Full-stress incremental launching construction method for large-span basket tied arch bridge

Abstract

The invention discloses a full-stress incremental launching construction method for a large-span basket tied arch bridge, which comprises the following steps: S1, completing the assembly of a main beam of the arch bridge, erecting an arch rib assembly bracket on the assembled main beam, and assembling arch ribs until the arch ribs are closed; s2, the arch rib assembling support is dismantled, so that the main beam is separated from the assembling support; s3, arch rib tie bars are symmetrically installed before pushing for primary tensioning, secondary cable adjustment is executed after the decoration section is installed to reach the designed cable force, and the finished bridge cable force and the line shape are made to be matched with the design state; s4, a locking device is installed, and the stress and the linear state of the arch rib and the beam are locked; s5, installing pushing temporary piers, pushing the whole arch bridge to a designed position, and then falling the bridge to a permanent support; and S6, the temporary piers and the locking devices are dismantled, and basket tied-arch bridge forming construction is completed. The construction method has the advantages of improving the construction efficiency of the basket tied arch bridge, reducing the construction difficulty, improving the durability of the bridge and reducing the function influence of an inland river channel.

Description

Technical Field

[0001] The present invention belongs to the field of civil engineering bridge construction. More specifically, the present invention relates to a full-stress jacking construction method for a long-span basket-shaped tied-arch bridge. Background Art

[0002] The water surface of inland rivers in China is relatively narrow, and the basket-shaped tied-arch bridge is usually selected as the bridge type for building bridges on rivers. Especially in urban areas, the aesthetic value of the basket-shaped tied-arch bridge is more prominent. The main functions of inland rivers are navigation and flood discharge. The conventional methods for constructing basket-shaped tied-arch bridges are the support + cable hoisting method, the support + crawler crane hoisting method, etc. The above two methods both set up full-span steel pipe beam supports in inland rivers, which occupy a large amount of the river channel and have a great impact on the functions of inland river navigation and flood discharge. The construction period is long, and it cannot meet the current need to relieve the large-scale urban traffic. Moreover, the construction measures are large and uneconomical. Based on the above problems, the current technology of off-site production + jacking in place is widely used, that is, an arch bridge assembly support is set up in the approach bridge area, and the arch bridge is longitudinally jacked to the designed position, and finally the tie rod and the decoration section are constructed. This method still has the following disadvantages: the tie rod and the decoration section are installed or a hoisting device is set up on the trestle for hoisting, or a hoisting device is set up on the bridge deck for hoisting. Among them, the construction of the trestle also affects the river channel function. Hoisting on the bridge deck requires waiting until the approach bridge in the area where the arch bridge is assembled is completed, and then the access channel for the hoisting device on the bridge can be established. Moreover, the hoisting device on the bridge deck exists as an additional load, which affects the tensioning force of the tie rod and the bridge alignment. Therefore, the designed in-place cable force and alignment of the bridge cannot be matched, which further affects the structural durability and the difficulty of operation and maintenance.

[0003] Therefore, to further improve the construction process to ensure that the in-place cable force and alignment of the basket-shaped arch bridge match the design, a full-stress jacking construction method for a long-span basket-shaped tied-arch bridge is proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide a full-stress jacking construction method for a long-span basket-shaped tied-arch bridge, which improves the construction efficiency of the basket-shaped tied-arch bridge, reduces the construction difficulty, improves the bridge durability, and reduces the impact on the functions of inland river channels.

[0005] The technical solution adopted by the present invention to solve this technical problem is: a full-stress jacking construction method for a long-span basket-shaped tied-arch bridge, including: S1. Complete the assembly of the main beam of the arch bridge. On the assembled main beam, set up an arch rib assembly support and assemble the arch rib until the arch rib is closed. S2. Remove the arch rib assembly support to separate the main beam from the assembly support. S3. Symmetrically install the arch rib tie rod before jacking for the first tensioning. After installing the decoration section, perform the second cable adjustment to the designed cable force to make the in-place cable force and alignment of the bridge match the designed state. S4. Install the locking device to lock the stress and linear state of the arch rib and the beam. S5. Install the incremental launching temporary piers, and after launching the whole arch bridge to the designed position, lower the beam onto the permanent bearings. S6. Demolish the temporary piers and the locking device to complete the construction of the basket - type tied - arch bridge.

[0006] As a further solution of the present invention: The assembly of the main beam of the arch bridge specifically includes: Erect the assembly support for the main beam of the arch bridge in the approach bridge area, and add rigid fixing piers to the assembly support. The rigid fixing piers are arranged at the ends of the calculated span of the arch bridge to simulate the position of the main piers; the top of the rigid fixing piers is provided with adjustable - height bearings for accurately matching the preset linear shape of the main beam during the assembly stage.

[0007] Use a lifting device to assemble the main beam of the arch bridge on the main beam assembly support.

[0008] As a further solution of the present invention: Before the assembly of the main beam of the arch bridge in S1, complete the construction of the main bridge pile foundation and the lower structure, and complete the construction of the approach bridge pile foundation and the lower structure. Among them, the height of the pier column is designed not to affect the assembly of the arch bridge.

[0009] As a further solution of the present invention: When demolishing the arch rib assembly support, simultaneously unload the assembly support of the rigid fixing piers to separate the main beam from the assembly support.

[0010] As a further solution of the present invention: The specific steps of the secondary cable adjustment in S3 include: After the installation of the decorative section is completed, use sensors to monitor the cable force and the bridge linear shape in real - time, use hydraulic tensioning equipment to gradually adjust the cable force to the designed value, and simultaneously correct the bridge linear error to ensure that the structural stress state during the incremental launching process is consistent with the design.

[0011] As a further solution of the present invention: The locking device in S4 is a rigid steel structure connecting piece, and its two ends are respectively welded and fixed to the arch rib and the main beam, and is used to maintain the relative position and stress distribution of the arch rib and the main beam during the incremental launching process.

[0012] As a further solution of the present invention: The installation position of the locking device is determined according to the finite - element model calculation, avoiding the maximum stress area during the incremental launching process, and its quantity is symmetrically distributed along the axis of the arch rib.

[0013] As a further solution of the present invention: In S5, during the incremental launching process, a multi - point synchronous incremental launching control system is adopted to monitor the displacement deviation of each incremental launching point in real - time, and adjust the incremental launching speed through a hydraulic deviation - correcting device to ensure that the overall linear error of the arch bridge is less than 10 mm.

[0014] As a further solution of the present invention: in step S3, after the primary tensioning is completed, a temporary support structure is provided between the arch rib and the main girder to share the local load during the jacking process, and the temporary support structure is removed after the secondary cable adjustment; The cable force adjustment accuracy of the secondary cable adjustment is controlled within ±2%, and the bridge alignment error is controlled within ±5 mm.

[0015] As a further solution of the present invention: it further includes S7, removing the arch bridge assembly brackets in the approach bridge area, constructing the remaining pier caps and superstructures of the approach bridge by conventional processes, and completing the line connection.

[0016] The present invention has at least the following beneficial effects: The present invention manufactures at a position outside the arch bridge line, simulates the boundary conditions of the completed bridge, installs the tie rod and tensions it, installs the decorative section, adjusts the cables to the designed cable force for the second time, then locks the arch rib and the main girder, jacks the arch bridge into place, and finally removes the locking device between the arch rib and the main girder to complete the bridge. It shortens the influence time and scope of the river channel function, ensures the coincidence of the construction completed bridge stress and the design stress, and improves the structural durability. Moreover, the present invention is applicable to the construction of long-span basket-shaped tied arch bridges. The invention has a simple, reliable and convenient operation structure, speeds up the installation speed, and standardizes, regularizes and secures the construction of the same type of cable-stayed bridge.

[0017] This application details the cable adjustment accuracy, the structure of the locking device and the installation requirements, highlighting the precise control of the completed bridge stress and alignment in this application, and solving the problem of cable force deviation caused by the separation of construction processes in the prior art.

[0018] Safety: It transforms the water operation into land operation. Most of the work is carried out on land, with a fast construction speed, high accuracy and high safety performance.

[0019] Economy: This method avoids the investment in water trestles and water equipment, can save equipment investment, and can effectively reduce the construction cost.

[0020] Short construction period: Multiple overlapping construction processes are carried out, the construction organization is optimized, and the construction period is shortened.

[0021] Wide application range: It can be used for the construction of the same type of arch bridges.

[0022] Other advantages, objectives and features of the present invention will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the basket-shaped tied arch bridge type; Figure 2 It is a side view of the basket-shaped tied arch bridge type; Figure 3 It is a schematic diagram of the temporary support structure of the basket-shaped tied arch bridge; Figure 4 It is a schematic diagram of the state before the jacking of the basket - type tied - arch bridge. Figure 5 It is a schematic diagram of Step 1. Figure 6 It is a schematic diagram of Step 2. Figure 7 It is a schematic diagram of Step 3. Figure 8 It is a schematic diagram of Step 4. Figure 9 It is a schematic diagram of Step 5. Figure 10 It is a schematic diagram of Step 6. Figure 11 It is a schematic diagram of Step 7. Figure 12 It is a schematic diagram of installing the jacking temporary pier in the river channel in Step 8. Figure 13 It is a schematic diagram of jacking in Step 8. Figure 14 It is a schematic diagram of lowering the beam to the permanent bearing of the main pier in Step 8. Figure 15 It is a schematic diagram of Step 9. Figure 16 It is a schematic diagram of Step 10.

[0024] Among them, 1 - basket - type tied - arch bridge, 1.1 - main beam, 1.2 - arch rib, 1.3 - tie rod, 1.4 - decorative section, 2.1 - main beam assembly support, 2.2 - jacking temporary pier, 2.3 - rigid fixed pier, 2.4 - arch rib assembly support, 2.5 - jacking guiding beam, 3 - locking device. Detailed implementation manners

[0025] The present invention will be described in detail and completely below with reference to the accompanying drawings. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. Before describing the present invention with reference to the accompanying drawings, it should be particularly noted that: the technical solutions and technical features provided in each part including the following descriptions can be combined with each other without conflict.

[0026] In addition, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, rather than all of the embodiments. Therefore, all other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts should fall within the scope of protection of the present invention.

[0027] The full-stress incremental launching construction method of a long-span basket-shaped tied-arch bridge in this application can be adopted for both inland river arch bridges, inland river bridges or cross-valley arch bridges. The following further elaborates on the present invention in conjunction with the attached drawings and embodiments, and the specific implementation process is as follows: As Figure 1 shown, the present invention provides a full-stress incremental launching construction method for a long-span basket-shaped tied-arch bridge, including: Step 1: Construct the main bridge pile foundation and lower structure of the basket-shaped tied-arch bridge 1 by conventional techniques, construct the approach bridge pile foundation and lower structure, and the pier height does not affect the assembly of the arch bridge. Step 2: Set up the arch bridge main girder assembly support 2.1 in the approach bridge area, add a rigid fixed pier 2.3 to the assembly support, and the rigid fixed pier 2.3 is arranged at the end of the calculated span of the arch bridge to simulate the position of the main pier.

[0028] Step 3: Use a self-propelled lifting device. The lifting device stands on both sides of the main girder assembly support 2.1, the incremental launching temporary pier 2.2 and the rigid fixed pier 2.3, and assemble the arch bridge main girder 1.1 on the main girder assembly support 2.1.

[0029] Step 4: On the assembled main girder 1.1, set up the arch rib assembly support 2.4 for assembling the arch rib 1.2, and sequentially assemble the arch rib 1.2 in a bracing manner until it is closed.

[0030] Step 5: After the arch rib 1.2 is closed, remove the arch rib assembly support 2.4, and simultaneously unload the assembly support of the rigid fixed pier to disconnect the main girder 1.1 from the assembly support.

[0031] Step 6: Symmetrically install the arch rib tie rod 1.3 and conduct a primary tensioning. After all the tie rods 1.3 are installed, install the decorative section 1.4, and finally conduct a secondary tensioning of the tie rod 1.3 to adjust the cable force of the tie rod 1.3 to match the design. The specific steps include: After the installation of the decorative section is completed, the cable force and the bridge alignment are monitored in real time through sensors, and a hydraulic tensioning device is used to gradually adjust the cable force to the design value, and the bridge alignment error is corrected synchronously to ensure that the structural stress state during the incremental launching process is consistent with the design.

[0032] Step 7: Install the locking device 3 for the arch rib and the main girder to lock the stress and alignment states of the arch rib 1.2 and the main girder 1.1, and install the incremental launching guiding girder 2.5 for incremental launching.

[0033] Step 8: While operating in Step 7, install the incremental launching temporary pier 2.2 in the river channel, launch the arch bridge and the locking device 3 to the design position, and lower the beam to the permanent bearing of the main pier.

[0034] Step 9: Remove the incremental launching temporary pier 2.2 in the river channel, remove the incremental launching guiding girder 2.5, and symmetrically remove the locking device in sequence, and the basket-shaped tied-arch bridge is completed.

[0035] Step Ten: Demolish the main girder erection brackets 2.1 and the incremental launching temporary piers 2.2 in the approach bridge area, and construct the remaining pier caps and superstructures of the approach bridge by conventional techniques to complete the line connection.

[0036] This technical solution may also include the following technical details to better achieve the technical effects: In S4, the locking device 3 is a rigid steel structure connecting piece, and its two ends are respectively welded and fixed to the arch rib 1.2 and the main girder 1.1, and is used to maintain the relative position and stress distribution between the arch rib and the main girder during the incremental launching process.

[0037] This technical solution may also include the following technical details to better achieve the technical effects: The installation position of the locking device 3 is determined according to the calculation of the finite element model, avoiding the maximum stress area during the incremental launching process, and its quantity is symmetrically distributed along the axis of the arch rib.

[0038] This technical solution may also include the following technical details to better achieve the technical effects: In S5, a multi-point synchronous incremental launching control system is adopted during the incremental launching process to real-time monitor the displacement deviation of each incremental launching point, and adjust the incremental launching speed through the hydraulic deviation correction device to ensure that the overall linear error of the arch bridge is less than 10 mm.

[0039] This technical solution may also include the following technical details to better achieve the technical effects: In S3, after the first tensioning is completed, a temporary support structure is set between the arch rib 1.2 and the main girder 1.1 to share the local load during the incremental launching process, and the temporary support structure is demolished after the second cable adjustment; The cable force adjustment accuracy of the second cable adjustment is controlled within ±2%, and the bridge linear error is controlled within ±5 mm.

[0040] This technical solution may also include the following technical details to better achieve the technical effects: It also includes S7, demolish the arch bridge erection brackets in the approach bridge area, construct the remaining pier caps and superstructures of the approach bridge, and complete the line connection.

[0041] Although the embodiments of the present invention have been disclosed as above, it is not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the embodiments shown and described here.

Claims

1. A full stress jacking construction method for a large span basket-handled tied arch bridge, characterized in that: include: S1. Complete the assembly of the main beam of the arch bridge, set up the arch rib assembly bracket on the assembled main beam, and assemble the arch ribs until the arch ribs are connected; S2. Remove the arch rib assembly bracket to separate the main beam from the assembly bracket; S3. Before jacking, the arch rib tie rods are symmetrically installed for primary tensioning. After the decorative section is installed, the cables are adjusted to the designed cable tension for a secondary time, so that the cable tension and line shape of the completed bridge are consistent with the designed state. S4. Install a locking device to lock the stress and linear state of the arch rib and beam; S5. Install the temporary piers, push the arch bridge to the designed position, and then drop the beams to the permanent supports; S6. Remove the temporary piers and locking devices to complete the construction of the basket-lift tied arch bridge.

2. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1, characterized in that: The arch bridge main beam assembly specifically includes: An arch bridge main beam assembly bracket is set up in the approach bridge area, and a rigid fixed pier is added to the assembly bracket. The rigid fixed pier is set at the end of the calculated span of the arch bridge to simulate the main pier position; The arch bridge main beam is assembled on the main beam assembly bracket by using lifting equipment.

3. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1 or 2, characterized in that: Before assembling the main beam of the arch bridge in S1, the pile foundation and substructure of the main bridge are completed, and the pile foundation and substructure of the approach bridge are completed. The pier height is designed not to affect the assembly of the arch bridge.

4. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 2, characterized in that: When dismantling the arch rib assembly bracket, the assembly bracket of the rigid fixed pier is unloaded simultaneously to separate the main beam from the assembly bracket.

5. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1, characterized in that: The specific steps of the secondary adjustment in S3 include: After the decoration section is installed, sensors are used to monitor the cable tension and bridge line shape in real time. Hydraulic tensioning equipment is used to adjust the cable tension to the design value step by step, and the bridge line shape error is corrected simultaneously to ensure that the structural stress state during the jacking process is consistent with the design.

6. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1, characterized in that: The locking device in S4 is a rigid steel structure connector, both ends of which are respectively welded and fixed to the arch rib and the main beam, and is used to maintain the relative position and stress distribution of the arch rib and the main beam during the jacking process.

7. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 6, characterized in that: The installation position of the locking device is determined according to finite element model calculation, avoiding the maximum stress area during the jacking process, and the number of the locking device is symmetrically distributed along the arch rib axis.

8. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1, characterized in that: In S5, a multi-point synchronous pushing control system is used during the pushing process to monitor the displacement deviation of each pushing point in real time, and adjust the pushing speed through a hydraulic correction device to ensure that the overall linear error of the arch bridge is less than 10 mm.

9. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 1, characterized in that: In S3, after the primary tensioning is completed, a temporary support structure is set between the arch rib and the main beam to share the local load during the jacking process, and the temporary support structure is removed after the secondary cable adjustment; The cable force adjustment accuracy of the secondary cable adjustment is controlled within ±2%, and the bridge linear error is controlled within ±5mm.

10. The full stress jacking construction method for a long-span basket-handled tied arch bridge according to claim 3, characterized in that: It also includes S7, dismantling the arch bridge assembly bracket in the approach bridge area, constructing the remaining piers, cap beams and superstructure of the approach bridge, and completing the line connection.

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