New and old bridge widening structure

Abstract

The utility model discloses a widening structure for a new bridge and an old bridge. The widening structure comprises an old bridge T beam, a new bridge T beam and a plurality of anchoring steel bars, an old cantilever arm of the old bridge T beam is provided with a chiseling flange surface and a plurality of straightening old bridge steel bars; a plurality of first transverse steel bars are arranged on a new cantilever arm of the new bridge T beam; each anchoring steel bar comprises an anchoring section and a connecting section which are connected in sequence; the anchoring section is inserted into an old cantilever of the old bridge T beam, and the connecting section, the first transverse reinforcing steel bar and the straightening old bridge reinforcing steel bar are sequentially in lap joint from top to bottom and are connected through welding; splicing structure concrete is arranged between the chiseling flange face and a new cantilever of the new bridge T beam, the splicing structure concrete is made of fiber reinforced cement-based composite materials, and the connecting section is embedded in the splicing structure concrete. According to the structure, the cracking degree of the structure between the new bridge and the old bridge can be reduced, the anti-permeability of the structure after cracking can be improved, and the connection strength and the loading capacity are high.

Description

Technical Field

[0001] The utility model relates to the field of bridge engineering, in particular to a new and old bridge widening structure. Background Art

[0002] With the rapid development of my country's economy and society, a large number of expressways have been built. In order to facilitate traffic transfer between new and old expressways, hubs are set up between new expressways and existing expressways to achieve traffic transfer, resulting in a large number of road widening projects. However, in road widening construction, there has been no better solution for the research on construction technology to prevent cracking of the widening structure of new and old bridges and the connection processing technology of new and old roads. Especially in bridge widening construction, the problem is more prominent. During the operation of the widened bridge, a certain degree of cracks appeared in the widening structure of the new and old bridges, thereby affecting the durability of the concrete structure.

[0003] The existing structure of widening the old and new bridges has the following disadvantages: (1) The difference in shrinkage, creep, and settlement between the new and old bridges causes varying degrees of cracking in the concrete of the widening joint. (2) After the T-beam and small box girder are widened, they change from side beams to center beams, making the installation of a new transverse diaphragm between the new and old bridges extremely troublesome and complicated. Utility Model Content

[0004] In view of this, the purpose of the present invention is to provide a new and old bridge widening structure, which can reduce the degree of structural cracking between the new and old bridges, improve its anti-seepage property after cracking, and has high connection strength and load capacity.

[0005] The utility model discloses a new and old bridge widening structure, comprising an old bridge T-beam, a new bridge T-beam and a plurality of anchoring steel bars; the old cantilever of the old bridge T-beam is provided with a roughened flange surface and a plurality of straightened old bridge steel bars on the side facing the new bridge T-beam; the plurality of straightened old bridge steel bars are arranged at intervals along the length direction of the bridge, and the plurality of straightened old bridge steel bars all protrude from the roughened flange surface; the new cantilever of the new bridge T-beam is provided with a plurality of first transverse steel bars on the side facing the old bridge T-beam;

[0006] The plurality of anchoring steel bars each include an anchoring section and a connecting section connected in sequence; the anchoring section is inserted into the old cantilever of the old bridge T-beam, and the connecting section, the first transverse steel bar and the straightened old bridge steel bar are overlapped in sequence from top to bottom and connected by welding;

[0007] A splicing structural concrete is provided between the roughened flange surface and the new cantilever arm of the new bridge T-beam. The splicing structural concrete is made of fiber-reinforced cement-based composite material, and the connecting section is embedded in the splicing structural concrete.

[0008] Furthermore, a plurality of first steel wires for binding are provided at intervals on the periphery of the connecting section, the first transverse steel bar and the straightened old bridge steel bar.

[0009] Furthermore, it also includes a reinforcing longitudinal steel bar, which is located above the connecting section. The reinforcing longitudinal steel bar and the connecting section are perpendicular to each other, and the intersection of the two is connected by welding.

[0010] Furthermore, the new bridge T-beam also includes a plurality of first longitudinal steel bars arranged at intervals along the width direction of the bridge, the first longitudinal steel bars are located above the first transverse steel bars, the plurality of first transverse steel bars and the plurality of first longitudinal steel bars are crisscrossed to form a first steel mesh, and the intersection of the two is tied by a second steel wire.

[0011] Furthermore, a paving groove is provided on the upper side of the T-beam of the old bridge, and a second steel mesh is provided on the T-beam of the new bridge, and the second steel mesh extends above the splicing structure concrete and into the paving groove.

[0012] Furthermore, a concrete pavement layer is provided on the T-beam of the new bridge, and the concrete pavement layer extends above the splicing structure concrete and into the paving groove.

[0013] Furthermore, the material of the concrete pavement layer is fiber-reinforced cement-based composite material.

[0014] Furthermore, the second steel mesh is embedded in the concrete pavement layer; the second steel mesh includes a plurality of second transverse steel bars arranged at intervals along the length direction of the bridge and a plurality of second longitudinal steel bars arranged at intervals along the width direction of the bridge. The plurality of second transverse steel bars and the plurality of second longitudinal steel bars are crisscrossed to form a mesh structure, and the intersection of the two is tied by a third steel wire.

[0015] Furthermore, a waterproof layer is provided on the concrete pavement layer of the T-beam of the new bridge, and the waterproof layer extends above the splicing structure concrete and into the paving groove.

[0016] Furthermore, an asphalt pavement layer is provided on the waterproof layer of the T-beam of the new bridge, and the asphalt pavement layer extends above the splicing structure concrete and into the paving groove.

[0017] The beneficial effects of the utility model are:

[0018] (1) The material of the spliced ​​structural concrete of the utility model adopts fiber-reinforced cement-based composite material, which can reduce the degree of structural cracking between the new and old bridges and improve the anti-permeability after cracking.

[0019] (2) The anchoring section of the anchoring steel bar of the utility model can transfer the load to the concrete of the old cantilever arm. The connecting section, the first transverse steel bar and the straightened old bridge steel bar are overlapped in sequence from top to bottom and connected by welding to form a whole, forming a through load transfer path. After being embedded in the spliced ​​structure concrete, it can ensure the load capacity of the spliced ​​structure of the new and old bridges.

[0020] (3) The present invention can ensure the connection strength of the old bridge T-beam, the spliced ​​structural concrete and the new bridge T-beam by designing anchor steel bars, the first transverse steel bars, the straightened old bridge steel bars, the fiber-reinforced cement-based composite materials and the roughened flange surface, thereby eliminating the need for structures such as transverse diaphragms and stiffening plates during traditional widening.

[0021] (4) The utility model can facilitate the transmission of local forces to the entire structural system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention is described with the following drawings:

[0023] Figure 1 It is a structural diagram of the utility model;

[0024] Figure 2 for Figure 1 A partial enlarged schematic diagram of the structure nearby corresponding to the spliced ​​structural concrete.

[0025] The following are marked in the accompanying drawings:

[0026] 1- T-beam of old bridge, 101- old cantilever, 102- roughening flange surface, 103- straightening steel bars of old bridge, 104- paving trough;

[0027] 2-new bridge T-beam, 201-new cantilever, 202-first steel mesh, 2021-first transverse steel bar, 2022-first longitudinal steel bar, 2023-second steel wire;

[0028] 3-anchor steel bar, 301-anchor section, 302-connecting section;

[0029] 4-spliced ​​structural concrete, 5-first steel wire, 6-reinforced longitudinal steel bars;

[0030] 7-second steel mesh, 701-second transverse steel bar, 702-second longitudinal steel bar, 703-third steel wire;

[0031] 8-concrete pavement layer, 9-waterproof layer, 10-asphalt pavement layer. DETAILED DESCRIPTION

[0032] The technical solution of the present utility model is described in detail below with reference to the accompanying drawings and embodiments.

[0033] like Figure 1 and Figure 2 As shown, in this embodiment, a new and old bridge widening structure comprises an old bridge T-beam 1, a new bridge T-beam 2 and a plurality of anchoring steel bars 3; the old cantilever 101 of the old bridge T-beam 1 is provided with a roughened flange surface 102 and a plurality of straightened old bridge steel bars 103 on the side facing the new bridge T-beam 2; the plurality of straightened old bridge steel bars 103 are arranged at intervals along the length direction of the bridge, and the plurality of straightened old bridge steel bars 103 all protrude from the roughened flange surface 102; the new cantilever 201 of the new bridge T-beam 2 is provided with a plurality of first transverse steel bars arranged at intervals along the length direction of the bridge. Rebar 2021; the plurality of anchoring steel bars 3 each include an anchoring section 301 and a connecting section 302 connected in sequence; the anchoring section 301 is inserted into the old cantilever 101 of the old bridge T-beam 1, and the connecting section 302, the first transverse steel bar 2021 and the straightened old bridge steel bar 103 are overlapped in sequence from top to bottom and connected by welding; a splicing structural concrete 4 is provided between the roughened flange surface 102 and the new cantilever 201 of the new bridge T-beam 2, and the material of the splicing structural concrete 4 is fiber-reinforced cement-based composite material, and the connecting section 302 is embedded in the splicing structural concrete 4.

[0034] Fiber-reinforced cementitious composites refer to ECC (Engingeered Cementitious Composites) concrete. ECC concrete is a highly ductile fiber-reinforced cementitious composite material with excellent physical and mechanical properties as well as safety, durability, and applicability. The spliced ​​structural concrete 4 is made of fiber-reinforced cementitious composites, which can reduce the degree of structural cracking between new and old bridges and improve its impermeability after cracking.

[0035] The anchoring section 301 of the anchoring steel bar 3 can transfer the load to the concrete of the old cantilever 101. A reserved gap is set between the connecting section 302 and the straightened old bridge steel bar 103. The connecting section 302, the first transverse steel bar 2021 and the straightened old bridge steel bar 103 are overlapped in sequence from top to bottom and connected by welding to form a whole, forming a through load transfer path, which can be embedded in the splicing structure concrete 4 to ensure the load capacity of the spliced ​​structure of the new and old bridges.

[0036] In addition, by designing the anchor steel bars 3, the first transverse steel bars 2021, the straightened old bridge steel bars 103, the fiber-reinforced cement-based composite materials and the roughened flange surface 102, the connection strength of the old bridge T-beam 1, the spliced ​​structural concrete 4 and the new bridge T-beam 2 can be ensured, eliminating the structures such as the transverse partitions and stiffening plates used in traditional widening.

[0037] The straightened old bridge rebar 103 is obtained by chiseling away the concrete at the edge of the old cantilever arm 101 of the old bridge T-beam 1, facing the new bridge T-beam 2, with a chiseling width of 25-40 cm, preferably 30 cm. After the concrete is removed, the internal rebar of the old cantilever arm 101 is exposed. The exposed rebar is retained and straightened to form the straightened old bridge rebar 103.

[0038] In this embodiment, multiple first steel wires 5 are spaced apart around the periphery of the connecting section 302, the first transverse reinforcement 2021, and the straightened old bridge reinforcement 103 for binding. The lengths of the connecting section 302, the first transverse reinforcement 2021, and the straightened old bridge reinforcement 103 all run along the width of the bridge, and the welds formed at the overlaps also run along the width of the bridge. Binding the connecting section 302, the first transverse reinforcement 2021, and the straightened old bridge reinforcement 103 together with the first steel wires 5 further increases the strength of the connection and improves the longitudinal load capacity. The first steel wires 5, in conjunction with the welds, prevent the three from separating.

[0039] This embodiment also includes reinforcing longitudinal reinforcement bars 6 positioned above the connecting section 302. The reinforcing longitudinal reinforcement bars 6 are perpendicular to the connecting section 302, and the two are welded at their intersection. The reinforcing longitudinal reinforcement bars 6 extend along the length of the bridge and are perpendicular to the connecting section 302. This connects the connecting sections 302 together, facilitating the transfer of local forces to the anchor bars 3, the straightened old bridge bars 103, and the first transverse reinforcement bars 2021, thereby facilitating the transfer of forces to the entire structural system.

[0040] In this embodiment, the new bridge T-beam 2 further includes a plurality of first longitudinal steel bars 2022 spaced apart along the width of the bridge. The first longitudinal steel bars 2022 are positioned above the first transverse steel bars 2021. The plurality of first transverse steel bars 2021 and the plurality of first longitudinal steel bars 2022 are crisscrossed to form a first steel mesh 202 with a mesh structure. The intersections of the first transverse steel bars 2021 and the first longitudinal steel bars 2022 are bound together by second steel wires 2023. The crisscrossing of the plurality of first transverse steel bars 2021 and the plurality of first longitudinal steel bars 2022 to form a mesh structure can enhance the load-bearing capacity of the first steel mesh 202 and facilitate the transmission of local forces to the entire structural system.

[0041] In this embodiment, a paving groove 104 is provided on the upper side of the old bridge T-beam 1, and a second steel mesh 7 is provided on the new bridge T-beam 2, and the second steel mesh 7 extends above the spliced ​​structural concrete 4 and into the paving groove 104.

[0042] The source of the paving groove 104 is: when the concrete at the edge of the old cantilever 101 facing the new bridge T-beam 2 is chiseled out, the paved bridge deck on the upper surface of the old bridge T-beam 1 is chiseled out at the same time, forming the paving groove 104. The paving groove 104 extends from the middle of the bridge to the edge of the old cantilever 101.

[0043] In this embodiment, a concrete pavement layer 8 is provided on the new bridge T-beam 2 , and the concrete pavement layer 8 extends above the splicing structure concrete 4 and into the paving groove 104 .

[0044] In this embodiment, the material of the concrete pavement layer 8 is fiber-reinforced cementitious composite material, and the fiber-reinforced cementitious composite material refers to ECC (Engingeered Cementitious Composites) concrete.

[0045] In this embodiment, the second steel mesh 7 is embedded in the concrete pavement layer 8; the second steel mesh 7 includes a plurality of second transverse steel bars 701 spaced apart along the length direction of the bridge and a plurality of second longitudinal steel bars 702 spaced apart along the width direction of the bridge. The plurality of second transverse steel bars 701 and the plurality of second longitudinal steel bars 702 are crisscrossed to form a mesh structure, and the intersection of the two is tied together by a third steel wire 703.

[0046] In this embodiment, a waterproof layer 9 is provided on the concrete pavement layer 8 of the new bridge T-beam 2 , and the waterproof layer 9 extends above the splicing structure concrete 4 and into the paving groove 104 .

[0047] In this embodiment, an asphalt pavement layer 10 is provided on the waterproof layer 9 of the new bridge T-beam 2 , and the asphalt pavement layer 10 extends above the splicing structure concrete 4 and into the paving groove 104 .

[0048] The concrete pavement layer 8 and the second steel mesh 7 enhance the structural strength of the bridge deck. The concrete pavement layer 8 is made of the same material as the spliced ​​structural concrete 4. The ECC concrete reduces the extent of structural cracking in the concrete pavement layer 8 and improves its impermeability after cracking. The waterproof layer 9, located above the concrete pavement layer 8, prevents moisture from penetrating into the concrete pavement layer 8, further enhancing its impermeability. The asphalt pavement layer 10 exhibits excellent compressive, shear, and fatigue resistance, capable of withstanding repeated vehicle loads and extending the service life of the bridge surface.

[0049] During construction, the following steps are included:

[0050] S1. Remove the concrete from the edge of the old cantilever 101 of the old bridge T-beam 1 on the side facing the new bridge T-beam 2. The removal width is 25-40 cm, preferably 30 cm. Then, remove the paved bridge surface on the upper surface of the old bridge T-beam 1 to form a paving groove 104. The removal depth is 10-25 cm, preferably 15 cm.

[0051] After the concrete is removed, the internal steel bars of the old cantilever arm 101 are exposed. The exposed steel bars are retained and straightened to become the straightened old bridge steel bars 103. At the same time, after the concrete is removed, the edges of the old cantilever arm 101 are roughened to create a roughened flange surface 102. This roughened flange surface 102 serves as an anchoring surface for the anchor section 301 and improves the bond between the new and old concrete, enhancing the stability and durability of the structure.

[0052] It is worth noting that, during the roughening process, if there are local defects on the roughened flange surface 102, it should be reinforced or strengthened before proceeding to step S2.

[0053] S2. Use mechanical equipment to first drill matching threaded holes in the corresponding positions of the concrete of the old cantilever arm 101. Then, insert the anchoring section 301 of the anchoring steel bar 3 into the old cantilever arm 101 of the old bridge T through the anchoring surface. The anchoring section 301 is screwed into the hole. The cutting teeth of the anchoring section 301 cut into the concrete and mechanically engage with the concrete, thereby transferring the load to the concrete of the old cantilever arm 101. The drilling position should avoid the internal steel bars of the old cantilever arm 101. In this embodiment, the drilling position is located above the straightened old bridge steel bar 103, so that a reserved gap is set between the connecting section 302 and the straightened old bridge steel bar 103. The reserved gap can ensure that it is staggered with the position of the internal steel bars of the old cantilever arm 101, and the reserved gap can be used for the subsequent insertion of the first transverse steel bar 2021.

[0054] S3. During the construction of the new bridge T-beam 2, the first steel mesh 202 is preset. During the preset process, the first transverse reinforcement 2021 is inserted into the reserved gap, and the connecting section 302, the first transverse reinforcement 2021 and the straightened old bridge reinforcement 103 are overlapped from top to bottom and connected by welding to form a whole. Subsequently, the first longitudinal reinforcement 2022 is placed at intervals above the first transverse reinforcement 2021. Multiple first transverse reinforcements 2021 and multiple first longitudinal reinforcements 2022 are crisscrossed and tied together by the second steel wire 2023 to form the first steel mesh 202. Next, the reinforced longitudinal reinforcement 6 is welded to the connecting section 302. Finally, the connecting section 302, the first transverse reinforcement 2021 and the straightened old bridge reinforcement 103 are tied together by the first steel wire 5.

[0055] S4. Pour the spliced ​​structural concrete 4. From the start of pouring until it reaches the required design strength, the old bridge T-beam 1 is closed to traffic or only the lane away from the new bridge T-beam 2 is open to traffic. During this period, the old bridge T-beam 1 and the new bridge T-beam 2 need to be temporarily connected using steel sections to ensure that the vertical deflections of the old bridge T-beam 1 and the new bridge T-beam 2 are coordinated and consistent, thereby ensuring the quality of the spliced ​​structural concrete 4.

[0056] S5. After the main structure of the new bridge T-beam 2 is completed, the second steel mesh 7, the concrete pavement layer 8, the waterproof layer 9 and the asphalt pavement layer 10 are pre-set in different time periods.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model and are not limiting. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A new and old bridge widening structure, characterized by: The invention comprises an old bridge T-beam (1), a new bridge T-beam (2), and a plurality of anchoring steel bars (3); a side of an old cantilever arm (101) of the old bridge T-beam (1) facing the new bridge T-beam (2) is provided with a roughened flange surface (102) and a plurality of straightened old bridge steel bars (103); the plurality of straightened old bridge steel bars (103) are arranged at intervals along the length direction of the bridge, and the plurality of straightened old bridge steel bars (103) all protrude from the roughened flange surface (102); a side of a new cantilever arm (201) of the new bridge T-beam (2) facing the old bridge T-beam (1) is provided with a plurality of first transverse steel bars (2021); the plurality of anchoring steel bars (3) Each comprises an anchoring section (301) and a connecting section (302) connected in sequence; the anchoring section (301) is inserted into the old cantilever (101) of the old bridge T-beam (1); the connecting section (302), the first transverse reinforcement (2021) and the straightened old bridge reinforcement (103) are overlapped in sequence from top to bottom and connected by welding; a splicing structural concrete (4) is provided between the roughened flange surface (102) and the new cantilever (201) of the new bridge T-beam (2); the splicing structural concrete (4) is made of a fiber-reinforced cement-based composite material, and the connecting section (302) is embedded in the splicing structural concrete (4).

2. The new and old bridge widening structure according to claim 1 is characterized in that: A plurality of first steel wires (5) for binding are provided at intervals on the periphery of the connecting section (302), the first transverse steel bar (2021), and the straightened old bridge steel bar (103).

3. The new and old bridge widening structure according to claim 1 is characterized in that: It also includes a reinforcing longitudinal steel bar (6), the reinforcing longitudinal steel bar (6) is located above the connecting section (302), the reinforcing longitudinal steel bar (6) and the connecting section (302) are perpendicular to each other, and the intersection of the two is connected by welding.

4. The new and old bridge widening structure according to claim 1 is characterized in that: The new bridge T-beam (2) further comprises a plurality of first longitudinal steel bars (2022) spaced apart along the width direction of the bridge, wherein the first longitudinal steel bars (2022) are located above the first transverse steel bars (2021), the plurality of first transverse steel bars (2021) and the plurality of first longitudinal steel bars (2022) are crisscrossed to form a first steel mesh (202), and the intersections of the two are tied together by second steel wires (223).

5. The new and old bridge widening structure according to claim 1 is characterized in that: A paving groove (104) is provided on the upper side of the old bridge T-beam (1), a second steel mesh (7) is provided on the new bridge T-beam (2), and the second steel mesh (7) extends above the spliced ​​structural concrete (4) and into the paving groove (104).

6. The new and old bridge widening structure according to claim 5 is characterized in that: A concrete pavement layer (8) is provided on the new bridge T-beam (2), and the concrete pavement layer (8) extends above the spliced ​​structural concrete (4) and into the pavement groove (104).

7. The new and old bridge widening structure according to claim 6 is characterized in that: The material of the concrete pavement layer (8) is a fiber-reinforced cement-based composite material.

8. The new and old bridge widening structure according to claim 6 is characterized in that: The second steel mesh (7) is embedded in the concrete pavement layer (8); the second steel mesh (7) comprises a plurality of second transverse steel bars (701) spaced apart along the length direction of the bridge and a plurality of second longitudinal steel bars (702) spaced apart along the width direction of the bridge, the plurality of second transverse steel bars (701) and the plurality of second longitudinal steel bars (702) being crisscrossed to form a mesh structure, and the intersections of the two are tied together by a third steel wire (703).

9. The new and old bridge widening structure according to claim 6 is characterized in that: A waterproof layer (9) is provided on the concrete pavement layer (8) of the new bridge T-beam (2), and the waterproof layer (9) extends above the spliced ​​structural concrete (4) and into the pavement groove (104).

10. The new and old bridge widening structure according to claim 9 is characterized in that: An asphalt pavement layer (10) is provided on the waterproof layer (9) of the new bridge T-beam (2), and the asphalt pavement layer (10) extends above the spliced ​​structural concrete (4) and into the paving groove (104).

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