A fast construction method of a special-shaped double-tower double-cable-plane cable-stayed bridge

Abstract

The application provides a special-shaped double-tower double-cable-plane cable-stayed bridge fast construction method, which comprises the following steps: temporary support system construction, bridge main body construction, lattice column construction, cable tower body construction, cable tower concrete construction and hoisting cable segmented tensioning. The bridge stress system is good, the construction is fast, safe and environment-friendly.

Description

Technical Field

[0001] This invention relates to the field of cable-stayed bridge construction technology, specifically a rapid construction method for an irregular double-tower double-cable-stayed bridge. Background Technology

[0002] Compared to other types of urban bridges, pedestrian bridges, due to differences in their environment, users, structural span, and load-bearing requirements, require landscape design that relies on unique aesthetic creation and diverse bridge shapes to better express the spatial charm of the integration of art and structure.

[0003] The conventional construction method for a double-tower, double-cable-stayed bridge is to construct the towers first, then the beams, in segments, with symmetrical tensioning. However, for irregular double-tower, double-cable-stayed bridges, the bridge space is asymmetrical, the stress system is complex, stress and strain control is difficult, construction progress is slow, operation methods are complex, construction costs are high, and resources are scarce. Traditional construction methods have significant limitations in construction procedures, and stress and strain control for the main towers and other structures is difficult. Therefore, conventional methods are not suitable for construction, regardless of the construction methods, construction sequence, or construction equipment. Summary of the Invention

[0004] In view of the above-mentioned prior art, the present invention proposes a rapid construction method for a non-standard double-tower double-cable-stayed bridge. This method has a short river channel occupation time, a good bridge stress system, and is fast, safe and environmentally friendly.

[0005] This invention provides a rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge, comprising the following steps:

[0006] S1. Construction of temporary support system: Calculate the spatial center of gravity of the main body of the bridge and several support points after the suspension cables are tensioned. Construct an underwater operating platform on the river surface. Drive steel pipe piles at the support points. After the steel pipe piles are driven into place, install a head plate at the top of the steel pipe piles. Install double H-beams at the top of the head plate. Install a crossbeam at the top of the double H-beams. Install several main ribs along the transverse direction at the top of the crossbeams. Weld the lower ends of the main ribs to the top of the crossbeams with steel plates.

[0007] S2. Bridge main body construction: Steel box girder segments are hoisted in sequence, welding and process evaluation are carried out between steel box girder segments, and after passing the evaluation, the whole bridge main body is hoisted and lowered onto the main rib. The upper end of the main rib is spot welded to the bottom perimeter of the steel box girder through steel plates.

[0008] S3. Construction of lattice columns: Two sets of lattice columns are installed at the upper end of the main body of the bridge as temporary supports for the tower body. An arc-shaped support plate is set on the top of the lattice columns. The arc-shaped support plate is tightly integrated with the tower. A rubber pad is set between the two to protect the tower wall.

[0009] S4. Tower construction: The tower body is pre-assembled and prepared for hoisting after welding inspection. Before the tower body is installed and fixed, a tower base positioning frame is welded on the tower body platform to adjust the left and right positions and accurately position the tower body. During hoisting, the top of the tower body is temporarily supported by the lattice column.

[0010] S5. Concrete construction of the tower: The mix design is carried out in advance to prepare a suitable micro-expansion self-compacting concrete, which is pumped in using the inclined chute pre-reserved on the tower body during the pumping process.

[0011] S6. Segmented tensioning of suspenders: After the concrete of the tower reaches the design strength, the suspenders are tensioned segment by segment.

[0012] Preferably, in S1, several 2cm thick stiffening plates are provided between the flange plates located at the pile head position on the double-section H-beam, with a spacing of 250mm, and several 2cm thick stiffening plates are provided between the flange plates located at other positions, with a spacing of 500mm.

[0013] Preferably, in S1, a figure-eight brace is set on both sides of the double H-beam to form a stable temporary support system. The figure-eight brace is made of round steel pipe with a diameter of 250mm and a wall thickness of 7mm.

[0014] Preferably, in S3, during the use of the lattice column, a guy rope is installed in each of the four directions at two-thirds of its height, and the guy rope is bolted to the pre-welded lifting lugs on the steel box girder.

[0015] Preferably, in S3, the arc-shaped support plate is made of steel plate bent into a semi-circular arc shape.

[0016] Preferably, in S4, the tower base positioning frame adopts a double-layer annular positioning frame. The lower positioning ring adopts a serrated positioning ring with a diameter larger than the diameter of the tower base, and the upper positioning ring adopts an openable positioning ring. The openable positioning ring is perpendicular to the tower axis. The inner diameter of the openable positioning ring is larger than the tower diameter, and the outer diameter is larger than the inner diameter of the ring. Trapezoidal blocks are rotatably installed on both sides of the serrated positioning ring, and the upper end of the trapezoidal blocks is fixedly connected to the openable positioning ring.

[0017] Preferably, in S5, several arc-shaped protrusions are arranged laterally in the inclined chute to reduce the flow velocity.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The construction method of this invention can meet the requirements of safety and quality while maximizing the on-site construction progress, and is especially suitable for areas with high requirements for river flood season.

[0020] 2. The temporary underwater steel pipe pile support in this invention can effectively serve the installation of the main beam on site. The support system is flexible, simplifies the stress system, is easy to drive and pull, has good quality control effect, and has a small water-blocking area in the river channel.

[0021] 3. The temporary lattice support structure of the independent cable tower in this invention requires less material, is easy to dismantle later, has lower costs, and has a higher utilization rate of support materials. At the same time, the use of the arc-shaped support plate at the top of the lattice column can achieve accurate spatial positioning, effectively solving the problem of accurate three-dimensional positioning of spatial irregular structures.

[0022] 4. In this invention, the steel-concrete composite cable tower is hoisted as a whole and formed in one go, reducing the force system conversion during segmentation and minimizing material usage. Overall hoisting reduces tower offset, minimizes temporary site occupation time, makes construction safer, simpler to operate, ensures reasonable force distribution, saves steel, and provides better stress distribution. The double-layer positioning frame at the bottom facilitates construction and ensures precise tower positioning.

[0023] 5. In this invention, pumping micro-expansion concrete inside the tower ensures the continuity of concrete pouring. The chute inside the tower is set in advance, requiring fewer steel beams, which can effectively reduce the concrete sliding speed and ensure concrete quality. Construction is safer and operation is more convenient. No special equipment is required, the operation process is simple, and the construction cost is low.

[0024] 6. In this invention, the suspension cables are tensioned in segments, which allows for a reasonable deployment of the tensioning sequence and tension force, making construction safer, operation more convenient, more flexible, and with reasonable stress distribution. It also requires less equipment and reduces construction costs.

[0025] 7. This invention can be adapted to the construction of double-tower double-cable-stayed bridges with various irregular structures, complex stress systems, and frequent system transitions. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the lattice column in an embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram of the tower base positioning frame in an embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of the inclined chute in an embodiment of the present invention.

[0029] In the diagram: 1. Lattice column; 2. Arc-shaped support plate; 3. 12 sawtooth positioning rings; 4. Opening and closing positioning rings; 5. Trapezoidal stop; 6. Inclined chute; 7. Arc-shaped protrusion. Detailed Implementation

[0030] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations. Example

[0031] A rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge includes the following steps:

[0032] S1. Construction of Temporary Support System: Using Midas software, the spatial center of gravity of the main bridge structure and several support points are calculated after the suspension cables are tensioned. A floating platform is erected on the river surface. After acceptance, steel pipe piles are driven into the support points using a driving and pulling machine. The steel pipe piles are D529mm steel pipe piles, with a pile length of 22m, a penetration depth of 14m, and a pile spacing of 9m. After the steel pipe piles are driven into place, the excess steel pipe piles are cut off, and the top of the piles is required to be cut flat.

[0033] A 70*70*2cm head plate is installed at the center of the upper opening of the steel pipe pile. A double H-beam is installed above the head plate, and the contact surfaces of the head plate and the double H-beam are fully welded together to prevent deformation due to uneven stress during the installation of the steel box girder. Several 2cm thick stiffening plates are installed between the flanges of the double H-beam at the pile head location, spaced 250mm apart, and several more 2cm thick stiffening plates are installed between the flanges at other locations, spaced 500mm apart. The contact surfaces of the stiffening plates and the double H-beam are fully welded together.

[0034] A stable temporary support system is formed by welding figure-eight braces on both sides of the double H-beams. The figure-eight braces are made of round steel pipes with a diameter of 250mm and a wall thickness of 7mm.

[0035] A crossbeam is installed at the upper end of the double H-beams, and several main ribs are installed at the upper end of the crossbeam along the transverse direction. The main ribs are made of 30cm high 20#a I-beams (200*100*7mm). The lower end of the main ribs is fully welded to the top perimeter of the crossbeam by a 300*200*20mm steel plate.

[0036] S2. Bridge main body construction: Steel box girder segments are hoisted in sequence, and welding and process evaluation between steel box girder segments are carried out in a timely manner. After passing the evaluation, the whole bridge main body is hoisted and lowered onto the main rib. The upper end of the main rib is spot-welded to the bottom perimeter of the steel box girder through a 300*200*20mm steel plate.

[0037] S3. Construction of lattice columns: A double-layered 2m*5m*0.2m roadbed box is set at the upper end of the main bridge structure as a reference surface. Temporary support plates are welded around the roadbed box and fixed to the main bridge structure. Two sets of 2.5m*2.5m lattice columns 1 are installed at the upper end of the reference surface as temporary supports for the tower body. Figure 1As shown, the lattice column 1 uses four Ф426*12mm steel pipes as the main limbs and [16a as the horizontal and diagonal supports. When the steel pipes are extended, flanges and 12M20×85 bolts are used for connection. Each support is connected to the steel pipe with 8M20×55 bolts.

[0038] Before the placement of lattice column 1, the planar position and elevation of the support points are accurately measured and laid out onto lattice column 1. The orientation and elevation are then controlled using a tooling platform. After assembly, the overall dimensions and position of lattice column 1 are measured and inspected, ensuring that the splicing accuracy and overall dimensions meet design requirements. To ensure safety, during use, a guy rope is installed at two-thirds of the height of lattice column 1 in four directions. The guy ropes are bolted to the pre-welded lifting lugs on the steel box girder. An arc-shaped support plate 2 is installed at the top of lattice column 1. The arc-shaped support plate 2 is made of steel plate bent into a semi-circular arc shape, forming a tight connection with the tower body. A rubber pad is placed between the two to protect the tower wall. The arc-shaped support plate 2 is welded to lattice column 1, and the weld must meet the Class III weld standard.

[0039] S4. Tower Construction: The tower is constructed using steel-concrete composite pipes. The tower body is pre-assembled, and after welding inspection and approval, it is ground and rust-removed. The weld seams are then painted in preparation for hoisting. Before installation and fixing, the tower's horizontal position is determined, and the elevation is adjusted. Spatial positioning is achieved throughout the process using a total station. To prevent lateral displacement, a tower base positioning frame is welded onto the tower platform (with embedded steel plates) to precisely position the tower. During hoisting, the top of the tower is temporarily supported by lattice columns 1.

[0040] like Figure 2 As shown, the tower base positioning frame adopts a double-layer ring positioning frame. The lower positioning ring is a 12-tooth serrated positioning ring 3 with a diameter 1cm larger than the diameter of the tower base. The inner diameter of the 12-tooth serrated positioning ring 3 is 151cm, the outer diameter is 200cm, the serration width is 1cm, and the tooth depth is 26cm. The upper positioning ring is an opening and closing positioning ring 4. The opening and closing positioning ring 4 is perpendicular to the tower axis. The inner diameter of the opening and closing positioning ring 4 is 1cm larger than the diameter of the tower, and the outer diameter is 5cm larger than the inner diameter of the ring. Trapezoidal blocks 5 can be rotatably installed on both sides of the 12-tooth serrated positioning ring 3. The upper end of the trapezoidal block 5 is fixedly connected to the opening and closing positioning ring 4. The trapezoidal block 5 is 60cm high, 25cm long at the bottom, and 15cm long at the top. The form of the block can be determined using Revit software.

[0041] S5. Concrete Construction: In advance, collaborate with the commercial concrete plant to design the mix proportions and prepare suitable micro-expansion self-compacting concrete. During pumping, utilize the inclined chutes 6 pre-installed on the inner wall of the tower for pumping. For example... Figure 3As shown, the width of the inclined chute 6 is 60cm. Every 50cm in the inclined chute 6, a circular arc protrusion 7 with a radius of 10cm is set horizontally to reduce the flow velocity.

[0042] S6. Segmented tensioning of suspenders: After the concrete of the tower reaches the design strength, the suspenders are tensioned segment by segment.

[0043] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structures made using the contents of the present invention specification and drawings, whether directly or indirectly applied to other related technical fields, are similarly within the patent protection scope of the present invention.

Claims

1. A rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge, characterized in that, Includes the following steps: S1. Construction of temporary support system: Calculate the spatial center of gravity of the main body of the bridge and several support points after the suspension cables are tensioned. Construct an underwater operating platform on the river surface. Drive steel pipe piles at the support points. After the steel pipe piles are driven into place, install a head plate at the top of the steel pipe piles. Install double H-beams at the top of the head plate. Install a crossbeam at the top of the double H-beams. Install several main ribs along the transverse direction at the top of the crossbeams. Weld the lower ends of the main ribs to the top of the crossbeams with steel plates. S2. Bridge main body construction: Steel box girder segments are hoisted in sequence, welding and process evaluation are carried out between steel box girder segments, and after passing the evaluation, the whole bridge main body is hoisted and lowered onto the main rib. The upper end of the main rib is spot welded to the bottom perimeter of the steel box girder through steel plates. S3. Construction of lattice columns: Two sets of lattice columns are installed at the upper end of the main body of the bridge as temporary supports for the tower body. An arc-shaped support plate is set on the top of the lattice columns. The arc-shaped support plate is tightly integrated with the tower. A rubber pad is set between the two to protect the tower wall. S4. Tower Construction: The tower body is pre-assembled and, after passing welding inspection, is ready for hoisting. Before the tower body is installed and fixed, a tower base positioning frame is welded on the tower platform to adjust the left and right positions and accurately position the tower body. During hoisting, the top of the tower body is temporarily supported by the lattice column. The tower base positioning frame adopts a double-layer ring positioning frame. The lower positioning ring adopts a serrated positioning ring with a diameter larger than the diameter of the tower body bottom. The upper positioning ring adopts an opening and closing positioning ring. The opening and closing positioning ring is perpendicular to the tower body axis. The inner diameter of the opening and closing positioning ring is larger than the tower body diameter, and the outer diameter is larger than the inner diameter of the ring. Trapezoidal blocks are rotatably installed on both sides of the serrated positioning ring. The upper end of the trapezoidal blocks is fixedly connected to the opening and closing positioning ring. S5. Concrete construction of the tower: The mix design is carried out in advance to prepare a suitable micro-expansion self-compacting concrete, which is pumped in using the inclined chute pre-reserved on the tower body during the pumping process. S6. Segmented tensioning of suspenders: After the concrete of the tower reaches the design strength, the suspenders are tensioned segment by segment.

2. The rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge as described in claim 1, characterized in that, In S1, several 2cm thick stiffening plates are installed between the flange plates at the pile head position on the double H-beam, with a spacing of 250mm, and several 2cm thick stiffening plates are installed between the flange plates at other positions, with a spacing of 500mm.

3. The rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge as described in claim 1 or 2, characterized in that, In S1, figure-eight braces are set on both sides of the double H-beams to form a stable temporary support system. The figure-eight braces are made of round steel pipes with a diameter of 250mm and a wall thickness of 7mm.

4. The rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge as described in claim 1 or 2, characterized in that, In S3, during the use of the lattice column, a guy rope is installed in each of the four directions at two-thirds of its height, and the guy rope is bolted to the pre-welded lifting lugs on the steel box girder.

5. The rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge as described in claim 1 or 2, characterized in that, In S3, the arc-shaped support plate is made of steel plate bent into a semi-circular arc shape.

6. The rapid construction method for an irregularly shaped double-tower, double-cable-stayed bridge as described in claim 1 or 2, characterized in that, In S5, several arc-shaped protrusions are arranged laterally in the inclined chute to reduce the flow velocity.

Images