A construction method for improving the operational safety of single-column pier bridges

Abstract

This invention belongs to the field of bridge construction technology. Specifically, it is a construction method for improving the operational safety of single-column pier bridges, comprising the following steps: A. symmetrically fixing and installing a first annular steel strip between the abutment cap beam and the box girder web; B. symmetrically fixing and installing a second annular steel strip between the pier and the bottom plate of the box girder; C. symmetrically fixing and installing a third annular steel strip between the pier and the bottom plate of the box girder. This invention features a simple construction process, rapid installation, and a stable and reliable structure; while preventing and mitigating the safety risk of lateral overturning of single-column pier bridges, it also improves the bridge's seismic isolation and damping capabilities.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology, specifically, it is a construction method for improving the operational safety of single-column pier bridges. Background Technology

[0002] Among the existing methods for reinforcing single-column pier bridges, increasing the spacing between the side bearings, changing the single-supported central pier to a double-supported one, replacing the single-column pier with a round-ended column, and adding additional columns can ensure that no void occurs under the basic combination. However, these methods have drawbacks: they require checking the potential impact on clearance after the cap beam is lengthened, and the construction process involves rebar installation, concrete pouring, box girder jacking, and bearing replacement. Bearing replacement requires traffic closure, making it quite cumbersome. Adding pull-out restraint devices to the side piers has almost no impact on the original structural stress pattern and is a smaller-scale project, but replacing tension / compression bearings is complex and difficult, as is constructing pull-out reinforcement, which requires removing the bridge deck pavement and closing traffic. Therefore, existing methods are significant for addressing the lateral overturning risk of single-column pier bridges, but they generally involve numerous construction procedures, a large impact area, and high economic investment. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to improve the earthquake resistance and disaster reduction level of bridges while meeting the lateral overturning resistance requirements of single-column pier bridges with a more economical and reasonable reinforcement treatment strategy.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is to provide a construction method for safe lifting of a single-column pier bridge, comprising the following steps:

[0005] A. A first annular steel strip is symmetrically installed between the bridge abutment cap beam and the box girder web. The two ends of the first annular steel strip are welded to the anchor plate. The anchor plate connected to the first annular steel strip is fixed to the surface of the bridge abutment cap beam and the box girder web by high-strength bolts.

[0006] B. A second ring steel strip is symmetrically installed between the pier and the bottom plate of the box girder. The two ends of the second ring steel strip are welded to the anchor plate. The anchor plate connected to the second ring steel strip is fixed to the surface of the pier and the bottom plate of the box girder by high-strength bolts.

[0007] C. A third annular steel strip is symmetrically installed between the pier and the bottom plate of the box girder. The two ends of the third annular steel strip are welded to the anchor plates. The anchor plates connected to the third annular steel strip are fixed to the surface of the pier and the bottom plate of the box girder by high-strength bolts.

[0008] Preferably, in step A, the first annular steel strip is circular in shape, the anchoring point of the first annular steel strip on the surface of the box girder web is higher than the stop block, and the anchoring point of the first annular steel strip on the surface of the cap beam is located outside the stop block.

[0009] Preferably, in step A, variable-width grooves are opened at intervals on the inner and outer sides of the first annular steel strip, the groove depth is less than the ring width, and the first annular steel strip is in a continuous "S" shape.

[0010] Preferably, in step A, two first annular steel strips are symmetrically arranged along the bridge direction, and the first annular steel strips are in their initial state.

[0011] Preferably, in step B, the second annular steel strip is circular in shape and has a continuous "S" shape.

[0012] Preferably, in step C, the third annular steel strip is circular in shape, the third annular steel strip is in a continuous "S" shape, the inner diameter of the third annular steel strip is larger than the outer diameter of the second annular steel strip, and both the third annular steel strip and the second annular steel strip are in their initial state.

[0013] This invention features a simple construction process, rapid installation, and a stable and reliable structure; it not only prevents and mitigates the safety risk of lateral overturning of single-column pier bridges but also improves the seismic isolation and damping level of bridges. Attached Figure Description

[0014] Figure 1 This is the overall layout plan of the single-column pier bridge facade.

[0015] Figure 2 This is a plan view of the overall layout of a single-column pier bridge.

[0016] Figure 3 Overall layout plan for improving the operational safety of single-column pier bridges.

[0017] Figure 4 A partial cross-sectional structural diagram of the abutment to improve the operational safety of a single-column pier bridge.

[0018] Figure 5 A partial cross-sectional structural diagram of the pier to improve the operational safety of single-column pier bridges.

[0019] Figure 6 This is a partial cross-sectional structural diagram of the abutment of a single-column pier bridge under lateral torsional load.

[0020] Figure 7 This is a partial cross-sectional structural diagram of a single-column pier bridge under lateral torsional load.

[0021] Figure 8 This is a partial cross-sectional structural diagram of the abutment of a single-column pier bridge under transverse seismic load.

[0022] Figure 9 This is a partial cross-sectional structural diagram of a single-column pier bridge under transverse seismic load.

[0023] Figure 10This is a partial cross-sectional structural diagram of the abutment of a single-column pier bridge under vertical seismic load.

[0024] Figure 11 This is a partial cross-sectional structural diagram of the pier of a single-column bridge under vertical seismic load. Detailed Implementation

[0025] The present invention will now be described in detail with reference to the accompanying drawings.

[0026] like Figures 1 to 11 As shown, the present invention provides a construction method for improving the operational safety of a single-column pier bridge, comprising the following steps:

[0027] A. A first annular steel strip 7 is symmetrically installed between the bridge abutment cap beam 1 and the web of the box girder 4. The two ends of the first annular steel strip 7 are welded to the first anchor plate 9 and the second anchor plate 8. The first anchor plate 9 and the second anchor plate 8 connected to the first annular steel strip 7 are fixed to the surface of the bridge abutment cap beam 1 and the web of the box girder 4 by high-strength bolts 10.

[0028] Double supports 2 are installed on the bridge abutment cap beam 1. The bridge pier 6 in the middle is a single-column pier, and a single support 5 is installed on the top of the pier 6. The box girder 4 is an integral structure, supported by the double supports 2 of the bridge abutment cap beam 1 and the single support 5 of the pier 6. The stop block 3 is cast integrally with the bridge abutment cap beam 1 and is located on both sides of the box girder 4. The first annular steel strip 7 is circular in shape, with widening grooves set at intervals on the inner and outer sides of the first annular steel strip 7. The groove depth is less than the ring width. The first annular steel strip 7 is in a continuous "S" shape. Two first annular steel strips 7 are symmetrically arranged along the bridge direction. The upper end of the first annular steel strip 7 is welded to the second anchor plate 8. Next, the lower end of the first annular steel strip 7 is welded to the first anchor plate 9, and the second anchor plate 8 is fixed to the surface of the web of the box girder 4 by high-strength bolts 10. The gap between the second anchor plate 8 and the surface of the web of the box girder 4 is filled with pressure-injected steel glue. The anchoring point of the first annular steel strip 7 on the surface of the web of the box girder 4 is higher than the stop block 3. The first anchor plate 9 is fixed to the abutment cap beam 1 by high-strength bolts 10, and the gap between the first anchor plate 9 and the surface of the abutment cap beam 1 is filled with pressure-injected steel glue. The anchoring point of the first annular steel strip 7 on the surface of the cap beam 1 is located outside the stop block 3. After the above steps are completed, the first annular steel strip 7 is in its initial state, see Figures 3-4 .

[0029] B. A second annular steel strip 12 is symmetrically installed between the pier 6 and the bottom plate of the box girder 4. The two ends of the second annular steel strip 12 are welded to the third anchor plate 14 and the fourth anchor plate 13. The third anchor plate 14 and the fourth anchor plate 13 connected to the second annular steel strip 12 are fixed to the surface of the pier 6 and the bottom plate of the box girder 4 by high-strength bolts 10.

[0030] The second annular steel strip 12 is circular in shape and has a continuous "S" shape. The upper end of the second annular steel strip 12 is welded to the fourth anchor plate 13, and the lower end of the second annular steel strip 12 is welded to the third anchor plate 14. The fourth anchor plate 13 is fixed to the bottom plate of the box girder 4 by high-strength bolts 10. The gap between the fourth anchor plate 13 and the surface of the bottom plate of the box girder 4 is filled with pressure-injected steel glue. The third anchor plate 14 is fixed to the pier 6 by high-strength bolts 10. The gap between the third anchor plate 14 and the surface of the pier 6 is filled with pressure-injected steel glue.

[0031] C. A third ring steel strip 11 is symmetrically installed between the pier 6 and the bottom plate of the box girder 4. The two ends of the third ring steel strip 11 are welded to the third anchor plate 14 and the fourth anchor plate 13. The third anchor plate 14 and the fourth anchor plate 13 connected to the third ring steel strip 11 are fixed to the surface of the pier 6 and the bottom plate of the box girder 4 by high-strength bolts 10.

[0032] The third annular steel strip 11 is circular in shape and has a continuous "S" shape. The inner diameter of the third annular steel strip 11 is larger than the outer diameter of the second annular steel strip 12. The upper end of the third annular steel strip 11 is welded to the fourth anchor plate 13, and the lower end is welded to the third anchor plate 14. The fourth anchor plate 13 is fixed to the bottom plate of the box girder 4 by high-strength bolts 10. The gap between the fourth anchor plate 13 and the surface of the bottom plate of the box girder 4 is filled tightly with pressure-injected steel glue. The third anchor plate 14 is fixed to the pier 6 by high-strength bolts 10. The gap between the third anchor plate 14 and the surface of the pier 6 is filled tightly with pressure-injected steel glue. After the above steps are completed, both the second annular steel strip 12 and the third annular steel strip 11 are in their initial state. See [link to original text]. Figure 5 .

[0033] Under heavy and eccentric extreme vehicle loads, box girder 4 undergoes lateral torsion along the support 2 of the abutment cap beam 1 on the eccentric side. The first annular steel band 7 on the eccentric side is circumferentially compressed, limiting further development of the lateral torsion of box girder 4. On the non-eccentric side, the first annular steel band 7 is circumferentially stretched, restraining further development of the lateral torsion of box girder 4. Simultaneously, the second annular steel band 12 and the third annular steel band 11 at the pier 6 on the eccentric side are circumferentially compressed, limiting further development of the lateral torsion of box girder 4. On the non-eccentric side, the second annular steel band 12 and the third annular steel band 11 are circumferentially stretched, restraining further development of the lateral torsion of box girder 4. The first annular steel band 7, the second annular steel band 12, and the third annular steel band 11, together with the abutment cap beam 1 and the pier 6, form a complete lateral anti-overturning system for box girder 4. This system provides multiple safety barriers for box girder 4, ensuring its safety and stability under eccentric extreme vehicle loads. (See...) Figures 6-7 .

[0034] Under transverse seismic loads, the box girder 4 undergoes overall lateral displacement, altering the distance between it and the stop block 3. The first annular steel band 7 on the side with increased spacing undergoes tensile deformation, which reacts on the box girder 4, limiting further lateral displacement. Conversely, the first annular steel band 7 on the side with decreased spacing undergoes compressive deformation, which also reacts on the box girder 4, hindering further lateral displacement. Simultaneously, the second and third annular steel bands 12 and 11 on the side with increased spacing undergo compressive deformation, while those on the side with decreased spacing undergo tensile deformation, further restricting and constraining the lateral displacement of the box girder 4. The first annular steel band 7, second annular steel band 12, third annular steel band 11, and stop block 3 form a complete transverse seismic resistance system. This system provides a double safety barrier for the box girder 4, ensuring it does not collapse under lateral seismic loads. (See...) Figures 8-9 .

[0035] Under vertical seismic load, the monolithic box girder 4 undergoes vertical displacement, and the first annular steel band 7, the second annular steel band 12, and the third annular steel band 11 undergo tensile deformation. The tensile deformation of the first annular steel band 7, the second annular steel band 12, and the third annular steel band 11 reacts on the monolithic box girder 4, restricting its vertical displacement. (See...) Figures 10-11 .

[0036] Under the longitudinal seismic load, the box girder 4 undergoes overall displacement in the longitudinal direction. The first annular steel belt 7, the second annular steel belt 12, and the third annular steel belt 11 work together to limit and constrain the longitudinal displacement of the box girder 4, preventing excessive longitudinal displacement and avoiding collision and damage between the box girder 4 and the abutment breast wall.

[0037] The first annular steel band 7, the second annular steel band 12, and the third annular steel band 11 form a complete seismic isolation system for the box girder 4. This system allows the box girder 4 to undergo transverse, vertical, and longitudinal displacements, while simultaneously constraining and limiting large transverse, vertical, and longitudinal displacements, and even preventing girder collapse. Through the tensile or compressive deformation of the first annular steel band 7, the second annular steel band 12, and the third annular steel band 11, the system absorbs and dissipates seismic vibration impact energy, providing multiple safety redundancies for the integral box girder 4 and providing multiple safety barriers for the box girder 4 under seismic load conditions.

[0038] After the above steps are completed, the construction to improve the operational safety of the single-column pier bridge is finished.

Claims

1. A method for improving the operational safety of a single-column pier bridge, characterized in that, Includes the following steps: A. A first annular steel strip is symmetrically installed between the bridge abutment cap beam and the box girder web. The two ends of the first annular steel strip are welded to the anchor plates. The anchor plates connected to the first annular steel strip are fixed to the surface of the bridge abutment cap beam and the box girder web by high-strength bolts. A widening groove is opened at intervals on the inner and outer sides of the first annular steel strip. The groove depth is less than the ring width. The first annular steel strip is in the shape of a continuous "S". B. A second annular steel strip is symmetrically installed between the pier and the bottom plate of the box girder. The two ends of the second annular steel strip are welded to the anchor plates. The anchor plates connected to the second annular steel strip are fixed to the surface of the pier and the bottom plate of the box girder by high-strength bolts. The second annular steel strip is circular in shape and has a continuous "S" shape. C. A third annular steel strip is symmetrically installed between the pier and the bottom plate of the box girder. The two ends of the third annular steel strip are welded to the anchor plates. The anchor plates connected to the third annular steel strip are fixed to the surface of the pier and the bottom plate of the box girder by high-strength bolts. The third annular steel strip is circular in shape and has a continuous "S" shape. The inner diameter of the third annular steel strip is larger than the outer diameter of the second annular steel strip. Both the third annular steel strip and the second annular steel strip are in their initial state.

2. The method for improving the operational safety of single-column pier bridges according to claim 1, characterized in that, In step A, the first annular steel strip is circular in shape, the anchoring point of the first annular steel strip on the surface of the box girder web is higher than the stop block, and the anchoring point of the first annular steel strip on the surface of the cap beam is located outside the stop block.

3. The method for improving the operational safety of a single-column pier bridge according to claim 1, characterized in that, In step A, two first annular steel strips are symmetrically arranged along the bridge direction, and the first annular steel strips are in their initial state.

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