Construction method of double-hole concrete arch bridge arch

Abstract

The application discloses a double-hole concrete arch bridge arch ring construction method, which comprises the following steps: S1, temporary support is erected, an arch frame is assembled, a rotating disc is installed at a middle arch support, vertical rotating support and a first vertical rotating cable are installed, and first vertical rotating construction is carried out; S2, after the first vertical rotating construction is completed, a plurality of second vertical rotating cables are used to connect the arch frame, second vertical rotating construction is carried out, and the arch frame is vertically rotated to a design elevation position; S3, the rotating disc is rotated, the arch frame is horizontally rotated along with the rotating disc, and the arch frame is stopped rotating after being integrally rotated to a design axis; S4, the remaining part of the arch frame on the right side is assembled and closed; S5, the remaining part of the arch frame on the left side is assembled by using the same method in step S4; and S6, the cable, back cable and cable tower are removed, a concrete arch ring is poured, the concrete arch ring construction is completed, then a bridge pier is poured, and then an upper structure of the bridge is constructed. The application reduces high-altitude assembling and welding workload, shortens the construction period, and simplifies the construction. The arch ring is poured in three rings, and the steel frame consumption is reduced.

Description

Technical Field

[0001] This invention relates to the field of construction of multi-span reinforced concrete arch bridges, and more specifically to a construction method for the arch ring of a double-span concrete arch bridge. Background Technology

[0002] In the construction of reinforced concrete arch bridges, steel arch frames are generally used as the support system for the main structure construction. The steel arch frames are assembled in stages using cable hoists or in situ using scaffolding. Both methods require workers to operate at heights, posing significant safety risks and making it impossible to guarantee the quality of the steel arch frame assembly.

[0003] Many arch bridges are located in deep mountain valleys or in areas with rapid water flow. Two-span arch bridges with equal spans are generally constructed using in-situ support assembly or cable-stayed construction. Cable-stayed construction is costly, and the support method is extremely dangerous in such terrains. In order to reduce construction costs and safety risks associated with ultra-high supports, it is necessary to find a low-cost method with relatively low safety risks.

[0004] Some existing concrete arches are cast in one go, which places higher demands on the load-bearing capacity of the steel frame, resulting in a huge amount of steel frame usage. Summary of the Invention

[0005] To overcome the above-mentioned defects of the prior art, the present invention provides a construction method for the arch ring of a double-arch concrete bridge.

[0006] The technical solution of this invention is as follows:

[0007] The construction method for the arch ring of a double-span concrete arch bridge includes the following steps:

[0008] S1. Select a central location in the surveyed terrain and install the intermediate arch seat. Rotate and install a turntable on the intermediate arch seat. Rotate and install the inner arch frame on both sides of the turntable. Vertically set the rotating shaft on the turntable. Connect the two ends of the arch frame to the top of the rotating shaft through the first vertical rotation cable. Then carry out the first vertical rotation construction to close the ends of the arch frame.

[0009] S2. After the first vertical rotation is completed, multiple second vertical rotation cables are used to connect the arch frame for the second vertical rotation, so that the arch frame is rotated to the design elevation position.

[0010] S3. Rotate the turntable, and the arch frame will rotate horizontally accordingly. Stop rotating after the whole structure has rotated to the design axis.

[0011] S4. The remaining arch frame on the right side is assembled and closed.

[0012] Assemble the remaining arch frame, install the right arch seat on the side of the mountain, and rotate the lower end of the remaining arch frame to connect with the right arch seat. The other end of the remaining arch frame is slowly lowered through the fastening cable and joined with the corresponding arch frame.

[0013] S5. Assemble the remaining arch frame on the left side using the same method as in step S4.

[0014] S6. After the steel arch frame is assembled, remove the tie cables, back cables, and towers, and pre-stress the steel arch ring. Then, erect the formwork, tie the reinforcing bars, and pour the concrete arch ring.

[0015] S7. Each concrete arch is divided into five sections and is poured in three rings. The three-ring pouring method is to pour the bottom plate, web plate and top plate in separate rings.

[0016] First, pour the first ring, which is the arch box of segments 1, 3, 5, 6, 8, and 10 of the base plate; after the concrete strength of segments 1, 3, 5, 6, 8, and 10 of the first ring reaches the design strength, pour segments 2, 4, 7, and 9 of the arch box symmetrically. At this time, the concrete of the first ring arch box will close; then repeat the above steps to pour the concrete of the second and third rings.

[0017] S8. After the concrete arch ring construction is completed, the bridge piers are poured symmetrically from the arch foot to the arch crown, and then the superstructure of the bridge is constructed.

[0018] Before step S1, there is also the following step: first, erect a low temporary support frame and assemble part of the steel arch frame in sections.

[0019] In step S2, after the arch frame is vertically rotated to the design elevation, it is re-measured to ensure accuracy.

[0020] In step S3, according to the design requirements, the rotation parameter is: 88° counterclockwise rotation.

[0021] After step S3 is completed, the turntable hinge is poured after verifying the arch frame axis, and the concrete around the arch seat is backfilled.

[0022] In step S4, part of the arch frame is assembled along the mountainside, and the remaining part is assembled on a temporary support.

[0023] In step S5: Some arch frames can be assembled vertically along the transition pier by setting fixed supports vertically.

[0024] In steps S4 and S5, the remaining arch frame is connected to a corresponding planar cable. This is because in the initial process, the arch frame does not yet have the force to rotate downwards, and the planar cable is used to pull the corresponding arch frame downwards.

[0025] The technical effects and advantages of this invention are as follows:

[0026] 1. This construction method reduces the amount of high-altitude assembly and welding work, shortens the construction period, and simplifies the construction process.

[0027] 2. It improves the efficiency of on-site arch frame assembly and welding, facilitates the control of welding quality, reduces the amount of direct assembly required, lowers the requirements for lifting equipment, and minimizes construction safety risks.

[0028] 3. When pouring the arch ring, it is divided into three rings: the bottom plate, the web plate, and the top plate are poured in rings. In this way, after the first ring is poured, the properties of the concrete in the first ring can be used to share part of the stress, reducing the amount of steel frame used. Attached Figure Description

[0029] Figure 1 A schematic diagram showing the erection of the support frame and the assembly of the arch frame at arch seat No. 10.

[0030] Figure 2 A schematic diagram of the vertical rotation of the arch frame at arch seat No. 10;

[0031] Figure 3 This is a schematic diagram of the arch frame rotating counterclockwise.

[0032] Figure 4 A schematic diagram of the arch frame assembly at arch seats 9 and 11;

[0033] Figure 5 A schematic diagram of the vertical rotation of the arch frame at arch seats 9 and 11;

[0034] Figure 6 A schematic diagram showing the steel arch ring assembly completed, the cable ties attached, the back cables installed, and the tower dismantled.

[0035] Figure 7 This is a schematic diagram showing the concrete arch segments 1, 3, 5, 6, 8, and 10 of the first ring after pouring.

[0036] Figure 8 This is a schematic diagram showing the concrete arch segments 2, 4, 7, and 9 of the first ring after pouring.

[0037] Figure 9 This is a schematic diagram of the superstructure after construction. Detailed Implementation

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and 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.

[0039] This method leverages the terrain advantage at an 88° angle to the bridge site, constructing low temporary supports to assemble the steel arch frame in segments. A steel arch that can rotate around its base is then installed at the arch abutment. After assembly, the arch frame is transferred to the design elevation using a combination of vertical and horizontal rotation before being joined together. The arch axis is then re-measured, and the main arch structure construction proceeds. The location of arch abutment No. 10 was selected during the preliminary survey and is suitable for W-shaped terrain.

[0040] The specific implementation methods and features are described below:

[0041] Step 1: Erect temporary support 1, assemble arch frame 2, install turntable 3 at the middle arch seat (arch seat 10), vertically install rotating shaft 31 on the turntable, install vertical rotation support 4 and first vertical rotation fastening cable 5, and carry out the first vertical rotation construction. Figure 1 As shown.

[0042] Step Two: After the first vertical rotation is completed, multiple second vertical rotation cables (6) are used to connect the arch frame. The second vertical rotation is then performed at arch seat No. 10. After reaching the design elevation, a re-measurement is conducted to ensure the arch frame is in place. Figure 2 As shown.

[0043] Step 3: The steel arch frame of arch seat No. 10 is vertically rotated a second time to the design elevation and then rotated 88° counterclockwise to the design axis. After verifying the arch frame axis, the turntable is poured to seal the hinge, and the concrete around the arch seat is backfilled. For example... Figure 3 As shown.

[0044] Step Four: The steel arch frame of the right arch seat (arch seat No. 11) is assembled along the mountainside, and the remaining part is assembled on the support frame. Specifically: the right arch seat is installed on the side of the mountainside, the lower end of the remaining arch frame is rotatably connected to the right arch seat, and the other end of the remaining arch frame is slowly lowered through the fastener 7, aligning and closing with the corresponding arch frame; the steel arch frame of the left arch seat (arch seat No. 9) can be vertically assembled along the transition pier by setting up fixed supports. Figure 4 As shown.

[0045] Step 5: After the steel arch frame of arch seat No. 11 is assembled, it undergoes a third vertical rotation, rotating counterclockwise until it aligns with the designed arch axis. Simultaneously, after the steel arch frame of arch seat No. 9 is assembled, it is rotated clockwise to the designed arch axis and then closed. (The rest of the text is incomplete and likely refers to a different step.) Figure 5 As shown.

[0046] Step Six: After the steel arch frame is assembled, remove the tie cables, back cables, and pylons, and pre-stress the steel arch ring. Then, erect the formwork, tie the reinforcing bars, and pour the concrete arch ring. Figure 6 As shown.

[0047] Step Seven: Each concrete arch ring is poured in five sections and three rings (bottom slab, web slab, and top slab). The first ring (80cm high) of concrete for the bottom slab of arch box sections 1, 3, 5, 6, 8, and 10 is poured symmetrically. After the concrete strength of sections 1, 3, 5, 6, 8, and 10 reaches the design strength, the first ring (80cm high) of concrete for sections 2, 4, 7, and 9 is poured symmetrically, thus closing the first ring of the arch box concrete. Then, the above steps are repeated to pour the second and third rings of concrete. Figure 7 and Figure 8 As shown.

[0048] Step 8: After the concrete arch ring construction is completed, the bridge piers are poured symmetrically from the arch foot to the arch crown, followed by the construction of the bridge superstructure. (For example...) Figure 9 As shown.

[0049] Furthermore, in steps S4 and S5, the remaining part of the arch frame is connected to the corresponding planar cable 8, because in the initial process the arch frame does not yet have the force to rotate downwards, the planar cable is used to pull the corresponding lower part of the arch frame.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for constructing a double-hole concrete arch bridge arch ring, characterized in that, Includes the following steps: S1. Select a central location in the surveyed terrain and install the intermediate arch seat. Rotate and install a turntable on the intermediate arch seat. Rotate and install the turntable on both sides and the inner side of the arch frame. Vertically set the rotating shaft on the turntable. Connect the top of the rotating shaft to both ends of the arch frame through the first vertical rotation cable. Then carry out the first vertical rotation construction to close the ends of the arch frame. S2. After the first vertical rotation is completed, multiple second vertical rotation cables are used to connect the arch frame for the second vertical rotation, so that the arch frame is rotated to the design elevation position. S3. Rotate the turntable, and the arch frame will rotate horizontally accordingly. Stop rotating after the whole structure has rotated to the design axis. S4. Assemble and close the remaining arch frame on the right side. Install the right arch seat on the side of the mountain. The lower end of the remaining arch frame is rotatably connected to the right arch seat. The other end of the remaining arch frame is slowly lowered through the fastening cable and aligned with the corresponding arch frame. S5. Assemble the remaining arch frame on the left side using the same method as in step S4. S6. After the steel arch frame is assembled, remove the tie cables, back cables, and cable towers, and pre-stress the steel arch ring. Then, formwork is erected, steel bars are tied, and concrete arch rings are poured. S7. Each concrete arch is divided into five sections and is poured in three rings. The three-ring pouring method is to pour the bottom plate, web plate and top plate in separate rings. First, pour the first ring, which is the arch box of segments 1, 3, 5, 6, 8, and 10 of the base plate; after the concrete strength of segments 1, 3, 5, 6, 8, and 10 of the first ring reaches the design strength, pour segments 2, 4, 7, and 9 of the arch box symmetrically. At this time, the concrete of the first ring arch box will close; then repeat the above steps to pour the concrete of the second and third rings. S8. After the concrete arch ring construction is completed, the bridge piers are poured symmetrically from the arch foot to the arch crown, and then the superstructure of the bridge is constructed. In step S4, some arch frames are assembled along the mountainside, and the remaining parts are assembled on temporary supports; in step S5, some arch frames can be vertically assembled along the transition pier by setting fixed supports vertically; in steps S4 and S5, the remaining arch frames are connected with corresponding planar cables, because in the initial process, the arch frames do not have the force to rotate downwards, and the planar cables are used to pull the corresponding arch frames to rotate downwards.

2. The method according to claim 1, wherein: Before step S1, there is also the following steps: first, erect a low temporary support frame and then assemble part of the steel arch frame in sections.

3. The method of claim 1, wherein: In step S2, after the arch frame is vertically rotated to the design elevation, it is re-measured to ensure accuracy.

4. The method of claim 1, wherein: In step S3, according to the design requirements, the rotation parameter is: 88° counterclockwise rotation.

5. The method of claim 1, wherein: After step S3 is completed, the turntable hinge is poured after verifying the arch frame axis, and the concrete around the arch seat is backfilled.

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