A transversely prestressed bridge widening structure

Abstract

The present application belongs to the technical field of bridge engineering, and particularly relates to a bridge widening structure form suitable for a bridge with transverse prestress, comprising a box girder of an original bridge and a box girder of a new bridge, the top of the web plate of the box girder of the new bridge is overlapped with the flange plate of the box girder of the original bridge and is fixedly connected through vertical prestressed steel bars of the box girder of the new bridge, so that the two become a common force-bearing whole, the box girder of the original bridge and the box girder of the new bridge are fixed through pouring of high-ductility concrete at the upper part of the joint of the bridge deck, and the rest positions are poured with ordinary concrete pavement layers. The present application has the beneficial effects that the vertical prestressed steel bars of the new bridge are used as anchoring connecting pieces, the cantilever end of the flange plate of the original bridge is connected with the box girder of the new bridge, the new and old bridges are integrally and commonly force-bearing, and the durability and driving comfort of the structure are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of bridge engineering, and particularly relates to a bridge widening structure suitable for a bridge with transverse prestress. BACKGROUND

[0002] With the rapid development of social economy in China, the traffic volume of highway network increases year by year. This makes a large number of early built bridges difficult to meet the current traffic operation demand, and thus needs to be reconstructed to improve the traffic carrying capacity. Considering both economy and practicability, if the bridge is rebuilt, the cost will be increased, which requires widening and reinforcing the original bridge on the basis of the original bridge to effectively utilize the structure of the original bridge and fully play the economic value under the premise of ensuring the safety and reliability of the bridge.

[0003] At present, for widening the large cantilever box girder bridge with transverse prestress, the end of the flange plate cannot be chiseled off and then connected to the new bridge by anchoring, and the widening method of only continuously paving the bridge deck is often adopted. When the superstructures of the new and old bridges are not connected, the overall stress is poor, and cracks are prone to occur at the joint of the bridge deck, affecting the safety of driving.

[0004] Chinese patent CN 104631348 A discloses a transverse widening splicing structure of a three-way prestressed concrete continuous box girder bridge. A transverse splicing stiffening rib is arranged between the new and old box girder webs at a certain distance, and the new and old main girders are connected together. Meanwhile, the flange plates of the new and old box girders are separated, and a plate type rubber belt is paved above the separation joint. The plate type rubber belt is fixed on the flange plate by bolts, and the top surface of the rubber belt is flush with the bridge deck pavement layer. This transverse splicing method not only overcomes the shortcoming that the flange plate of the three-way prestressed concrete box girder cannot be chiseled off, but also avoids the difficulty of transversely anchoring the reinforcement at the end of the flange plate, and better solves the transverse splicing problem of the three-way prestressed continuous box girder bridge.

[0005] However, the structure of the superstructure splicing part of the new and old box girders is not actually connected together, but is connected by the plate type rubber belt. Although the built-in reinforcement of the stiffening rib and the anchor bolt are increased, the overall stress is still poor, and cracks are prone to occur at the joint of the bridge deck, which needs to be further improved. SUMMARY

[0006] In order to overcome the shortcomings of the prior art, the present application provides a bridge widening structure suitable for a bridge with transverse prestress. The vertical prestressed reinforcement of the new bridge is used as an anchoring connecting piece, and the end of the flange plate of the original bridge is connected to the box girder of the new bridge, so that the new and old bridges are jointly stressed, and the durability and driving comfort of the structure are improved.

[0007] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0008] The application discloses a structure form suitable for a bridge widening structure with transverse prestress, which comprises a box girder of an original bridge and a box girder of a new bridge, the top of the web plate of the box girder of the new bridge is overlapped with the flange plate of the box girder of the original bridge, and the two are fixedly connected through vertical prestress steel bars of the box girder of the new bridge, so that the two become a whole under common stress; the original bridge and the new bridge are fixed through pouring high ductile concrete at the upper part of the joint of the bridge deck, and the rest part is poured with common concrete pavement.

[0009] Preferably, the upper part of the web plate of the new bridge is reserved with a notch matched with the end of the flange plate of the original bridge, and the end of the flange plate of the original bridge is arranged on the notch of the top of the web plate of the new bridge.

[0010] The end of the flange plate of the original bridge is provided with a connecting hole, the connecting hole is staggered with the position of the transverse prestress steel bar of the flange plate of the original bridge, and is coincided with the vertical prestress hole of the web plate of the new bridge.

[0011] The vertical prestress steel bar of the new bridge passes through the connecting hole and the vertical prestress hole respectively, and the original bridge and the new bridge are connected after grouting.

[0012] Preferably, the vertical prestress hole of the new bridge is provided with a penetrating bellows, and the vertical prestress steel bar of the new bridge passes through the bellows.

[0013] Preferably, the local reinforcing support rib plate is fixedly connected with the end of the web plate of the new bridge near the vertical prestress steel bar below the flange plate of the original bridge, and the top plate of the local reinforcing support rib plate is consistent with the inclination angle of the flange plate of the original bridge and is tightly arranged.

[0014] Preferably, the root of the local reinforcing support rib plate is provided with a reserved bolt hole, and the local reinforcing support rib plate is fixedly connected with the new bridge through the reserved bolt hole and a bolt.

[0015] Preferably, the high ductile concrete is provided with an implanted steel mesh, and the high ductile concrete is connected with the common concrete pavement layer through the implanted steel mesh.

[0016] Preferably, the high ductile concrete and the common concrete pavement layer are provided with an asphalt concrete pavement layer above.

[0017] Preferably, the local reinforcing support rib plate, the vertical prestress hole of the new bridge and the vertical prestress steel bar of the new bridge are uniformly arranged in multiple along the longitudinal direction of the bridge.

[0018] The application further provides a construction method suitable for the structure form of the bridge widening structure with transverse prestress.

[0019] The first step is to close the original bridge box girder and the adjacent lane of the new bridge box girder construction, remove the guardrail of the original bridge box girder, and chisel off the concrete pavement within the width range of the flange plate of the original bridge box girder;

[0020] The second step is to drill connecting holes at the staggered positions of the transverse prestressed steel bars at the end of the flange plate of the original bridge box girder, and the drilling positions coincide with the vertical prestressed ducts of the web plate of the new bridge box girder; the corrugated pipes are arranged in the vertical prestressed ducts, the vertical prestressed steel bars are passed through the connecting holes and the corrugated pipes in the vertical prestressed ducts, and then the vertical prestressed steel bars are tensioned, anchored and grouted to connect the original bridge box girder and the new bridge box girder together;

[0021] The third step is to install a local reinforcing support rib plate under the flange plate of the original bridge box girder, the top plate of the local reinforcing support rib plate is consistent with the inclination angle of the flange plate of the original bridge box girder and is tightly pressed, and the root of the local reinforcing support rib plate is connected with the new bridge box girder through the reserved bolt holes and bolts;

[0022] The fourth step is to pour high ductility concrete along the longitudinal direction within a certain width above the overlapping position of the flange plate end of the original bridge box girder and the new bridge box girder, and implant the steel mesh inside to connect with the ordinary concrete pavement layer;

[0023] The fifth step is to pave asphalt concrete on the concrete pavement within the whole bridge range;

[0024] The sixth step is to restore the traffic after the construction is completed.

[0025] The bridge widening structure of the application is suitable for the widening of bridges with transverse prestressed steel bars, the vertical prestressed steel bars of the new bridge are used as anchoring connecting pieces to connect the end of the flange plate of the original bridge box girder and the new bridge box girder together, so that the new and old bridges are jointly stressed, the vertical prestressed ducts and vertical prestressed steel bars are arranged in multiple along the longitudinal direction of the bridge, and the durability and driving comfort of the overall bridge structure are improved. The vertical prestressed steel bars generate prestress through tensioning and have a certain elongation, which can adapt to the displacement between the flange plate of the original bridge box girder and the new bridge, and has a certain self-resetting effect. The vertical prestressed steel bars of the new bridge box girder are also used to fix the end of the flange plate of the original bridge box girder, the structure is simple, and the materials and costs of other anchoring connecting pieces are saved.

[0026] Meanwhile, the local reinforcing support rib plate is arranged below the end of the flange plate of the original bridge, which ensures the bearing capacity and safety of the flange plate of the original bridge box girder, and the structure of the local reinforcing support rib plate is simple and can be mass-produced in the factory. The high ductility concrete can adapt to the displacement between the end of the flange plate of the original bridge box girder and the new bridge within a certain range, avoid the generation of longitudinal cracks, and reflect on the upper asphalt concrete pavement layer.

[0027] The connecting mode of the application can connect the new and old bridge structures together under the premise of ensuring that the transverse prestressed steel bars are not damaged, fully utilize the anchoring effect of the vertical prestressed steel bars of the new bridge, and has simple structure and strong applicability. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is an embodiment structure diagram of the application;

[0029] Figure 2 The figure is a new and old bridge connecting position structure form plan view of the application.

[0030] In the figure: original bridge box girder 1, transverse prestressed steel bar 2, ordinary concrete pavement layer 3, high ductility concrete 4, new bridge box girder 5, local reinforcing support rib plate 6, bolt 7, vertical prestressed duct 8, vertical prestressed steel bar 9, asphalt concrete pavement layer 10. DETAILED DESCRIPTION

[0031] In the description of the application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two components. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0032] In order to make the purpose, technical scheme and advantages of the application more clear, the application will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0033] The application provides a bridge widening structure form suitable for having transverse prestress, which comprises an original bridge box girder 1 and a new bridge box girder 5, the original bridge box girder 1 is provided with a transverse prestressed steel bar 2 on a flange plate, the new bridge box girder 5 is provided with a vertical prestressed duct 8 on a web plate, and a vertical prestressed steel bar 9 is located in the vertical prestressed duct 8.

[0034] As Figure 1 And Figure 2As shown, the bridge widening structure of the embodiment connects the top of the web plate of the new bridge box girder 5 and the flange plate of the original bridge box girder 1 together, uses the vertical prestressed duct 8 and the vertical prestressed steel bar 9 of the new bridge box girder 5 as the anchoring connecting member for connecting the new and old bridges, and connects the two into a common force-bearing whole through the vertical prestressed steel bar 9 of the new bridge box girder 5; meanwhile, high ductility concrete 4 is poured above the bridge deck overlap joint between the original bridge box girder 1 and the new bridge box girder 5, ordinary concrete pavement layer 3 is poured at the remaining positions, and local reinforcing support rib plates 6 are arranged to reinforce and support the original bridge box girder 1, so that the bridge has durability and driving comfort after widening.

[0035] In the embodiment, in order to realize the overlap of the top of the web plate of the new bridge box girder 5 and the flange plate of the original bridge box girder 1, a notch is reserved on the upper part of the web plate of the new bridge box girder 5, the end of the flange plate of the original bridge box girder 1 is arranged on the notch at the top of the web plate of the new bridge box girder 5, and the notch is attached to the end of the flange plate of the original bridge box girder 1. The web plate of the new bridge box girder 5 can provide vertical support for the end of the flange plate of the original bridge box girder 1.

[0036] In the embodiment, in order to connect the new bridge box girder 5 and the original bridge box girder 1 into a whole structure, a hole, i.e. a connecting hole, is drilled at a position where the end of the flange plate of the original bridge box girder 1 is staggered with the transverse prestressed steel bar 2, and the position of the connecting hole coincides with the vertical prestressed duct 8 of the web plate of the new bridge box girder 5. A corrugated pipe (not marked in the figure) is arranged in the vertical prestressed duct 8, the vertical prestressed steel bar 9 passes through the upper and lower ducts (the connecting hole and the corrugated pipe in the vertical prestressed duct 8), and then is tensioned, anchored and grouted to connect the original bridge box girder 1 and the new bridge box girder 5 together. The vertical prestressed duct 8 and the vertical prestressed steel bar 9 can be arranged in multiple in the longitudinal direction of the bridge, and through the fastening effect of the vertical prestressed steel bar 9, the structures of the new and old bridges are connected into a whole common force-bearing structure, and the driving comfort is improved.

[0037] In the embodiment, the vertical prestressed steel bar 9 generates prestress through tensioning, has a certain elongation, can adapt to the displacement between the flange plate of the original bridge box girder 1 and the new bridge box girder 5, and has a certain self-resetting effect. The vertical prestressed steel bar 9 of the new bridge box girder 5 is also used to fix the end of the flange plate of the original bridge box girder 1, the structure is simple, and the materials and costs of other anchoring connecting members are saved.

[0038] In the embodiment, the local reinforcing support rib plate 6 is arranged near the vertical prestressed reinforcement 9 below the flange plate of the original bridge box girder 1 (with the transverse prestressed reinforcement 2 staggered), the top plate of the local reinforcing support rib plate 6 has the same inclination angle as the inclination angle of the flange plate of the original bridge box girder 1 and is tightly abutted. The root of the local reinforcing support rib plate 6 is provided with a reserved bolt hole, the root of the local reinforcing support rib plate 6 is fixedly connected with the end of the web of the new bridge box girder 5 through the reserved bolt hole and the bolt 7, and the original bridge box girder 1 is reinforced and supported. In the embodiment, a group (two) of local reinforcing support rib plates 6 are arranged near each vertical prestressed reinforcement 9.

[0039] The local reinforcing support rib plate 6 of the embodiment has a simple structure, the angle of the top support plate can be determined according to the inclination angle of the flange plate of the original bridge box girder 1, and therefore the local reinforcing support rib plate 6 can be prefabricated in batches in the factory. When prefabricated, the bolt hole is reserved at the root of the local reinforcing support rib plate 6, and the bolt 7 is used for connection during installation, which can effectively improve the construction progress.

[0040] In the embodiment, the high ductile concrete 4 is longitudinally poured within a certain width above the lap joint of the end of the flange plate of the original bridge box girder 1 and the new bridge box girder 5, the steel bar net is implanted in the high ductile concrete 4, and the high ductile concrete 4 is connected with the ordinary concrete paving layer 3, the high ductile concrete 4 and the ordinary concrete paving layer 3 are provided with the asphalt concrete paving layer 10 above in the whole bridge range. The high ductile concrete 4 can adapt to the displacement between the end of the flange plate of the original bridge box girder 1 and the new bridge box girder 5 within a certain range, and the generation of longitudinal cracks is avoided from being mapped to the upper asphalt concrete paving layer 10.

[0041] The embodiment is suitable for the bridge widening structure with transverse prestressed reinforcement, and the specific construction method is as follows:

[0042] First step: close the original bridge box girder 1 and the new bridge box girder 5 to construct the adjacent lane, remove the guardrail of the original bridge box girder 1, and chisel off the concrete paving within the width range of the flange plate of the original bridge box girder 1;

[0043] Second step: drill the connecting hole at the position staggered with the transverse prestressed reinforcement of the end of the flange plate of the original bridge box girder 1, and make the drilling position coincide with the vertical prestressed hole 8 of the web of the new bridge box girder 5; arrange the bellows in the vertical prestressed hole 8, and then pass the vertical prestressed reinforcement 9 through the upper and lower holes (the connecting hole and the bellows in the vertical prestressed hole 8), then tension, anchor and grout, and connect the new and old bridges together;

[0044] Third step: install the local reinforcing support rib plate 6 below the flange plate of the original bridge box girder 1, the top plate of the local reinforcing support rib plate 6 has the same inclination angle as the inclination angle of the flange plate of the original bridge box girder 1 and is tightly abutted, and the root of the local reinforcing support rib plate 6 is connected with the new bridge box girder 5 through the bolt 7;

[0045] Fourth step: high ductility concrete 4 is poured in a certain width above the joint position of the original bridge box girder 1 flange plate end and the new bridge box girder 5 along the longitudinal direction, and the steel bar net is implanted in the interior to be connected with the ordinary concrete paving layer 3;

[0046] Fifth step: the asphalt concrete paving layer 10 is paved above the concrete paving in the whole bridge range;

[0047] Sixth step: the construction is completed, and the traffic is restored.

[0048] The above detailed description is made to the examples of the present application, but the content is only the preferred embodiments of the present application, and cannot be considered to limit the implementation range of the present application. Any equivalent changes and improvements made according to the application range of the present application should still belong to the patent coverage range of the present application.

Claims

1. A bridge widening structure suitable for transverse prestressing, characterized in that: The bridge includes the original bridge box girder and the new bridge box girder. The top of the web of the new bridge box girder overlaps with the flange of the original bridge box girder and is fixedly connected by the vertical prestressed steel bars of the new bridge box girder, making the two a whole that shares the load. The area above the overlap joint between the original bridge box girder and the new bridge box girder is fixed by pouring high-ductility concrete, while the remaining areas are covered with ordinary concrete pavement. The upper part of the web of the new bridge box girder has a groove reserved to fit the end of the flange plate of the original bridge box girder, and the end of the flange plate of the original bridge box girder is placed at the groove at the top of the web of the new bridge box girder. The original bridge box girder flange plate is provided with a connecting hole at its end. The connecting hole is offset from the position of the transverse prestressed steel bar of the original bridge box girder flange plate and coincides with the vertical prestressed duct of the web plate of the new bridge box girder. The vertical prestressed steel bars of the new bridge box girder pass through the connecting holes and the vertical prestressing ducts respectively, and after grouting, the original bridge box girder and the new bridge box girder are connected together.

2. The bridge widening structure suitable for transverse prestressed bridges according to claim 1, characterized in that: The vertical prestressing ducts of the new bridge box girder are equipped with corrugated pipes that pass through them, and the vertical prestressing steel bars of the new bridge box girder pass through the corrugated pipes.

3. The bridge widening structure according to claim 1, characterized in that: Below the flange of the original bridge box girder and near the vertical prestressed steel bars, there is a locally reinforced support rib plate that is fixedly connected to the web of the new bridge box girder. The top plate of the locally reinforced support rib plate has the same inclination angle as the flange of the original bridge box girder and is pressed tightly against it.

4. A bridge widening structure suitable for transverse prestressing as described in claim 3, characterized in that: The root of the partially reinforced support rib is provided with a reserved bolt hole, and the partially reinforced support rib is fixedly connected to the new bridge box girder through the reserved bolt hole and bolts.

5. A bridge widening structure suitable for transverse prestressing as described in claim 1, characterized in that: The high-ductility concrete has an embedded steel mesh inside, and the high-ductility concrete is connected to the ordinary concrete pavement layer through the embedded steel mesh.

6. A bridge widening structure suitable for transverse prestressing as described in claim 1, characterized in that: An asphalt concrete pavement layer is provided above both the high-ductility concrete and the ordinary concrete pavement layers throughout the entire bridge.

7. A bridge widening structure suitable for transverse prestressing as described in claim 3, characterized in that: The locally reinforced support ribs and the vertical prestressed steel bars of the new bridge box girder are uniformly arranged along the longitudinal direction of the bridge.

8. A construction method for a bridge widening structure with transverse prestressing, as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Close the adjacent lanes for the construction of the original bridge box girder and the new bridge box girder, remove the guardrails of the original bridge box girder, and chisel away the concrete pavement within the width of the flange plate of the original bridge box girder. Step 2: Drill connection holes at positions offset from the transverse prestressed steel bars at the ends of the original bridge box girder flanges. The drilling positions coincide with the vertical prestressing ducts in the web of the new bridge box girder. Arrange corrugated pipes in the vertical prestressing ducts, pass the vertical prestressed steel bars through the connection holes and the corrugated pipes in the vertical prestressing ducts, then tension and anchor them and grout them to connect the original bridge box girder with the new bridge box girder. Step 3: Install a local reinforcing support rib plate under the original bridge box girder flange plate. The top plate of the local reinforcing support rib plate is inclined at the same angle as the original bridge box girder flange plate and is tightened. The root of the local reinforcing support rib plate is connected to the new bridge box girder through reserved bolt holes and bolts. Step 4: Within a certain width above the overlap position between the end of the original bridge box girder flange and the new bridge box girder, pour high-ductility concrete longitudinally, and embed steel mesh inside it to connect with the ordinary concrete pavement layer. Step 5: Lay asphalt concrete over the concrete pavement throughout the entire bridge area; Step 6: Construction completed, traffic restored.

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