Railway non-buried subgrade pile plate structure underpassing highway bridge and construction method

Abstract

The application provides a railway non-buried subgrade pile plate structure underpassing a highway bridge and a construction method, wherein the method comprises the following steps: filling or digging to a bottom cushion layer preset elevation position of a bearing plate; pouring two rows of pile foundations along a railway subgrade; after the pile body concrete of the pile foundation reaches a preset strength, digging a bracket beam foundation pit; chiseling the top of the pile foundation so that the top of the pile foundation reaches a preset elevation position; pouring a bracket beam on the pile foundation; backfilling the bracket beam foundation pit and pouring the bearing plate on the bracket beam as the railway subgrade; layer-by-layer backfilling and compacting the subgrade soil on both sides of the bearing plate; and after the bracket beam and the bearing plate are constructed to reach a preset time, fixing a ballastless track structure on the bearing plate. By using the application, the problems of the existing subgrade structure, such as effective clearance being easily limited, long construction period, additional settlement deformation of an existing highway bridge pier caused by additional load of a filling subgrade, and the like, can be solved.

Description

Technical Field

[0001] This invention relates to the field of railway subgrade engineering technology, and in particular to a non-buried subgrade pile-slab structure and construction method for railways passing under highway bridges. Background Technology

[0002] In existing railway and highway intersection projects, when a railway needs to pass under a highway, buried roadbed structures, deep foundation pit support structures, or long-span bridge structures are typically used. However, buried roadbed structures and deep foundation pit support structures require large-scale excavation and backfilling, have long construction periods, and result in significant total and post-construction settlement, with differential settlement being difficult to control. This has a significant impact on the surrounding environment, especially on the existing highway bridge pile foundations, and is detrimental to the normal operation of the highway bridge. While long-span bridge structures reduce excavation, the bridge structure itself has a certain height, and the effective clearance from the railway surface to the bottom of the highway bridge is prone to exceed the limit. Furthermore, railway bridges have long construction periods, require a large amount of large machinery and equipment, and have high construction costs, increasing the complexity of design and construction, which is detrimental to the safety of highway bridges. Summary of the Invention

[0003] In view of the above problems, the purpose of this invention is to provide a non-buried roadbed pile-slab structure and construction method for railways passing under highway bridges, so as to solve the problems of existing roadbed structures having limited effective clearance, long construction period, and additional settlement and deformation caused by the additional load of the embankment on the existing highway bridge piers.

[0004] This invention provides a non-buried roadbed pile-slab structure for a railway underpass bridge, comprising: two rows of pile foundations, a support beam disposed on top of the two rows of pile foundations, a bearing plate laid on the support beam, and a ballastless track structure disposed on the bearing plate, wherein...

[0005] The two rows of pile foundations are set up correspondingly along the railway subgrade and pass under the highway bridge, wherein the pile foundations located under the highway bridge are set between the existing bridge piers;

[0006] Each support beam has its two ends set on the opposite piles of the two rows of pile foundations;

[0007] The bearing plate serves as the railway subgrade and is correspondingly installed with the two rows of pile foundations;

[0008] Each support plate is correspondingly set to the ballastless track structure.

[0009] Preferably, each row of pile foundations includes side piles located at both ends of the railway subgrade and center piles located between the side piles;

[0010] The supporting beam includes a side supporting beam installed on the side pile and a middle supporting beam installed on the middle pile.

[0011] Preferably, the support beam is rigidly connected to the pile foundation, and the main reinforcement bars of the pile foundation are embedded in the support beam.

[0012] Preferably, reinforcing ribs are provided on the corner bevels of the bearing plate, and crack-resistant steel mesh is provided at the bottom of the end of the bearing plate.

[0013] Preferably, the side support beam overlaps with the load-bearing plate, and the side support beam and the load-bearing plate are connected by sleeve pins; wherein,

[0014] A sliding layer is laid at the overlap between the side support beam and the bearing plate. The sliding layer is made of polyester filament composite polyethylene geomembrane.

[0015] The sleeve pin includes a pre-embedded steel bar set inside the side support beam and a rectangular sleeve set inside the bearing plate;

[0016] The central pile is rigidly connected to the central support beam and the bearing plate, wherein the main reinforcement of the central pile passes through the central support beam and is anchored into the bearing plate.

[0017] This invention also provides a construction method for a non-buried railway subgrade pile-slab structure for an underpass highway bridge, wherein the construction method includes:

[0018] Fill or excavate to the preset elevation of the bottom cushion layer of the bearing slab;

[0019] Two rows of pile foundations are poured along the railway subgrade, wherein the two rows of pile foundations pass under the highway bridge, and the pile foundations located under the highway bridge are poured between the highway bridge piers;

[0020] Once the concrete of the pile body reaches the preset strength, the foundation pit for the supporting beam is excavated.

[0021] The top of the pile foundation is chiseled away so that the top of the pile foundation reaches a preset elevation position;

[0022] The supporting beam is cast onto the pile foundation;

[0023] Backfill the foundation pit of the supporting beam and pour the bearing plate onto the supporting beam to serve as the railway subgrade;

[0024] The subgrade soil on both sides of the bearing plate is backfilled and compacted in layers;

[0025] Once the construction of the support beam and the bearing plate is completed and a preset time has elapsed, the ballastless track structure is fixed to the bearing plate.

[0026] Preferably, before the step of filling or excavating to the preset elevation position of the bottom cushion layer of the bearing slab, the method further includes: treating the ground occupied by the pile foundation and setting up temporary drainage works.

[0027] Preferably, the pouring of two rows of pile foundations along the railway subgrade includes: positioning each pile foundation and installing a protective casing;

[0028] Drill holes in the casing and place the reinforcing cage into the casing;

[0029] Concrete is poured into the casing to complete the pouring of the pile foundation.

[0030] Preferably, the step of casting the support beam onto the pile foundation includes:

[0031] The bottom cushion layer of the support beam is poured onto the foundation pile;

[0032] The reinforcing bars are tied to the bottom pad of the beam, the structural pins are overlapped, and the formwork is erected.

[0033] Concrete is poured into the template to form the support beam.

[0034] Preferably, casting the bearing plate onto the support beam includes:

[0035] The bearing plate cushion layer is poured onto the supporting beam;

[0036] The reinforcing bars are tied to the bearing plate cushion layer, and the reinforcing bars and sleeves connected to the ballastless track structure are pre-embedded, and the formwork is erected;

[0037] Concrete is poured into the template to form the load-bearing plate.

[0038] As can be seen from the above technical solution, the railway non-buried roadbed pile-slab structure and construction method for underpass highway bridges provided by the present invention bears the load of the track and train and transfers it to the pile foundation through the support beam, and then to the ground. Its structure is simple and the stress is clear, which can effectively improve the stability and bearing capacity of the railway roadbed, reduce the construction difficulty, shorten the construction period, and have little impact on the surrounding environment. It has good environmental protection benefits and is suitable for railway engineering construction under complex terrain conditions such as limited effective clearance of underpass highway bridges.

[0039] To achieve the foregoing and related objectives, one or more aspects of the invention include the features that will be described in detail below. The following description and accompanying drawings illustrate certain exemplary aspects of the invention. However, these aspects indicate only a few of the various ways in which the principles of the invention can be used. Furthermore, the invention is intended to encompass all such aspects and their equivalents. Attached Figure Description

[0040] Other objects and results of the invention will become more apparent and readily understood with reference to the following description taken in conjunction with the accompanying drawings. In the drawings:

[0041] Figure 1 This is a schematic diagram of the plan layout of the pile-slab structure according to an embodiment of the present invention;

[0042] Figure 2 This is a longitudinal elevation view of a pile-slab structure according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic cross-sectional view of a pile-slab structure according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the rigid connection between the side pile and the side support beam according to an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the rigid connection between the central pile, the central support beam, and the bearing plate according to an embodiment of the present invention;

[0046] Figure 6 This is a structural diagram of the overlap between the side support beam and the bearing plate according to an embodiment of the present invention;

[0047] Figure 7 This is a schematic diagram of the construction process of a railway non-buried roadbed pile-slab structure for an underpass bridge according to an embodiment of the present invention.

[0048] The reference numerals in the figures include:

[0049] 1. Side pile, 2. Middle pile, 3. Side support beam, 4. Middle support beam, 5. Bearing plate, 51. First bearing plate, 52. Second bearing plate, 6. Existing bridge pier, 7. Existing bridge pier pile foundation, 8. New railway track, 9. Existing bridge boundary line, 10. Pile foundation, 11. Support beam, 13. Ballastless track structure, 14. Sliding layer, 15. Rectangular sleeve, 16. Embedded steel reinforcement.

[0050] In all the accompanying drawings, the same reference numerals indicate similar or corresponding features or functions. Detailed Implementation

[0051] In the following description, numerous specific details are set forth for illustrative purposes and to provide a thorough understanding of one or more embodiments. However, it will be apparent that these embodiments may also be implemented without these specific details. In other instances, well-known structures and devices are shown in block diagram form for ease of description of one or more embodiments.

[0052] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0053] In response to the aforementioned problems such as the limited effective clearance of existing roadbed structures, long construction periods, and the additional settlement and deformation caused by the additional load on existing highway bridge piers due to embankment roadbeds, this invention provides a non-buried railway roadbed pile-slab structure and construction method for passing under highway bridges.

[0054] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0055] To illustrate the structure of the railway non-buried roadbed pile-slab structure for underpass highway bridges provided by this invention. Figures 1 to 6 Exemplary illustrations of railway non-buried roadbed pile-slab structures for underpass highway bridges are provided from different perspectives. Specifically, Figure 1 The planar arrangement of the pile-slab structure according to an embodiment of the present invention is shown; Figure 2 The longitudinal elevation of the pile-slab structure according to an embodiment of the present invention is shown; Figure 3 A transverse cross-section of a pile-slab structure according to an embodiment of the present invention is shown; Figure 4 A rigid connection between the side pile and the side support beam according to an embodiment of the present invention is shown; Figure 5 This illustrates the rigid connection between the central pile, the central support beam, and the bearing plate according to an embodiment of the present invention; Figure 6 The overlapping structure of the side support beam and the load-bearing plate according to an embodiment of the present invention is shown.

[0056] like Figures 1 to 6 As shown in the figure, the railway non-buried roadbed pile-slab structure for underpassing a highway bridge provided by the present invention includes: two rows of pile foundations 10, a support beam 11 set on top of the two rows of pile foundations 10, a bearing plate 5 laid on the support beam 11, and a ballastless track structure 13 set on the bearing plate 5. The two rows of pile foundations 10 are arranged correspondingly along the railway roadbed and pass under the highway bridge. The pile foundations 10 located under the highway bridge are arranged between existing bridge piers 6. The two ends of each support beam 11 are set on the opposite pile foundations 10 of the two rows of pile foundations. The bearing plate 5 serves as the railway roadbed and is arranged correspondingly to the two rows of pile foundations 10. Each bearing plate 5 is arranged correspondingly to the ballastless track structure 13.

[0057] The railway non-buried roadbed pile-slab structure of the present invention is designed for situations where, due to effective clearance constraints, a low embankment roadbed is required to pass under an existing highway bridge. In order to reduce the additional load on the existing highway bridge piers caused by the embankment roadbed and prevent the highway bridge piers from experiencing additional settlement and deformation due to the additional load, this structure can achieve railway passing under highway without large-scale excavation. At the same time, it has good load-bearing capacity, structural stability and low construction and maintenance costs, ensuring the normal operation of highways and railways.

[0058] Among them, the pile-slab structure is used to support the newly built railway track 8, and the bearing plate 5 is directly connected to the ballastless track structure 13. The pile foundation 10, the supporting beam 11, the bearing plate 5 are rigidly connected and together with the roadbed soil and rock form a bearing structure system with strong integrity and good stability.

[0059] Among them, pile foundation 10 is a reinforced concrete bored pile. Low-headroom drilling equipment can be used for pile formation, or manual excavation can be used when the groundwater is deep. Two rows of pile foundations 10 are set longitudinally along the railway subgrade under and on both sides of the existing highway bridge, and laterally between the existing bridge piers 6. Existing bridge pier pile foundations 7 are set under the existing bridge piers 6 to support the existing bridge piers 6. The pile foundations 10 located under the highway bridge are set between the existing bridge piers 6, that is, the pile foundations 10 located under the highway bridge do not exceed the boundary line 9 of the existing bridge.

[0060] Each row of pile foundations 10 includes side piles 1 at both ends of the railway subgrade and central piles 2 between the side piles 1. The processing and hoisting of the reinforcing cages for each pile foundation are carried out with careful consideration of the clearance height under the bridge and the length of the cast-in-place piles, and the sections are hoisted and connected at the borehole opening. To prevent disturbance to the highway bridge, the existing piers 6 can be physically isolated and protected, such as by using attached steel or rubber anti-collision posts.

[0061] The supporting beam 11 is a cast-in-place reinforced concrete supporting beam, rigidly connected to the pile foundation 10, with the main reinforcement bars of the pile foundation 10 embedded in the supporting beam 11. The supporting beam 11 includes a side supporting beam 3 mounted on the side pile 1 and a central supporting beam 4 mounted on the central pile 2. Figure 3 and Figure 4 In the embodiment shown, a cast-in-place concrete support beam is provided at the top of each row of pile foundations 10 in the transverse direction. The top of the pile foundation 10 is embedded in the support beam 11 by about 0.1m. The main reinforcement of the pile body extends into the support beam 11, and the top of the pile is rigidly connected to the support beam 11. The support beam 11 has a stirrup reinforcement zone within the main reinforcement of the pile body and within a range of one pile diameter on both sides.

[0062] Among them, the bearing plate 5 is a cast-in-place reinforced concrete slab, which is laid on the support beam 11 as the foundation of the railway track. The first bearing plate 51 is set along one row of foundation piles 10, and the second bearing plate 52 is set along another row of foundation piles 10. Reinforcing bars are set on the corners and sides of each bearing plate 5, and crack-resistant steel mesh is set at the bottom of the end of each bearing plate 5.

[0063] exist Figure 5 and Figure 6 In the illustrated embodiment, the side support beam 3 overlaps with the bearing plate 5; a sliding layer 14 is laid at the overlap of the side support beam 3 and the bearing plate 5, and the sliding layer 14 is made of polyester filament composite polyethylene geomembrane. The side support beam 3 and the bearing plate 5 are connected by sleeve pins, and the sleeve pins include pre-embedded steel bars 16 set inside the side support beam 3 and rectangular sleeves 15 set inside the bearing plate 5. To accommodate the longitudinal expansion and contraction deformation of the bearing plate 5, the long side of the rectangular sleeve 15 is set longitudinally along the line to ensure that the rectangular sleeve 15 can move along the line. The central pile 2 is rigidly connected to the central support beam 4 and the bearing plate 5, wherein the main reinforcement of the central pile 2 passes through the central support beam 4 and is anchored into the bearing plate 5.

[0064] In addition, the bearing plate 5 is connected to the ballastless track structure 13 by pre-embedded steel bars and reinforcing sleeves. Each bearing plate 5 corresponds to one ballastless track structure 13. A reinforcing sleeve is provided inside the ballastless track structure, and pre-embedded steel bars are provided inside each bearing plate. The bearing plate and the ballastless track structure are connected to the reinforcing sleeve by the pre-embedded steel bars.

[0065] Corresponding to the above structure, the present invention also provides a construction method for a non-buried roadbed pile-slab structure for a railway underpass bridge. Figure 7 The present invention illustrates a construction process for a railway non-buried roadbed pile-slab structure for an underpass highway bridge according to an embodiment of the present invention.

[0066] like Figure 7 As shown, the present invention also provides a construction method for a non-buried railway subgrade pile-slab structure for an underpass highway bridge, wherein the construction method includes:

[0067] S1: The pre-set elevation position of the bottom cushion layer of the bearing slab during filling or excavation;

[0068] S2: Two rows of pile foundations are poured along the railway subgrade, wherein the two rows of pile foundations pass under the highway bridge, and the pile foundations located under the highway bridge are poured between the highway bridge piers;

[0069] S3: After the concrete of the pile body of the pile foundation reaches the preset strength, excavate the foundation pit for the supporting beam;

[0070] S4: Chisel away the top of the pile foundation so that the top of the pile foundation reaches a preset elevation position;

[0071] S5: Cast the support beam onto the pile foundation;

[0072] S6: Backfill the foundation pit of the supporting beam and pour the bearing plate onto the supporting beam as the railway subgrade;

[0073] S7: Backfill and compact the subgrade soil on both sides of the bearing plate in layers;

[0074] S8: After the construction of the support beam and the bearing plate is completed and the preset time is reached, the ballastless track structure is fixed on the bearing plate.

[0075] Prior to the step of filling or excavating to the preset elevation position of the bottom cushion layer of the bearing slab, the method further includes: treating the ground occupied by the pile foundation and setting up temporary drainage works.

[0076] In step S2, the pouring of two rows of pile foundations along the railway subgrade includes: positioning each pile foundation and embedding a casing; drilling holes in the casing and placing a reinforcing cage into the casing; and pouring concrete into the casing to complete the pouring of the pile foundation.

[0077] In step S5, the casting of the support beam onto the pile foundation includes: casting the bottom cushion layer of the support beam onto the foundation pile; tying the reinforcing bars to the bottom cushion layer of the support beam, lapping the structural pins, and erecting the formwork; and pouring concrete into the formwork to form the support beam.

[0078] In step S6, the process of casting the bearing plate onto the support beam includes: casting the bearing plate cushion layer onto the support beam; tying the reinforcing bars to the bearing plate cushion layer and pre-embedding the reinforcing bars and sleeves connected to the ballastless track structure, and erecting a template; and pouring concrete into the template to form the bearing plate.

[0079] In a specific embodiment of the present invention, the first step is to treat the ground surface before pile foundation construction, set up temporary drainage works, and prepare the site. The second step is to fill or excavate to the design elevation of the bottom layer of the bearing slab, accurately locate each pile, install casings, drill and inspect holes, lower the reinforcing cage, and pour concrete. The third step is to excavate the supporting beam foundation pit after the pile concrete reaches the design strength and passes the test, and chisel away the pile heads to the design elevation of the pile top. The fourth step is to pour the bottom layer of the supporting beam after the pile quality test is passed, tie the reinforcing bars, install the lap joint construction pins, erect the formwork, and pour the supporting beam concrete. The fifth step is to backfill the supporting beam foundation pit, pour the bearing slab layer, tie the reinforcing bars, pre-embed the reinforcing bars and connecting sleeves for connection with the track, erect the formwork, and pour the bearing slab concrete. The sixth step is to backfill and compact the subgrade soil on both sides of the bearing slab in layers. The seventh step is to construct the top ballastless track structure 28 days after the completion of the supporting beam and bearing slab construction, after passing the non-destructive testing method.

[0080] The specific structure of the apparatus in the method of the present invention is as described in the foregoing embodiments. Since the method adopts all the technical solutions of all the foregoing embodiments, it has at least all the beneficial effects brought about by the technical solutions of the foregoing embodiments, which will not be described in detail here.

[0081] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the description and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A non-buried pile-slab structure for railway subgrade passing under a highway bridge, characterized in that, include: Two rows of pile foundations, a support beam positioned on top of the two rows of pile foundations, a load-bearing plate laid on the support beam, and a ballastless track structure mounted on the load-bearing plate, wherein, The two rows of pile foundations are set up correspondingly along the railway subgrade and pass under the highway bridge, wherein the pile foundations located under the highway bridge are set between the existing bridge piers; Each support beam has its two ends set on the opposite piles of the two rows of pile foundations; The bearing plate serves as the railway subgrade and is correspondingly installed with the two rows of pile foundations; Each support plate is correspondingly provided with the ballastless track structure; Each row of pile foundations includes side piles located at both ends of the railway subgrade and center piles located between the side piles; The supporting beam includes a side supporting beam disposed on the side pile and a middle supporting beam disposed on the middle pile; The side support beam overlaps with the bearing plate, and the side support beam and the bearing plate are connected by a sleeve pin; wherein... A sliding layer is laid at the overlap between the side support beam and the bearing plate. The sliding layer is made of polyester filament composite polyethylene geomembrane. The sleeve pin includes a pre-embedded steel bar set inside the side support beam and a rectangular sleeve set inside the bearing plate; The central pile is rigidly connected to the central support beam and the bearing plate, wherein the main reinforcement of the central pile passes through the central support beam and is anchored into the bearing plate.

2. The railway non-buried roadbed pile-slab structure for underpass bridges according to claim 1, characterized in that, The support beam is rigidly connected to the pile foundation, and the main reinforcement bars of the pile foundation are embedded in the support beam.

3. The railway non-buried roadbed pile-slab structure for underpass highway bridges according to claim 2, characterized in that, Reinforcing ribs are provided on the beveled edges of the bearing plate, and crack-resistant steel mesh is provided at the bottom of the end of the bearing plate.

4. A construction method for a non-buried pile-slab structure of railway subgrade for a highway underpass, characterized in that, The construction method for the railway non-buried roadbed pile-slab structure of the underpass bridge according to any one of claims 1 to 3 includes: Fill or excavate to the preset elevation of the bottom cushion layer of the bearing slab; Two rows of pile foundations were poured along the railway subgrade, with the two rows of pile foundations passing under a highway bridge, and the pile foundations located under the highway bridge were poured between existing bridge piers; Once the concrete of the pile body reaches the preset strength, the foundation pit for the supporting beam is excavated. The top of the pile foundation is chiseled away so that the top of the pile foundation reaches a preset elevation position; The supporting beam is cast onto the pile foundation; Backfill the foundation pit of the supporting beam and pour the bearing plate onto the supporting beam to serve as the railway subgrade; The subgrade soil on both sides of the bearing plate is backfilled and compacted in layers; Once the construction of the support beam and the bearing plate is completed and a preset time has elapsed, the ballastless track structure is fixed to the bearing plate.

5. The construction method for the non-buried roadbed pile-slab structure of the railway underpass bridge according to claim 4, characterized in that, Before the step of filling or excavating to the preset elevation position of the bottom cushion layer of the bearing slab, the method further includes: treating the ground occupied by the pile foundation and setting up temporary drainage works.

6. The construction method for the non-buried roadbed pile-slab structure of the railway underpass bridge according to claim 4, characterized in that, The construction of two rows of pile foundations along the railway subgrade includes: positioning each pile foundation and installing a protective casing; Drill holes in the casing and place the reinforcing cage into the casing; Concrete is poured into the casing to complete the pouring of the pile foundation.

7. The construction method for the non-buried roadbed pile-slab structure of the railway underpass bridge according to claim 4, characterized in that, The process of casting the support beam onto the pile foundation includes: The bottom cushion layer of the support beam is poured onto the pile foundation; The reinforcing bars are tied to the bottom pad of the beam, the structural pins are overlapped, and the formwork is erected. Concrete is poured into the template to form the support beam.

8. The construction method for the non-buried roadbed pile-slab structure of the railway underpass bridge according to claim 4, characterized in that, The process of casting the bearing plate onto the support beam includes: The bearing plate cushion layer is poured onto the supporting beam; The reinforcing bars are tied to the bearing plate cushion layer, and the reinforcing bars and sleeves connected to the ballastless track structure are pre-embedded, and the formwork is erected; Concrete is poured into the template to form the load-bearing plate.

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