An anti-overturning connection structure between a single-column pier and a main beam

Abstract

The present invention relates to a connection structure between a single-column pier and a main girder for anti-overturning, belonging to the technical field of bridge structures. The connection structure includes a convex plate extending upward from the top surface of the pier, bearings located on both sides of the convex plate in the transverse direction of the bridge, and a groove corresponding to the convex plate on the main girder. The groove is along the longitudinal direction of the bridge, the convex plate is inserted into the groove, and the convex plate and the groove can slide relative to each other along the longitudinal direction of the bridge, and the gap between them in the transverse direction of the bridge is very small. While ensuring that the main girder can slide on the bearing, the present invention resists the overturning of the main girder on the single-column pier by restricting the sliding of the main girder with a large displacement in the transverse direction of the bridge and preventing the rotation of the main girder. This connection structure does not require a capping beam to be provided at the top of the single-column pier, and is relatively simple and concealed compared with other existing anti-overturning structural forms, can maintain a simple appearance of the single-column pier, save materials, and can further reduce the workload on site through prefabricated and assembled construction.

Description

Technical Field

[0001] The present invention relates to a single-column pier bridge, and particularly to a connection structure between a single-column pier and a main beam with anti-overturning function, belonging to the technical field of bridge structures. Background Art

[0002] Single-column pier bridges generally adopt the form of continuous box girder bridges. Due to their advantages such as land saving, visual transparency, smooth lines, and beautiful appearance, they are widely used in highway bridges. Because of their simple and smooth appearance and small occupation of the space under the bridge, and combined with the overall bridge with light and beautiful appearance, they are widely used in urban bridges and ramp of highway interchange. However, in recent years, with the development of China's economy, the traffic flow and vehicle load have been continuously increasing. Due to overweight vehicle partial load and drivers' lack of safe driving knowledge, a series of single-column pier bridge overturning and collapse accidents have occurred continuously, making the safety problem of single-column pier bridges increasingly prominent.

[0003] For existing single-column pier bridges, inspections and reinforcements have been carried out everywhere to enhance the safety of bridge use. The main reinforcement measures include adding columns beside the original piers, or adding capping beams on the top of the original piers, or adding diagonal braces between the two wings of the box girder and the piers. After reinforcement, the bridges lose their original simple advantages and are also less attractive in terms of aesthetics. Currently, for newly designed bridges, there has been a phenomenon of minimizing or even banning the use of single-column pier bridges. Summary of the Invention

[0004] In order to overcome the deficiencies in the prior art, the present invention develops a connection structure between a single-column pier and a main beam with anti-overturning function, aiming to provide a design scheme for single-column pier bridges, which can enhance the anti-overturning ability of single-column pier bridges while maintaining their advantages such as simplicity and beauty.

[0005] The technical solution proposed by the present invention is a connection structure between a single-column pier and a main beam with anti-overturning function, including a main beam, a single-column pier, a bearing, a groove, and a convex plate. The groove is located at the bottom of the main beam and opens downward. The opening is located on the lower surface of the main beam bottom plate, and the long side is along the longitudinal axis direction of the main beam. The convex plate extends upward from the top surface of the pier and extends into the groove. The long side of the convex plate is along the longitudinal axis direction of the bridge. The convex plate and the groove can move relatively longitudinally, while the relative transverse movement is restricted.

[0006] Preferably, there are at least two convex plates on the single-column pier, and the main beam has corresponding grooves.

[0007] Preferably, the bridge is a curved bridge, and its longitudinal axis is a curve.

[0008] Preferably, the cross-section of the top of the single-column pier is the same as that of the middle part.

[0009] Preferably, the gap between the two side surfaces of the transverse bridge direction of the convex plate and the side wall of the corresponding groove is less than 5 mm.

[0010] Preferably, a flat jack is placed on the upper end surface of the convex plate for jacking up the main beam when replacing the bearing.

[0011] Preferably, the groove is made of steel plates, and the convex plate is also made of steel; the steel for making the groove and the convex plate is weathering steel; the single-column pier is a concrete-filled steel tube member.

[0012] Preferably, the main beam has a diaphragm at the single-column pier; the groove intersects with the diaphragm, and there is a local strengthening structure around the groove.

[0013] Preferably, the single-column pier is a concrete member, and the lower end of the convex plate is connected with a pre-buried section pre-buried in the single-column pier; the outer side surface of the pre-buried section is connected with anchor bars.

[0014] Preferably, the convex plate is formed by connecting a plurality of webs along the longitudinal direction of the H-shaped steel in the transverse bridge direction, and the adjacent flange ends are welded; the top of the convex plate is a steel plate, and the steel plate is welded to the upper ends of the lower H-shaped steels.

[0015] The beneficial effects of the present invention include the following aspects:

[0016] (1) The connection structure between the single-column pier and the main beam in the present invention can prevent the lateral sliding of the main beam at the pier top when the main beam has an overturning tendency; under the action of eccentric load, the forces on the bearings are no longer uniform. The edge of the bearing on the side where the heavy vehicle is located is compressed and deformed greatly, and the main beam has a tendency to rotate. In this case, the top of the convex plate will contact the groove wall, and the convex plate will exert pressure on the groove wall. This pressure generates an anti-overturning moment on the main beam to prevent the development of rotation. Preventing the sliding and rotation of the main beam can resist the overturning of the main beam on the single-column pier. Because the overturning of the single-column pier is caused by the rotation and sliding of the main beam. This process is generally caused by eccentric load making the bearing forces uneven, or even one side being off the ground, the main beam deflecting to a certain extent. When the vertical pressure on one side of the bearing exceeds the design strength of the bearing, the bearing will be damaged, and the lower surface of the beam body will touch the edge of the pier top, causing the pier to bend laterally away from the overloaded side. If the strength of the pier is not large enough, the top section of the pier will break, resulting in the collapse of the bridge; if the pier is not high and the strength is sufficient, the pier will not be damaged, but due to the increase in the rotation angle of the main beam, the main beam will slide. Thus, it can be seen that the main beam overturns through rotation and sliding. The solution in the present application can effectively prevent the occurrence of overturning.

[0017] (2) This connection structure does not require a capping beam to be provided on the top of the single-column pier, and can maintain a simple appearance of the single-column pier.

[0018] (3) The technical solution in the present application retains all the advantages of the single-column pier bridge.

[0019] (4) The upper end surface of the convex plate of this connection structure can place a flat jack, which is convenient for jacking up the main girder when needed to replace the bearing.

[0020] (5) The groove of the main girder intersects with the powerful diaphragm wall. A local strengthening structure is adopted around the groove, which can not affect the function of the diaphragm wall and does not weaken the mechanical properties of the main girder.

[0021] (6) The pier adopts a concrete-filled steel tube member. The convex plate can be connected and fixed with a steel section before pouring concrete, which is convenient for the positioning of the convex plate during construction; since the construction of the pier no longer requires additional formwork erection, it facilitates the construction and speeds up the construction progress; the concrete-filled steel tube member has high shear and flexural strength, and the phenomenon of the pier column breaking first will not occur; using the concrete-filled steel tube member as a single-column pier also enhances the ability of the pier to resist the impact damage of the vehicles under the bridge.

[0022] (7) Through prefabricated and assembled construction, the on-site workload is further reduced to achieve rapid construction.

[0023] (8) The technical solution in this application can also be used for the renovation of existing single-column pier bridges. For example, for an existing single-column pier steel bridge, the steel main girder can be hoisted and removed. A steel sleeve can be added at the top of the single-column pier to connect with the pier body. The top of the steel sleeve is a steel plate, and there are protrusions buckling on the cushion stone on the upper surface of the steel plate, and a convex plate is welded. Epoxy resin glue can be poured into the gap between the steel plate and the original pier top; the steel main girder is structurally renovated by adding a groove; then the steel main girder is hoisted and installed. Description of the Drawings

[0024] Figure 1 Side view schematic diagram of the bridge at the single-column pier;

[0025] Figure 2 Cross-sectional schematic diagram of the bridge passing through the center of the bearing;

[0026] Figure 3 Longitudinal sectional schematic diagram of the bridge passing through the central plane of the convex plate;

[0027] Figure 4 Figure 2 Side view schematic diagram of the A-A section in;

[0028] Figure 5 Figure 3 Top view schematic diagram of the B-B section in;

[0029] Figure 6 Vertical sectional schematic diagram of the convex plate;

[0030] Figure 7 Cross-sectional schematic diagram of the convex plate;

[0031] Figure 8Schematic diagram of partial reinforcement in the transverse and longitudinal vertical sections of the groove;

[0032] Figure 9 Schematic diagram of partial reinforcement in the longitudinal and transverse vertical sections of the groove;

[0033] Figure 10 Schematic diagram of the longitudinal section at the top of the convex slab.

[0034] In the figure: pier 1, bearing pad 2, bearing 3, main girder 4, anti-collision guardrail 5, groove 6, convex slab 7, middle web 8, transverse additional prestressed tendon 9, longitudinal additional prestressed tendon 10, diaphragm 11, side web 12, secondary side web 13, anchor bar 14, end plate 15, H-shaped steel 16, steel shell 17, transverse cross bar tendon 18, longitudinal cross bar tendon 19, flat jack 20, top plate 21. Specific implementation mode

[0035] The following uses specific specific examples to illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content described in this specification. The present invention can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0036] Among them, the drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and cannot be understood as a limitation to the present invention; in order to better illustrate the embodiments of the present invention, some components in the drawings will be omitted, enlarged or reduced, which do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0037] In the drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or position relationship, it is based on the orientation or position relationship shown in the drawings, and 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. Therefore, the terms describing the position relationship in the drawings are only for illustrative purposes and cannot be understood as a limitation to the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] The single-column pier bridge in this embodiment is a three-span reinforced concrete continuous box girder, a straight bridge, and both piers are single-column piers, as shown in Figures 1 - 5。The pier 1 is a single-column pier and is a concrete-filled steel tube member with a steel tube wall thickness of 14 mm and an outer diameter of 1228 mm; the cross-section of the main girder 4 is a single-box four-chamber type with a beam height of 900 mm. An anti-collision guardrail 5 is installed on the main girder 4, and the top surface of the pier 1 is a bearing pad stone 2. The convex plate 7 extends upward from the top surface of the pier 1 and extends into the groove 6; the groove 6 is located at the bottom of the main girder 4 and opens downward, and the opening is located on the lower surface of the bottom plate of the main girder 4, and the long side is along the longitudinal bridge direction; in the transverse bridge direction, bearings 3 are installed on both the left and right sides of the convex plate 7. The convex plate 7 is welded by an H-shaped steel 16 and an end plate 15, see Figure 7 。The specification of the H-shaped steel 16 is 200×204×12×12, the thickness of the end plate 15 is 12 mm, and the length of the cross-section of the convex plate 7 after welding is 640 mm. The height of the convex plate 7 extending out of the top surface of the bearing pad stone 2 is 600 mm. The length of the groove 6 is 860 mm, the width is 208 mm, and the depth is 615 mm. A flat jack 20 is placed on the top surface of the convex plate 7. The groove 6 is in the middle web 8 and is made of a steel shell 17 with a wall thickness of 12 mm, and anchor bars 14 are also welded on the outer side, see Figure 8 。The lower end of the convex plate 7 is connected with a pre-embedded section, see Figure 6 , and the convex plate 7 is welded to the inner wall of the steel tube of the pier 1 through a steel section support, and anchor bars 14 are welded on the pre-embedded section of the convex plate 7.

[0039] There is a diaphragm 11 at the pier 1 of the main girder 4, and the designed thickness of the diaphragm 11 is 300 mm, and the thickness of the diaphragm 11 at the groove 6 is 500 mm. The thickness of the diaphragm 11 around the groove 6 is linearly variable, see Figure 4 and Figure 5 。The designed thickness of the side web 12, the secondary side web 13 and the middle web 8 is 250 mm, and the thickness of the middle web 8 near the diaphragm 11 is also linearly variable. Such a design can locally strengthen the groove 6.

[0040] Considering local strengthening of the groove 6 and being able to use the flat jack 20 on the convex plate 7 to jack up the main girder 4 to facilitate replacement of the bearing 3, transverse tie bars 18 and transverse additional prestressing tendons 9 are arranged in the diaphragm 11; longitudinal tie bars 19 (see Figure 9 ) and longitudinal additional prestressing tendons 10 are arranged in the middle web 8.

[0041] To further improve the shear and bending strength of the convex plate 7, high-strength grouting material is poured into the cavity formed by the H-shaped steel 16.

[0042] To reduce the stress concentration degree when the side edges at the top of the convex plate 7 are squeezed against the side walls of the groove 6 when the main girder 4 rotates, the two side edges at the top of the convex plate 7 are rounded. Before assembling the convex plate 7, the top of the end plate 15 and the two ends of the top plate 21 are bent, and the flange plates of the corresponding H-shaped steel 16 at the two ends are cut accordingly, and then welded after assembly, seeFigure 10 To improve the strength of the convex plate 7, grout holes are drilled in the flange plate of the H-shaped steel 16 and the top plate 21, and high-strength cement grout is injected into the internal cavity of the convex plate 7 to ensure it is full.

[0043] The main beam 4 of this bridge is constructed by the segment prefabrication and installation method, which can speed up the construction progress.

[0044] This technical solution maintains the advantages such as the simple appearance of the single-column pier bridge, and can resist the rollover of the bridge caused by the eccentric load of overloaded vehicles, greatly improving the safety of the single-column pier bridge and providing a solution for the continued application of the single-column pier bridge at suitable locations.

Claims

1. An anti-overturning connection structure between a single-column pier and a main girder, comprising a main girder, a single-column pier, a bearing, a groove, and a convex plate, characterized in that: The main beam has a diaphragm at the single-column pier; the groove is located at the bottom of the main beam and opens downward, and the opening is located on the lower surface of the main beam bottom plate, with the long side along the longitudinal axis direction of the main beam; the groove intersects with the diaphragm, and there is a local strengthening structure around the groove; the convex plate extends upward from the top surface of the single-column pier and extends into the groove, and the long side of the convex plate is along the longitudinal axis direction of the bridge; the convex plate and the groove can move relatively longitudinally, while the relative lateral movement is restricted; the groove is made of steel plates, and the convex plate is also made of steel; the convex plate is formed by connecting multiple webs in the transverse direction of the H-shaped steel along the longitudinal direction of the bridge, and the adjacent flange ends are welded; the top of the convex plate is a steel plate, and the steel plate is welded to the upper ends of the lower H-shaped steels; the gaps between the two side surfaces of the convex plate in the transverse direction and the corresponding groove side walls are less than 5 mm; a flat jack is placed on the upper surface of the convex plate, which is used to jack up the main beam when replacing the bearing.

2. The connection structure between the anti-overturning single-column pier and the main beam according to claim 1, characterized in that: There are at least two such convex plates on the single-column pier, and the main beam has corresponding grooves.

3. The connection structure between the anti-overturning single-column pier and the main girder according to claim 1, characterized in that: The bridge is a curved bridge, and its longitudinal axis is a curve.

4. The connection structure between the anti-overturning single-column pier and the main girder according to claim 1, characterized in that: The cross-section of the top of the single-column pier is the same as that of the middle part.

5. An anti-overturning connection structure between a single-column pier and a main beam as described in claim 1, characterized in that: The steel used to make the groove and the convex plate is weathering steel; the single-column pier is a concrete-filled steel tube member.

6. The connecting structure between the anti-overturning single-column pier and the main beam as described in claim 1, characterized in that: The single-column pier is a concrete member, and the lower end of the convex plate is connected with a pre-embedded section pre-embedded in the single-column pier; the outer side surface of the pre-embedded section is connected with anchor bars.

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