bearing; when the bearing is set with an inclination angle of 0° to 12°, the spatial curved beam can have a cross slope angle of 0° to 12° when installed through the bearing, and the outer side surface of the bearing is set as an arc surface; For the spatial curved beam with a span of 12.384m, the maglev functional components are divided into 4 sections for setting, and the spatial positions of the 4 sections of maglev functional components are fitted to match different spatial curved beams.

2. The design method of the high-speed maglev spatial curve beam according to claim 1, characterized in that The structural surface of the spatial curved beam is designed by replacing the curve with a fold in multiples of the standard stator unit length.

3. The design method of the high-speed maglev spatial curved beam according to claim 1, characterized in that When designing the structural surface by replacing the curve with a fold, the superelevation is not considered.

4. The design method of the high-speed maglev spatial curve beam according to claim 1, characterized in that Check and test the structure of the spatial curved beam, and design and optimize the high-speed maglev spatial curved beam according to the results of the check and test.

5. The design method of the high-speed maglev spatial curve beam according to claim 4, characterized in that The check and test of the structure of the spatial curved beam include the check and test of bearing capacity, deformation, and dynamic characteristics.

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