Large-displacement track expansion device for low-medium speed maglev bridge

Abstract

The low-speed maglev large-span bridge end super-large displacement track row expansion device is used to realize high-precision maglev track and foundation structure deformation coordination control, and well solves the expansion deformation of the bridge end super-large displacement caused by temperature difference. The track row structure unit is continuously arranged from the main span side pier to the boundary pier on the top surface of the bridge body, the longitudinal front end of the first track row structure unit is anchored and connected with the main span beam body through the anchoring device, and the last track row structure unit longitudinally spans the super-large beam joint. The main body of the track row structure unit includes the bearing rail beam segment and the frame type track row unit, the bearing rail beam segment is integrated with the main span beam body, the frame type track row unit is installed on the bearing rail beam segment through the elastic strip fastener, and the bearing rail beam segment and the frame type track row unit are provided with longitudinal expansion structure and vertical and horizontal limiting structure. A pair of F-shaped guide rails are fixedly installed on the top surface of the frame type track row unit in transverse direction, and the wing plate joint is arranged between the longitudinally adjacent F-shaped guide rails.

Description

Technical Field

[0001] This invention relates to the field of medium- and low-speed maglev rail transit, specifically to a large-displacement track extension device at the beam end of a medium- and low-speed maglev long-span bridge. Background Technology

[0002] In recent years, long-span bridge structures have frequently appeared in the field of medium- and low-speed maglev transportation, which brings a series of problems such as the interaction between "train-track-bridge". In particular, the longitudinal expansion and contraction deformation of the bridge under temperature load can reach 200mm or more within the design temperature range, which cannot be met by conventional medium- and low-speed maglev transportation jointed track panels (including Type I, Type II and Type III expansion joints).

[0003] Existing high-speed railways, urban rail transit, intercity railways and other wheel-rail transportation also have large displacement expansion joints, which are generally called rail expansion joints. These expansion joints are only applicable to wheel-rail systems and are not applicable to medium and low speed maglev transportation.

[0004] The invention patent application CN109024107A discloses a large displacement telescopic device for medium- and low-speed maglev track beams, which is installed across the gaps in the track beams of medium- and low-speed maglev rail transit. At the top of each of the two beam ends of adjacent track beams, an end rail panel structure and a support for the telescopic device are provided. A simply supported small longitudinal beam is installed between the supports, with one end rotatable and the other end rotatable and slidable. A modular telescopic rail panel is slidably mounted on the upper end of the simply supported small longitudinal beam via a longitudinal beam sliding device. The modular telescopic rail panel includes several rail panel sub-units. The track beams and end rail panel structures of each rail panel sub-unit are equipped with lateral movement devices. Linkage devices are provided between adjacent rail panel sub-units and between the sub-units and the end rail panel structures, with both ends of the linkage devices connected to the lateral movement devices. In other words, by using linkage devices (especially X-shaped linkages) and lateral sliding devices, the large longitudinal displacement of the track beam is automatically and equally distributed across the gap changes between each rail panel sub-unit, thus adapting to the structural requirements of slotted tracks in medium- and low-speed maglev transit. However, this device greatly weakens the stability of the track structure, especially the multiple hinged supports and multi-degree-of-freedom simply supported longitudinal beams, which can easily cause vehicle-track resonance. At the same time, the X-shaped connection causes frequent changes in the sleeper spacing within the device, which can easily cause malfunctions in the train's suspension control system.

[0005] The large expansion and contraction deformation and complex displacement at the beam ends of long-span bridges in medium- and low-speed maglev systems present a significant challenge: maintaining high-precision coordinated control of deformation between the maglev track and the foundation structure, as well as ensuring high reliability over the long term. This is one of the key difficulties in the field of medium- and low-speed maglev transportation.

[0006] Existing conventional electromagnetic levitation low-speed maglev tracks primarily employ a multi-layered, combined sleeper-type track structure, with rail panels as the integral laying unit. Longitudinally, adjacent rail panels are connected via various types of rail panel joints. Vertically, the rail panels are connected to the track beam by pre-installed reinforcing bars and a secondary cast-in-place monolithic track bed to ensure a strong connection. Therefore, limited by the structural form and its constraints, the track system's vertical and lateral adjustment capabilities are limited to fasteners, with a maximum of approximately 20mm. Longitudinal adjustment is achieved solely through the construction of rail gaps at the rail panel joints; the currently mature Type III joint has an expansion range of approximately 80mm. Due to the stringent requirements of vehicle suspension control regarding rail gap limits and their arrangement along the line, solutions such as widening the rail gaps at the beam ends or increasing the number of joints are not feasible.

[0007] In summary, based on the existing research and application of maglev engineering structures at home and abroad, the design of the track structure on a long-span maglev bridge is a problem that cannot be solved by existing technical solutions at home and abroad. It belongs to the "no man's land" where there is no successful experience to refer to worldwide, and it is a "bottleneck" technology for maglev transportation systems under the application conditions of long-distance trunk lines. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a large displacement track extension device at the beam end of a medium- and low-speed maglev long-span bridge, so as to effectively overcome the technical difficulties in the design of track structure on a long-span maglev bridge, realize high-precision coordinated control of deformation between maglev track and foundation structure, and solve the problem of large displacement expansion and contraction deformation at the beam end of the bridge and track caused by temperature difference, so as to meet the structural requirements of medium- and low-speed maglev transportation for jointed tracks.

[0009] The technical solution adopted by this invention to solve its technical problem is as follows:

[0010] The present invention relates to a large-displacement track panel expansion device for a medium-low speed maglev long-span bridge beam, characterized in that: it includes track panel structural units continuously arranged on the top surface of the bridge beam from the main span side piers towards the junction piers, wherein the longitudinal front end of the first track panel structural unit is anchored to the main span beam via an anchoring device, and the last track panel structural unit longitudinally spans the large beam gap between the end faces of the main span beam and the side span beam; the main body of the track panel structural unit includes a rail-bearing beam segment and a frame-type track panel unit, the rail-bearing beam segment is fixedly integrated with the main span beam, and the frame-type track panel unit is fastened and installed on the rail-bearing beam segment by elastic fasteners, and there is a longitudinal expansion structure and a vertical and lateral limiting structure between the rail-bearing beam segment and the frame-type track panel unit; a pair of F-type guide rails are fixedly installed laterally at intervals on the top surface of the frame-type track panel unit, and a wing plate joint is provided between longitudinally adjacent F-type guide rails;

[0011] The main body of the rail-bearing beam segment has a portal-shaped cross-section, with a top plate and two side webs connected as a single unit. The side webs are fixedly integrated with the main span beam. Final SectionThe webs on both sides of the rail-bearing beam segment overlap the super-large beam joint on the top surface of the side span beam; on the top surface of the top plate, rail-bearing platforms that protrude upwards are set at intervals along the track direction on both sides in the transverse direction, and T-shaped longitudinal beam blocks that protrude upwards and extend longitudinally are set in the middle part of the top plate.

[0012] The frame-type rail panel unit includes a pair of longitudinal rail sleepers spaced laterally and several transverse rail sleepers spaced equally longitudinally. Each transverse rail sleeper is welded and fixed to the top surface of the longitudinal rail sleeper. The F-type guide rail is installed and fixed to the top surface of the transverse rail sleeper by bolt assembly. The elastic fastener is installed on the top of each rail support platform to form a clamping force on the longitudinal rail sleeper on the same side.

[0013] The longitudinal telescopic structure and the vertical and lateral limiting structure include a guide plate, a side friction plate, and a bottom friction plate; the side friction plate is fixedly installed on the side walls of the two wing plates on the top of the T-shaped longitudinal beam block, and the bottom friction plate is fixedly installed on the bottom surface of the wing plate; the guide plate is set corresponding to the T-shaped longitudinal beam block, and is composed of a side plate and a bottom plate to form an L-shaped structure. The upper end of the side plate is welded to the transverse rail sleeper, and the side plate and the side friction plate on the same side, and the bottom plate and the bottom friction plate on the same side form a friction pair.

[0014] The beneficial effects of this invention are mainly reflected in the following aspects:

[0015] It consists of a fixed-end track panel structural unit and several expansion-zone track panel structural units connected longitudinally. The expansion range is determined by the number of track panel structural units, and the number of track panel structural units can be adjusted according to the expansion range, exhibiting high flexibility and adaptability to large expansion ranges. Specifically, the fixed-end track panel structural unit is anchored to the main beam at the corresponding position of the fixed support on the main span side pier, while the expansion-zone track panel structural units are arranged longitudinally towards the movable end of the super-large beam joint, realizing coordinated deformation of the track structure and the bridge structure.

[0016] In the frame-type track panel unit, the longitudinal sleepers can freely expand and contract along the longitudinal direction via elastic clips. The two are adjusted steplessly along the longitudinal direction by the clamping of the clips. Furthermore, the elastic clips have a simple structure, are easy to replace, and are convenient to maintain.

[0017] The guide plate welded to the bottom of the frame-type track panel unit contacts and rubs against the friction plates on both sides of the T-shaped longitudinal beam block to achieve lateral limitation of the unit-type track panel structure; the guide plate contacts and rubs against the friction plates on both sides of the bottom of the T-shaped longitudinal beam block to achieve vertical limitation of the unit-type track panel structure; the interaction between the two ensures that the unit-type track panel structure can only slide longitudinally, and the unit-type track panel has high smoothness and reliability under temperature load.

[0018] The frame-type track panel unit is welded from simple H-section steel sleepers, resulting in a simple and reliable structure with well-defined mechanical properties. Furthermore, the frame-type track panel structure exhibits good overall integrity and high bending stiffness, ensuring stability of the track panel structure under extremely large displacements of the bridge structure.

[0019] This invention addresses the design of track structures for long-span maglev bridges. Considering the application characteristics of long-distance trunk line structures and the technical requirements of maglev systems, it adopts the principles of "rail panel steel rail + beam-rail separation design + arthropod motion biomimetic design". Combined with the specific structural dimensions of this invention, it can achieve a super-large displacement of 500mm at the beam end, effectively solving the problem of expansion and contraction deformation of bridges and tracks caused by temperature differences. Attached Figure Description

[0020] This instruction manual includes the following thirteen figures:

[0021] Figure 1 This is a schematic diagram of the arrangement of the ultra-large displacement track panel expansion device at the beam end of the low-speed maglev long-span bridge in this invention on a long-span bridge.

[0022] Figure 2 This is a perspective view of the ultra-large displacement track extension device at the beam end of a low-speed maglev long-span bridge in this invention.

[0023] Figure 3 This is a three-dimensional view of the telescopic zone unit-type track panel in the telescopic device for the ultra-large displacement track panel at the beam end of a low-speed maglev long-span bridge in this invention.

[0024] Figure 4 This is a cross-sectional view of the unit-type track panel structure in the telescopic zone of the telescopic device for the ultra-large displacement track panel at the beam end of a low-speed maglev long-span bridge in this invention.

[0025] Figure 5 This is a three-dimensional view of the frame-type rail panel in the ultra-large displacement rail panel expansion device at the beam end of the low-speed maglev long-span bridge of the present invention.

[0026] Figure 6 This is a cross-sectional view of the frame-type rail panel in the ultra-large displacement rail panel expansion device at the beam end of the low-speed maglev long-span bridge of the present invention.

[0027] Figure 7 This is a perspective view of the guide plate in the telescopic device for the ultra-large displacement track panel at the beam end of a low-speed maglev long-span bridge in this invention.

[0028] Figure 8 This is a perspective view of the elastic fastener in the ultra-large displacement track panel expansion device at the beam end of a low-speed maglev long-span bridge in this invention.

[0029] Figure 9 This is a cross-sectional view of the elastic fastener in the ultra-large displacement rail extension device at the beam end of the low-speed maglev long-span bridge in this invention.

[0030] Figure 10 This is a three-dimensional view of the foundation structure under the rail panel in the ultra-large displacement rail panel expansion device at the beam end of the low-speed maglev long-span bridge of the present invention.

[0031] Figure 11 This is a cross-sectional view of the foundation structure under the rail panel in the ultra-large displacement rail panel expansion device at the beam end of the low-speed maglev long-span bridge of this invention.

[0032] Figure 12 This is a top view of the fixed-end unit-type track panel structure in the low-speed maglev long-span bridge beam end ultra-large displacement track panel expansion device of the present invention.

[0033] Figure 13 This is a cross-sectional view of the fixed-end unit-type track panel structure in the ultra-large displacement track panel expansion device at the beam end of the low-speed maglev long-span bridge of the present invention.

[0034] The diagram shows the component names and their corresponding markings: rail support beam segment 10, first rail support beam segment 10a. Final Section Rail support beam segment 10b; rail support platform 20, elastic fastener 21, fixing bolt assembly 211, iron pad 212, T-bolt 213, elastic clip 214, track gauge block 215, rail under pad 216.

[0035] T-shaped longitudinal beam block 30, anchoring device 31, side friction plate 32, bottom friction plate 33, H-shaped anchor pile 311, connecting rod 312, high-strength nut 313; frame-type rail panel unit 40, F-shaped guide rail 41, wing plate joint 411, keyway 412, side plate 441, bottom plate 442, transverse steel sleeper 43, guide plate 44, longitudinal steel sleeper 45; main span beam body A, side span beam body B, extra-large beam joint C, junction pier D, main span side pier E. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] Reference Figure 1 The present invention relates to a medium-low speed maglev long-span bridge beam end ultra-large displacement track panel expansion device, comprising track panel structural units continuously arranged on the top surface of the bridge beam from the main span side pier E to the junction pier D. The longitudinal front end of the first track panel structural unit is anchored to the main span beam A via an anchoring device 31, meaning the first track panel structural unit is a fixed-end track panel structural unit, and the rest are expansion zone track panel structural units. The last track panel structural unit longitudinally spans the ultra-large beam joint C between the end faces of the main span beam A and the side span beam B. (Refer to...) Figures 2 to 4The main body of the track panel structure unit includes a rail-bearing beam segment 10 and a frame-type track panel unit 40. The rail-bearing beam segment 10 is fixedly integrated with the main span beam A. The frame-type track panel unit 40 is fastened onto the rail-bearing beam segment 10 by elastic fasteners 21. The rail-bearing beam segment 10 and the frame-type track panel unit 40 have a longitudinal telescopic structure and vertical and lateral limiting structures. A pair of F-type guide rails 41 are fixedly installed laterally at intervals on the top surface of the frame-type track panel unit 40, and a wing plate joint 411 is provided between longitudinally adjacent F-type guide rails 41.

[0038] Reference Figure 3 and Figure 4 The main body of the rail-bearing beam segment 10 has a portal-shaped cross-section, with a top plate and two side webs connected as one piece. The two side webs are fixedly integrated with the main span beam A. (Refer to...) Figure 1 ,in Final Section The webs of the track-bearing beam segment 10b on both sides overlap the super-large beam joint C on the top surface of the side span beam B. (Refer to...) Figure 4 On the top surface of the top plate, there are upwardly protruding rail support platforms 20 arranged at intervals along the track direction on both sides in the transverse direction, and T-shaped longitudinal beam blocks 30 that are upwardly protruding and extend longitudinally are arranged in the middle part of the top plate.

[0039] The T-shaped longitudinal beam block 30 can be a single block set at intervals along the track direction, or it can be a structure that is the same length as the track support beam segment 10.

[0040] Reference Figure 5 and Figure 6 The frame-type track panel unit 40 includes a pair of longitudinal rail sleepers 45 spaced laterally and several transverse rail sleepers 43 spaced equidistantly longitudinally. Each transverse rail sleeper 43 is welded and fixed to the top surface of the longitudinal rail sleepers 45. The F-type guide rail 41 is installed and fixed to the top surface of the transverse rail sleepers 43 by bolt assembly. The elastic clip fastener 21 is installed on the top of each rail support platform 20 to form a clamping force on the longitudinal rail sleepers 45 on the same side. The two ends of the F-type guide rail are respectively provided with wing plate joints 411 and keyways 412. The transverse rail sleepers 43 and longitudinal rail sleepers 45 are all made of H-section steel and should comply with the provisions of "Hot-rolled H-beams and Split T-beams" (GB / T 11263).

[0041] Reference Figures 4 to 7The longitudinal telescopic structure and the vertical and lateral limiting structure include a guide plate 44, a side friction plate 32, and a bottom friction plate 33. The side friction plate 32 is fixedly mounted on the side walls of the top two wing plates of the T-shaped longitudinal beam block 30, and the bottom friction plate 33 is fixedly mounted on the bottom surface of the wing plates. The guide plate 44 is positioned corresponding to the T-shaped longitudinal beam block 30 and consists of a side plate 441 and a bottom plate 442 forming an L-shaped structure. The upper end of the side plate 441 is welded to the transverse rail sleeper 43, and both ends of the side plate 441 are bent outwards to achieve longitudinal guidance. The side plate 441 and the side friction plate 32, and the bottom plate 442 and the bottom friction plate 33 on the same side form friction pairs, achieving longitudinal telescopicity and lateral and vertical limiting.

[0042] Reference Figure 1 , Figure 12 and Figure 13 The anchoring device 31 is installed at the corresponding position of the fixed support of the main span side pier E, and includes anchor piles 311 and connecting rods 312. There are four anchor piles 311 arranged at intervals in the longitudinal and transverse directions. Each anchor pile 311 passes downward through the top plate of the first rail bearing beam segment 10a and is anchored into the main span beam body A to a certain depth. The connecting rods 312 pass laterally through the anchor piles 311 and the waist of the longitudinal rail sleepers 45 on both sides, and are locked and fixed by high-strength nuts 313.

[0043] Reference Figure 2 The longitudinally arranged rail sleepers 45 are fastened to the rail support platform 2 on both sides. (Refer to...) Figure 8 and Figure 9 The elastic clip fastener 21, from bottom to top, consists of a fixing bolt assembly 211, a steel pad 212, a T-bolt 213, an elastic clip 214, a rail underplate 216, and a gauge block 215. The fixing bolt assembly 211 is positioned at the corner of the steel pad 212 and stably connects it to the rail support platform 20. The T-bolts 213 are inverted and inserted into the grooves on both sides of the steel pad 212, pressing the elastic clip 214 against the gauge block 215. The gauge block 215 provides stable clamping to the bottom plate of the longitudinal sleeper 45. The rail underplate 216 is made of a material with high rigidity, moderate friction coefficient, and aging resistance, preferably high-performance polyurethane.

[0044] Reference Figure 1 and Figure 2The illustrated embodiment of the ultra-large displacement track panel expansion device for a medium-low speed maglev long-span bridge beam is composed of several expansion zone unit-type track panel structural units and one fixed-end track panel structural unit connected longitudinally. The fixed-end track panel structural unit is located at the corresponding position of the fixed support of the main span side pier (E) and is anchored to the main span beam A through anchoring device 31. The expansion zone unit-type track panel structural units are located at the side span of the long-span bridge and are arranged longitudinally towards the movable end of the ultra-large beam joint C. Wing plate joints 411 (a common type I expansion joint with a maximum expansion amount of 20mm) are provided between the F-type guide rails 41 of each track panel structural unit. Under the action of temperature load, the frame-type track panel unit 40 slides longitudinally along the guide plate 44. The guide plate 44 simultaneously limits the lateral and vertical movement of the frame-type track panel unit 40, ensuring that each frame-type track panel unit 40 can only slide within a certain range longitudinally. The overall structure resembles an arthropod, and the length of the entire device is determined according to the amount of expansion it can accommodate. For example, if the expansion joint requirement of a long-span bridge is 200mm, then 10 identical frame-type track panel units 40 need to be connected in series.

[0045] This invention addresses the design of track structures for long-span maglev bridges. Considering the application characteristics of long-distance trunk line structures and the technical requirements of maglev systems, it adopts the principles of "rail panel steel rail + beam-rail separation design + arthropod motion biomimetic design." Combined with the specific structural dimensions of this invention, it can achieve ultra-large displacement of beam end expansion and contraction at the level of 500mm, effectively overcoming the technical difficulties in track structure design for long-span maglev bridges and achieving high-precision coordinated control of deformation between the maglev track and the foundation structure.

[0046] The above description is merely an illustration of some principles of the low-speed maglev long-span bridge beam end ultra-large displacement track extension device of the present invention, and is not intended to limit the present invention to the specific structure and applicable scope shown and described. Therefore, all possible modifications and equivalents are within the scope of the patent application of the present invention.

Claims

1. An expansion joint device for ultra-large displacement track panels at the beam ends of medium- and low-speed maglev long-span bridges, characterized in that: The structure includes a continuous track panel unit on the top surface of the bridge beam, extending from the main span side pier (E) towards the junction pier (D). The longitudinal front end of the first track panel unit is anchored to the main span beam (A) via an anchoring device (31), and the last track panel unit longitudinally spans the large beam joint (C) between the end faces of the main span beam (A) and the side span beam (B). The main body of the track panel unit includes a rail-bearing beam segment (10) and a frame-type track panel unit (40). 10) The frame-type rail panel unit (40) is fixedly integrated with the main span beam (A). The frame-type rail panel unit (40) is fastened and installed on the rail-bearing beam segment (10) by elastic fasteners (21). The rail-bearing beam segment (10) and the frame-type rail panel unit (40) have a longitudinal expansion structure and a vertical and lateral limiting structure. A pair of F-type guide rails (41) are fixedly installed laterally on the top surface of the frame-type rail panel unit (40). A wing plate joint (411) is set between the longitudinally adjacent F-type guide rails (41). The main body of the rail-bearing beam segment (10) has a portal-shaped cross-section, with a top plate and two side webs connected as one piece. The two side webs are fixedly integrated with the main span beam (A). Final Section The webs of the rail-bearing beam segment (10b) on both sides cross the super-large beam joint (C) and overlap on the top surface of the side span beam body (B); on the top surface of the top plate, rail-bearing platforms (20) that are raised upward are provided at intervals along the track direction on both sides in the transverse direction, and T-shaped longitudinal beam blocks (30) that are raised upward and extended longitudinally are provided in the middle part of the top plate. The frame-type rail panel unit (40) includes a pair of longitudinal steel sleepers (45) arranged laterally and a number of transverse steel sleepers (43) arranged longitudinally at equal intervals. Each transverse steel sleeper (43) is welded and fixed to the top surface of the longitudinal steel sleeper (45). The F-type guide rail (41) is installed and fixed to the top surface of the transverse steel sleeper (43) by bolt assembly. The elastic fastener (21) is installed on the top of each rail support platform (20) to form a clamping force on the longitudinal steel sleeper (45) on the same side. The longitudinal telescopic structure and the vertical and lateral limiting structure include a guide plate (44), a side friction plate (32), and a bottom friction plate (33). The side friction plate (32) is fixedly installed on the side walls of the two wing plates on the top of the T-shaped longitudinal beam block (30), and the bottom friction plate (33) is fixedly installed on the bottom surface of the wing plate. The guide plate (44) is set corresponding to the T-shaped longitudinal beam block (30) and is composed of a side plate (441) and a bottom plate (442) forming an L-shaped structure. The upper end of the side plate (441) is welded to the transverse rail sleeper (43), and the side plate (441) and the side friction plate (32) and the bottom plate (442) and the bottom friction plate (33) on the same side form a friction pair.

2. The telescopic track panel expansion device for ultra-large displacement at the beam end of a medium-low speed maglev long-span bridge as described in claim 1, characterized in that: The T-shaped longitudinal beam block (30) is arranged in a single block form at intervals along the track direction, or it adopts a structural form that is the same length as the rail beam segment (10) and is continuous.

3. The telescopic track panel expansion device for ultra-large displacement at the beam end of a medium-low speed maglev long-span bridge as described in claim 1, characterized in that: The anchoring device (31) is set at the corresponding position of the fixed support of the main span side pier (E), including anchor piles (311) and connecting rods (312); there are 4 anchor piles (311) arranged longitudinally and laterally, and each anchor pile (311) passes downward through the top plate of the first section of the rail bearing beam (10a) and is anchored into the main span beam (A) to a certain depth; the connecting rod (312) passes laterally through the anchor piles (311) and the waist of the longitudinal rail sleepers (45) on both sides, and is locked and fixed by high-strength nuts (313).

4. The telescopic track panel expansion joint for large displacement at the beam end of a medium-low speed maglev long-span bridge as described in claim 1, characterized in that: The elastic clip fastener (21) consists of a fixing bolt assembly (211), an iron pad (212), a T-bolt (213), an elastic clip (214), a rail pad (216), and a gauge block (215) from bottom to top. The fixing bolt assembly (211) is arranged at the corner of the iron pad (212) and stably connected to the rail support platform (20). The T-bolt (213) is upside down in the grooves on both sides of the iron pad (212) to press the elastic clip (214) onto the gauge block (215), and the gauge block (215) forms a stable clamping on the bottom plate of the longitudinal steel sleeper (45).

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