Hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system and construction method

Abstract

The present application relates to a kind of hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system and construction method, comprising: pier column, prefabricated hollow slab, bent cap, pier platform support synchronous jacking system, demolition-free steel sleeve box concrete heightening cushion stone and beam bottom synchronous grading jacking pre-arch system;Beam bottom synchronous grading jacking pre-arch system includes slide rail and steel pipe support, steel pipe support slides on slide rail, steel pipe support top is equipped with jack, and props below the center line of single prefabricated hollow slab.The beneficial effects of the present application are: through pier platform support synchronous jacking system, the synchronous jacking reverse slope adjustment of hollow slab bridge is realized, and the construction efficiency of hollow slab bridge synchronous jacking reverse slope adjustment splicing widening is greatly improved;Through beam bottom synchronous grading jacking pre-arch system, the bottom of hollow slab center line is jacked.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction, and in particular relates to a synchronous jacking and reverse slope adjustment splicing and widening system and construction method for hollow slab bridges. Background Technology

[0002] With the rapid development of my country's economy, there are increasingly higher demands on the traffic capacity of existing expressways. Many existing expressways, while structurally sound and in good working order, suffer from traffic congestion due to insufficient road width and limited capacity, failing to meet the growing traffic demands brought about by economic development. Reconstructing expressways is prohibitively expensive and time-consuming. Therefore, the reconstruction and expansion of existing expressways has become a cost-effective solution in terms of both economics and time. However, during reconstruction and expansion, when the elevation and angle of the new and old bridges are inconsistent, traditional construction methods suffer from problems such as long lifting and post-construction periods, and potential damage to existing bridges.

[0003] In summary, for the construction of the synchronous jacking and reverse slope adjustment splicing widening system for hollow slab bridges, it is currently very important to find a new system and construction method for widening embankments that is fast, easy to operate, and has high reliability in construction quality. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a system and construction method for synchronous jacking, reverse slope adjustment, splicing and widening of hollow slab bridges.

[0005] This hollow slab bridge synchronous jacking reverse slope adjustment splicing and widening system includes: a synchronous jacking system for piers, precast hollow slabs, cap beams, and pier supports, a non-removable steel caisson concrete heightening pad, and a synchronous graded jacking pre-arching system for the bottom of the beam;

[0006] The top of the pier support synchronous jacking system is lifted by jacks together, and the distribution beam is placed on the distribution beam;

[0007] The original pad stone exists on the cap beam of the pier column. The non-removable steel-casing concrete raised pad stone is poured on the original pad stone to support the end of the precast hollow slab. Jacks are set between adjacent non-removable steel-casing concrete raised pad stones to support the hinge joint of the precast hollow slab.

[0008] The synchronous graded lifting and pre-arching system at the bottom of the beam includes a slide rail and a steel pipe support. The steel pipe support slides on the slide rail and is equipped with a jack at the top, which supports the beam below the centerline of a single precast hollow slab.

[0009] Preferably, the synchronous jacking system for the pier supports includes a concrete cushion layer, grouting pipes, and steel pipe supports. Grouting is performed below the grouting pipes to form a hardened grouting body. Above the grouting pipes, a concrete cushion layer and a precast concrete base slab foundation for installing the jacking supports are laid in sequence. The steel pipe supports are set on the precast concrete base slab foundation of the jacking supports. A heightening support beam, a jack, and a distribution beam are installed in sequence on the upper part of the steel pipe supports. The upper part of the distribution beam is connected to the precast hollow slab. The pier column is connected and fixed to the steel pipe supports by tie bars.

[0010] Preferably, the steel pipe supports are fixed together as a whole by scissor braces and connecting rods; the top of the jack is equipped with a distribution beam, the precast hollow slab is placed on the distribution beam, and grouting material is provided on the top of the distribution beam to ensure that the top of the distribution beam is in close contact with the bottom of the precast hollow slab.

[0011] Preferably, the non-removable steel casing concrete raised pad includes the original pad, the non-removable steel casing, and micro-expansion concrete. The non-removable steel casing concrete raised pad is located on the upper part of the cap beam. The non-removable steel casing is installed on the outside of the original pad. The non-removable steel casing is equipped with closely spaced ribs. A breakage-proof steel pad is set between the two non-removable steel casings. A jack is installed on the upper part of the breakage-proof steel pad. A breakage-proof steel pad is installed between the top of the jack and the bottom of the hinge joint of the precast hollow slab. Temporary support steel plates are set on both sides of the jack. Micro-expansion concrete is constructed inside the non-removable steel casing. A support is installed on the upper part of the micro-expansion concrete. The precast hollow slab is placed on the support on the non-removable steel casing concrete raised pad.

[0012] Preferably, the bottom of the beam-bottom synchronous graded lifting pre-arching system has three rows of grouting pipes installed at the corresponding positions of the center line of the precast hollow slab. Grouting is injected into the bottom of the grouting pipes to form a grouting hardened body. A concrete pad and a precast concrete base plate for the guide rail are laid on the upper part of the grouting hardened body. The top of the precast concrete base plate for the guide rail is equipped with a side slide rail and a middle slide rail. The bottom of the steel pipe support is equipped with a T-shaped sliding shaft and a sliding brace rod, which are respectively installed in the middle slide rail and the side slide rail. The upper part of the steel pipe support is sequentially equipped with a height-adjusting pad beam, a jack, and a distribution beam. The upper part of the distribution beam is connected to the bottom of the precast hollow slab. Counterweights are set on both sides of the upper part of the precast hollow slab. The steel pipe support is fixed to the ground by ropes and steel rods.

[0013] The construction method for this hollow slab bridge synchronous jacking, reverse slope adjustment, splicing, and widening system includes the following steps:

[0014] Step 1: Precast hollow slab lifting construction: The construction pier support synchronous lifting system lifts the precast hollow slabs using jacks;

[0015] Step 2: Multi-point synchronous jacking and lateral slope adjustment construction: Gradually adjust the height of the jacks on the synchronous jacking system of each pier support to adjust the slope of the precast hollow slab;

[0016] Step 3: Concrete pouring and raising of the steel casing and pad stone construction: Concrete raising of the steel casing and pad stone without dismantling according to the original pad stone construction, and place the precast hollow slab on it.

[0017] Step 4: Synchronous graded lifting and pre-arching construction at the bottom of the beam: The pre-arching system is synchronously lifted and graded at the bottom of the beam at the position corresponding to the center line of the precast hollow slab, and counterweights are set on both sides of the upper part of the precast hollow slab. By adjusting the jacks, each precast hollow slab is pre-arched individually.

[0018] As a preferred option, the pier has supports. In step four, after the precast hollow slab is lifted, the supports are removed and the original pad stone is roughened. A non-removable steel sleeve is installed on the outside of the original pad stone. A jack is set between the two non-removable steel sleeves. A damage-proof steel pad is installed on the top of the jack at the bottom of the hinge joint. After the non-removable steel sleeve is installed, micro-expansion concrete is constructed to form a non-removable steel sleeve concrete raised pad stone. Supports are installed on the top of the non-removable steel sleeve concrete raised pad stone, and the precast hollow slab is placed on the supports.

[0019] As a preferred option, there is a fifth step after step four, which is: dismantling the synchronous jacking system of the pier support and the synchronous graded jacking pre-arching system of the beam bottom, and constructing the hinge joints of the precast hollow slabs, the road structure and the guardrail.

[0020] The beneficial effects of this invention are:

[0021] 1) This invention achieves synchronous jacking and reverse slope adjustment of hollow slab bridges through a synchronous jacking system for pier supports, which greatly improves the construction efficiency of synchronous jacking, reverse slope adjustment, splicing and widening of hollow slab bridges.

[0022] 2) This invention uses a synchronous graded lifting and pre-cambering system at the bottom of the beam to lift the bottom of the hollow slab centerline, which makes it easier and faster to control the pre-camber of the slab beam, ensures that the pre-camber loss of the slab beam is small after widening, and improves the load-bearing capacity of the slab beam. It can achieve good technical and economic benefits when applied to actual engineering projects. Attached Figure Description

[0023] Figure 1 This is a longitudinal elevation diagram of the hollow slab bridge synchronous jacking, reverse slope adjustment, splicing and widening system;

[0024] Figure 2 This is a schematic diagram of the cross-section of the synchronous jacking, reverse slope adjustment, splicing and widening system of the hollow slab bridge before the reverse slope adjustment;

[0025] Figure 3 This is a schematic diagram of the cross-section of the synchronous jacking, reverse slope adjustment, splicing and widening system of the hollow slab bridge after the reverse slope adjustment;

[0026] Figure 4 This is a schematic diagram of the cross-section of the raised steel casing being filled with concrete to elevate the pad stone.

[0027] Figure 5 This is a schematic diagram of the plan view of the jacking steel casing being filled with concrete to raise the pad stone;

[0028] Figure 6 This is a schematic diagram of the longitudinal elevation of the synchronous graded lifting and pre-arching system at the bottom of the beam;

[0029] Figure 7 This is a detailed schematic diagram of the foundation of the synchronous graded lifting and pre-arching system at the bottom of the beam;

[0030] Figure 8 This is a schematic diagram of the longitudinal and transverse sections of the synchronous graded lifting and pre-arching of the beam bottom.

[0031] In the diagram: 1-Pile foundation, 2-Pile cap, 3-Concrete cushion layer, 4-Grouting hardened body, 5-Grouting pipe, 6-Piercing support for precast concrete slab foundation, 7-Steel pipe support, 8-Extension beam, 9-Pier column, 10-Jack, 11-Distribution beam, 12-Support, 13-Precast hollow slab, 14-Scissor brace, 15-Connecting rod, 16-Guardrail, 17-Hinge joint, 18-Grouting material, 19-Original cushion stone, 2 0-Closely fitted rib plate, 21-No-removal steel casing, 22-Micro-expansion concrete, 23-No-removal steel casing concrete raised pad stone, 24-Damage-proof steel pad plate, 25-Temporary support steel plate, 26-Cap beam, 27-Cap beam centerline, 28-Counterweight block, 29-Steel chisel, 30-Rope, 31-Precast concrete base plate for guide rail, 32-Side slide rail, 33-Central slide rail, 34-T-shaped slide shaft, 35-Sliding brace. Detailed Implementation

[0032] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0033] Example 1

[0034] As one example, such as Figures 1 to 8As shown, this system for synchronously lifting, adjusting, splicing, and widening hollow slab bridges includes: 1. Pile foundation; 2. Abutment; 3. Concrete cushion layer; 4. Grouting hardened body; 5. Grouting pipe; 6. Precast concrete base slab foundation for lifting support; 7. Steel pipe support; 8. Extension beam; 9. Pier column; 10. Jack; 11. Distribution beam; 12. Bearing; 13. Precast hollow slab; 14. Scissor brace; 15. Connecting rod; 16. Guardrail; 17. Hinge joint; 18. Grouting material; 19. Original pad stone; and 10. Closely connected ribs. 20. Steel casing without dismantling; 21. Micro-expansion concrete; 22. Concrete raised pad stone for steel casing without dismantling; 23. Damage-proof steel pad plate; 24. Temporary support steel plate; 25. Cap beam; 26. Centerline of cap beam; 27. Counterweight block; 28. Steel chisel; 29. ​​Rope; 30. Precast concrete base plate for guide rail; 31. Side slide rail; 32. Middle slide rail; 33. T-shaped sliding shaft; 34. Sliding brace; 35. Including the synchronous jacking system for pier supports and the synchronous graded jacking and pre-arching system for beam bottom.

[0035] The top of the synchronous jacking system of several pier supports is jacked by jacks 10 to lift the distribution beam 11, and the precast hollow slab 13 is set on the distribution beam 11.

[0036] The original pad stone 19 exists on the cap beam 26 of the pier column 9. The non-removable steel box concrete heightening pad stone 23 is poured on the original pad stone 19 to support the end of the precast hollow slab 13. Jacks 10 are set between adjacent non-removable steel box concrete heightening pad stones 23 to support the hinge joint 17 of the precast hollow slab 13.

[0037] The synchronous graded lifting and pre-arching system at the bottom of the beam includes a slide rail and a steel pipe support 7. The steel pipe support 7 slides on the slide rail, and a jack 10 is provided on the top of the steel pipe support 7, which supports the beam below the centerline of a single precast hollow slab 13.

[0038] The aforementioned pier support synchronous jacking system consists of a concrete cushion layer 3, a grouting hardened body 4, grouting perforated pipes 5, a precast concrete base slab foundation 6 for the jacking support, steel pipe supports 7, extension beams 8, pier columns 9, jacks 10, and distribution beams 11. Two rows of grouting perforated pipes 5 are installed at the designed location on the outside of the pier column 9. Grouting is performed by connecting the grouting perforated pipes 5 to a high-pressure grouting machine to form the grouting hardened body 4. After the grouting hardened body 4 reaches its design strength, a foundation pit is excavated on top of it, and excess grouting perforated pipes 5 are cut off. The concrete cushion layer 3 is then laid sequentially, followed by the installation of steel pipe supports 7, extension beams 8, pier columns 9, jacks 10, and distribution beams 11. A precast concrete base slab foundation 6 for the jacking support is installed. The precast concrete base slab foundation 6 for the jacking support is prefabricated in the factory and has embedded connectors on its top. A steel pipe support 7 is installed on the precast concrete base slab foundation 6 for the jacking support. A heightening pad beam 8, a jack 10, and a distribution beam 11 are installed on its upper part in sequence. The upper part of the distribution beam 11 is connected to the precast hollow slab 13. The precast hollow slab 13 is lifted by synchronously adjusting the jack 10. To improve the stability of the jacking system, tie bars are installed on the pier column 9 and connected and fixed to the steel pipe support 7.

[0039] The multi-point synchronous jacking and transverse slope adjustment technology is carried out through the synchronous jacking system of pier support for the splicing and widening of hollow slab bridges, and the steel pipe supports 7 are fixed into a whole by scissor braces 14 and connecting rods 15; grouting material 18 is set on the top of the distribution beam 11 to ensure that the top of the distribution beam is in close contact with the bottom of the precast hollow slab 13.

[0040] The non-removable steel casing concrete heightening pad 23 is composed of the original pad 19, closely spaced ribs 20, non-removable steel casing 21, and micro-expansion concrete 22, and is located on the upper part of the cap beam 26. After the precast hollow slab 13 is lifted, the support 12 is removed, and the original pad 19 is roughened. The non-removable steel casing 21 is installed on the outside of the original pad 19. The non-removable steel casing 21 is processed in the factory and has closely spaced ribs 20 inside. A breakage-proof steel pad 24 is set between the two non-removable steel casings 21. A jack 10 is installed on the top of the breakage-proof steel pad 24. The breakage-proof steel pad 24 is installed on the top of the jack 10 at the bottom of the hinge joint 17. Temporary support steel plates 25 are set on both sides of the jack to stabilize the lifted precast hollow slab 13. After the non-removable steel casing 21 is installed, the micro-expansion concrete 22 is constructed. After curing, a new support 12 is installed on its upper part, and the precast hollow slab 13 is placed on it.

[0041] Example 2

[0042] As another embodiment, this second embodiment, based on the first embodiment, proposes a synchronous jacking and reverse slope adjustment splicing and widening system for hollow slab bridges. Specifically, the synchronous graded jacking and pre-arching system at the bottom of the beam is as follows:

[0043] The pre-arching system with synchronous graded lifting at the bottom of the beam has three rows of grouting pipes 5 installed at the corresponding positions of the center line of the precast hollow slab 13. Grouting is injected into the bottom of the grouting pipes 5 to form a grouting hardened body 4. A concrete pad layer 3 and a guide rail precast concrete base plate 31 are laid on the top of the grouting hardened body 4. The top of the guide rail precast concrete base plate 31 is provided with a side slide rail 32 and a middle slide rail 33. The bottom of the steel pipe support 7 is provided with a T-shaped sliding shaft 34 and a sliding support rod 35, which are respectively installed in the middle slide rail 33 and the side slide rail 32. The upper part of the steel pipe support 7 is sequentially installed with a height-adjusting pad beam 8, a jack 10 and a distribution beam 11. The upper part of the distribution beam 11 is connected to the bottom of the precast hollow slab 13. Counterweight blocks 28 are provided on both sides of the upper part of the precast hollow slab 13. The steel pipe support 7 is fixed to the ground by ropes 30 and steel rods 29 to improve the stability of the entire pre-arching system.

[0044] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0045] Example 3

[0046] As another embodiment, this embodiment three proposes a construction method for a hollow slab bridge synchronous jacking and reverse slope adjustment splicing and widening system based on embodiments one and two. The main construction steps are as follows:

[0047] Step 1, Foundation Construction: Conduct on-site survey of the synchronous jacking and reverse slope adjustment splicing and widening system for hollow slab bridges, and carry out foundation construction such as the synchronous jacking system for pier supports and the synchronous graded jacking and pre-arching system for beam bottom;

[0048] Construction of jacking up precast hollow slab 13: Steel pipe support 7 is set on the precast concrete base 6 of the jacking support. The upper part of the support beam 8, jack 10 and distribution beam 11 are installed in sequence. The upper part of the distribution beam 11 is connected to the precast hollow slab 13. The precast hollow slab 13 is jacked up by synchronously adjusting the jack 10. In order to improve the stability of the jacking system, tie bars are set on the pier 9 and connected and fixed to the steel pipe support 7.

[0049] Step 2: Multi-point synchronous jacking and transverse slope adjustment construction: The hollow slab bridge splicing and widening synchronous jacking and reverse slope adjustment construction is carried out through the pier support synchronous jacking system. The steel pipe supports 7 are fixed into a whole by scissor braces 14 and connecting rods 15; grouting material 18 is placed on the top of the distribution beam 11 to ensure that the top of the distribution beam is in close contact with the bottom of the precast hollow slab 13. The jacks 10 are adjusted to make the transverse slope ratio of the distribution beam 11 2%. Before adjustment, the lowering end is higher than the jacking end; the jacks at the jacking end are gradually adjusted to carry out reverse slope adjustment. The jacking height of the jacks 10 at the jacking end is higher than the jacking height of the jacks 10 at the lowering end. After adjustment, the jacking end is higher than the lowering end. The transverse slope ratio is gradually adjusted to 2%.

[0050] Step 3: Construction of Lifting Steel Jacket and Pouring Concrete to Raise Pad Stone: After the precast hollow slab 13 is lifted, the support 12 is removed, and the original pad stone 19 is roughened. The non-removable steel jacket 21 is installed on the outside of the original pad stone 19. The non-removable steel jacket 21 is processed in the factory and has closely spaced ribs 20 inside. A breakage-proof steel pad 24 is set between the two non-removable steel jackets 21. A jack 10 is installed on the top of the breakage-proof steel pad 24. The breakage-proof steel pad 24 is installed on the top of the jack 10 at the bottom of the hinge joint 17. Temporary support steel plates 25 are set on both sides of the jack to stabilize the lifted precast hollow slab 13. After the non-removable steel jacket 21 is installed, micro-expansion concrete 22 is poured. After curing, a new support 12 is installed on its top, and the precast hollow slab 13 is placed on it.

[0051] Step 4: Synchronous Staged Lifting and Pre-arching Construction at the Beam Bottom: First, foundation treatment is carried out. Three rows of grouting pipes 5 are installed at the corresponding positions of the center line of the precast hollow slab 13. Grouting is performed by connecting the grouting pipes 5 to the high-pressure grouting machine to form a grouting hardened body 4. After the grouting hardened body 4 reaches the design strength, a foundation pit is excavated on top of it, and excess grouting pipes 5 are cut off. Then, a concrete pad layer 3 and a precast concrete base plate 31 for guide rails are laid in sequence. The precast concrete base plate 31 for guide rails is precast in the factory, and side slide rails 32 and middle slide rails 33 are installed on its top; steel pipe supports are also provided. 7. A T-shaped sliding shaft 34 and a sliding support rod 35 are installed at the bottom of the steel pipe support 7, respectively, inside the middle sliding rail 33 and the side sliding rail 32. The upper part of the steel pipe support 7 is sequentially installed with a height-adjusting pad beam 8, a jack 10, and a distribution beam 11. The upper part of the distribution beam 11 is connected to the bottom of the precast hollow slab 13. By adjusting the jack 10, each precast hollow slab 13 is pre-arched individually, and counterweights 28 are set on both sides of the upper part of the precast hollow slab 13. The steel pipe support 7 is moved to the design position and fixed with ropes 30 and steel rods 29 to improve the stability of the entire pre-arching system.

[0052] Dismantling: Dismantle the pier support synchronous jacking system and the beam bottom synchronous graded jacking pre-arching system supports;

[0053] Construction of ancillary structures for splicing and widening hollow slab bridges: Construction of hinge joint 17, road surface structure, and guardrail 16.

[0054] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

Claims

1. A construction method of a hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system, characterized in that, The synchronous jacking and slope adjustment splicing and widening system for hollow slab bridges includes: a synchronous jacking system for piers, precast hollow slabs, cap beams, and pier supports; a non-removable steel caisson concrete heightening pad; and a synchronous graded jacking and pre-arching system for the bottom of the beam. The top of the pier support synchronous jacking system is lifted by jacks, and the distribution beam is placed on the distribution beam; The original pad stone exists on the cap beam of the pier column. The non-removable steel-casing concrete raised pad stone is poured on the original pad stone to support the end of the precast hollow slab. Jacks are set between adjacent non-removable steel-casing concrete raised pad stones to support the hinge joint of the precast hollow slab. The synchronous graded lifting and pre-arching system at the bottom of the beam includes a slide rail and a steel pipe support. The steel pipe support slides on the slide rail and is equipped with a jack at the top, which supports the beam below the centerline of a single precast hollow slab. The aforementioned non-removable steel-casing concrete raised pad includes the original pad, the non-removable steel casing, and micro-expansion concrete. The non-removable steel-casing concrete raised pad is located on the upper part of the cap beam. The non-removable steel casing is installed on the outside of the original pad, and closely spaced ribs are installed inside the non-removable steel casing. A breakage-proof steel pad is installed between the two non-removable steel casings. A jack is installed on the upper part of the breakage-proof steel pad. A breakage-proof steel pad is installed between the top of the jack and the bottom of the hinge joint of the precast hollow slab. Temporary support steel plates are installed on both sides of the jack. Micro-expansion concrete is constructed inside the non-removable steel casing. A support is installed on the upper part of the micro-expansion concrete. The precast hollow slab is placed on the support on the non-removable steel-casing concrete raised pad. The aforementioned beam bottom synchronous graded lifting pre-arching system has three rows of grouting pipes installed at the corresponding positions of the center line of the precast hollow slab. Grouting is injected into the bottom of the grouting pipes to form a grout hardened body. A concrete pad and a precast concrete base plate for guide rails are laid on the upper part of the grout hardened body. Side rails and middle rails are installed on the top of the precast concrete base plate for guide rails. T-shaped sliding shafts and sliding bracing rods are installed at the bottom of the steel pipe support and are respectively installed in the middle rail and side rail. A height-adjusting pad beam, jacks and distribution beams are installed on the upper part of the steel pipe support. The upper part of the distribution beam is connected to the bottom of the precast hollow slab. Counterweights are installed on both sides of the upper part of the precast hollow slab. The steel pipe support is fixed to the ground by ropes and steel rods. The construction method for this hollow slab bridge synchronous jacking, reverse slope adjustment, splicing, and widening system includes the following steps: Step 1: Precast hollow slab lifting construction: The construction pier support synchronous lifting system lifts the precast hollow slabs using jacks; Step 2: Multi-point synchronous jacking and lateral slope adjustment construction: Gradually adjust the height of the jacks on the synchronous jacking system of each pier support to adjust the slope of the precast hollow slab; Step 3: Concrete pouring and raising of the steel casing and pad stone construction: Concrete raising of the steel casing and pad stone without dismantling according to the original pad stone construction, and place the precast hollow slab on it. Step 4: Synchronous Staged Lifting and Pre-arching Construction at the Bottom of the Beam: At the corresponding position on the centerline of the precast hollow slab, the pre-arching system is synchronously lifted and graded at the bottom of the beam. Counterweights are placed on both sides of the upper part of the precast hollow slab. Each precast hollow slab is pre-arched individually by adjusting the jacks. Supports exist on the piers. After the precast hollow slabs are lifted, the supports are removed, and the original pad stones are roughened. A non-removable steel sleeve is installed on the outside of the original pad stone. A jack is placed between two non-removable steel sleeves, and a breakage-proof steel pad is installed on top of the jack at the bottom of the hinge joint. After the non-removable steel sleeves are installed, micro-expansion concrete is used to form a concrete raised pad stone for the non-removable steel sleeves. Supports are installed on top of the concrete raised pad stone, and the precast hollow slabs are placed on the supports.

2. The construction method of the hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system according to claim 1, characterized in that, The aforementioned pier support synchronous jacking system includes a concrete cushion layer, grouting pipes, and steel pipe supports. Grouting is performed below the grouting pipes to form a hardened grouting body. Above the grouting pipes, a concrete cushion layer and a precast concrete base slab foundation for installing the jacking support are laid in sequence. The steel pipe supports are set on the precast concrete base slab foundation of the jacking support. A heightening support beam, jacks, and distribution beams are installed in sequence on the upper part of the steel pipe supports. The upper part of the distribution beams is connected to the precast hollow slabs. The pier columns are connected and fixed to the steel pipe supports by tie bars.

3. The construction method of the hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system according to claim 2, characterized in that, The steel pipe supports are fixed together as a whole by scissor braces and connecting rods; the top of the jack is equipped with a distribution beam, on which the precast hollow slab is placed. Grouting material is placed on the top of the distribution beam to ensure that the top of the distribution beam is in close contact with the bottom of the precast hollow slab.

4. The construction method of the hollow slab bridge synchronous jacking reverse slope adjustment splicing widening system according to claim 1, characterized in that, Step five follows step four, which involves dismantling the synchronous jacking system for the pier supports and the synchronous graded jacking pre-arching system for the bottom of the beams, and constructing the hinge joints of the precast hollow slabs, the road structure, and the guardrails.

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