Bridge deck continuous composite structure with beam end crack resistance function

Abstract

The application discloses a bridge deck continuous combination structure with beam end anti-cracking function, which comprises a bridge deck and longitudinal beams, the bridge deck is arranged above the longitudinal beams; the longitudinal beams comprise a plurality of steel beams arranged in sequence along the bridge length direction, and the end of the top surface of the steel beam is provided with a flexible expansion belt; the flexible expansion belt comprises a plurality of strip-shaped openings arranged in sequence and spaced apart on the top surface of the steel beam along the length direction of the steel beam. The application eliminates the cracking disease of the bridge deck; can effectively prevent the corrosion of the steel bars and the steel beams, improves the structural durability; the bridge deck structure has good integrity, large rigidity and strong bearing capacity; the rigidity of the bridge deck is relatively uniform, and the driving smoothness of the bridge deck is better.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge construction, in particular to a bridge deck continuous composite structure with beam end anti-cracking function. BACKGROUND

[0002] The bridge deck continuous composite beam structure is a common bridge structure form, which has the advantages of light structure, large span, good smoothness, reasonable cost, and convenient construction. Since the steel longitudinal beam of the bridge deck continuous composite structure is disconnected at the center line of the pier (the disconnected length is generally 5-8 cm), and the concrete bridge deck is continuous, the end of the steel girder bridge deck is the most weak force bearing position. Under the temperature and vehicle load, the steel girder part will produce a certain horizontal displacement and rotation, and since the length of the steel girder bridge deck is small, it will produce a large longitudinal tensile stress, resulting in cracking of the steel girder bridge deck.

[0003] In order to inhibit the cracking of the bridge deck continuous composite beam structure bridge deck at the steel longitudinal girder part, there are two common treatment methods: 1. The bridge deck structure at the end of the steel longitudinal girder is made of a new material with better tensile performance; 2. Reinforcing the bridge deck structure at the end of the steel longitudinal girder to reduce cracking. For these two schemes, the following shortcomings exist: 1) for scheme 1, on the one hand, it is difficult to find a new material that meets the corresponding requirements, and the connection problem between the new material and ordinary concrete, the construction process, the cost of the new material and other problems need to be solved, and the actual implementation effect is limited; for scheme 2, due to the inherent defect of poor tensile performance of concrete, the bridge deck will still crack after local strengthening of the steel girder bridge deck. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a bridge deck continuous composite structure with beam end anti-cracking function to eliminate the cracking of the bridge deck and effectively prevent the corrosion of the steel bars and the steel girder, improve the durability of the structure, and the bridge deck structure has good integrity, large stiffness and strong bearing capacity, and the bridge deck has better driving smoothness.

[0005] The technical solution adopted by the present application to solve the above technical problems is:

[0006] A bridge deck continuous composite structure with beam end anti-cracking function, comprising a bridge deck and a longitudinal beam, the bridge deck being arranged above the longitudinal beam; the longitudinal beam comprises a plurality of steel girders arranged in sequence along the bridge length direction, and the end of the top surface of the steel girder is provided with a flexible expansion joint;

[0007] The flexible expansion joint comprises a plurality of strip-shaped openings arranged in sequence and spaced apart on the top surface of the steel girder along the length direction of the steel girder.

[0008] According to the above technical solution, the length of the flexible expansion joint is 1000-2000 m.

[0009] According to the technical scheme, the distance d between the two adjacent strip-shaped openings is 100-200 mm.

[0010] According to the technical scheme, the upper width of the strip-shaped opening is narrower than the lower width, the upper width of the strip-shaped opening is 10-20 mm, the lower width is 50-100 mm, and the depth of the strip-shaped opening is 100-200 mm.

[0011] According to the technical scheme, the top surface of the steel beam is provided with a top plate, and the strip-shaped opening is located at the upper part of the steel beam and extends upward to cut off the top plate.

[0012] According to the technical scheme, a thin steel plate is arranged above the strip-shaped opening, and the thin steel plate is arranged between the bridge deck and the steel beam.

[0013] According to the technical scheme, the width of the thin steel plate is 50-100 mm, and the length of the thin steel plate is equal to the width of the top plate of the steel beam.

[0014] According to the technical scheme, a vertical reinforcing rib is arranged between every two adjacent strip-shaped openings, and a vertical reinforcing rib is also arranged outside the strip-shaped opening at the end.

[0015] According to the technical scheme, a plurality of shear nails are inlaid in the lower part of the bridge deck along the bridge length direction in sequence, and the vertical reinforcing rib is arranged directly below the corresponding shear nail.

[0016] According to the technical scheme, a plurality of I-shaped steels are arranged in the steel beam, the web of the I-shaped steel in a region at the end of the steel beam is thickened to form a web thickening area, and a local web stiffening rib is arranged on the web in the web thickening area; the length of the web thickening area is longer than the length of the flexible expansion belt, and the length L of the web thickening area is 1500-2500 mm.

[0017] The present application has the following beneficial effects:

[0018] The present application releases the longitudinal constraint of the steel beam on the bridge deck while retaining the vertical support of the steel beam on the bridge deck, thereby expanding the length of the bridge deck that bears the longitudinal displacement from the traditional inter-beam bridge deck to the inter-beam and both-side flexible belt bridge deck. Since the longitudinal displacement of the steel beam at the end of the service period of the bridge is unchanged, the present application can greatly reduce the tensile stress of the inter-beam bridge deck and eliminate the cracking of the bridge deck after lengthening the length of the tensile zone of the bridge deck. The bridge deck does not crack, the waterproof performance of the structure is good, the corrosion of the steel bars and the steel beam can be effectively prevented, and the durability of the structure is improved. The overall integrity of the bridge deck structure is good, the stiffness of the bridge deck is large, and the carrying capacity is strong. The stiffness of the bridge deck is uniform, and the driving smoothness of the bridge deck is better. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1is a structural schematic view of a bridge deck continuous composite structure with beam end crack resistance function in the embodiment of the present application;

[0020] Figure 2 is a partial K view of Figure 1 ;

[0021] Figure 3 is a structural schematic view of a flexible expansion belt in the embodiment of the present application;

[0022] Figure 4 is a partial M view of Figure 3 ;

[0023] Figure 5 is an a-a sectional view of Figure 3 ;

[0024] In the figure, 1 is a bridge deck slab, 11 is an upper layer of steel mesh, 12 is a lower layer of steel mesh, 2 is a flexible expansion belt, L1 is the length of the flexible expansion belt, 22 is an opening, d is the opening spacing, 222 is a thin steel plate, 23 is a top plate stiffener, 24 is a shear nail, 3 is a steel beam, L is the length of the web thickening area, 32 is the web thickening area, 33 is a general web, and 34 is a local stiffening rib of the web. DETAILED DESCRIPTION

[0025] The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0026] Referring to Figures 1-5 , the present application provides a bridge deck continuous composite structure with beam end crack resistance function in one embodiment, which comprises a bridge deck slab and a longitudinal beam, the bridge deck slab is arranged above the longitudinal beam; the longitudinal beam comprises a plurality of steel beams arranged in sequence along the bridge length direction, a bridge pier is arranged below the butt joint of two adjacent steel beams, and a flexible expansion belt is arranged at the end of the top surface of the steel beam.

[0027] The flexible expansion belt comprises a plurality of strip-shaped openings arranged in sequence and spaced apart on the top surface of the steel beam along the length direction of the steel beam.

[0028] Further, the length of the flexible expansion belt is 1000-2000m.

[0029] Further, the spacing d between two adjacent strip-shaped openings is 100-200mm.

[0030] Further, the upper width of the strip-shaped opening is narrower than the lower width, the upper width of the strip-shaped opening is 10-20mm, the lower width is 50-100mm, and the depth of the strip-shaped opening is 100-200mm.

[0031] Further, the top surface of the steel beam is provided with a top plate, the strip-shaped opening is located at the upper part of the steel beam and extends upward to cut off the top plate of the longitudinal beam, and finally forms an open gap at the upper part.

[0032] Further, a thin steel plate is arranged above the strip-shaped openings, and the thin steel plate is arranged between the concrete of the deck slab and the top plate of the steel beam.

[0033] Further, the width of the thin steel plate is 50-100 mm, and the length of the thin steel plate is equal to the width of the top plate of the steel beam.

[0034] Further, vertical reinforcing ribs are arranged between every two adjacent strip-shaped openings, and vertical reinforcing ribs are also arranged outside the strip-shaped openings at the end.

[0035] Further, a plurality of shear studs are embedded in the lower part of the deck slab along the length direction of the bridge in sequence and in intervals, and the vertical reinforcing ribs are arranged directly below the corresponding shear studs.

[0036] Further, a plurality of I-shaped steel are arranged in the steel beam, the web of the I-shaped steel in a region at the end of the steel beam is thickened to form a web thickening area, and a local web stiffening rib is arranged on the web of the I-shaped steel in the web thickening area; the length of the web thickening area is longer than the length of the flexible expansion belt, and the length L of the web thickening area is 1500-2500 mm.

[0037] Further, the deck slab comprises a reinforced concrete surface layer, which is a double-layer double-direction reinforced concrete slab structure, wherein the steel mesh is arranged along the top and bottom surfaces of the concrete slab respectively, the reinforced concrete surface layer comprises a concrete slab, and upper and lower steel meshes arranged at the upper and lower parts of the concrete slab, and the shear stud is arranged at the lower steel mesh.

[0038] The working principle of the present application is as follows: the main structural components of the present application are as shown in Figure 1 and Figure 2 , which mainly comprise: a deck slab 1, a steel beam 3, and a flexible expansion belt 2 arranged on the steel beam:

[0039] As shown in Figure 3 , which is a partial structural schematic diagram of the structure, wherein the top and bottom plates of the deck slab are both provided with upper and lower steel meshes 11 and 12.

[0040] According to the above scheme, the length L1 of the flexible expansion belt is 1000-2000 mm.

[0041] According to the above scheme, the flexible expansion belt 2 is realized by arranging a series of strip-shaped openings 22 on the steel beam.

[0042] Further, the strip-shaped openings 22 have a distribution opening spacing d of 100-200 mm, the openings are long strips with a narrow upper part and a wide lower part, and the widened and cornered parts adopt a circular arc transition.

[0043] Furthermore, the strip-shaped opening 22 has a width of 10-20mm at the narrower part at the top, a width of 50-100mm at the wider part at the bottom, and an overall height of 100-200mm.

[0044] Furthermore, the strip-shaped opening 22 is located on the upper part of the steel beam and extends upward to cut off the top plate of the longitudinal beam, ultimately forming an upper open notch.

[0045] Furthermore, the opening 22 has a thin steel plate 222 with a width of 50-100mm at the interface between the opening of the longitudinal beam top plate and the concrete. The length of the thin steel plate is equal to the width of the steel beam top plate to prevent concrete from flowing out along the cut joint of the I-beam top plate during construction.

[0046] Furthermore, the flexible telescopic belt 2 is provided with vertical reinforcing ribs 23 at the bottom of each section of the top plate;

[0047] Furthermore, the vertical stiffening rib 23 is aligned with the shear stud 24 on the upper part of the I-beam;

[0048] Furthermore, the I-beam 3, in order to enhance the shear resistance of the steel beam at the support, has a web plate thickening reinforcement zone in a certain area at the end of the steel beam, namely the web plate thickening zone 32.

[0049] Furthermore, the length L of the web thickening zone of the I-beam 3 is 1500-2500 mm;

[0050] In summary, continuous composite beam structures, as a common bridge structural form, offer advantages such as lightweight construction, large span, good ride comfort, reasonable cost, and convenient construction. However, because continuous composite beam structures consist of simply supported steel beams with a continuous deck, they are highly susceptible to cracking at the break points in the main beams during bridge service due to temperature and load effects. The innovation of this invention lies in designing cuts in the top plate and web of the steel main beam ends within a certain range, forming a flexible expansion band at the top of the beam ends. This expands the length of the bridge deck bearing longitudinal loads, reducing or even eliminating cracking of the bridge deck between beams.

[0051] In summary, the inter-beam bridge deck is free from cracking: the present application forms a flexible expansion belt at the end of the steel beam by cutting the top plate and web within a certain range of the end of the steel beam, which releases the longitudinal constraint of the steel beam on the bridge deck while retaining the vertical support of the steel beam on the bridge deck, thereby expanding the length of the bridge deck that bears longitudinal displacement from the traditional inter-beam bridge deck (length: b = 5-8 cm, b is also the spacing length between the ends of two adjacent steel beams) to the inter-beam and two-side flexible belt bridge deck (length: b+2L1 = 200-400 cm); since the longitudinal displacement of the steel beam at the end of the service period of the bridge does not change, the present application can greatly reduce the tensile stress of the inter-beam bridge deck after lengthening the length of the tensile zone of the bridge deck, and eliminate the cracking of the bridge deck; strong waterproof ability and good structural durability: after using the present application, the bridge deck does not crack, the structure has good waterproof performance, can effectively prevent the corrosion of steel bars and steel beams, and improve the structural durability; large structural stiffness and strong bearing capacity: for the present application, since the bridge deck is basically free from cracking, the bridge deck structure has good integrity, large bridge deck stiffness and strong bearing capacity; the bridge deck is smoother: after using the new structure, the inter-beam bridge deck does not crack, the bridge deck stiffness is more uniform, and the bridge deck is smoother.

[0052] The above is only a preferred embodiment of the present application, of course, cannot limit the scope of the patent rights of the present application, therefore, the equivalent changes made in the scope of the patent application of the present application, still belongs to the protection scope of the present application.

Claims

1. A continuous composite bridge deck structure with beam end crack resistance, characterized in that, The bridge deck and the longitudinal beam, the bridge deck is arranged above the longitudinal beam; the longitudinal beam comprises a plurality of steel beams arranged in sequence along the bridge length direction, and the end of the top surface of the steel beam is provided with a flexible expansion belt; The flexible expansion belt comprises a plurality of strip-shaped openings arranged in sequence and spaced apart on the top surface of the steel beam along the length direction of the steel beam; The length of the flexible expansion belt is 1000-2000m; The distance d between the two adjacent strip-shaped openings is 100-200mm; The upper width of the strip-shaped opening is narrower than the lower width, the upper width of the strip-shaped opening is 10-20mm, the lower width is 50-100mm, and the depth of the strip-shaped opening is 100-200mm; The top surface of the steel beam is provided with a top plate, the strip-shaped opening is located on the upper part of the steel beam and extends upward to cut off the top plate; A thin steel plate is arranged above the strip-shaped opening, and the thin steel plate is arranged between the bridge deck and the steel beam; The width of the thin steel plate is 50-100mm, and the length of the thin steel plate is equal to the width of the top plate of the steel beam; Vertical reinforcing ribs are arranged between every two adjacent strip-shaped openings, and the outer side of the strip-shaped opening at the end is also provided with a vertical reinforcing rib; A plurality of shear nails are inlaid in sequence and spaced apart in the lower part of the bridge deck along the bridge length direction, and the vertical reinforcing rib is arranged directly below the corresponding shear nail; A plurality of I-shaped steel are arranged in the steel beam, the web of the I-shaped steel in the end region of the steel beam is thickened to form a web thickening area, and a local web stiffening rib is arranged on the web in the web thickening area; the length of the web thickening area is longer than the length of the flexible expansion belt, and the length L of the web thickening area is 1500-2500mm.

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