Transverse reinforcement system and construction method of existing hollow slab girder bridge

Abstract

The present invention discloses a transverse reinforcement system for an existing hollow slab beam bridge and a construction method thereof. The system includes transverse reinforcement units distributed longitudinally along the hollow slab beam body. The transverse reinforcement units include a prestressed steel structure installed on the bottom side of the hollow slab by bolts and a connecting steel structure installed on the outside of the web of the hollow slab side plate by bolts. The prestressed steel structure is arranged transversely and its main body is an I-beam or box-section steel. The prestressed steel structure is pre-set with a prestressed steel bundle and its installation assembly before installation. After installation, the prestressed steel bundle is tensioned and fixed. The prestressed steel bundle extends from near one end of the prestressed steel structure to near the other end. The connecting steel structure is located at both ends of the prestressed steel structure. The bottom end of the connecting steel structure is bolted or welded to the end of the prestressed steel structure, and a stiffening plate is provided in the connection area between the two. The present invention improves the safety and durability of existing hollow slab beam bridges, has low construction difficulty, and has a small increase in deadweight.

Description

Technical Field

[0001] The present invention belongs to the field of bridge construction, and in particular relates to a transverse reinforcement system for an existing hollow slab beam bridge and a construction method thereof. Background Art

[0002] Prefabricated hollow slabs currently represent a significant portion of the existing stock on highways and municipal roads due to their ease of construction, high efficiency, and low cost. Previous designs of hollow slab beam bridges focused excessively on economic indicators, neglecting structural details and resistance reserves. This resulted in poor structural durability and widespread transverse defects such as support voids, hinged joint failures, and single-slab stress. These posed significant safety risks and are no longer recommended within the industry or in most regions. To avoid these issues, existing hollow slabs require transverse reinforcement. However, current reinforcement methods require pouring concrete at the base of the slab, which is not only inefficient and difficult to construct, but also significantly increases the deadweight of the existing structure, creating new challenges. Summary of the Invention

[0003] The purpose of the present invention is to provide a transverse reinforcement system for an existing hollow slab beam bridge and a construction method thereof. The present invention improves the safety and durability of the existing hollow slab beam bridge, has low construction difficulty, and has a small increase in deadweight.

[0004] The technical solution adopted in the present invention is:

[0005] A transverse reinforcement system for an existing hollow slab beam bridge comprises transverse reinforcement units distributed longitudinally along the hollow slab beam body, the transverse reinforcement units comprising a prestressed steel structure installed on the underside of the hollow slab by means of bolts and a connecting steel structure installed on the outside of the web of the side plate of the hollow slab by means of bolts; the prestressed steel structure is arranged transversely and its main body is an I-beam or box-section steel; the prestressed steel structure is preset with prestressed steel bundles and their installation components inside before installation; the prestressed steel bundles are tensioned and fixed after installation, and the prestressed steel bundles extend from near one end of the prestressed steel structure to near the other end; the connecting steel structures are located at both ends of the prestressed steel structure, the bottom end of the connecting steel structure is bolted or welded to the end of the prestressed steel structure, and a stiffening plate is provided in the connection area between the two.

[0006] Preferably, bolt pads are provided at the bolt installation positions of the prestressed steel structure and the connecting steel structure.

[0007] Preferably, the prestressed steel strands are in a straight line parallel to the bottom of the hollow slab, a broken line with high ends and low middle, or a curved line with high ends and low middle.

[0008] Preferably, the prestressed steel strand adopts a tensioning method in which one end is anchored and the other end is tensioned, or a tensioning method in which both ends are tensioned.

[0009] Preferably, the installation components of the prestressed steel tendon include one or more of an anchoring node, a turning node, and a tensioning node.

[0010] Preferably, the main body of the connecting steel structure is an I-beam.

[0011] The construction method of the above-mentioned transverse reinforcement system of the existing hollow slab girder bridge is: comprising the steps of: 1) repairing and reinforcing the existing hollow slab girder bridge that has developed transverse defects; 2) based on the mechanical analysis of the existing hollow slab girder bridge, combined with on-site inspection and testing, obtaining the cross-sectional deformation curves at different positions of the existing hollow slab girder bridge, and considering the convenience of construction, determining the number and position of the transverse reinforcement units, determining the number, line type, tensioning method and tensioning control force of the prestressed steel bundles in each prestressed steel structure, and determining the main body of the prestressed steel structure according to the position of the prestressed steel structure. Whether to use I-beams or box-section steel; 3) Install corresponding prestressed steel bundles and their installation components inside each prestressed steel structure, install connecting steel structures at both ends of the prestressed steel structure and set stiffening plates in the connection area to form each transverse reinforcement unit; 4) Install each transverse reinforcement unit at the corresponding longitudinal position of the hollow slab beam, wherein the prestressed steel structure and the connecting steel structure are respectively installed on the lower side of the hollow slab bottom and the outer side of the outer web of the hollow slab side plate by bolts; 5) Tension and fix the corresponding prestressed steel bundles according to the determined tensioning method and tensioning control force to protect the prestressed steel bundles.

[0012] Preferably, in step 1), the repair and reinforcement treatment includes peeling and cleaning the hinge joints, re-pouring the hinge joints, and repairing the bridge deck pavement.

[0013] Preferably, in step 2), when the location of the prestressed steel structure requires frequent inspection, maintenance or replacement of prestressed steel strands, the main body of the prestressed steel structure adopts I-beams; when the location of the prestressed steel structure requires ensuring the safety of the prestressed steel strands, the main body of the prestressed steel structure adopts box-section steel.

[0014] Preferably, in step 5), when the prestressed steel strands are tensioned, displacement detection is performed on each hollow slab during the tensioning process to ensure the overall safety of the existing hollow slab beam bridge; and the tensioning task is performed symmetrically from the mid-span to both ends.

[0015] The beneficial effects of the present invention are:

[0016] The present invention combines steel structure and prestressing to transversely reinforce the existing hollow slab beam bridge, and bears stress as a whole with the existing hollow slab beam bridge, which can promote the coordination of structural stress and deformation, greatly enhance the transverse integrity and load-bearing performance of the existing hollow slab beam bridge, and effectively improve the fatigue performance of the steel structure. Moreover, the steel structure is arranged at the lower edge and mainly bears tensile stress, which conforms to the material properties. In short, the safety and durability of the existing hollow slab beam bridge are improved. Compared with conventional transverse reinforcement, the present invention mainly adopts steel structure components, avoids formwork, brackets and maintenance processes, and has no redundant materials, which can greatly improve work efficiency and reduce construction difficulty. Moreover, the increase in the deadweight of the existing hollow slab beam bridge is small, which is beneficial to the safety of the structure itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view of a certain part of the transverse reinforcement system of an existing hollow slab girder bridge in an embodiment of the present invention.

[0018] Figure 2 It is a diagram of a prestressed steel structure somewhere in an embodiment of the present invention.

[0019] Figure 3 It is a longitudinal section view of a certain section of the transverse reinforcement system of an existing hollow slab girder bridge in an embodiment of the present invention.

[0020] Figure 4 yes Figure 3 Enlarged view of point A in the middle.

[0021] Figure 5 yes Figure 3 Enlarged view of point B in the middle.

[0022] In the figure: 1- bottom of hollow slab; 2- I-beam; 3- outer web of hollow slab side plate; 4- prestressed steel structure; 5- box section steel; 6- prestressed steel tendon; 7- tensioning node; 8- anchor node; 9- turning node; 10- connection steel structure; 11- bolt; 12- bolt pad; 13- stiffening plate. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings and examples.

[0024] like Figures 1 to 5As shown, a transverse reinforcement system for an existing hollow slab beam bridge includes transverse reinforcement units distributed longitudinally along the hollow slab beam body, the transverse reinforcement units including a prestressed steel structure 4 installed on the lower side of the hollow slab bottom 1 by bolts 11 and a connecting steel structure 10 installed on the outer side of the outer web 3 of the hollow slab side plate by bolts 11; the prestressed steel structure 4 is arranged transversely and the main body is an I-beam 2 or a box-section steel 5, the prestressed steel structure 4 is preset with a prestressed steel bundle 6 and its installation assembly before installation, and the prestressed steel bundle 6 is tensioned and fixed after installation, and the prestressed steel bundle 6 extends from near one end of the prestressed steel structure 4 to near the other end; the connecting steel structure 10 is located at both ends of the prestressed steel structure 6, the bottom end of the connecting steel structure 10 is bolted or welded to the end of the prestressed steel structure 4, and a stiffening plate 13 is provided in the connection area between the two.

[0025] like Figure 1 、 Figure 4 、 Figure 5 As shown, in this embodiment, preferably, bolt pads 12 are provided at the installation positions of the bolts 11 of the prestressed steel structure 4 and the connecting steel structure 10. In this embodiment, preferably, the prestressed steel strand 6 can be in a straight line parallel to the bottom of the hollow slab (such as Figure 1 ), a broken line type with high ends and low middle (such as Figure 2 ) or a curved line with high ends and low center. In this embodiment, the prestressed steel strand 6 can preferably be tensioned using either a one-end anchored and one-end tensioned method or a two-end tensioned method. In this embodiment, the mounting components of the prestressed steel strand 6 preferably include one or more of an anchoring node 8, a turning node 9, and a tensioning node 7. In this embodiment, the main body of the connecting steel structure 10 is preferably an I-beam.

[0026] The construction method of the above-mentioned transverse reinforcement system of the existing hollow slab beam bridge is: comprising the steps of: 1) repairing and reinforcing the existing hollow slab beam bridge that has developed transverse defects; 2) based on the mechanical analysis of the existing hollow slab beam bridge, combined with on-site inspection and testing, obtaining the cross-sectional deformation curves at different positions of the existing hollow slab beam bridge, and considering the convenience of construction, determining the number and position of the transverse reinforcement units, determining the number, line type, tensioning method and tensioning control force of the prestressed steel bundles 6 in the prestressed steel structure 4 at each location, and determining whether the main body of the prestressed steel structure 4 adopts the I-beam 2 according to the position of the prestressed steel structure 4. It is a box-section steel 5; 3) corresponding prestressed steel bundles 6 and their installation components are installed inside each prestressed steel structure 4, connecting steel structures 10 are installed at both ends of the prestressed steel structure 4 and stiffening plates 13 are set in the connection area to form each transverse reinforcement unit; 4) each transverse reinforcement unit is installed at the corresponding longitudinal position of the hollow slab beam, wherein the prestressed steel structure 4 and the connecting steel structure 10 are respectively installed on the lower side of the hollow slab bottom 1 and the outer side of the outer web 3 of the hollow slab side plate through bolts 11; 5) the corresponding prestressed steel bundles 6 are tensioned and fixed according to the determined tensioning method and tensioning control force to protect the prestressed steel bundles 6.

[0027] Preferably, in step 1), the repair and reinforcement treatment includes peeling and cleaning the hinge joints, re-pouring the hinge joints, and repairing the bridge deck pavement; in step 2), when the location of the prestressed steel structure 4 requires frequent inspection, maintenance or replacement of the prestressed steel bundles 6, the main body of the prestressed steel structure 4 adopts I-beams 2; when the location of the prestressed steel structure 4 requires ensuring the safety of the prestressed steel bundles 6, the main body of the prestressed steel structure 4 adopts box-section steel 5; in step 5), when the prestressed steel bundles 6 are tensioned, the displacement of each hollow slab must be detected during the tensioning process to ensure the overall safety of the existing hollow slab beam bridge; the tensioning task is carried out symmetrically from the mid-span to both ends.

[0028] The present invention combines steel structure and prestressing to transversely reinforce the existing hollow slab beam bridge, and bears stress as a whole with the existing hollow slab beam bridge, which can promote the coordination of structural stress and deformation, greatly enhance the transverse integrity and load-bearing performance of the existing hollow slab beam bridge, and effectively improve the fatigue performance of the steel structure. Moreover, the steel structure is arranged at the lower edge and mainly bears tensile stress, which conforms to the material properties. In short, the safety and durability of the existing hollow slab beam bridge are improved. Compared with conventional transverse reinforcement, the present invention mainly adopts steel structure components, avoids formwork, brackets and maintenance processes, and has no redundant materials, which can greatly improve work efficiency and reduce construction difficulty. Moreover, the increase in the deadweight of the existing hollow slab beam bridge is small, which is beneficial to the safety of the structure itself.

[0029] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all such improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A transverse reinforcement system for an existing hollow slab girder bridge, characterized by: It includes transverse reinforcement units distributed longitudinally along the hollow slab beam body, and the transverse reinforcement units include prestressed steel structures installed on the bottom side of the hollow slab by bolts and connecting steel structures installed on the outside of the web of the side plate of the hollow slab by bolts; the prestressed steel structure is arranged horizontally and the main body is an I-beam or box-section steel. The prestressed steel structure is preset with prestressed steel bundles and their installation components before installation. After installation, the prestressed steel bundles are tensioned and fixed. The prestressed steel bundles extend from one end of the prestressed steel structure to the other end; the connecting steel structures are located at both ends of the prestressed steel structure. The bottom end of the structure is bolted or welded to the end of the prestressed steel structure and a stiffening plate is provided in the connection area between the two; bolt mounting positions of the prestressed steel structure and the connecting steel structure are both provided with bolt pads; the prestressed steel bundle adopts a straight line type parallel to the bottom of the hollow slab, a broken line type with high ends and low middle, or a curved line type with high ends and low middle; the prestressed steel bundle adopts a tensioning method of anchoring at one end and tensioning at the other end or a tensioning method of tensioning at both ends; the installation components of the prestressed steel bundle include one or more of anchoring nodes, turning nodes, and tensioning nodes; the main body of the connecting steel structure is an I-beam.

2. The construction method of the existing hollow slab girder bridge transverse reinforcement system according to claim 1, characterized in that: The method includes the following steps: 1) repairing and reinforcing an existing hollow slab girder bridge that has developed transverse defects; 2) obtaining cross-sectional deformation curves of the existing hollow slab girder bridge at different locations based on mechanical analysis of the existing hollow slab girder bridge and combined with on-site inspection and testing, and determining the number and location of transverse reinforcement units, considering the convenience of construction, determining the number, line type, tensioning method and tensioning control force of prestressed steel strands in each prestressed steel structure, and determining whether the main body of the prestressed steel structure adopts an I-beam or a box-section according to the location of the prestressed steel structure. Steel; 3) Install the corresponding prestressed steel strands and their installation components inside each prestressed steel structure, install connecting steel structures at both ends of the prestressed steel structure and set stiffening plates in the connection area to form each transverse reinforcement unit; 4) Install each transverse reinforcement unit at the corresponding longitudinal position of the hollow slab beam, wherein the prestressed steel structure and the connecting steel structure are respectively installed on the bottom side of the hollow slab and the outer side of the outer web of the hollow slab side plate by bolts; 5) Tension and fix the corresponding prestressed steel strands according to the determined tensioning method and tensioning control force to protect the prestressed steel strands.

3. The construction method of the existing hollow slab girder bridge transverse reinforcement system according to claim 2, characterized in that: In step 1), the repair and reinforcement treatment includes peeling and cleaning the hinge joints, re-filling the hinge joints, and repairing the bridge deck pavement.

4. The construction method of the existing hollow slab girder bridge transverse reinforcement system according to claim 2, characterized in that: In step 2), when the location of the prestressed steel structure requires frequent inspection, maintenance or replacement of prestressed steel strands, the main body of the prestressed steel structure adopts I-beams; when the location of the prestressed steel structure requires ensuring the safety of the prestressed steel strands, the main body of the prestressed steel structure adopts box-section steel.

5. The construction method of the existing hollow slab girder bridge transverse reinforcement system according to claim 2, characterized in that: In step 5), when the prestressed steel tendons are tensioned, the displacement of each hollow slab must be detected during the tensioning process to ensure the overall safety of the existing hollow slab beam bridge; the tensioning task is carried out symmetrically from the mid-span to both ends.

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