Segmental assembly type bridge

Abstract

The utility model belongs to the technical field of bridge engineering, and particularly relates to a segment assembly type bridge. The segmental assembly type bridge structurally comprises a segmental beam top plate, a segmental beam web plate, a segmental beam bottom plate, a convex block, a groove, a prestressed duct and a prestressed steel bar, and further comprises a necking groove formed in the end face of the segmental beam web plate and a three-section shear key unit which is arranged on the necking groove in a clamped mode and used for transversely connecting the two segmental beams. And the lining steel plate unit is arranged on the necking groove and is used for clamping the three-section type shear key unit. The sectional type bridge joint structure has the beneficial effects that the sectional type shear key units are matched with the necking grooves at least, sufficient vertical bearing capacity and certain transverse tensile capacity can be provided at the joints of the sectional beams, the connecting strength of the joints is remarkably improved, and then the structural stability degree of the whole sectional type bridge is improved.

Description

Technical Field

[0001] This application belongs to the field of bridge engineering technology, and in particular relates to a segmental assembled bridge. Background Technology

[0002] Segmental assembly bridges represent a relatively advanced modern bridge construction technology. The main components of this technology are: prefabrication of segmental beams in a factory, transportation of the segmental beams to the bridge construction site, and assembly of several segmental beams on-site. Correspondingly, the advantages of this segmental assembly technology are: no noise or dust during on-site construction, and short construction time.

[0003] Generally, the above assembly operations mainly include the following three steps: installing shear keys, filling adhesive, and tensioning prestressed steel bars. Therefore, the structural components of segmental assembled bridges generally include shear keys and prestressed steel bars. Among these, the methods for tensioning prestressed steel bars are relatively mature and straightforward, so the design and installation of shear keys are one of the key steps in the above assembly operations.

[0004] On the other hand, if the segmental beams show a significant decrease in connection strength at the assembly point, it will lead to the following problems in sequence: misalignment at the assembly joints, tilting of the segmental beams, crushing of the top plate of the segmental beams, and fatigue failure of the entire bridge.

[0005] For example, Chinese invention patent application CN115595888A, with publication date of January 13, 2023, discloses a prestressed assembly construction method for precast segmental beams of high-speed railway cable-stayed bridges. The structural components of this segmental bridge mainly include: concrete segmental beams, shear keys, corrugated metal pipes, embedded ducts, embedded steel pipes, prestressed high-strength threaded steel bars, connectors, tension end nuts, tension end washers, positioning steel bars, supporting steel bars, and U-shaped rings.

[0006] The segmental bridge in this patent application has the following advantages: it fully combines the respective advantages of prestressed high-strength threaded steel bars and prestressed steel strand bundles, which can appropriately improve the overall stability of the segmental bridge.

[0007] However, in actual use, this segmental bridge still has a certain degree of relatively poor stability of segmental beam connections. The main reason for this is that its shear key structure is a common thin plate style, which makes it difficult to provide high strength load-bearing capacity for a long time, ultimately leading to harmful misalignment at the joints. Utility Model Content

[0008] This application provides a segmental assembled bridge, the technical problem to be solved is: how to make the segmental assembled bridge have greater connection strength and load-bearing capacity at the joints, and ensure that misalignment is unlikely to occur at the joints.

[0009] The technical solution adopted by this application to solve the above problems is: a segmental assembled bridge, the structure of which includes a segmental beam top plate, a segmental beam web plate, a segmental beam bottom plate, protrusions, grooves, prestressed ducts, and prestressed steel bars, and also includes a constriction groove disposed on the end face of the segmental beam web plate, a three-segment shear key unit that is engaged on the constriction groove and used for transversely connecting two segmental beams, and an inner lining steel plate unit disposed on the constriction groove and used for engaging the three-segment shear key unit.

[0010] A further preferred technical solution is that, on a section parallel to the web of the segmental beam, the cross-sectional shape of the constriction groove includes a circular region or an isosceles trapezoidal region.

[0011] A further preferred technical solution is that the three-segment shear key unit includes two transverse tensile blocks respectively disposed on two corresponding constriction grooves of two adjacent segment beams, and a central connecting plate disposed on the two transverse tensile blocks.

[0012] A further preferred technical solution is that the three-segment shear key unit also includes a rounded corner disposed between the transverse tensile block and the central connecting plate, which is used to alleviate the stress concentration on the shear key.

[0013] A further preferred technical solution is that the thickness of the central connecting plate is ≥2.0cm.

[0014] A further preferred technical solution is that the inner lining steel plate unit includes an inner lining piece disposed in the constriction groove and used to engage the transverse tensile block, and a connecting piece disposed on two adjacent inner lining pieces and attached to the end face of the web of the segmental beam.

[0015] A further preferred technical solution is that the inner lining steel plate unit further includes a positioning hole disposed on the connecting piece and used to pass through the prestressed steel bar.

[0016] A further preferred technical solution is that the inner lining steel plate unit further includes an inner lining steel plate insertion endpoint indicator piece disposed on the inner lining piece at the end position and used to receive the blocking effect of the protrusion on the top plate or bottom plate of the segmental beam.

[0017] A further preferred technical solution is that the positioning hole is provided on the endpoint indicator piece for inserting the inner lining steel plate.

[0018] A further preferred technical solution is that: 4-8 constriction grooves are provided on the web of a single segmental beam at uniform intervals.

[0019] The beneficial effects of this application include at least the following three points.

[0020] The first and third shear key units, combined with the constriction groove, can provide sufficient vertical bearing capacity and a certain amount of lateral tensile capacity at the joints of the segmental beams, thereby significantly improving the connection strength at the joints and thus enhancing the structural stability of the entire segmental bridge.

[0021] Secondly, the inner steel plate unit, as an intermediate and transitional structure between the three-section shear key unit and the constriction groove, can disperse the pressure of the three-section shear key unit on the constriction groove, which helps to prevent the concrete structure at the constriction groove from cracking.

[0022] Third, the three-section shear key unit and the inner steel plate unit have the advantages of relatively simple and precise installation and operation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of this application.

[0024] Figure 2 This is a schematic diagram showing the location of the groove and prestressed steel bars in this application.

[0025] Figure 3 This is a schematic diagram showing the location of the inner lining steel plate unit in this application.

[0026] Figure 4 This is a schematic diagram of one structure of the three-segment shear key unit in this application.

[0027] Figure 5 For the above Figure 4 The diagram shows the outline shape of a three-segment shear key unit.

[0028] Figure 6 This is a structural schematic diagram of the inner steel plate unit in this application.

[0029] Figure 7 This is another structural schematic diagram of the three-segment shear key unit in this application.

[0030] Figure 8 This is a schematic diagram showing the insertion and installation direction of the inner steel plate unit in this application.

[0031] The meanings of the markings in the diagram are as follows.

[0032] a) the circumcircle of the center connecting plate outline; b) the insertion installation direction; c) one of the segment positions of the shear key; d) another of the segment positions of the shear key.

[0033] 11. Top plate of segmental beam, 12. Web plate of segmental beam, 13. Bottom plate of segmental beam, 14. Protrusion, 15. Groove, 16. Prestressed duct, 17. Prestressed steel bar;

[0034] 1. Narrow groove; 2. Three-section shear key unit; 3. Inner steel plate unit;

[0035] Horizontal tensile block 201, centering connecting plate 202, rounded corner 203;

[0036] Inner liner 301, connecting piece 302, positioning hole 303, and end point indicator piece for inserting inner liner steel plate 304. Detailed Implementation

[0037] The following description is merely a preferred embodiment of this application and is not intended to limit the scope of this application.

[0038] like Figures 1-8 As shown, a segmental assembled bridge structure includes a segmental beam top plate 11, a segmental beam web plate 12, a segmental beam bottom plate 13, protrusions 14, grooves 15, prestressed ducts 16, and prestressed steel bars 17. The bridge is characterized by further including a constriction groove 1 disposed on the end face of the segmental beam web plate 12, a three-segment shear key unit 2 engaged on the constriction groove 1 and used for transverse connection of two segmental beams, and an inner lining steel plate unit 3 disposed on the constriction groove 1 and used for engaging the three-segment shear key unit 2.

[0039] In this embodiment, the segmental assembled bridge, or segmental bridge for short, mainly consists of segmental beams, three-segment shear key units 2, inner steel plate units 3, and adhesives.

[0040] The aforementioned segmental beam mainly comprises a top plate 11, a web 12, a bottom plate 13, a protrusion 14, a groove 15, prestressing ducts 16, and a constriction groove 1. This segmental beam is prefabricated in a factory, with the protrusion 14 at one end and the groove 15 at the other end. Its length direction corresponds to the longitudinal direction of the segmental bridge, and the prestressing duct 16 extends through its length direction.

[0041] In addition, the protrusions 14 and grooves 15 are provided on the top plate 11 and bottom plate 13 of the segmental beam, and the prestressed ducts 16 are provided on the top plate 11, web plate 12 and bottom plate 13 of the segmental beam.

[0042] The aforementioned adhesive is a commercially available product, such as epoxy resin adhesive or polyurethane adhesive, which is used in the two gaps between the constriction groove 1 and the inner steel plate unit 3, and between the inner steel plate unit 3 and the three-section shear key unit 2.

[0043] On the other hand, the opening direction of the constriction groove 1 is perpendicular to the web 12 of the segmental beam and passes through the web 12. Both the three-segment shear key unit 2 and the inner lining steel plate unit 3 are made of high-strength steel. One inner lining steel plate unit 3 is used to engage and install all the three-segment shear key units 2 on one side of the web 12 of a single segmental beam. Therefore, when assembling two adjacent segmental beams, four inner lining steel plate units 3 are required at the joint.

[0044] Finally, the three-segment shear key unit 2 can provide sufficient vertical bearing capacity and additional lateral tensile strength, which is the first step in ensuring the connection strength at the joint of the segmental beam.

[0045] The second step in ensuring the aforementioned connection strength is as follows: the inner steel plate unit 3 is used to cover the concrete structure at the constriction groove 1, becoming an intermediate transition structure for the constriction groove 1 to engage with the three-section shear key unit 2. The inner steel plate unit 3 can both reduce the pressure generated by the three-section shear key unit 2 at the constriction groove 1 and further prevent the concrete structure at the constriction groove 1 from being directly crushed or cracked by the three-section shear key unit 2.

[0046] Ultimately, misalignment is less likely to occur at the joints of the segmental beams, the segmental beams are less likely to tilt and fall, and the top plates 11 of two adjacent segmental beams are less likely to be crushed.

[0047] On a section parallel to the web 12 of the segmental beam, the cross-sectional shape of the constriction groove 1 includes a circular region or an isosceles trapezoidal region.

[0048] In this embodiment, the first cross-sectional shape of the constriction groove 1 has an outline of three sequentially tangent arc-shaped edges, with the aforementioned circular area corresponding to the central and innermost arc-shaped edge.

[0049] The second cross-sectional shape of the constriction groove 1 is either a complete isosceles trapezoid or the aforementioned isosceles trapezoid plus a rectangle at the opening.

[0050] The "upper base" of the isosceles trapezoid is either the opening position facing the constriction groove 1. Therefore, the constriction groove 1 of the above two shapes has the dimensional characteristic of being "wider inside and narrower outside", so it can be laterally engaged with the three-section shear key unit 2.

[0051] Correspondingly, the shape of the three-section shear key unit 2 is adapted to the constriction groove 1, and its size is slightly smaller than the constriction groove 1, so that the inner steel plate unit 3 can be installed smoothly at the gap between the two.

[0052] The three-segment shear key unit 2 includes two transverse tensile blocks 201 respectively disposed on two corresponding constriction grooves 1 of two adjacent segment beams, and a central connecting plate 202 disposed on the two transverse tensile blocks 201.

[0053] In this embodiment, when the shape of the constriction groove 1 corresponds to the aforementioned circular region, the cross-sectional shape of the transverse tensile block 201 is circular, and the cross-sectional shape of the central connecting plate 202 is a "quasi-rectangular" shape with all four sides being concave arc-shaped. For details, please refer to the attached diagram. Figure 5 The four concave arc edges mentioned above represent one of the segment positions c of the two shear keys and a portion of the circumcircle a of the outlines of the two centrally located connecting plates.

[0054] When the shape of the constriction groove 1 corresponds to the aforementioned isosceles trapezoidal region, the transverse tensile block 201 is an isosceles trapezoidal block, and the central connecting plate 202 is a cuboid, corresponding to the second segment position d of the aforementioned shear key. For details, please refer to the appendix. Figure 7 .

[0055] The three-segment shear key unit 2 also includes a fillet 203 disposed between the transverse tensile block 201 and the central connecting plate 202, which is used to alleviate the stress concentration on the shear key.

[0056] In this embodiment, the rounded corner 203 is only provided between the isosceles trapezoidal block-shaped transverse tensile block 201 and the cuboid-shaped central connecting plate 202.

[0057] The rounded corner 203 and the three-segment shear key unit 2, which originally includes four tangent arc surfaces, both have a streamlined shape, which can effectively reduce stress concentration, improve the load-bearing capacity of the three-segment shear key unit 2, and benefit the connection strength at the joint.

[0058] The thickness of the centering connecting plate 202 is ≥2.0cm.

[0059] In this embodiment, when the central connecting plate 202 includes two arc-shaped surfaces, the central position of the arc-shaped surface corresponds to the position with the minimum thickness, while when the central connecting plate 202 is cuboid, its thickness is equal everywhere.

[0060] The minimum thickness and uniform thickness of the central connecting plate 202 are both ≥2.0cm. Therefore, compared with the commonly used thin plate shear keys, the three-segment shear key unit 2 has the advantage of relatively large thickness, ensuring that it can provide relatively large load-bearing capacity.

[0061] The inner lining steel plate unit 3 includes an inner lining piece 301 disposed in the constriction groove 1 and used to engage the transverse tensile block 201, and a connecting piece 302 disposed on two adjacent inner lining pieces 301 and attached to the end face of the web plate 12 of the segmental beam.

[0062] In this embodiment, the three-segment shear key unit 2 and the inner lining steel plate unit 3 are both integrally molded. The shape and size of the inner lining piece 301 are adapted to the constriction groove 1. When its outer side is engaged with the constriction groove 1, the connecting piece 302 is engaged with the end face of the segment beam web 12, thereby ensuring that the inner lining steel plate unit 3 is stably installed on the constriction groove 1.

[0063] The inner lining steel plate unit 3 also includes a positioning hole 303 disposed on the connecting piece 302 and used to pass through the prestressed steel bar 17.

[0064] In this embodiment, the prestressed steel bar 17 is inserted into the inner lining steel plate unit 3, which can further improve the installation stability of the inner lining steel plate unit 3.

[0065] The inner lining steel plate unit 3 also includes an inner lining steel plate insertion endpoint indicator 304 disposed on the inner lining plate 301 at the end position and used to receive the blocking effect of the protrusion 14 on the top plate 11 or bottom plate 13 of the segment beam.

[0066] In this embodiment, the insertion endpoint indicator 304 of the inner lining steel plate can be regarded as a "special" connecting piece 302 that does not require connecting two adjacent inner lining plates 301. The insertion installation direction of the inner lining steel plate unit 3 is perpendicular to the web plate 12 of the segmental beam, i.e., the insertion installation direction b. At this time, the front end side of the insertion endpoint indicator 304 of the inner lining steel plate in this direction can uniquely confirm the correct installation position of the inner lining steel plate unit 3 by abutting against the protrusion 14 on the top plate 11 or bottom plate 13 of the segmental beam.

[0067] When the inner lining steel plate is inserted and the endpoint indicator 304 abuts against the protrusion 14, the thickness of the segmental beam web 12 is roughly aligned with the width of the inner lining steel plate unit 3 towards the center, ensuring that the latter can be centered on the constriction groove 1. Accordingly, the width of the inner lining steel plate unit 3 can be greater than or slightly less than the thickness of the segmental beam web 12.

[0068] Among them, the protrusion 14 that can be used to block the insertion of the inner lining steel plate into the endpoint indicator 304 is two of the protrusions 14 in a row on the top plate 11 or bottom plate 13 of the segmental beam.

[0069] It should be noted that during the assembly of the segmental beam, the protrusion 14 and groove 15 are inserted first, then the inner steel plate unit 3 is installed, followed by the insertion and engagement of the three-section shear key unit 2, and finally the prestressed steel bars 17 are installed and tensioned.

[0070] Therefore, before the installation of the inner lining steel plate unit 3 on one side of the groove 15, the protrusion 14 on another segment beam has already been inserted into the groove 15, so the inner lining steel plate unit 3 on this side can also obtain the end position indication function of the protrusion 14 when it is installed.

[0071] The positioning hole 303 is provided on the endpoint indicator piece 304 for inserting the inner lining steel plate.

[0072] In this embodiment, the endpoint indicator 304 for inserting the inner lining steel plate can also be inserted into the prestressed steel bar 17, further improving the installation stability of the inner lining steel plate unit 3.

[0073] Each segmental beam web 12 is provided with 4-8 uniformly spaced constriction grooves 1.

[0074] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various modifications can be made without departing from the spirit of this application. These are non-inventive modifications and are protected by patent law as long as they are within the scope of the claims of this application.

Claims

1. A segmental precast bridge, comprising a segmental beam top plate (11), a segmental beam web plate (12), a segmental beam bottom plate (13), protrusions (14), grooves (15), prestressed ducts (16), and prestressed steel bars (17), characterized in that: It also includes a constriction groove (1) set on the end face of the web (12) of the segmental beam, a three-segment shear key unit (2) that engages with the constriction groove (1) and is used to connect the two segmental beams laterally, and an inner steel plate unit (3) set on the constriction groove (1) and used to engage the three-segment shear key unit (2).

2. A segmental assembled bridge according to claim 1, characterized in that: On a section parallel to the web (12) of the segmental beam, the cross-sectional shape of the constriction groove (1) includes a circular region or an isosceles trapezoidal region.

3. A segmental assembled bridge according to claim 1, characterized in that: The three-segment shear key unit (2) includes two transverse tensile blocks (201) respectively disposed on two corresponding constriction grooves (1) of two adjacent segment beams, and a central connecting plate (202) disposed on the two transverse tensile blocks (201).

4. A segmental assembled bridge according to claim 3, characterized in that: The three-segment shear key unit (2) also includes a fillet (203) disposed between the transverse tensile block (201) and the central connecting plate (202) to alleviate the stress concentration on the shear key.

5. A segmental assembled bridge according to claim 3, characterized in that: The thickness of the central connecting plate (202) is ≥2.0cm.

6. A segmental assembled bridge according to claim 3, characterized in that: The inner lining steel plate unit (3) includes an inner lining piece (301) disposed in the constriction groove (1) and used to engage the transverse tensile block (201), and a connecting piece (302) disposed on two adjacent inner lining pieces (301) and attached to the end face of the web plate (12) of the segmental beam.

7. A segmental assembled bridge according to claim 6, characterized in that: The inner lining steel plate unit (3) also includes a positioning hole (303) disposed on the connecting piece (302) and used to pass through the prestressed steel bar (17).

8. A segmental assembled bridge according to claim 7, characterized in that: The inner lining steel plate unit (3) also includes an inner lining steel plate insertion endpoint indicator (304) disposed on the inner lining plate (301) at the end position and used to receive the blocking effect of the protrusion (14) on the top plate (11) or bottom plate (13) of the segment beam.

9. A segmental assembled bridge according to claim 8, characterized in that: The positioning hole (303) is provided on the end point indicator (304) for inserting the inner lining steel plate.

10. A segmental assembled bridge according to claim 1, characterized in that: The web (12) of a single segmental beam is provided with 4-8 uniformly spaced constriction grooves (1).

Images