Construction method of large-span and large-height-difference steel box girder pushing system

Abstract

The invention relates to a construction method of a large-span and large-height-difference steel box girder pushing system, which adopts the combination of various components such as a steel box girder, an existing pier, a temporary bracket and a bailey beam, and greatly improves the stability and flexibility of construction. The bracket and the bracket are arranged on the opposite sides of the temporary support and the existing pier, so that the safety and the adaptability of the structure are ensured. In addition, due to the design of the splicing adjusting beam, the splicing height of the steel box beam can be adjusted according to specific requirements, and construction operation is greatly facilitated; the pushing system comprises a temporary support and a front guide beam and is further provided with equipment such as a jack and a micro jack, and the equipment jointly acts on pushing operation of the steel box beam. Through reasonable connection and supporting design, the stability in the pushing process is effectively guaranteed, and the construction possibility under complex conditions is greatly improved. The incremental launching system can effectively reduce the construction cost, shorten the construction period and improve the construction safety, and has remarkable technical benefits.

Description

Technical Field

[0001] The invention relates to the technical field of bridge engineering and its construction, and in particular to a construction method of a large-span and large-height-difference steel box girder jacking system. Background Art

[0002] Long-span bridges can not only effectively solve traffic bottleneck problems, but also reduce the project's floor space and improve traffic efficiency. Among many bridge structures, steel box girders have gradually become the mainstream choice for long-span bridges due to their excellent mechanical properties and economy. However, the construction technology of steel box girders is relatively complex, especially under large height differences and special terrain conditions, the construction difficulty and technical requirements are significantly increased.

[0003] Traditional steel box girder construction methods mainly include hoisting, assembly and erection. These methods can meet the construction requirements to a certain extent, but they still face many challenges in practical applications. First, traditional construction methods often rely on a large number of temporary support structures and hoisting equipment, which not only increases the construction cost but also prolongs the construction period. In addition, during the construction process, the stability and safety of the steel box girder are difficult to be effectively guaranteed, especially when the height difference is constructed, the beam body is prone to deformation, tilting and other problems, which in turn affect the construction quality. In order to overcome the above problems, many researchers and engineers have begun to explore new construction technologies and equipment. Among them, the top-pushing method, as an emerging construction technology, has gradually attracted widespread attention. The top-pushing method gradually pushes the steel box girder to the designed position by setting up special top-pushing equipment on the built components to reduce the dependence on temporary support. This method shows good adaptability and stability in the construction of long-span bridges, especially for construction with large height differences and complex terrain.

[0004] However, the existing jacking technology still has some shortcomings. For example, the thrust and speed need to be precisely controlled during the jacking process to ensure the safety and stability of the beam. In addition, the setting of the jacking equipment and its connection with the main structure also need special attention to avoid unnecessary vibration and deformation during the jacking process. Therefore, how to design an efficient and stable jacking system has become the focus of current technical research.

[0005] In summary, facing the ever-increasing traffic demand and increasingly complex construction environment, higher requirements are placed on the construction technology of large-span and large-height-difference steel box girders. Therefore, a new type of large-span and large-height-difference steel box girder jacking system is urgently needed, which aims to improve the construction efficiency and safety of steel box girders through reasonable structural design and construction steps. The proposal and implementation of this technology will provide new solutions for the construction of large-span bridges in the future and promote the further development and innovation of bridge construction technology. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a construction method for a large-span and large-height-difference steel box girder jacking system.

[0007] The construction method of this large-span and large-height-difference steel box girder top-pushing system includes the following steps:

[0008] Step 1: temporary brackets are set on both sides of the existing piers, bottom support beams are installed above the existing piers between the temporary brackets, and assembly brackets are installed above the bottom support beams to form an assembly system;

[0009] Step 2: Assemble the steel box girder on the assembly bracket and install the guide beam system at the front end of the steel box girder;

[0010] Step 3: Temporary supports are set at intervals on the steel box girder jacking route, jacks are installed on the temporary supports, and cushion beams are installed on the jacks; fixed frames are installed on one side of the cushion beam, and movable frames are installed between the fixed frames, and micro jacks and bottom pads are installed at the bottom of the movable frames to form a jacking system; the steel box girder is pushed by the jacks, and the height of the movable frames is adjusted by the micro jacks;

[0011] Step 4: Use movable frames and fixed frames as temporary supports for steel box girders, and use cushion beams and reverse cushion beams to lower beams with large height differences.

[0012] Preferably, the assembly system includes a steel box girder, existing piers, temporary supports and Bailey beams, temporary supports are arranged on both sides of the existing piers, the temporary supports include pipe piles, pile caps, pillow beams and main beams, support corbels and support brackets are arranged on the opposite sides of the temporary supports and the existing piers, pier top corbels and pier top brackets are arranged on both sides of the existing piers, bottom supporting beams are arranged on the support brackets and the pier top brackets, and the bottom supporting beams are located above the water level line.

[0013] Preferably, struts are arranged at intervals on the bottom supporting beam, and the struts are connected to the bottom supporting beam through strut anchor bolts. The upper part of the struts is provided with a top drag beam and a distribution beam, and the distribution beam is provided with a Bailey beam. Both sides of the Bailey beam are connected to temporary supports on both sides through anchor rods and Bailey beam anchor bolts. The Bailey beam is provided with an assembly support, and the bottom of the assembly support is provided with a base, which is located on the top surface of the Bailey beam. The top of the assembly support is provided with an assembly adjustment beam, and the assembly adjustment beam directly supports the steel box beam.

[0014] Preferably, the jacking system includes a temporary support, a leading guide beam and a permanent pier. The temporary supports are distributed at intervals on the jacking route. A jack is provided on the main beam of the temporary support, a pad beam is provided on the jack, a fixed frame is provided on one side of the pad beam, a movable frame is provided between the two fixed frames, a micro-jack and a bottom pad are provided at the bottom of the movable frame, the movable frame and the fixed frames on both sides are temporarily fixed by connecting rods, and a top pad is provided on the movable frame; during the jacking process, the micro-jack at the bottom of the movable frame is gradually adjusted to ensure the set elevation of the top pad.

[0015] Preferably, the guide beam system includes a front guide beam at the front end of the steel box beam, the front part of the front guide beam has a guide beam boss, the guide beam boss has a built-in groove, the built-in groove has a reverse built-in jack, the built-in jack and the guide beam boss are connected by a vertical fixing rod, a transverse fixing rod and a fixed end, the built-in jack is connected to a reverse pad beam by a connecting frame, the reverse pad beam is opposite to the pad beam on the temporary support, during jacking, the reverse pad beam and the pad beam are movably connected by a first connecting block, a hinge, a connecting shaft and a second connecting block, and during pushing, the reverse pad beam and the pad beam are disconnected.

[0016] Preferably, the assembly system, the jacking system, the guide beam system and the steel box girder are assembled and manufactured on the assembly bracket, and the assembly bracket adjusts the height according to the assembly requirements of the steel box girder. After the assembly and manufacturing of the steel box girder is completed, the guide beam system is installed at its front end, and then the jacking system is used to push the steel box girder forward to the temporary bracket and permanent pier in front; when the steel box girder reaches the set position and the beam is dropped, the movable frame and the fixed frame are used as temporary support, and the micro-jack at the bottom of the movable frame can be adjusted to meet the set elevation requirement of the top pad, and the pad beam and the reverse pad beam are used to drop the beam with a large height difference. The built-in jack and the jack act relative to each other at the same time to meet the needs of dropping the beam with a large height difference.

[0017] The large-span and large-height-difference steel box girder jacking system is obtained by any of the methods described above.

[0018] The beneficial effects of the present invention are:

[0019] 1) The present invention adopts a combination of multiple components such as steel box beams, existing piers, temporary brackets, Bailey beams, etc. in the assembly system, which greatly improves the stability and flexibility of the construction. The safety and adaptability of the structure are ensured by setting brackets and brackets on the opposite sides of the temporary brackets and the existing piers. In addition, the design of the assembly adjustment beam allows the assembly height of the steel box beam to be adjusted according to specific needs, which greatly facilitates the construction operation.

[0020] 2) The jacking system of the present invention includes temporary supports, front guide beams, and is also equipped with jacks and micro jacks and other equipment, which work together to push the steel box beam. Through reasonable connection and support design, the stability during the jacking process is effectively guaranteed, which greatly improves the possibility of construction under complex conditions. The jacking system can effectively reduce construction costs, shorten construction period, and improve construction safety, with significant technical benefits.

[0021] 3) The guide beam system of the present invention can achieve efficient connection and support during the lifting and pushing process by means of built-in grooves, reverse jacks, etc., to ensure the stability of the steel box beam during construction. Especially in the case of large height difference beam drop, the synergy of the built-in jack and the pushing equipment can achieve precise control of the steel box beam to ensure that it falls safely and smoothly to the predetermined position. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the construction system in the assembly stage;

[0023] Figure 2 This is a schematic diagram of the construction system in the jacking stage;

[0024] Figure 3 This is a schematic diagram of pushing to a temporary support;

[0025] Figure 4 This is a schematic diagram of jacking to the permanent pier;

[0026] Figure 5 It is a schematic diagram of the front guide beam;

[0027] Figure 6 Schematic diagram of cushion beam and temporary support.

[0028] Explanation of the reference numerals: 1. existing pier; 2. water level line; 3. temporary support; 4. pipe pile; 5. support bracket; 6. support bracket; 7. pier top bracket; 8. pier top bracket; 9. support rod; 10. bottom support beam; 11. support rod anchor bolt; 12. top support beam; 13. distribution beam; 14. Bailey beam; 15. Bailey beam anchor bolt; 16. anchor rod; 17. base; 18. assembly support; 19. assembly adjustment beam; 20. steel box beam; 21. pile cap; 22. pillow beam; 23. main beam; 2 4. Jack; 25. Cushion beam; 26. Fixed frame; 27. Movable frame; 28. Bottom pad; 29. ​​Connecting rod; 30. Top pad; 31. Mini jack; 32. Front guide beam; 33. Guide beam boss; 34. Built-in groove; 35. Built-in jack; 36. Fixed end; 37. Horizontal fixing rod; 38. Vertical fixing rod; 39. Reverse cushion beam; 40. Permanent pier; 41. Connecting frame; 42. First connecting block; 43. Hinge; 44. Connecting shaft; 45. Second connecting block. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0030] Embodiment 1

[0031] As an example, Figures 1 to 6 As shown, the construction method of this large-span and large-height-difference steel box girder top-pushing system includes the following steps:

[0032] Step 1: Construction preparation:

[0033] Step 2: Building the assembly system:

[0034] Step 3: Assembly of steel box girder 20:

[0035] Step 4: Construction and operation of the push system:

[0036] S41. Setting of temporary support 3:

[0037] Temporary supports 3 are arranged at intervals on the jacking route. Jacks 24 are installed on the main beams 23 of the temporary supports 3, and cushion beams 25 are installed on the jacks 24.

[0038] S42, installation of fixed frame 26 and movable frame 27:

[0039] A fixed frame 26 is installed on one side of the cushion beam 25, and a movable frame 27 is installed between the fixed frames 26. A micro jack 31 and a bottom pad 28 are installed at the bottom of the movable frame 27 to ensure its stability.

[0040] S43, push operation:

[0041] The steel box girder 20 is pushed by the jack 24, and the movable frame 27 is temporarily fixed to the fixed frames 26 on both sides by the connecting rod 29 to ensure the stability of the structure during the pushing process. During the pushing process, the micro jack 31 at the bottom of the movable frame 27 is gradually adjusted to ensure the set elevation of the top pad 30.

[0042] Step 5: Beam drop operation:

[0043] When the steel box girder 20 reaches the set position, the movable frame 27 and the fixed frame 26 are used as temporary supports. The micro jack 31 at the bottom of the movable frame 27 is adjusted to ensure that the set elevation requirement of the top pad 30 is met.

[0044] The cushion beam 25 and the reverse cushion beam 39 are used to perform the beam lowering operation with a large height difference, and the built-in jack 35 and the jack 24 act against each other at the same time to ensure the smooth lowering of the steel box beam 20.

[0045] Step 6: Construction completion and inspection:

[0046] S61. Construction site cleaning: Tidy up the construction site and remove waste and debris generated during the construction process.

[0047] S62. Quality inspection: Carry out quality inspection on the completed steel box girder 20 and its connecting parts to ensure compliance with the design and relevant standards.

[0048] Embodiment 2

[0049] As another embodiment, this embodiment 2 proposes, on the basis of the embodiment 1, a more specific construction method of a large-span and large-height-difference steel box girder top-pushing system, wherein steps 1 to 3 are specifically as follows:

[0050] Step 1: Construction preparation:

[0051] S11. Material preparation: Purchase the required steel box girder 20 and temporary support 3 materials, including pipe piles 4, pile caps 21, bolsters 22, main beams 23, Bailey beams 14, anchor rods 16, connectors, etc., and conduct material inspection and acceptance.

[0052] S12. Construction site layout: Build temporary facilities at the construction site to ensure the safety and smooth flow of the construction area.

[0053] S13. Setting of permanent support: Setting and constructing permanent pier 40 according to design requirements.

[0054] Step 2: Building the assembly system:

[0055] S21. Inspection and cleaning of existing pier 1: Inspect the existing pier 1 to ensure that its bearing capacity meets the requirements, and clean the pier top and surrounding environment.

[0056] S22, temporary support 3 construction:

[0057] Temporary supports 3 are set on both sides of the existing pier 1, and pipe piles 4, pile caps 21, bolsters 22 and main beams 23 are installed. Support brackets 5 and support brackets 6 are set on the opposite sides of the supports to enhance the support stability. Pier top brackets 7 and pier top brackets 8 are set on both sides of the existing pier 1.

[0058] Install the bottom support beam 10 between the support bracket 6 and the pier top bracket 8, and ensure that it is level. Install the support rod 9, and connect it with the top support beam 12 through the support rod anchor bolt 11 to ensure the overall stability of the temporary support 3.

[0059] Installation of S23 and Bailey beam 14:

[0060] A top drag beam and a distribution beam 13 are installed on the upper part of the support rod 9 to ensure that they are fixedly connected to the support rod 9.

[0061] A Bailey beam 14 is installed on the distribution beam 13 and connected to the brackets on both sides by using anchor rods 16 and Bailey beam anchor bolts 15 to ensure the stability of the Bailey beam 14 .

[0062] S24, construction of assembly bracket 18:

[0063] The assembly bracket 18 is installed, and the bottom base 17 is placed on the top surface of the Bailey beam 14 to ensure its load-bearing capacity. The assembly adjustment beam 19 is installed on the top of the assembly bracket 18, and its height is adjusted to meet the assembly requirements of the steel box beam 20.

[0064] Step 3: Assembly of steel box girder 20:

[0065] S31, assembly of steel box girder 20:

[0066] The steel box girder 20 is assembled on the assembly bracket 18, and each component is assembled step by step to ensure the firmness of each connection point. During the assembly process, necessary quality inspections are carried out to ensure that the assembly quality meets the design requirements.

[0067] S32, Installation of guide beam system:

[0068] A guide beam system is installed at the front end of the steel box beam 20 to ensure that the guide beams are firmly butted and connected.

[0069] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0070] Embodiment 3

[0071] As another embodiment, this embodiment 3 is proposed on the basis of embodiments 1 and 2. This method uses a large-span and large-height-difference steel box girder top-pushing system, such as Figures 1 to 6 As shown, it includes an assembly system, a jacking system and a guide beam system.

[0072] like Figure 1 As shown, the assembly system includes a steel box girder 20, an existing pier 1, a temporary support 3, and a Bailey beam 14. Temporary supports 3 are arranged on both sides of the existing pier 1. The temporary support 3 includes pipe piles 4, pile caps 21, pillow beams 22, and main beams 23. The temporary support 3 and the existing pier 1 are opposite to each other. Support brackets 5 and support brackets 6 are arranged. Pier top brackets 7 and pier top brackets 8 are arranged on both sides of the existing pier 1. Bottom support beams 10 are arranged on the support brackets 6 and the pier top brackets 8. The bottom support beams 10 are located above the water level 2. The support brackets arranged at intervals are arranged on the support brackets 6 and the pier top brackets 8. The rod 9 is connected to the top supporting beam 12 through the support rod anchor bolt 11. The upper part of the support rod 9 is provided with a top drag beam and a distribution beam 13. The distribution beam 13 is provided with a Bailey beam 14. The two sides of the Bailey beam 14 are connected to the two side brackets through anchor rods 16 and Bailey beam anchor bolts 15. The Bailey beam 14 is provided with an assembly bracket 18. The bottom of the assembly bracket 18 is provided with a base 17. The base 17 is located on the top surface of the Bailey beam 14. The top of the assembly bracket 18 is provided with an assembly adjustment beam 19. The assembly adjustment beam 19 directly supports the steel box beam 20.

[0073] like Figures 2 to 4 As shown, the jacking system includes a temporary support 3, a front guide beam 32, and a permanent pier 40. The temporary support 3 is distributed at intervals on the jacking route. A jack 24 is provided on the main beam 23 of the temporary support 3, and a cushion beam 25 is provided on the jack 24. A fixed frame 26 is provided on one side of the cushion beam 25. A movable frame 27 is provided between the two fixed frames 26. A micro jack 31 and a bottom pad 28 are provided at the bottom of the movable frame 27. The movable frame 27 and the fixed connections on both sides can be temporarily fixed by connecting rods 29. A top pad 30 is provided on the movable frame 27.

[0074] like Figure 5 and Figure 6 As shown, the guide beam system includes a front guide beam 32 at the front end of the steel box beam 20, the front part of the front guide beam 32 has a guide beam boss 33, the guide beam boss 33 has a built-in groove 34, the built-in groove 34 has a reverse built-in jack 35, the built-in jack 35 and the guide beam boss 33 are connected by a vertical fixing rod 38, a horizontal fixing rod 37, and a fixed end 36, the built-in jack 35 is connected to a reverse pad beam 39 by a connecting frame 41, the reverse pad beam 39 is opposite to the pad beam 25 on the temporary support 3, when lifting, the reverse pad beam 39 and the pad beam 25 are movably connected by the first connecting block 42, the hinge 43, the connecting shaft 44, and the second connecting block 45, when pushing, the reverse pad beam 39 is disconnected from the pad beam 25.

[0075] Based on the above-mentioned assembly system, jacking system and guide beam system, the steel box girder 20 is assembled on the assembly bracket 18. The assembly bracket 18 can adjust the height according to the assembly requirements of the steel box girder 20. After the assembly and production of the steel box girder 20 is completed, the guide beam system is installed at its front end, and then the jacking system is used to push the steel box girder 20 forward to the front temporary bracket 3 and the permanent pier 40; when the steel box girder 20 reaches the set position and drops the beam, the movable frame 27 is used. The fixed frame 26 is used as a temporary support, and the micro jack 31 at the bottom of the movable frame 27 can be adjusted to meet the set elevation requirements of the top pad 30. The pad beam 25 and the reverse pad beam 39 are used to drop the beam with a large height difference. The built-in jack 35 and the jack 24 act relative to each other at the same time to meet the needs of dropping the beam with a large height difference.

[0076] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiments 1 and 2 can be referenced to each other and will not be described in detail in this application.

[0077] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. A construction method for a large-span and large-height-difference steel box girder jacking system, characterized in that: The steps include: Step 1: temporary brackets are set on both sides of the existing piers, bottom support beams are installed above the existing piers between the temporary brackets, and assembly brackets are installed above the bottom support beams to form an assembly system; Step 2: Assemble the steel box girder on the assembly bracket and install the guide beam system at the front end of the steel box girder; Step 3: Temporary supports are set at intervals on the steel box girder jacking route, jacks are installed on the temporary supports, and cushion beams are installed on the jacks; fixed frames are installed on one side of the cushion beam, and movable frames are installed between the fixed frames, and micro jacks and bottom pads are installed at the bottom of the movable frames to form a jacking system; the steel box girder is pushed by the jacks, and the height of the movable frames is adjusted by the micro jacks; Step 4: Use movable frames and fixed frames as temporary supports for steel box girders, and use cushion beams and reverse cushion beams to lower beams with large height differences.

2. The construction method of the large-span and large-height-difference steel box girder jacking system according to claim 1 is characterized in that: The assembly system includes steel box girder, existing piers, temporary supports and Bailey beams. Temporary supports are set on both sides of the existing piers. The temporary supports include pipe piles, pile caps, pillow beams and main beams. Support corbels and support brackets are set on the opposite sides of the temporary supports and the existing piers. Pier top corbels and pier top brackets are set on both sides of the existing piers. Bottom supporting beams are set on the support brackets and the pier top brackets, and the bottom supporting beams are located above the water level line.

3. The construction method of the large-span and large-height-difference steel box girder jacking system according to claim 1 is characterized in that: Struts are arranged at intervals on the bottom supporting beam, and the struts are connected to the bottom supporting beam through strut anchor bolts. The upper part of the struts is provided with a top drag beam and a distribution beam, and the distribution beam is provided with a Bailey beam. Both sides of the Bailey beam are connected to temporary supports on both sides through anchor rods and Bailey beam anchor bolts. There is an assembly support on the Bailey beam, and the bottom of the assembly support is provided with a base, which is located on the top surface of the Bailey beam. There is an assembly adjustment beam on the top of the assembly support, and the steel box beam is directly supported on the assembly adjustment beam.

4. The construction method of the large-span and large-height-difference steel box girder jacking system according to claim 1 is characterized in that: The jacking system includes temporary supports, leading guide beams and permanent piers. The temporary supports are distributed at intervals on the jacking route. There are jacks on the main beams of the temporary supports, and there are pad beams on the jacks. There is a fixed frame on one side of the pad beam, and a movable frame is provided between the two fixed frames. The bottom of the movable frame has a micro jack and a bottom pad. The movable frame and the fixed frames on both sides are temporarily fixed by connecting rods, and there is a top pad on the movable frame. During the jacking process, the micro jack at the bottom of the movable frame is gradually adjusted to ensure the set elevation of the top pad.

5. The construction method of the large-span and large-height-difference steel box girder jacking system according to claim 1 is characterized in that: The guide beam system includes a front guide beam at the front end of the steel box beam, the front part of the front guide beam is provided with a guide beam boss, the guide beam boss has a built-in groove, the built-in groove is provided with a reverse built-in jack, the built-in jack and the guide beam boss are connected by a vertical fixing rod, a transverse fixing rod and a fixed end, the built-in jack is connected with a reverse pad beam by a connecting frame, the reverse pad beam is opposite to the pad beam on the temporary support, during jacking, the reverse pad beam and the pad beam are movably connected by a first connecting block, a hinge, a connecting shaft and a second connecting block, and during pushing, the reverse pad beam and the pad beam are disconnected.

6. The construction method of the large-span and large-height-difference steel box girder jacking system according to claim 1 is characterized in that: The assembly system, jacking system, guide beam system and steel box girder are assembled and manufactured on the assembly bracket. The assembly bracket adjusts the height according to the assembly requirements of the steel box girder. After the assembly and manufacturing of the steel box girder is completed, the guide beam system is installed at its front end, and then the jacking system is used to push the steel box girder forward to the temporary bracket and permanent pier in front; when the steel box girder reaches the set position and drops the beam, the movable frame and the fixed frame are used as temporary supports, and the micro-jack at the bottom of the movable frame can be adjusted to meet the set elevation requirements of the top pad, and the pad beam and the reverse pad beam are used to drop the beam with a large height difference. The built-in jack and the jack act relative to each other at the same time to meet the needs of dropping the beam with a large height difference.

7. The large-span and large-height-difference steel box girder jacking system is characterized by: Obtained by the method according to any one of claims 1 to 6.

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