CN116122146A

CN116122146A - Bridge deck transition structure and construction method thereof

Info

Publication number: CN116122146A
Application number: CN202310086819.3A
Authority: CN
Inventors: 顾民杰; 吴万忠; 华晓勇
Original assignee: Shanghai Municipal Engineering Design Insitute Group Co Ltd
Current assignee: Shanghai Municipal Engineering Design Insitute Group Co Ltd
Priority date: 2023-01-19
Filing date: 2023-01-19
Publication date: 2023-05-16

Abstract

The invention belongs to the technical field of combined bridge deck structures, and particularly relates to a bridge deck transition structure and a construction method thereof. The transition structure changes the stiffening of the flat-bulb steel into an inverted T-shaped stiffening, vertical stiffening is additionally arranged below the inverted T-shaped stiffening bottom plate, and a concrete slab steel support is formed at the side of the reinforced concrete composite beam. In order to improve the bonding capacity of the bonding surface, measures such as prestress, U-shaped ribs, tensile shear nails, overlap joint between the ultra-high performance concrete layer and the concrete bridge deck are adopted, and stable transition of force transmission structure and rigidity is realized. The invention has the advantages of simple structure, convenient construction, firm and reliable joint surface, good durability and fatigue resistance, and the like.

Description

Bridge deck transition structure and construction method thereof

Technical Field

The invention belongs to the technical field of combined bridge deck structures, and particularly relates to a transition structure of a flat-bulb steel stiffening light combined bridge deck and a reinforced concrete combined beam concrete bridge deck and a construction method thereof.

Background

The stiffening rib forms commonly used for the steel bridge deck comprise U-shaped ribs in a closed form, I-shaped ribs in an open form, T-shaped ribs, flat-bulb steel and the like. The U-shaped rib has larger rigidity, can reduce the stress of a second system and a third system of the steel bridge deck, has the greatest application in the large-span steel bridge deck, but has the defects of large steel consumption, large internal welding difficulty and the like, and has more fatigue and easy damage details, so that the cracking problem is easy to occur in the operation period. The traditional steel-concrete composite beam can solve the problem that the steel bridge deck is easy to crack, but the bridge type is limited by the span and has limited applicability.

In recent years, the development of light combined bridge deck structures is rapid, and novel bridge decks represented by steel ultra-high performance concrete combined structures are promoted. The bridge deck has the advantages that the rigidity of the bridge deck is effectively improved and the stress of the bridge deck is lower by means of the superposition of the steel panel and the ultra-high performance concrete layer. At this time, the panel stiffening is more suitable for adopting the opening form, can keep higher bridge deck rigidity, has reduced the steel consumption again and has welded the degree of difficulty, and the structure also obtains further simplification. In the open stiffening, the flat-bulb steel has reasonable geometric shape and high material utilization rate, and is more suitable for a large-span steel bridge surface structure. However, the construction cost of such composite deck structures is higher than that of conventional reinforced concrete composite beams.

On the other hand, multi-span bridges often employ a smaller side-to-side ratio due to terrain, environmental or economic factors, etc. At this time, in order to balance the load of the side midspan, the stress is improved, and meanwhile, in consideration of economy, a light combined structure with smaller weight can be adopted in the main span, and a traditional reinforced concrete combined beam concrete bridge deck is adopted in the side span. The structural system adopting the arrangement has less application in China, and the key for guaranteeing the stress performance of the structural system is to develop a reasonable bridge deck transition structure, and the reliable technology of the structure is lacking at present.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects of the prior art and providing the combined bridge deck transition structure which is safe, reliable, reasonable in stress and simple in structure.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

the bridge deck transition structure is characterized in that a beam at a joint surface is arranged at the joint surface of a light-duty combined bridge deck reinforced by flat-bulb steel and a concrete bridge deck of a steel-concrete combined beam, an inverted T-shaped stiffening bottom plate is welded below the flat-bulb steel in the transition structure, a vertical stiffening is additionally arranged below the inverted T-shaped stiffening bottom plate, and a concrete slab steel support is formed at the side of the steel-concrete combined beam; the method comprises the steps of arranging prestressed steel bars between concrete bridge deck boards, extending the prestressed steel bars to the side of a light combined bridge deck, anchoring between stiffening plates under prestressed anchors, arranging a beam at a tensioning end and a beam at an anchoring section at a prestressed tensioning end and an anchoring section respectively, and improving the tensile capacity of an interface; the beam at the joint surface and the concrete bridge deck are provided with tensile U-shaped ribs and tensile shear nails at the joint to ensure effective combination between the two bridge decks.

Further, the lightweight composite deck comprises an ultra-high performance concrete layer, the rigid facing layer below the ultra-high performance concrete layer having a thickness of less than 10cm.

Further, the concrete bridge deck of the steel-concrete composite beam is in a composite structure form comprising a steel structure and a concrete panel, wherein the concrete panel is a precast slab or a cast-in-situ slab, and the steel structure is an integral box beam, a plurality of box beams, a slab beam and a grid beam.

Further, the ultra-high performance concrete layer of the light combined bridge deck is extended into the range of 50 cm-100 cm of the concrete bridge deck of the steel-concrete combined beam, so that the effective transition of force transmission structure and rigidity is realized.

Furthermore, the concrete slab steel bearing below the inverted T-shaped stiffening bottom plate adopts a variable height shape along the force transmission direction, so that the effective transition of the force transmission structure and the rigidity of the stiffening plate is realized.

Further, the cross beam at the stiffening transition part is provided with a welding hole, the stiffening of the flat-bulb steel is continuous in length at the position of the cross beam, and the fatigue resistance of the welding node is greatly improved.

Further, the flat-bulb steel stiffening and the concrete slab steel bearing below the flat-bulb steel stiffening and the inverted T-shaped stiffening bottom plate are welded to be 50 cm-100 cm in length along the force transmission direction, so that the effective transition of the force transmission structure and the rigidity of the two stiffening ribs is ensured.

Further, the distance between the cross beam at the stretching end of the prestressed reinforcement and the cross beam at the anchoring end is 300 cm-400 cm, so that a force transmission transition area of the concrete bridge deck is formed.

Further, an under-anchor stiffening plate is arranged below the light combined bridge deck, an anchor backing plate is arranged around the under-anchor stiffening plate, and the under-anchor stiffening plate and the steel top plate form closed stiffening to disperse under-anchor stress and form grouting space, so that the durability of the prestressed tendons is improved; the prestressed reinforcement is positioned in the closed stiffening structure.

Preferably, the prestressed reinforcement is a prestressed steel strand, a thick reinforcement or a parallel wire bundle.

The invention has the following beneficial effects:

compared with the prior art, the invention has the advantages of simple structure, clear stress and convenient construction, can effectively ensure the stress and durability of the mixed bridge deck, and ensures the effective combination between the two bridge decks by utilizing multiple measures such as shear nails, U-shaped ribs, the overhanging of the longitudinal ribs of the ultra-high performance concrete layer, prestressing and the like, thereby realizing the stable transition of the force transmission structure and the rigidity.

Drawings

FIG. 1 is a schematic elevation view of a transition structure according to an embodiment of the present invention;

FIG. 2 is a top plan view of an embodiment of the present invention taken along the A-A direction;

FIG. 3 is a cross-sectional view along the direction B-B of an embodiment of the present invention;

FIG. 4 is a cross-sectional view along the direction C-C of an embodiment of the present invention;

FIG. 5 is a partial enlarged view of area D according to an embodiment of the present invention;

FIG. 6 is an enlarged view of a portion of area E according to an embodiment of the present invention;

fig. 7 is an enlarged view of a portion of a U-shaped rib according to an embodiment of the present invention.

The numbers in the figure are as follows:

1. an ultra-high performance concrete layer; 2. a concrete deck; 3. a steel top plate; 4. stiffening the flat-bulb steel; 5. inverted T-shaped stiffening webs; 6. inverted T-shaped stiffening bottom plates; 7. bearing the concrete slab steel; 8. a cross beam is arranged at the joint surface; 9. a beam at the stretching end; 10. a beam at the stiffening transition part; 11. tensile U-shaped ribs (at the joint surface); 12. tensile shear pins (at the joint surface); 13. prestress steel bars; 14. an anchor backing plate; 15. anchor lower stiffening plate; 16. and the beam is positioned at the anchoring end.

Detailed description of the preferred embodiments

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the illustrations provided in the following embodiments merely illustrate the basic idea of the present invention by way of illustration, and the following embodiments and features in the embodiments may be combined with each other without conflict. Wherein the drawings are for illustrative purposes only and are shown in schematic, non-physical, and not intended to limit the invention; for the purpose of better illustrating embodiments of the invention, certain elements of the drawings may be omitted, enlarged or reduced and do not represent the size of the actual product; some well known structures in the drawings and omission of the description thereof will be understood by those skilled in the art.

As shown in fig. 1 and 2, the invention relates to a transition structure of a light-duty composite bridge deck with steel-concrete composite beam, wherein main components related to the light-duty composite bridge deck side are an ultra-high performance concrete layer 1, a steel top plate 3 and a light-duty steel stiffening 4; the main component involved in the steel-concrete composite girder side is a concrete deck slab 2. The light combined bridge deck flat-bulb steel stiffening 4 is welded with the inverted T-shaped stiffening bottom plate 6 gradually continuously through a stiffening transition part cross beam 10, the cross beam 9 at the prestress tensioning end is changed into inverted T-

shaped stiffening

5 and 6, a vertical stiffening is welded below the bottom plate 6, and a bridge deck support 7 is formed at the side of the reinforced concrete combined beam. The cross beam 8 at the joint surface is arranged at the joint surface of the two bridge decks. Referring to the anchoring structure of the prestressed tendons on the light combined bridge deck side of fig. 6, in order to ensure the performance of the joint surface, the prestressed tendons 13 are adopted to pre-press the interface, the tensioning ends of the prestressed tendons are positioned on the light combined bridge deck side, and the cross beams 9 at the prestressed tensioning ends are arranged at the tensioning anchoring positions; the anchoring end is positioned on the concrete bridge deck side of the reinforced concrete composite beam, and the beam 16 at the prestressed anchoring end is arranged at the anchoring position. In order to further improve the tensile capacity of the joint surface, U-shaped ribs 11 and tensile welding nails 12 are welded on a beam web plate at the joint surface, and meanwhile, the ultra-high performance concrete layer 1 is extended to the range of 50 cm-100 cm of the concrete bridge surface.

The transition structure of the flat-bulb steel stiffening light combined bridge deck and the reinforced concrete combined beam concrete bridge deck of the embodiment adopts the following construction steps:

the first step, manufacturing a steel structure part in a factory, wherein the steel structure part comprises a longitudinal and transverse beam structure at two sides, a light combined bridge deck side steel top plate, flat-bulb steel, an inverted T-shaped stiffening web plate and a bottom plate;

secondly, applying steel-concrete composite Liang Jianli nails, light composite bridge deck shear nails, tensile shear nails at the joint interface, and welding U-shaped steel bars;

thirdly, constructing a concrete bridge deck plate on the side of the steel-concrete composite beam, wherein when the cast-in-situ bridge deck plate is adopted, a prestressed reinforcement pipeline is buried, and when the prefabricated bridge deck plate is adopted, the prestressed pipeline is reserved according to design files when the bridge deck plate is processed;

maintaining the concrete bridge deck, and tensioning a single end of the prestressed reinforcement at the side of the light combined bridge deck after the strength meets the tensioning condition; grouting a cavity formed by the anchored stiffening plate and the steel top plate after tensioning;

pouring a light combined bridge deck side ultra-high performance concrete layer, and roughening the combination range of the concrete bridge deck plate and the ultra-high performance concrete layer before pouring to improve the interface shearing resistance of the two materials;

and sixthly, curing the ultra-high performance concrete layer to finish the construction of the transition structure of the whole light combined bridge deck and the reinforced concrete combined beam concrete bridge deck.

Claims

1. A bridge deck transition structure, characterized in that: the beam (8) at the joint surface is arranged at the joint surface of the light-duty combined bridge deck with the concrete bridge deck of the reinforced concrete composite beam, an inverted T-shaped stiffening bottom plate (6) is welded below the light-duty steel stiffening plate (4) in the transition structure, a vertical stiffening is additionally arranged below the inverted T-shaped stiffening bottom plate (6), and a concrete slab steel support (7) is formed at the side of the reinforced concrete composite beam; the method comprises the steps that prestressed steel bars (13) are arranged between concrete bridge decks (2), the prestressed steel bars (13) extend to the side of a light combined bridge deck, the prestressed lower stiffening plates (15) are anchored, and a beam (9) at a tensioning end and a beam (16) at an anchoring section are respectively arranged at a prestressed tensioning end and the anchoring section; the connecting part of the cross beam (8) at the joint surface and the concrete bridge deck (2) is provided with a tensile U-shaped rib (11) and a tensile shear pin (12), and the flat section at the tail part of the U-shaped rib (11) is welded with the web plate of the cross beam (8) at the joint surface at both sides.

2. The deck transition construction of claim 1, wherein: the light combined bridge deck comprises an ultra-high performance concrete layer (1), and the thickness of a rigid surface layer below the ultra-high performance concrete layer (1) is smaller than 10cm.

3. The deck transition construction of claim 1, wherein: the steel-concrete composite beam concrete bridge deck is in a composite structure form comprising a steel structure and a concrete panel (2), wherein the concrete panel (2) is a precast slab or a cast-in-situ slab, and the steel structure is an integral box beam, a plurality of box beams, a slab beam and a grid beam.

4. The deck transition construction of claim 1, wherein: the ultra-high performance concrete layer (1) of the light combined bridge deck is extended into the range of 50 cm-100 cm of the steel-concrete combined beam concrete bridge deck.

5. The deck transition construction of claim 1, wherein: the concrete slab steel support (7) below the inverted T-shaped stiffening bottom plate (6) adopts a variable height shape along the force transmission direction.

6. The deck transition construction of claim 1, wherein: the cross beam (10) at the stiffening transition part is provided with a welding hole, and the flat-bulb steel stiffening (4) is continuous in length at the position of the cross beam.

7. The deck transition construction of claim 1, wherein: the length of the flat-bulb steel stiffening plate (4) and the concrete slab steel bearing (7) below the flat-bulb steel stiffening plate and the inverted T-shaped stiffening bottom plate (6) are welded along the force transmission direction by 50 cm-100 cm.

8. The deck transition construction of claim 1, wherein: the distance between the beam (9) at the stretching end of the prestressed reinforcement and the beam (16) at the anchoring end is 300 cm-400 cm.

9. The deck transition construction of claim 2, wherein: the light combined bridge deck is provided with an under-anchor stiffening plate (15), an anchor backing plate (14) is arranged around the under-anchor stiffening plate (15), the under-anchor stiffening plate (15) and the steel top plate (3) form closed stiffening, and the prestressed reinforcement (13) is located inside the closed stiffening structure.

10. The deck transition construction of claim 2, wherein: the prestressed reinforcement (13) is a prestressed steel strand, a thick reinforcement or a parallel steel wire bundle.

11. A bridge deck transition structure method is used for the transition structure of a spherical flat steel stiffening light combined bridge deck and a reinforced concrete combined beam concrete bridge deck, and comprises the following steps:

s1, manufacturing a steel structure part in a factory, wherein the steel structure part comprises a longitudinal and transverse beam structure at two sides, a light combined bridge deck side steel top plate, flat-bulb steel, an inverted T-shaped stiffening web plate and a bottom plate;

s2, applying steel-concrete composite Liang Jianli nails, light composite bridge deck shear nails, tensile shear nails at the joint interfaces, and welding U-shaped steel bars;

s3, constructing a concrete bridge deck plate at the side of the steel-concrete composite beam, wherein when the cast-in-situ bridge deck plate is adopted, a prestressed reinforcement pipeline is buried, and when the prefabricated bridge deck plate is adopted, the prestressed pipeline is reserved according to design files when the bridge deck plate is processed;

s4, maintaining the concrete bridge deck, and tensioning a single end of the prestressed reinforcement at the side of the light combined bridge deck after the strength meets the tensioning condition; grouting a cavity formed by the anchored stiffening plate and the steel top plate after tensioning;

s5, pouring a light combined bridge deck side ultra-high performance concrete layer, and roughening the combination range of the concrete bridge deck plate and the ultra-high performance concrete layer before pouring;

and S6, curing the ultra-high performance concrete layer to finish the construction of the transition structure of the whole light combined bridge deck and the reinforced concrete combined beam concrete bridge deck.