Suspension anchor ring system conversion and tensioning control method

Abstract

This invention provides a method for the conversion and tension control of a suspended anchor ring system, comprising: after the two upper tower columns are vertically rotated into place and the flexible anchor ring is raised into place, fixing the flexible anchor ring to the anchor tower; symmetrically tensioning the upper, lower, and middle tower ring cables between the flexible anchor ring and the two upper tower columns; symmetrically tensioning the tower beam cables near the outer side between the two upper tower columns and the main beam; separating the flexible anchor ring from the anchor tower, thus freeing the flexible anchor ring; symmetrically tensioning the other tower ring cables between the flexible anchor ring and the two upper tower columns; and symmetrically tensioning the other tower beam cables between the two upper tower columns and the main beam. This invention follows the principle of "prioritizing anchor ring balance and freeing constraints as early as possible." After symmetrically tensioning some tower ring cables and the outer tower beam cables to form a stable force-bearing system, the flexible anchor ring is promptly separated from the anchor tower, avoiding the problem of unclear force caused by temporary constraints from the anchor tower. This makes the structural force clear and controllable during subsequent system conversion, reducing construction risks.

Description

Technical Field

[0001] This invention relates to the field of construction technology for spatial flexible anchor ring double-arch cable-stayed bridges, specifically to a method for conversion and tension control of a suspended anchor ring system. Background Technology

[0002] In a spatially flexible anchor ring double-arch cable-stayed bridge, the flexible anchor rings are connected to the double-arch towers via a cable system, forming a self-balancing force system. During the construction of this type of bridge, ensuring a smooth and controllable transition of the structural system from the temporary construction state to the designed bridge state is crucial to guaranteeing that the bridge's alignment and internal forces meet design requirements. Currently, existing double-arch cable-stayed bridges do not incorporate flexible anchor rings, and there are no relevant construction case studies to guide the construction of the cable stays between the flexible anchor rings and the arch towers. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for the conversion and tension control of a suspended anchor ring system. Following the principle of "prioritizing anchor ring balance and removing constraints as early as possible," after symmetrically tensioning the tower ring cables and outer tower beam cables to form a stable force-bearing system, the flexible anchor ring is promptly separated from the tower. This avoids the problem of unclear force caused by the temporary constraints of the tower, making the structural force clear and controllable during subsequent system conversion and reducing construction risks.

[0004] To address the aforementioned technical problems, this invention provides a method for converting and controlling the tension of a suspended anchor ring system, comprising: After the two upper tower columns are vertically rotated into place and the flexible anchor rings are raised to the correct position, the flexible anchor rings are fixed to the tower, and the tower ring cables between the flexible anchor rings and the two upper tower columns are symmetrically tensioned on the upper, lower, and middle sides. Symmetrical tensioning of the tower-beam cables between the two upper tower columns and the main beam, near the outer side; Separate the flexible anchor ring from the buckle tower and remove the flexible anchor ring; Symmetrically tensioned flexible anchor rings and other tower ring cables between the two upper tower columns; Symmetrically tension the other tower and beam cables between the two upper tower columns and the main beam.

[0005] In some embodiments, before the flexible anchor ring is removed, the tension of the tensioned tower ring cable is monitored and adjusted so that the tension of the tensioned tower ring cable is stabilized within the design tension deviation range.

[0006] In some embodiments, after the flexible anchor ring is released, the tensioning of other tower ring cables and other tower beam cables is carried out in the following manner: Symmetrical, staged tensioning using a through-hole jack was employed, with real-time monitoring of the spatial coordinates of the flexible anchor ring and detection of the tension in each cable. The cable tension and flexible anchor ring coordinates in the finite element analysis model were compared with the actual cable tension and flexible anchor ring coordinates, and the cable tension was adjusted to ensure that the flexible anchor ring was within the design allowable deviation range. After the initial tensioning of other tower ring cables and other tower beam cables was completed, the cables were adjusted as a whole to ensure that the position of the flexible anchor ring, cable tension, and the position of the main tower met the design requirements.

[0007] In some embodiments, during the tensioning of the cable, the internal force of the cable and the internal force of the corresponding flexible anchor ring are monitored in real time to control the internal force of the cable and the internal force of the flexible anchor ring to be within the design range.

[0008] In some embodiments, the other tower ring cables between the symmetrically tensioned flexible anchor ring and the two upper tower columns include: The other tower ring cables are tensioned in order of distance from the central tower ring cable, with at least eight tower ring cables tensioned at a time. The two upper tower columns are designated as the first upper tower column and the second upper tower column. The eight tower ring cables include four tower ring cables between the first upper tower column and the flexible anchor ring, and four tower ring cables between the second upper tower column and the flexible anchor ring. The four tower ring cables between the first upper tower column and the flexible anchor ring are symmetrical to the four tower ring cables between the second upper tower column and the flexible anchor ring. The four tower ring cables between the first upper tower column and the flexible anchor ring include the two tower ring cables above the central tower ring cable and the two tower ring cables below the central tower ring cable. The two tower ring cables above the central tower ring cable are symmetrical, and the two tower ring cables below the central tower ring cable are symmetrical.

[0009] In some embodiments, the symmetrical tensioning of other tower-beam cables between the two upper tower columns and the main beam includes: The other tower and beam cables are tensioned in order from the outermost cable to the outermost cable, with at least four cables tensioned at a time. The two upper tower columns are designated as the first and second upper tower columns. The four cables include two cables between the first upper tower column and the main beam, and two cables between the second upper tower column and the main beam. The two cables between the first upper tower column and the main beam are symmetrical with the two cables between the second upper tower column and the main beam.

[0010] In some embodiments, after all the tower-beam cables have been tensioned, the traction cable between the upper tower column and the anchor tower is removed.

[0011] In some embodiments, the detached flexible anchor ring specifically includes: releasing the fixing of the tower and the limiting bracket, disassembling the limiting bracket, so that the flexible anchor ring is suspended and fixed only by the tensioned tower ring cable.

[0012] In some embodiments, during the process of detaching the flexible anchor ring, the spatial coordinates of the flexible anchor ring are monitored in real time using a BeiDou positioning fusion device, and the tension of the tensioned tower ring cable is adjusted in real time according to the spatial coordinates to control the position of the flexible anchor ring to meet the design range.

[0013] In some embodiments, when fixing the flexible anchor ring to the tower, a limiting bracket is used for fixing; the limiting bracket includes a frame and a plurality of limiting support plates disposed in the frame, the limiting support plates are provided with limiting grooves, the top and bottom of the flexible anchor ring are located in the limiting grooves, and a gap is provided between the flexible anchor ring and the limiting grooves, the gap is used to allow the two half rings of the flexible anchor ring to move relative to each other after the bolts between the connecting plate and the end block are subsequently loosened.

[0014] The beneficial effects of this invention are as follows: 1. This invention follows the principle of "prioritizing anchor ring balance and removing constraints as early as possible". After symmetrically tensioning the tower ring cables and the outer tower beam cables to form a stable force system, the flexible anchor ring is promptly separated from the tower. This avoids the problem of unclear force caused by the temporary constraint of the tower, making the structural force clear and controllable during the subsequent system conversion process, and reducing construction risks.

[0015] 2. This invention adopts a "step-by-step symmetrical tensioning" strategy, which clarifies the tensioning sequence of the tower ring cables from the middle to both sides and the tower beam cables from the outside to the inside. Combined with cable force monitoring, real-time observation of the spatial coordinates of the flexible anchor rings (such as Beidou positioning), and comparison and adjustment of the finite element model, it realizes closed-loop control of cable force and anchor ring position, ensuring that the final alignment and internal forces of the flexible anchor rings and main towers meet the design allowable deviation range, thus improving the quality of the completed bridge.

[0016] 3. This invention, through two stages of control measures—"monitoring stability before cable separation" and "staged tensioning + overall cable adjustment after cable separation"—ensures the safety of the cable separation operation and provides a clear adjustment path for the subsequent tensioning of a large number of cables. This method effectively solves the technical challenges of conversion and tension control in spatial flexible anchor ring double-arch cable-stayed bridge systems and has significant potential for widespread application. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a spatial flexible anchor ring double-arch cable-stayed bridge in an embodiment of the present invention; Figure 2 This is a front view of the arch tower of the present invention; Figure 3 This is a top view of the main tower of the present invention; Figure 4 This is a schematic diagram of the structure of the flexible anchor ring after installation of the present invention; Figure 5 This is a schematic diagram of the structure when the two semi-rings of the present invention are connected; Figure 6 This is a schematic diagram of the installation of the circumferential cable of the present invention; Figure 7 This is a schematic diagram of the closure of the circumferential cable of the present invention; Figure 8 This is a schematic diagram of the closure section of the circumferential cable of the present invention; Figure 9 This is a schematic diagram illustrating the verification and adjustment of the cable force of the circumferential cable according to the present invention; Figure 10 This is a schematic diagram of the structure of the cable tower of the present invention; Figure 11 This is a schematic diagram showing the connection between the cable tower and the main beam of the present invention; Figure 12 This is a construction schematic diagram of the YM1 segment of the present invention; Figure 13 This is a schematic diagram of the connection structure of the tower base, lower tower column, and main beam of the present invention; Figure 14 This is a schematic diagram of the arrangement of the prestressed ducts of the present invention; Figure 15 This is a top view schematic diagram of the construction of segments CT1 to CT4 of the present invention; Figure 16 This is a construction elevation view of the CT1~CT4 segments of the present invention; Figure 17 This is a schematic diagram of the arrangement of the horizontal assembly support frame of the present invention; Figure 18 This is a construction schematic diagram of the main tower column on the west side of the main tower of this invention; Figure 19 This is a construction schematic diagram of the TS2~TS6 segments of the main tower column on the east side of the main tower of the present invention; Figure 20 This is a construction schematic diagram of the TS7, TY1, and TY2 segments of the main tower column on the east side of the main tower of this invention; Figure 21 This is a construction diagram of the TY3 and TY4 segments of the main tower column on the east side of the main tower and the TS0 and TS1 segments of the main tower column on the west side of the main tower of the present invention. Figure 22 This is a schematic diagram showing the connection between the upper hinge seat and the lower hinge seat of the present invention; Figure 23 This is a schematic diagram of the connection of the traction cable of the present invention; Figure 24 This is a schematic diagram of the vertical rotation of the upper tower column into place according to the present invention; Figure 25 This is a construction schematic diagram of the TZ6 tower ring cable of the present invention; Figure 26 This is a construction schematic diagram of the TZ1 and TZ11 tower ring cables of the present invention; Figure 27This is a construction schematic diagram of the TL8~TL10 and BL8~BL10 tower-beam cables of the present invention; Figure 28 This is a construction schematic diagram of the remaining tower ring cables of the present invention; Figure 29 This is a construction schematic diagram of the remaining tower-beam cables of the present invention; Figure 30 This is a schematic diagram of the jacking construction of the main beam of the present invention.

[0018] Reference numerals: Main beam 1; Main tower 2; Tower base 21; Lower tower column 22; Lower tower column foundation 221; Lower tower column segment 222; Upper tower column 23; Lower hinge seat 24; Upper hinge seat 25; Pin shaft 26; Permanent pier 3; Flexible anchor ring 4; Half ring 41; End block 42; Upper connecting plate 43; Lower connecting plate 44; Circumferential cable 45; Sleeve 451; Pad beam 452; External stiffening rib 46; Reaction frame 47; Tower ring cable 5; Tower beam cable 6; Crossbeam 7; Tower buckle 8; In-situ horizontal splicing support 9; Sliding support 10; Prestressed duct 11. Detailed Implementation

[0019] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] This invention is illustrated using a spatial flexible anchor ring double-arch cable-stayed bridge as an example.

[0021] like Figure 1 As shown, the total length of the spatial flexible anchor ring double arch cable-stayed bridge is 768m, including the main bridge in the middle and the west approach bridge and east approach bridge at both ends of the main bridge. The bridge span arrangement is 2×78+(88+2×160+58)+2×68m. There are 9 permanent piers 3, namely A0, P1, P2, P3, P4, P5, P6, P7 and A8. The main pier is located at pier P4, and the main tower 2 is built on it.

[0022] like Figure 2 , 3 As shown, the main tower 2 includes two arch towers connected at the bottom. The arch towers present the effect of a Möbius strip. The arch towers include an upper tower column 23 and a lower tower column 22. The upper tower column 23 is a steel box structure, and the lower tower column 22 is a steel-concrete composite structure.

[0023] The lower tower column 22 includes four parts: YM1, CT1, CT2, CT3, and CT4. The YM1 segment is the part where the two arch towers are connected as one unit. It is fixedly connected to the tower base 21. The YM1 segment is provided with four legs. The CT1, CT2, CT3, and CT4 segments are respectively fixed on the four legs of the YM1 segment.

[0024] The upper tower column 23 includes segments TS0, TS1, TS2, TS3, TS4, TS5, TS6, TS7, TX1, TX2, TX3, and TX4. One segment TS0 is provided, located at the top of the upper tower column 23, while two segments are provided for each of the other segments.

[0025] like Figure 22 As shown, an upper hinge seat 25 and a lower hinge seat 24 are respectively provided in the upper tower column 23 and the lower tower column 22, and the upper hinge seat 25 and the lower hinge seat 24 are rotatably connected by a pin 26. Figure 22 In the middle, the left side is the main view of the connection between the upper hinge seat 25 and the lower hinge seat 24 (the line of sight is along the transverse bridge direction), and the right side is the side view of the connection between the upper hinge seat 25 and the lower hinge seat 24.

[0026] like Figure 4 As shown, the main beam 1 and the lower tower column 22 are welded together by a crossbeam 7, which includes a bottom crossbeam 7 plate, a side crossbeam 7 plate, and a top crossbeam 7 plate.

[0027] like Figure 1 As shown, a flexible anchor ring 4 is installed between the two arch towers. The flexible anchor ring 4 is connected to the upper tower column 23 of the arch tower by a tower ring cable 5. The main beam 1 is connected to the upper tower column 23 of the arch tower by a tower beam cable 6. The tower beam cable 6 is distributed between piers P3 and P4.

[0028] like Figure 5 As shown, the flexible anchor ring 4 includes two semi-rings 41, which are symmetrically arranged with their ends facing each other. Each end of the two semi-rings 41 is fixedly welded to an end block 42. Multiple rows of circular screw holes are formed on the end block 42, with a spacing of 'a' between adjacent rows. The arrangement direction of the circular screw holes in each row is parallel to the end face of the end block 42. Adjacent end blocks 42 are fixedly connected by a connecting plate, which has oblong holes corresponding to the circular screw holes. The connecting plate includes an upper connecting plate 43 and a lower connecting plate 44. The upper connecting plate 43 connects the two end blocks 42 at the top of the flexible anchor ring 4, and the lower connecting plate 44 connects the two end blocks 42 at the bottom of the flexible anchor ring 4.

[0029] Multiple circumferential grooves are opened on the outer side of each of the two semi-rings 41, and circumferential cables 45 are installed in the circumferential grooves. When the flexible anchor ring 4 is finished in the factory, the circumferential cables 45 are in a relaxed state, and when it is connected to the main tower 2, the circumferential cables 45 are gradually tightened.

[0030] The semi-ring 41 includes a steel box, which includes a top plate and a bottom plate. Both the top plate and the bottom plate are annular. A web plate is provided between the top plate and the bottom plate. The web plate is perpendicular to the top plate and the bottom plate and is welded to them. End sealing plates are provided at both ends of the top plate and the bottom plate. The end sealing plates are welded to the top plate, the bottom plate and the web plate.

[0031] Multiple internal stiffening ribs and multiple external stiffening ribs 46 are respectively provided on the inner and outer sides of the web. The multiple internal stiffening ribs and multiple external stiffening ribs 46 are arranged correspondingly. Anchor ring saddles are installed on the external stiffening ribs 46, and the anchor ring saddles are used to install the stay cables. Weight reduction holes and manholes are provided on the steel box.

[0032] The construction methods for this spatial flexible anchor ring double-arch cable-stayed bridge include: S1, permanent pier 3 and temporary pier.

[0033] Construction will involve nine permanent piers (A0, P1, P2, P3, P4, P5, P6, P7, and A8), with temporary piers to be constructed between them. Because there is a mangrove forest to the east of the main tower 2, construction will need to cross this mangrove forest. Additionally, a navigation area needs to be reserved to the west of the main tower 2. Therefore, the location of the temporary piers should avoid the mangrove forest and the navigation area.

[0034] S2. The main beam 1 is constructed using the jacking method, while the tower base 21, lower tower column 22, tower clamp 8, horizontal splicing support, and upper tower column 23 are constructed simultaneously.

[0035] Construction of main beam 1: as follows Figure 30 As shown, steel box girder assembly platforms were set up on piers P2 and P3. The main girder 1 of the main bridge and the west approach bridge was constructed by in-situ segmented installation using floating cranes and bidirectional jacking. The east approach bridge was installed by jacking towards the main bridge using land assembly and jacking methods.

[0036] Construction horizontal scaffolding: such as Figure 17 As shown, while the main beam 1 was being jacked up, horizontal splicing scaffolds were being constructed on both sides of the bridge. Because the mangrove forest area to the east of the main tower 2 was quite large, if the in-situ horizontal splicing method were used, it would require constructing the horizontal splicing scaffolds and corresponding piles within the mangrove forest area, which would cause extensive damage to the mangrove forest by the working vessels and other equipment. Therefore, the upper tower column 23 on the west side of the main tower 2 was constructed entirely using the in-situ horizontal splicing method, while the upper tower column 23 on the east side of the main tower 2 was constructed using a combination of sliding horizontal splicing and partial in-situ horizontal splicing.

[0037] On the west side of the main tower 2, multiple in-situ horizontal splicing supports 9 are constructed according to the shape and outline of the upper tower column 23 when it is lying flat. The multiple in-situ horizontal splicing supports 9 are symmetrically arranged on both sides of the main beam 1. On the east side of the main tower 2 and between the mangrove forest, multiple sliding supports 10 are constructed according to the support range required for the sliding of the upper tower column 23 after it is lying flat. Both the in-situ horizontal splicing supports 9 and the sliding supports 10 are constructed using a floating crane.

[0038] Construction of tower base 21 and lower tower column 22: Tower base 21 is constructed in layers. Tower base 21 includes upper tower base 21 and lower tower base 21. Lower tower column 22 includes a lower tower column foundation 221YM1 and multiple lower tower column segments 222CT1~CT4.

[0039] The construction tower base 21 and lower tower column 22 include: Tie the reinforcing bars of the lower tower base 21, construct the steel shell of the lower tower base 21, and pour the concrete of the lower tower base 21. Tie the reinforcing bars of the upper tower base 21, and pre-embed the reinforcing bars of the lower tower column foundation 221, such as... Figure 12 As shown, the construction involves the steel shell of the upper tower base 21 and the steel shell of the lower tower column foundation 221, followed by the pouring of concrete for the upper tower base 21 and the pouring of concrete for the lower tower column foundation 221. Figure 13 As shown.

[0040] After the concrete pouring of the lower tower column foundation 221 is completed, the construction of the lower tower column segment 222 will proceed, such as... Figure 15 , 16 As shown; The steel shell and reinforcing bars of the lower tower column segment 222 are prefabricated as a whole in the factory. The lower hinge seat 24 is welded to the lower tower column segment 222 as a whole in the factory and then transported to the construction site for installation. During installation, the pin 26 is inserted into the pin 26 hole of the lower hinge seat 24. Multiple measurement control points are arranged on the pin 26 of the lower hinge seat 24. The lower tower column segment 222 is connected to the steel shell and reinforcing bar lower tower column foundation 221. The orientation of the pin 26 is measured through the measurement control points, and the lower tower column segment 222 is adjusted so that the pin 26 is aligned. With shaft 26 in a horizontal position and perpendicular to the bridge centerline, the lower tower column segment 222 is welded to the lower tower column foundation 221. The coordinates of the control points of the pin shaft 26 are re-measured. After the requirement that the pin shaft 26 is in a horizontal position and perpendicular to the bridge centerline is met, the other lower tower column segments 222 are installed using the same method. After all the lower tower column segments 222 are installed, the coaxiality of the symmetrical lower hinge seats 24 is measured. After the coaxiality requirement is met, the concrete of the lower tower column segments 222 is poured.

[0041] Construction of Tower 8: Construction of Tower 8 can begin after the lower tower column 22 is completed. For example... Figure 10 As shown, Figure 10 The left side of the image shows the front view of Tower 8, and the right side shows its left view. Tower 8 is a 5.5m × 6m lattice tower, 97.971m high, consisting of two units. The uprights are made of 1000mm diameter steel pipes, while the horizontal and diagonal braces are made of 630mm diameter steel pipes. Three horizontal connection systems are installed between Tower 8 units, all using 630mm diameter steel pipes. Figure 11 As shown, in order to ensure the stability of the assembly and rotation process of the tower 8, a total of 3 layers (24) of cable anchor points are set on the tower 8, with the anchor points being 30.971m, 70.971m and 95.971m from the bottom of the tower respectively.

[0042] Tower 8 is manufactured as a single piece in the factory. After being transported to the site, it is pre-assembled into units and hoisted using a tower crane. Standard sections are connected with high-strength bolts. During the installation of Tower 8, a 600t.m tower crane is installed on both the upstream and downstream sides of the lower tower column 22 as lifting equipment. Each tower crane has two anchors on Tower 8, and the free cantilever height does not exceed 54m. The installation steps of Tower 8 are as follows: After the CT1 to CT4 segments were completed, a 610t floating crane was used to install the lower part of the tower 8 (83m high) on the steel tower segments. The bottom of the tower 8 was welded to the lower tower column 22, the first wind cable was hung, and the verticality of the tower 8 was adjusted. Two tower cranes were installed and the tower crane support walls were installed. The tower cranes were used to continue the installation of the remaining part of the tower 8 (14m high), the second wind cable was hung, the verticality of the tower 8 was adjusted, and the installation of the tower 8 was completed. The top horizontal connection was lifted by two tower cranes.

[0043] Construction of the upper tower column 23: In response to the problem that large-scale water hoisting operations cannot be carried out in the mangrove environmental protection area on the east side of the main tower, this invention proposes an asymmetrical horizontal splicing construction scheme.

[0044] The upper tower column 23 includes a first upper tower column 23 located on one side (west side) of the tower base 21 and a second upper tower column 23 located on the other side (east side) of the tower base 21. The first upper tower column 23 and the second upper tower column 23 are constructed using a combination of fully in-situ horizontal assembly, sliding horizontal assembly, and partially in-situ horizontal assembly methods, respectively. like Figure 30 As shown, the direction of the main girder 1 of the main bridge is from the first upper tower column 23 to the second upper tower column 23, that is, from west to east; like Figure 18 As shown, the TX1~TX4 and TS2~TS7 segments of the first upper tower column 23 are assembled on the in-situ horizontal assembly support 9. After the main beam 1 is pushed into place, that is, the main beam 1 is pushed to the design position, the TS0 and TS1 segments of the first upper tower column 23 are assembled on the main beam 1 to complete the assembly of the first upper tower column 23. When assembling the TX1~TX4 and TS2~TS7 segments of the first upper tower column 23 on the in-situ horizontal assembly support 9, the segments at a distance from the lower tower column 2 are assembled first. 2. Connect one or more segments of the first upper tower column 23 (TX4 segment, or TX3, TX4 segment, or TX2, TX3, TX4 segment, or TX1, TX2, TX3, TX4 segment) to the upper hinge seat 25 of the first upper tower column 23 (the upper hinge seat 25 of the first upper tower column 23 is fixedly connected to the TX4 segment) and the lower hinge seat 24 of the lower tower column 22 through the pin 26. Finally, assemble the other segments of the first upper tower column 23.

[0045] There are two construction methods for the second upper tower column 23. One method is to construct the second upper tower column 23 after the main beam 1 has been pushed to the design position. The other method is to construct the second upper tower column 23 during the process of pushing the main beam 1.

[0046] After the main beam 1 is pushed to the designed position, the construction of the second upper tower column 23 will proceed: After the main beam 1 is pushed to the designed position, a slide rail is installed on the main beam 1, and a sliding frame is installed on the slide rail. The top segments (TS0 and TS1 segments) of the second upper tower column 23 are hoisted onto the sliding frame and spliced. The TS2 to TS6 segments of the second upper tower column 23 are hoisted onto the sliding supports 10 on both sides of the main beam 1 and spliced. After the spliced ​​segments (TS0 to TS6 segments) are slid to the east by one distance, the TS7, TY1, and TY2 segments of the second upper tower column 23 are spliced. After the spliced ​​segments are slid to the east by one distance again, the TY3 and TY4 segments of the second upper tower column 23 are spliced. At this point, the splicing of the second upper tower column 23 is completed.

[0047] During the jacking of main beam 1, the second upper tower column 23 is constructed: (e.g.) Figure 18 As shown, after the main beam 1 is pushed a certain distance beyond the east side of the tower base 21, the top segments (TS0 and TS1 segments) of the second upper tower column 23 are assembled on the main beam 1, as follows: Figure 19 As shown, the TS2~TS6 segments of the second upper tower column 23 are hoisted onto the sliding supports 10 on both sides of the main beam 1 and spliced. The assembled segments of the second upper tower column 23 (TS0~TS6 segments) are pushed forward along with the main beam 1 under the action of the sliding supports 10. Every time the main beam 1 is pushed a certain distance, a partial assembly of the second upper tower column 23 is performed on the sliding supports 10, such as... Figure 20 , 21 As shown, this continues until the second upper tower column 23 is assembled. This method can shorten the construction period.

[0048] It should be noted that during the construction of the second upper tower column 23, when assembling the last section (TY3 and TY4 sections) of the second upper tower column 23, the last section of the second upper tower column 23 is first assembled with each other, that is, the TY3 and TY4 sections are assembled. Then, the upper hinge seat 25 of the second upper tower column 23 (the upper hinge seat 25 of the second upper tower column 23 is fixedly connected to the TY4 section) and the lower hinge seat 24 of the lower tower column 22 are connected by the pin 26. Finally, the last section of the second upper tower column 23 is connected with the other sections of the second upper tower column 23, that is, the TY3 section is welded to the TY2 section.

[0049] S3. After the main beam 1 is pushed into place, connect the lower tower column 22 to the main beam 1.

[0050] The truck crane is located on the main beam 1. The truck crane is used to install welding platforms at various locations, and the bottom crossbeam 7 plates, side crossbeam 7 plates, and top crossbeam 7 plates are hoisted and welded in sequence. like Figure 14As shown, prestressed ducts 11 are pre-embedded in the main beam 1 and the lower tower column 22. The corresponding prestressed ducts 11 are extended by using sleeves to connect the prestressed ducts 11 of the main beam 1 and the lower tower column 22. Steel strands are installed in the prestressed ducts 11 and prestressing is performed. The prestressed ducts 11 are grouted within 24 hours after the prestressing is completed.

[0051] S4, such as Figure 23 and 24 As shown, the upper tower column 23 is connected to the tower 8 by a traction cable. The upper tower column 23 is rotated vertically using the traction cable until it reaches the designed angle. The upper tower column 23 and the lower tower column 22 are then welded and fixed.

[0052] Before vertically rotating the upper tower column 23 using the traction cable, all wind cables of each layer of the tower 8 are connected to the top of the tower 8. When vertically rotating the upper tower column 23 using the traction cable, a lifting cylinder is used as the power source for the vertical rotation of the upper tower column 23. Each connection point between the traction cable and the upper tower column 23 is a lifting point. The height of each lifting point is detected by a distance sensor, and one of the lifting points is set as the master lifting point. The lifting cylinders of the other lifting points are adjusted with reference to the height position of the master lifting point to ensure that the positions of all lifting points are synchronized.

[0053] Before the formal vertical rotation, a trial rotation is conducted: graded loading is applied until the upper tower column 23 is completely off the ground and hovers in the air for a certain period of time. During this period, the position and load of the lifting points are recorded, the actual load of each lifting point is compared with the theoretical calculated load, and the load parameters of each lifting point are adjusted according to the actual load; the stress and deformation of each structure are checked to see if they meet the design requirements.

[0054] After the vertical rotation is completed, the upper tower column 23 and the lower tower column 22 at the hinge are welded together. The welding of the upper tower column 23 and the lower tower column 22 uses steel plates, which are installed one by one using a 25t truck crane, proceeding clockwise from one side. During the steel plate installation process, the truck crane first lifts the steel plate to the installation position, then a hand-operated hoist lifts the steel plate to the designated position. After the construction personnel have installed the steel plate, the upper and lower sections are welded and fixed. Once securely fixed, the truck crane releases its hook to prepare for lifting the next steel plate.

[0055] S5. Raise the flexible anchor ring 4 to the designed height and fix it on the buckle tower 8.

[0056] Fabrication of the flexible anchor ring 4: Process two semi-rings 41 of the flexible anchor ring 4, place the two semi-rings 41 opposite each other so that the two semi-rings 41 can form a ring structure. Multiple rows of circular screw holes are opened on the side of the end block 42, with a spacing of a between two adjacent rows of circular screw holes. In each row of circular screw holes, the arrangement direction of the circular screw holes is parallel to the end face of the end block 42. The upper connecting plate 43 and the lower connecting plate 44 are opened with waist-shaped holes corresponding to the circular screw holes. Adjust the gap between two adjacent end blocks 42 to the designed gap -a. Use the upper connecting plate 43 and the lower connecting plate 44 to fix two pairs of adjacent end blocks 42 together with bolts to form a complete ring structure. Multiple circumferential cables 45 are fabricated according to their stress-free length. These cables are then installed one by one from the center of the annular structure outwards. The annular structure is secured using temporary fixing devices (such as brackets). The circumferential cables 45 are placed in the circumferential grooves outside the semi-rings 41. Two winches are used to pull the anchor heads at both ends of the circumferential cables 45 to the closing position, which is near the lower connecting plate 44. Pad beams 452 are installed on the two anchor heads, and precision-rolled threaded steel bars are installed on the pad beams 452. One end of the precision-rolled threaded steel bars is tightened using a through-hole jack to align the two anchor heads. After alignment, the circumferential cables 45 are closed using a sleeve 451. The sleeve 451 is screwed to the designed position, leaving the circumferential cables 45 in a relaxed state, with all cables of equal length. Since the gap between two adjacent end blocks 42 is the designed gap -a, the two semi-rings 41 do not tighten the circumferential cables 45, leaving them in a relaxed state.

[0057] After installing multiple circumferential cables 45 to form a flexible anchor ring 4 outside the ring structure, the circumferential cables 45 are verified and adjusted: Loosen the bolts on the upper connecting plate 43 and the lower connecting plate 44. Install the reaction frame 47 and the jack between the end faces of the two semi-rings 41. Connect the two ends of the jack to the reaction frame 47. The jack lifts according to the preset jacking force, causing the two semi-rings 41 to tend to move away from each other. At this time, the circumferential cable 45 is tensioned. Detect the cable force of multiple circumferential cables 45. If the deviation between the cable force of multiple circumferential cables 45 and the preset cable force is greater than the preset deviation, rotate the sleeve 451 to adjust part of the cable force of the circumferential cables 45 so that the deviation between the cable force of multiple circumferential cables 45 and the preset cable force meets the preset deviation. Disassemble the reaction frame 47 and the jack, adjust the gap between the two adjacent end blocks 42 to the design gap -a, and lock the bolts on the upper connecting plate 43 and the lower connecting plate 44. The preset jacking force corresponds to the preset cable force, that is, different preset jacking forces correspond to different preset cable forces. Different preset jacking forces can be used for multiple verifications to ensure that the stress of multiple circumferential cables 45 meets the design requirements. This step can reduce situations where multiple circumferential cables 45 are subjected to different forces, or the forces are large or small, due to processing errors or other reasons.

[0058] Lifting and fixing of the flexible anchor ring 4: Place the flexible anchor ring 4 on the limiting bracket, install the upper outer shell on the flexible anchor ring 4, install a lifting jack on the top of the tower 8, and use the lifting jack to lift the limiting bracket until the height of the flexible anchor ring 4 meets the installation space of the lower outer shell. Then install the lower outer shell on the flexible anchor ring 4. After the outer shell of the flexible anchor ring 4 is installed, lift the flexible anchor ring 4 to the designed position. Weld and fix the limiting bracket to the tower 8.

[0059] The limiting bracket includes a frame and four limiting support plates installed inside the frame. The four limiting support plates circumferentially surround and limit the flexible anchor ring 4 to restrict its movement. Limiting grooves corresponding to the flexible anchor ring 4 are opened on the limiting support plates. The top and bottom of the flexible anchor ring 4 are located in the limiting grooves, and a gap is set between the top of the flexible anchor ring 4 and the limiting grooves, so that in subsequent steps, after the bolts between the connecting plate and the end block 42 are loosened, the two half rings 41 can move relative to each other and apply stress to the circumferential cable 45.

[0060] S6. Use the stay cables to perform system conversion and tension control of the main tower 2 and flexible anchor ring 4.

[0061] The system conversion and tension control of this invention follow the principles of "prioritizing anchor ring balance, removing constraints as early as possible, and step-by-step symmetrical tensioning".

[0062] Step S6 includes: Symmetrically tensioned flexible anchor ring 4 and the upper, lower, and middle tower ring cables 5 between the two upper tower columns 23: as follows Figure 25 As shown, first tension the TZ6 tower ring cable 5 in the middle between the flexible anchor ring 4 and the two upper tower columns 23. Figure 25 The red line segment represents the TZ6 tower ring cable. Loosen the bolts between the upper connecting plate 43 and the end block 42, as follows: Figure 26 As shown, the upper TZ11 tower ring cable 51 between the flexible anchor ring 4 and the two upper tower columns 23 is tensioned again. When the gap between the end blocks 42 at the upper ends of the two half rings 41 reaches the design gap, the bolts between the upper connecting plate 43 and the end blocks 42 are locked. Then, the lower TZ1 tower ring cable 5 between the flexible anchor ring 4 and the two upper tower columns 23 is tensioned, and the bolts between the lower connecting plate 44 and the end blocks 42 are released. Figure 26 The red line segment on the upper middle side represents the TZ11 tower ring cable, and the red line segment on the lower side represents the TZ1 tower ring cable.

[0063] Among them, the TZ6 tower ring cable 5 can be tensioned before the flexible anchor ring 4 is detached, depending on the specific design scheme. That is, the TZ6 tower ring cable 5 can be installed and tensioned after the flexible anchor ring 4 is detached.

[0064] like Figure 27As shown, then symmetrically tension the TL8~TL10 tower beam cables 6 and BL8~BL10 tower beam cables 6 near the outer side between the two upper tower columns 23 and the main beam 1. Figure 27 The blue line segment on the left represents the TL8~TL10 tower beam cables, and the blue line segment on the right represents the BL8~BL10 tower beam cables. The tensioning sequence is from the inside out. Simultaneously, the cable tension of multiple TZ1 tower ring cables 5 and TZ11 tower ring cables 5 is monitored to ensure that the cable tension of multiple TZ1 tower ring cables 5 is stable within the design cable tension deviation range, the cable tension of multiple TZ11 tower ring cables 5 is equal and stable within the design cable tension deviation range, and the cable tension of multiple TZ6 tower ring cables 5 is equal and stable within the design cable tension deviation range. At this time, one side of the upper tower column 23 is connected to the main beam 1, and the other side is connected to the buckle tower 8 and the anchor ring, forming a stable structure. Therefore, the anchor ring can be detached, the buckle tower 8 can be released from the limit bracket, and the limit bracket can be disassembled, so that the flexible anchor ring 4 is only fixed by the tower ring cable 5. During the detachment process, the Beidou positioning fusion device of the flexible anchor ring 4 is used to monitor the spatial coordinates of the flexible anchor ring 4 in real time, and the cable force of TZ1 tower ring cable 5 and TZ11 tower ring cable 5 is adjusted in real time to control the position of the flexible anchor ring 4 to meet the design range.

[0065] By tensioning the stay cables of the tower beam, the anchor rings are released as early as possible, avoiding the problem of unclear force caused by the tower support as a temporary constraint, and making the structural force system clear and controllable.

[0066] like Figure 28 , 29 As shown, the other tower ring cables 5 between the flexible anchor ring 4 and the two upper tower columns 23 are tensioned symmetrically: first, the tower ring cables 5 of TZ5 and TZ7, TZ4 and TZ8, TZ3 and TZ9, and TZ2 and TZ10 are tensioned in sequence; then, the tower beam cables 6 of TL7 and BL7 are tensioned in sequence. After tensioning is completed, the traction cable between the tower and the fastening tower 8 can be removed.

[0067] S7. Construct the bridge deck system and other structures. After the bridge deck system is completed, lock the bolts between the lower connecting plate 44 and the end block 42.

[0068] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for conversion and tension control of a suspended anchor ring system, characterized in that: include: After the two upper tower columns (23) are vertically rotated into place and the flexible anchor ring (4) is lifted into place, the flexible anchor ring (4) is fixed on the buckle tower (8), and the tower ring cable (5) between the flexible anchor ring (4) and the two upper tower columns (23) is symmetrically tensioned on the upper side, lower side and middle of the tower ring cable (5). Symmetrically tension the tower-beam cables (6) between the two upper tower columns (23) and the main beam (1) near the outer side. Separate the flexible anchor ring (4) from the buckle tower (8) and remove the flexible anchor ring (4). Other tower ring cables (5) between the symmetrically tensioned flexible anchor ring (4) and the two upper tower columns (23); Symmetrically tension the other tower beam cables (6) between the two upper tower columns (23) and the main beam (1).

2. The method for conversion and tension control of the suspended anchor ring system according to claim 1, characterized in that: Before removing the flexible anchor ring (4), monitor and adjust the tension of the tensioned tower ring cable (5) so that the tension of the tensioned tower ring cable (5) is stable within the design tension deviation range.

3. The method for conversion and tension control of the suspended anchor ring system according to claim 1, characterized in that: After the flexible anchor ring (4) is removed, the tensioning of other tower ring cables (5) and other tower beam cables (6) is carried out in the following manner: Symmetrical and graded tensioning was carried out using a through-hole jack, and the spatial position coordinates of the flexible anchor ring (4) and the cable force of each cable were observed in real time. The cable force and coordinates of the flexible anchor ring (4) in the finite element analysis model were compared with the actual cable force and coordinates of the flexible anchor ring (4), and the cable force was adjusted so that the flexible anchor ring (4) was within the design allowable deviation range. After the other tower ring cables (5) and other tower beam cables (6) were initially tensioned as a whole, the cables were adjusted as a whole so that the position of the flexible anchor ring (4), the cable force, and the position of the main tower (2) met the design requirements.

4. The method for conversion and tension control of the suspended anchor ring system according to claim 1, characterized in that: During the tensioning of the cable, the internal force of the cable and the internal force of the corresponding flexible anchor ring (4) are monitored in real time to control the internal force of the cable and the internal force of the flexible anchor ring (4) to be within the design range.

5. The method for conversion and tension control of the suspended anchor ring system according to claim 1, characterized in that: The other tower ring cables (5) between the symmetrically tensioned flexible anchor ring (4) and the two upper tower columns (23) include: The other tower ring cables (5) are tensioned in order of proximity from the central tower ring cable (5), with at least eight tower ring cables (5) tensioned at a time. The two upper tower columns (23) are the first upper tower column and the second upper tower column, respectively. The eight tower ring cables (5) include four tower ring cables (5) between the first upper tower column and the flexible anchor ring (4) and four tower ring cables (5) between the second upper tower column and the flexible anchor ring (4). The four tower ring cables (5) between the first upper tower column and the flexible anchor ring (4) are tensioned. The four tower ring cables (5) between the first upper tower column and the flexible anchor ring (4) are symmetrical. The four tower ring cables (5) between the first upper tower column and the flexible anchor ring (4) include the two tower ring cables (5) on the upper side of the middle tower ring cable (5) and the two tower ring cables (5) on the lower side of the middle tower ring cable (5). The two tower ring cables (5) on the upper side of the middle tower ring cable (5) are symmetrical, and the two tower ring cables (5) on the lower side of the middle tower ring cable (5) are symmetrical.

6. The method for conversion and tension control of the suspended anchor ring system according to claim 5, characterized in that: The other tower-beam cables (6) symmetrically tensioned between the two upper tower columns (23) and the main beam (1) include: The other tower beam cables (6) are tensioned in order from the outermost tower beam cable (6) to the farthest. At least four tower beam cables (6) are tensioned each time. The two upper tower columns (23) are the first upper tower column and the second upper tower column, respectively. The four tower beam cables (6) include the two tower beam cables (6) between the first upper tower column and the main beam (1) and the two tower beam cables (6) between the second upper tower column and the main beam (1). The two tower beam cables (6) between the first upper tower column and the main beam (1) are symmetrical with the two tower beam cables (6) between the second upper tower column and the main beam (1). The two tower beam cables (6) between the first upper tower column and the main beam (1) are symmetrical with the two tower beam cables (6) between the second upper tower column and the main beam (1).

7. The method for conversion and tension control of the suspended anchor ring system according to any one of claims 1 to 6, characterized in that: After tensioning all the tower beam cables (6), remove the traction cable between the upper tower column (23) and the fastening tower (8).

8. The method for conversion and tension control of the suspended anchor ring system according to any one of claims 1 to 6, characterized in that: The detached flexible anchor ring (4) specifically includes: releasing the fixing of the buckle tower (8) and the limiting bracket, disassembling the limiting bracket, so that the flexible anchor ring (4) is suspended and fixed only by the tensioned tower ring cable (5).

9. The method for conversion and tension control of the suspended anchor ring system according to any one of claims 1 to 6, characterized in that: During the process of detaching the flexible anchor ring (4), the spatial coordinates of the flexible anchor ring (4) are monitored in real time using the Beidou positioning fusion device, and the tension of the tensioned tower ring cable (5) is adjusted in real time according to the spatial coordinates to control the position of the flexible anchor ring (4) to meet the design range.

10. The method for conversion and tension control of the suspended anchor ring system according to any one of claims 1 to 6, characterized in that: When the flexible anchor ring (4) is fixed on the buckle tower (8), a limiting bracket is used for fixing; the limiting bracket includes a frame and multiple limiting support plates set in the frame. A limiting groove is opened on the limiting support plate. The top and bottom of the flexible anchor ring (4) are located in the limiting groove, and a gap is provided between the flexible anchor ring (4) and the limiting groove. This gap is used to allow the two half rings (41) of the flexible anchor ring (4) to move relative to each other after the bolts between the connecting plate and the end block are subsequently loosened.

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