A through arch bridge and a cyclic pushing construction method thereof

Abstract

This invention discloses a method for constructing a through-arch bridge and its cyclic jacking construction. The method involves first erecting steel beam and arch rib assembly supports in a pre-designated assembly area. Steel beam segments are then assembled sequentially, with the first arch rib segment assembled simultaneously and a guide beam installed. After jacking the assembly a predetermined distance, steel beam and arch rib segments are assembled on the remaining supports, and non-tensioned hangers are installed. The entire assembly is then jacked again, and this process is repeated until the steel beam and arch rib assembly is complete and the rear guide beam is installed. The complete assembly is then jacked synchronously to the designed bridge location, the guide beam is removed, and the bridge is lowered. Finally, all hangers are tensioned to complete the system conversion, and temporary facilities are dismantled. This method saves assembly space, reduces land occupation outside the construction boundary and ecological damage, lowers temporary land use costs, and is environmentally friendly. By assembling and jacking the steel beams and arch ribs simultaneously, construction efficiency is improved, the construction period is shortened, and the investment in steel beam assembly supports is reduced, thus lowering energy consumption and emissions from steel production and overall construction costs.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a through-arch bridge and its cyclic jacking construction method. Background Technology

[0002] Arch bridges are a type of bridge structure with a long history and wide application. They are characterized by their majestic appearance and durable structure, and occupy an important position in the field of bridge construction. Based on different structural forms, arch bridges can be divided into three categories: through-deck, mid-deck, and superstructure.

[0003] The steel beams and arch ribs of the under-deck arch bridge are often constructed using the incremental launching method. In the construction of arch bridges spanning rivers, highways, railways, and canyons, the incremental launching method has become the preferred option for the construction of steel box girder arch bridges spanning rivers due to the constraints of navigation in the river channel below the bridge and the narrow construction site. This is because it has little impact on traffic and navigation below the bridge and a short construction period.

[0004] In existing technologies, the incremental launching construction process for steel beams and arch ribs of through-arch bridges is mainly divided into two categories:

[0005] (1) Construction process of beams first and arches later Representative technologies include the method of jacking up the steel box girder for long-span tied arch bridges (application number CN202310387476.4), which first positions the steel box girder by jacking, and then constructs the arch rib. Another method is the synchronous jacking and asynchronous installation of the arch girder for steel arch bridges (application number CN202311182613.7), which, although carrying the arch rib segment along with the steel girder during jacking, still requires hoisting the arch rib after the steel girder is in place; essentially, it is still a girder-first, arch-later process. The drawback of this type of process is that the steel girder and arch rib are constructed separately, resulting in a longer overall construction period.

[0006] (2) Construction technology of simultaneous launching of beam and arch Representative technologies include the basket-lift arch bridge construction method (application number CN202111634220.6) and the incremental launching construction method for large-span composite arch bridges (application number CN201811140835.1), among other patented technologies. This type of process requires the entire steel beam and arch rib to be assembled before synchronous launching. Its advantage is a shorter construction period compared to the beam-first-arch-later process, but it has extremely high requirements for the length of the assembly site. The assembly site must be long enough to accommodate the assembly of the steel beams and guide beams, making it unsuitable for construction scenarios with limited space.

[0007] In summary, existing arch bridge launching construction techniques present a contradiction: methods to shorten the construction period require large sites, while methods with limited sites inevitably require longer construction periods. Developing a construction method for under-deck arch bridges that can significantly shorten the construction period while maximizing the use of assembly space has become an urgent technical problem to be solved in this field. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a through-arch bridge and its cyclic jacking construction method for steel beams and arch bridges. This method enables the segmented synchronous assembly and jacking of steel beams and arch ribs, shortening the construction period while significantly reducing the length requirements of the assembly site, thus adapting to the construction needs of narrow spaces.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a cyclic jacking construction method for a through-arch bridge, the through-arch bridge comprising piers, the method utilizing temporary pier supports, steel beam assembly supports, and arch rib assembly supports during construction, characterized by comprising the following steps: S1. Construct the steel beam assembly support and the arch rib assembly support in the preset assembly area; S2. Assemble the first steel beam segment on the steel beam assembly support; S3. Continue assembling subsequent steel beam segments on the steel beam assembly support, while assembling the first arch rib on the arch rib assembly support and installing the guide beam; S4. Push the assembled steel beam segment and the first arch rib together to push out the pre-set assembly area a first predetermined distance. S5. On the steel beam assembly bracket and arch rib assembly bracket that are empty in the preset assembly area, continue to assemble the next steel beam segment and the next arch rib, and install the hangers between the already positioned arch rib segments. The hangers are in a non-tensioned state. S6. The assembly consisting of all assembled segments of steel beams and arch ribs is pushed out of the preset assembly area by a second predetermined distance. S7. Repeat steps S5 and S6, cyclically performing segmental assembly, hanger installation and overall jacking, until all steel beams and arch ribs are assembled, and then install the guide beam. S8. Simultaneously push the complete steel beam and arch rib assembly to the designed bridge position, remove the front guide beam and rear guide beam, and lower the beam; S9. Tension all the hangers, complete the bridge structural system conversion, and dismantle the temporary facilities.

[0010] Furthermore, the jacking operation can be carried out by walking jacking or pulling jacking.

[0011] Furthermore, when using a walking-type jacking method, the walking-type jacking device is arranged on the pier, the temporary pier support, and the steel beam assembly support.

[0012] Furthermore, when using a traction-type jacking method, the traction-type jacking device includes a slide rail installed on the top of the pier, the temporary pier support, and the steel beam assembly support, as well as a traction jack installed on the abutment, which is part of the pier; the traction jack is used to pull the assembly along the slide rail.

[0013] Secondly, the present invention provides a steel beam for a lower-bearing arch bridge specifically designed for the construction method described in the first aspect above. The steel beam is designed to be assembled from multiple segments in a cyclical manner at fixed positions, and temporarily connected to the corresponding arch ribs during assembly to form a composite structure capable of phased overall jacking. Preferably, the front and rear ends of the steel beam are respectively provided with detachable front and rear guide beams to assist in crossing support points during the jacking process.

[0014] Thirdly, the present invention provides a through-arch bridge constructed using the method described in the first aspect, comprising a steel beam, an arch rib, a suspender connecting the two, and a pier constructed by the method.

[0015] Compared with the prior art, the present invention has the following significant advantages: 1. Greatly saves construction space and also has environmental benefits. This invention employs a cyclical operation mode of segmented assembly and segmented jacking. The assembly area vacated after the jacking operation can be directly used for the next round of construction. The required fixed assembly area length only needs to meet the assembly requirements of one or a few segments, far less than the entire span length required by the traditional integral jacking method. This mode significantly reduces the required assembly site length, minimizes land occupation outside the construction boundary, lowers temporary land rental and reclamation costs, reduces damage to arable land and forest land, and meets environmentally friendly construction requirements.

[0016] 2. Significantly shortens the construction period and improves construction efficiency. This invention enables the simultaneous assembly and jacking of steel beams and arch ribs, with the installation of suspension rods completed concurrently during assembly. This method avoids the time losses associated with the phased construction of steel beams and arch ribs in the beam-then-arch process, while also eliminating the cumbersome procedure of installing slings on the bridge using cranes. The steel beam assembly, arch rib assembly, and suspension rod installation processes are carried out in a cyclical and parallel manner within a fixed site, achieving factory-style assembly line construction, effectively improving construction efficiency and shortening the overall construction period.

[0017] 3. Reduce construction costs and carbon emissions. This invention reduces the scale of investment in temporary facilities such as steel beam assembly supports, lowering the procurement and construction costs of support materials. Simultaneously, it reduces the usage cycle and number of shifts for large hoisting equipment, further compressing overall construction costs. The intensive use of resources such as steel avoids the additional energy consumption and emissions associated with support material processing during steel production, balancing economic and environmental benefits.

[0018] 4. Improve construction safety and structural quality Most of the high-altitude work was carried out on fixed, well-maintained ground supports, reducing high-risk operations above the bridge site. Fixed-position assembly helps ensure the accuracy of segmental connections and welding quality, thus improving the overall construction quality of the bridge structure.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0020] To more clearly illustrate the solutions in this invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of step S1 (construction of the foundation structure) of the construction method of the present invention.

[0022] Figure 2 This is a schematic diagram of step S2 (assembling the first steel beam) of the construction method of the present invention.

[0023] Figure 3 This is a schematic diagram of step S3 (assembling the steel beam and the first arch rib, and installing the guide beam) of the construction method of the present invention.

[0024] Figure 4 This is a schematic diagram of step S4 (first jacking) of the construction method of the present invention.

[0025] Figure 5 This is a schematic diagram of step S5 (assembling the next cycle segment and installing the hanger) of the construction method of the present invention.

[0026] Figure 6 This is a schematic diagram of step S6 (second jacking) of the construction method of the present invention.

[0027] Figure 7 This is a schematic diagram of step S7 of the construction method of the present invention (cyclic operation until assembly is completed, and then the guide beam is installed).

[0028] Figure 8 This is a schematic diagram of step S8 (overall jacking into place and lowering the beam) of the construction method of the present invention.

[0029] Figure 9 This is a schematic diagram of step S9 (tensioning the suspension rod to complete the construction) of the construction method of the present invention.

[0030] Explanation of reference numerals in the attached figures: 1. Bridge pier; 11. Bridge abutment; 12. Main pier; 13. Approach pier; 2. Temporary pier support; 3. Steel beam assembly support; 4. Arch rib assembly bracket; 5. Steel beams; 6. Arched ribs; 7. Lead beam; 8. Rear guide beam; 9. Hanging rod. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In a first typical embodiment, the present invention proposes a cyclic jacking construction method for a through-arch bridge, the through-arch bridge including piers. The method utilizes temporary pier supports, steel beam assembly supports, and arch rib assembly supports during construction, and includes the following steps: S1. Construct the steel beam assembly support and the arch rib assembly support in the preset assembly area; S2. Assemble the first steel beam segment on the steel beam assembly support; S3. Continue assembling subsequent steel beam segments on the steel beam assembly support, while assembling the first arch rib on the arch rib assembly support and installing the guide beam; S4. Push the assembled steel beam segment and the first arch rib together to push out the pre-set assembly area a first predetermined distance. S5. On the steel beam assembly bracket and arch rib assembly bracket that are empty in the preset assembly area, continue to assemble the next steel beam segment and the next arch rib, and install the hangers between the already positioned arch rib segments. The hangers are in a non-tensioned state. S6. The assembly consisting of all assembled segments of steel beams and arch ribs is pushed out of the preset assembly area by a second predetermined distance. S7. Repeat steps S5 and S6, cyclically performing segmental assembly, hanger installation and overall jacking, until all steel beams and arch ribs are assembled, and then install the guide beam. S8. Simultaneously push the complete steel beam and arch rib assembly to the designed bridge position, remove the front guide beam and rear guide beam, and lower the beam; S9. Tension all the hangers, complete the bridge structural system conversion, and dismantle the temporary facilities.

[0033] Furthermore, the jacking operation can be carried out by walking jacking or pulling jacking.

[0034] Furthermore, when using a walking-type jacking method, the walking-type jacking device is arranged on the pier, the temporary pier support, and the steel beam assembly support.

[0035] Furthermore, when using a traction-type jacking method, the traction-type jacking device includes a slide rail installed on the top of the pier, the temporary pier support, and the steel beam assembly support, as well as a traction jack installed on the abutment, which is part of the pier; the traction jack is used to pull the assembly along the slide rail.

[0036] A key optimization lies in the fact that throughout the entire construction cycle, all steel beam segments are assembled in the same location on the steel beam assembly support, and all arch rib segments are assembled in the same location on the arch rib assembly support. This "fixed-position" operation mode is fundamental to saving space.

[0037] In a second typical embodiment, the present invention proposes a steel beam for a lower-bearing arch bridge specifically designed for the construction method described in the first aspect above. The steel beam is designed to be assembled cyclically from multiple segments at fixed positions, and temporarily connected to the corresponding arch ribs during assembly to form a composite structure capable of phased overall jacking. Preferably, the front and rear ends of the steel beam are respectively provided with detachable front and rear guide beams to assist in crossing support points during the jacking process.

[0038] In a third typical embodiment, the present invention proposes a through-arch bridge constructed using the method described in the first aspect above, comprising a steel beam, an arch rib, a suspender connecting the two, and a pier constructed by the method.

[0039] The present invention will be further described in detail below with reference to the embodiments.

[0040] Example 1 This embodiment provides a cyclic jacking construction method for a through-arch bridge, involving construction components including pier 1, temporary pier support 2, steel beam assembly support 3, arch rib assembly support 4, steel beam 5, arch rib 6, front guide beam 7, rear guide beam 8, and hanger 9; the pier 1 includes abutment 11, main pier 12, and approach pier 13.

[0041] like Figures 1 to 9 As shown, taking a bridge with a specific span as an example, this construction method specifically includes the following steps: Step 1: Construction Preparation Reference Figure 1Permanent piers 1 (including abutment 11, main pier 12, and approach pier 13) are constructed at the bridge's designed location. Within the limited boundary area behind or to the side of abutment 11, temporary pier supports 2 and steel beam assembly supports 3 are constructed according to their calculated positions. The position of the arch rib assembly support 4 corresponds to that of the steel beam assembly support 3, typically located to its side and above. Jacking equipment (such as walking jacks) is installed at the predetermined positions of piers 1, temporary pier supports 2, and steel beam assembly supports 3, or sliding tracks are laid and traction equipment is installed.

[0042] Step 2: First cycle of assembly and pushing First, refer to Figure 2 The first section of steel beam 5, with a length of N1 meters, is assembled on the steel beam assembly support 3.

[0043] Next, the remaining N2-meter-long steel beam 5 is assembled on the steel beam assembly support 3. Meanwhile, referring to... Figure 3 The first arch rib 6 is assembled on the arch rib assembly bracket 4, and the guide beam 7 is installed at the front end of the steel beam. At this time, the assembled steel beam 5 and the first arch rib 6 form a preliminary assembly through temporary connectors (such as temporary bolts or welded plates).

[0044] Then, the jacking system is activated. Taking the walking jacking method as an example, the jacks arranged at each support point work together to push the steel beam 5-arch rib 6 assembly, together with the leading beam 7, forward by N3 meters. Figure 4 As shown. After the jacking, the steel beam assembly support 3 and the arch rib assembly support 4 are completely freed up.

[0045] Step 3: Second and subsequent cycles of assembly and jacking On the vacated support frame, the assembly work was repeated, assembling the next section of steel beam 5, which is N4 meters long, and the second arch rib 6, as follows. Figure 5 As shown. It should be noted that while assembling the second arch rib 6, the corresponding hangers 9 between the first and second arch ribs are installed. At this time, the hangers 9 are only installed in place, and their lower ends are temporarily fixed to the steel beam 5 without tensioning.

[0046] After assembly, a second jacking operation is performed, with a distance of N5 meters (refer to...). Figure 6 ).

[0047] Subsequently, the process was strictly repeated according to the cyclical steps of "assembly (steel beam + arch rib + installation of hangers) → jacking" (S5~S6). Figure 7 As shown, each cycle utilizes the exact same fixed support position, and the number of cycles is determined based on the total length of the bridge and the segment division.

[0048] Step 4: Final Push and System Transformation After all segments of steel beam 5 and arch rib 6 are assembled, and all intermediate hangers 9 are installed (not tensioned), install the rear guide beam 8 at the tail end of the steel beam (refer to...). Figure 7 ).

[0049] Then, the entire bridge superstructure, including all the suspenders, was simultaneously jacked up and precisely positioned on the main pier 12 and abutment 11 at the designed bridge location, as shown below. Figure 8 As shown. The front guide beam 7 and the rear guide beam 8 were removed, and the superstructure of the bridge was precisely lowered onto the permanent supports using jacks.

[0050] Finally, all the hangers 9 were tensioned according to the design sequence, so that the arch rib 6 and the steel beam 5 formed a tied arch structure system that shared the load, completing the transition from the construction state to the completed bridge state. Figure 9 As shown. All temporary supports (i.e., temporary pier support 2, steel beam assembly support 3, and arch rib assembly support 4) were removed, and construction was completed.

[0051] It should be noted that N1, N2, N3, N4, and N5 shown in the attached diagram are exemplary lengths. In actual construction, they can be flexibly divided according to bridge design, transportation conditions, and equipment capacity. Usually, N1+N2 is a standard cycle assembly length, and N3 and N5 are the corresponding jacking strokes. The two values ​​can be equal or adjusted according to the working conditions.

[0052] The following are two specific embodiments of the present invention: Example 2 This embodiment provides a cyclic launching construction method for a through-arch bridge, which adopts a step-by-step launching method. The specific steps are as follows: S1. In the pre-set assembly area, build steel beam assembly support 3 and arch rib assembly support 4, and simultaneously complete the construction of pier 1 consisting of abutment 11, main pier 12, approach pier 13, and temporary pier support 2, and arrange walking jacks on the above components. S2. Assemble the first steel beam segment, 20m long, on the steel beam assembly support 3; S3. Continue assembling the subsequent steel beam segment with a length of 30m on the steel beam assembly support 3, while assembling the first arch rib 6 with a length of 25m on the arch rib assembly support 4, and installing the front guide beam 7 at the front end of the assembly. S4. Start the walking jack to push the assembled steel beam and arch rib assembly out of the preset assembly area by 30m; S5. In the empty assembly area, assemble the next steel beam segment with a length of 30m and the next arch rib 6 with a length of 25m, and install the hanger 9 between the two arch ribs. The hanger 9 is kept in a non-tensioned state. S6. Activate the walking jack to push the entire assembly, including all assembled segments, out of the preset assembly area by 30m; S7. Repeat steps S5 and S6, and continue the operation until the steel beam 5 and arch rib 6 are fully assembled. The total assembly lengths are 200m and 180m respectively. Install the rear guide beam 8 at the rear end of the assembly. S8. Start the walking jacks to push the complete steel beam 5 and arch rib 6 assembly to the designed bridge position simultaneously, remove the front guide beam 7 and rear guide beam 8, and use jacks to lower the beams; S9. Tension all the hangers 9, dismantle the temporary pier support 2, steel beam assembly support 3 and arch rib assembly support 4, and complete the construction.

[0053] Example 3 This embodiment provides a cyclic launching construction method for a through-arch bridge, which adopts a pull-type launching method. The specific steps are as follows: S1. Erect steel beam assembly support 3 and arch rib assembly support 4 in the pre-set assembly area, and simultaneously complete the construction of pier 1 and temporary pier support 2. Set up a slide on the top of the above components, and arrange traction jacks at the bridge abutment 11 at the assembly start end. The construction steps of S2-S7 are the same as those in Example 2, except that in steps S4 and S6, the assembly is pushed along the slide by pulling jacks. S8. Start the traction jacks to push the complete steel beam 5 and arch rib 6 assembly to the designed bridge position simultaneously, remove the front guide beam 7 and rear guide beam 8, and use jacks to lower the beams; S9. Tension all the hangers 9, dismantle the temporary pier support 2, steel beam assembly support 3 and arch rib assembly support 4, and complete the construction.

[0054] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for the construction of a through arch bridge by the incremental launching method, said through arch bridge comprising piers (1), said method using, during construction, temporary pier supports (2), steel beam assembly supports (3) and arch rib assembly supports (4), characterised in that, Includes the following steps: S1. Erect the steel beam assembly bracket (3) and the arch rib assembly bracket (4) in the preset assembly area. S2. Assemble the first steel beam segment on the steel beam assembly bracket (3); S3. Continue to assemble the subsequent steel beam segments on the steel beam assembly bracket (3), and at the same time assemble the first arch rib (6) on the arch rib assembly bracket (4) and install the front guide beam (7). S4. The assembled steel beam segment and the first arch rib (6) are pushed out of the pre-set assembly area by a first predetermined distance. S5. On the steel beam assembly bracket (3) and arch rib assembly bracket (4) that are empty in the preset assembly area, continue to assemble the next steel beam segment and the next arch rib (6), and install the hanger (9) between the already in place arch rib (6) segments. The hanger (9) is in a non-tensioned state. S6. The assembly consisting of all assembled segments of steel beams and arch ribs (6) is pushed out of the pre-set assembly area by a second predetermined distance. S7. Repeat steps S5 and S6 to perform segment assembly, installation of hangers (9) and overall jacking until the steel beam (5) and arch rib (6) are fully assembled and the guide beam (8) is installed. S8. Simultaneously push the complete steel beam (5) and arch rib (6) assembly to the designed bridge position, remove the front guide beam (7) and rear guide beam (8), and lower the beam; S9. Tension all the hangers (9), dismantle the temporary pier support (2), steel beam assembly support (3) and arch rib assembly support (4) to complete the construction.

2. The method of circulating push construction of a through arch bridge according to claim 1, wherein, The jacking operations in steps S4, S6 and S8 are carried out using a walking jacking device.

3. The method of circulating push construction of a through arch bridge according to claim 2, wherein, The walking-type jacking device is arranged on top of the permanent pier (1), the temporary pier support (2) and the steel beam assembly support (3).

4. The method of circulating push construction of a through arch bridge according to claim 1, wherein The jacking operations in steps S4, S6 and S8 are carried out using a traction-type jacking device.

5. The method of circulating push construction of a through arch bridge according to claim 4, wherein The traction-type jacking device includes: a slide rail set on the top of the pier (1), the temporary pier support (2) and the steel beam assembly support (3), and a traction jack; the traction jack is set on the abutment (11), which is part of the pier (1); the traction jack is used to pull the steel beam and the arch rib assembly along the slide rail.

6. The method of circulating push construction of a through arch bridge according to claim 1, wherein During the cyclic construction process in step S7, all steel beam segments are assembled at the same position on the fixed steel beam assembly bracket (3), and all arch rib segments are assembled at the same position on the fixed arch rib assembly bracket (4).

7. A through arch bridge steel beam for use in the construction method according to any one of claims 1 to 6, characterized in that The steel beam (5) is designed to be assembled from multiple segments in a fixed position and temporarily connected to the arch ribs (6) of the corresponding segments during the assembly process to form a combined body that can be pushed in stages.

8. A through arch bridge steel beam according to claim 7, characterised in that The front end and rear end of the steel beam (5) are respectively provided with a detachable front guide beam (7) and a rear guide beam (8).

9. A through arch bridge built by the method according to any one of claims 1 to 6, characterized in that, This includes the steel beam (5), arch rib (6), suspender (9) connecting the two, and pier (1) constructed by the method described above.

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