A construction method for vertical assembly and rotation of arch ribs

Abstract

The present invention provides a method for vertical assembly and rotation of an arch rib, comprising the following steps: construction of a fixing foundation for a lowering cable and a fixing foundation for a wind cable; vertical assembly of arch rib segments, installation of lowering cables and wind cables, and pre-tightening; rotation construction: coordinated adjustment of the length of the lowering cables and wind cables, so that the lower end of the arch rib segment is axially centered on a rotatable structure, and the upper part is rotated downward to reach a designed position. By adopting the construction method of the present invention, the rotation construction of the arch rib can be completed without setting up a bracket in the water, thereby avoiding the impact on the passage of waterways and flood discharge, and effectively shortening the construction period.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, in particular to a method for vertically assembling and rotating an arch rib. Background Art

[0002] With the development of society, the structure and shape of bridges are becoming more and more diverse. Steel tube concrete arch bridges are widely used in modern bridge construction due to their unique structure, beautiful shape, strong bearing capacity and other advantages. The main arch rib of the steel tube concrete arch bridge adopts steel tube concrete structure. The construction of the steel tube concrete structure is generally to build the steel tube structure first, and then fill the steel tube with concrete. Due to the radial constraint of the steel tube, the expansion of the compressed concrete is limited, so that the concrete is in a three-dimensional compression state, thereby significantly improving the compressive strength of the concrete.

[0003] At present, the vertical rotation construction of steel tube arch bridges is mostly horizontal assembly and vertical assembly. When assembling, horizontal assembly brackets need to be set up. For example, the invention patent application CN118375076 A discloses a construction method for vertical rotation of arch ribs using rigid jacking. It is necessary to pre-install the main beam bracket, main beam, arch foot and arch rib bracket, and place a pair of arch ribs on the arch rib bracket on that side to support the arch ribs. Then the corresponding vertical rotation construction operation can be carried out. After the operation is completed, the main beam bracket and arch rib bracket need to be removed. However, if the bridge site is located in a river, it is necessary to set up brackets in the water, which will affect the navigation and flood discharge to a certain extent. If the bridge site happens to be located in a valley area, there will be a problem that the bracket height is too high, resulting in difficulty in erection, which will lead to an extension of the construction period. Therefore, in order to solve the above problems, it is very necessary to study a new vertical rotation construction method. Summary of the invention

[0004] The present invention provides a method for vertically assembling and rotating an arch rib, which can complete the rotation construction of the arch rib without setting up a support in water, thereby avoiding the impact on waterway passage and flood discharge, and effectively shortening the construction period.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A method for vertically assembling and rotating an arch rib comprises the following steps:

[0007] Construction of the fixing foundation for the lowering cable and the fixing foundation for the wind cable: The fixing foundation for the lowering cable is completed behind the arch seat in advance, and the fixing foundation for the wind cable is completed in front of the arch seat;

[0008] Assembling arch rib segments and installing lowering cables and wind-catching cables: installing a rotatable structure at the lower end of the arch rib segment closest to the arch seat and connecting it to the arch seat, and then assembling the arch rib segments on one side of the arch rib vertically upward in sequence until the designed length is reached; during the vertical assembly process, or after the vertical assembly is completed, installing and pre-tightening lowering cables at the rear of the arch rib segment in the rotation direction, wherein the length of the lowering cables is adjustable, one end of which is connected to the lowering cable fixing foundation, and the other end is connected to the arch rib segment; installing and pre-tightening wind-catching cables at the front and lower part of the arch rib segment in the rotation direction, wherein the length of the wind-catching cables is adjustable, one end of which is connected to the wind-catching cable fixing foundation, and the other end is connected to the arch rib segment;

[0009] Rotation construction: coordinate and adjust the length of the lowering cables and wind cables so that the lower end of the arch rib segment takes the rotatable structure as the axis and the upper part rotates downward to reach the designed position.

[0010] Preferably, a tensioning jack is provided on the top of the lowering cable fixing foundation, and one end of the lowering cable is connected to the lowering cable fixing foundation through the tensioning jack; a front anchoring jack is provided on the wind-catching cable fixing foundation, and one end of the wind-catching cable is connected to the wind-catching cable fixing foundation through the front anchoring jack.

[0011] Preferably, the lowering cable fixing foundation includes a vertical tower, a first pedestal and a first pile foundation, the first pedestal is fixed on the top of the first pile foundation, at least two first pedestals are provided, and the vertical tower is fixed on them, the vertical tower includes columns and transverse connections, at least two columns are provided, each corresponding to one of the first pedestals is connected, the columns are arranged along the width direction of the arch rib, and adjacent columns are connected with at least two transverse connections at intervals.

[0012] Preferably, two groups of first tensioning jacks and second tensioning jacks are symmetrically fixed on both sides of the top of the lowering cable fixing foundation, and the lowering cable includes a first lowering cable and a second lowering cable; the two groups of the first tensioning jacks are respectively connected to one end of the first lowering cable, and the other ends of the first lowering cable are respectively connected to the middle and upper parts of the arch rings on the same side of the arch rib segment; the two groups of the second tensioning jacks are respectively connected to one end of the second lowering cable, and the other ends of the second lowering cables are respectively connected to the middle and lower parts of the arch rings on the same side of the arch rib segment.

[0013] Preferably, a rear anchor device is further provided behind the lowering cable fixing foundation, and the rear anchor device is connected to the top of the lowering cable fixing foundation through an anchor cable;

[0014] During the construction of the fixing foundation for the lowering cable and the fixing foundation for the wind-catching cable, the construction of the rear anchor device is completed, and the anchor cable is connected and pre-tightened between the rear anchor device and the fixing foundation for the lowering cable.

[0015] Preferably, the rear anchor device includes a second pedestal and a second pile foundation, a second pedestal is fixed on the top of the second pile foundation, at least two second pedestals are arranged, and a rear anchor jack is fixed on the top, the rear anchor jack is connected to one end of the anchor cable, and the other end of the anchor cable is connected to the top of the wind cable fixing foundation on the same side as it.

[0016] Preferably, the wind cable fixing foundation comprises a third cap and a third pile foundation, a third cap is fixed on the top of the third pile foundation, at least two third caps are provided, and are lower than the connection position between the lowering cable and the arch rib segment;

[0017] The top of the third pedestal is provided with front anchoring jacks, and the front anchoring jacks include two groups of first front anchoring jacks and two groups of second front anchoring jacks, and the wind cables include first wind cables and second wind cables; a group of the first front anchoring jacks and a group of the second front anchoring jacks are fixed on the top of each of the third pedestals, the two groups of the first front anchoring jacks are respectively connected to one end of the first wind cables, and the other ends of the first wind cables are respectively connected to the middle and upper parts of the arch rings on the same side of the arch rib segment; the two groups of the second front anchoring jacks are respectively connected to one end of the second wind cables, and the other ends of the second wind cables are respectively connected to the middle and lower parts of the arch rings on the same side of the arch rib segment.

[0018] Preferably, during the assembly of arch rib segments and the rotation construction, a monitoring system is used to monitor the position and line shape of the arch ribs. The monitoring system includes a 4D laser point cloud acquisition device and a lowering control system. The lowering control system is electrically connected to the 4D laser point cloud acquisition device, the lowering cable and the wind cable. The 4D laser point cloud acquisition device is installed in front of and behind the arch rib segment to collect data including the position coordinates and line shape of the arch rib segment, and transmit it to the lowering control system. The lowering control system controls the length and cable force of the lowering cable and the wind cable to control the installation position and lowering position of the arch rib segment within an error range.

[0019] Preferably, after installing the rotatable structure, a temporary fixing structure is installed at the front and rear of the lower end of the arch rib segment closest to the arch seat to fix the arch rib segment closest to the arch seat together;

[0020] Before the rotation construction, the temporary fixed structure is dismantled.

[0021] Preferably, before assembling the arch rib segments and installing the lowering cables and wind-catching cables, the construction of the rear anchor device, the lowering cable fixing foundation, and the wind-catching cable fixing foundation are completed in advance, and the anchor cable is connected and pre-tightened between the rear anchor device and the lowering cable fixing foundation.

[0022] Preferably, before the temporary fixed structure is dismantled, a force unloading device is installed under and on the side of the arch rib; the force unloading device includes a reverse jacking mechanism and a jacking mechanism, the reverse jacking mechanism includes a rigid support structure, one end of which can match and support the outer side surface of the temporary anchoring state position of the bottom of the upper chord of the arch rib, and the other end is fixed on the arch seat, the jacking mechanism includes an upper sealing plate, a lower sealing plate and a jacking jack group, the upper sealing plate is used to match and be fixedly connected with the bottom surface of the lower chord of the arch rib, the lower sealing plate is used to be fixedly connected with the top surface of the temporary fixed structure temporarily anchored under the lower chord of the arch rib and completed with cutting and separation, and a jacking jack group is matched and fixed between the upper sealing plate and the lower sealing plate;

[0023] Before releasing the temporary fixed structure, fix the rigid support structure on the outside of the upper chord of the arch rib so that its top is tightly fitted with the outer side of the upper chord of the arch rib; after releasing the connection between each lower chord of the arch rib and the temporary fixed structure, weld the upper cover plate and the lower cover plate to the bottom of the lower chord of the arch rib and the top surface of the temporary fixed structure that has been cut and separated, respectively, place the jacking jack group and lift it to the corresponding height, and support the lower chord of the arch rib by the jacking jack group. After all the connections between the lower chord of the arch rib and the temporary fixed structure are released and the jacking device is installed, adjust the jacking height of the jacking jack group so that it coordinates with the lowering cable and the wind cable to control the slow lowering of the arch rib.

[0024] The above-mentioned construction method of vertical assembly and rotation of arch ribs has the following advantages:

[0025] (1) In the present invention, since the arch rib segments are installed vertically, there is no need to erect supports in the water, thereby avoiding the impact on the passage of waterways and flood discharge. It also solves the problem of difficulty in erecting supports in valley areas due to their excessive height. At the same time, it can effectively shorten the construction period and reduce the construction cost of erecting supports.

[0026] (2) The present invention adopts a cable system that combines wind cables and lowering cables. By pre-tightening each cable in advance, it can prevent the arch rib from tilting backward due to the longitudinal wind load at the moment of lowering, thereby increasing the stability of its vertical assembly.

[0027] (3) The present invention further combines the use of a temporary fixing structure and a rear anchoring structure, which can further ensure the stability of the vertical assembly of the arch rib segments and better ensure the safety of the rotation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of building a rear anchor device, a lowering cable fixing foundation and a wind cable fixing foundation in the construction method of the present invention.

[0029] Figure 2 It is a schematic diagram of installing a rotatable structure at the lower end of the arch rib segment closest to the arch seat and connecting it to the arch seat in the construction method of the present invention.

[0030] Figure 3 It is a schematic diagram of assembling the arch rib segments on one side to reach the designed length in the construction method of the present invention.

[0031] Figure 4 It is a schematic diagram after the temporary fixed structure is removed in the construction method of the present invention.

[0032] Figure 5 It is a schematic diagram of the arch rib segment rotating to reach the designed position in the construction method of the present invention.

[0033] Figure 6 This is a schematic diagram of an embodiment after the force unloading device is installed before the temporary fixed structure is dismantled.

[0034] Figure 7 It is a structural diagram of the anti-top mechanism.

[0035] Figure 8 It is a structural diagram of the jacking mechanism.

[0036] In the figure, a rear anchor device 100, a second cap 101, a second pile foundation 102, a lower cable fixing foundation 200, a first cap 201, a first pile foundation 202, a vertical turret 203, an arch seat 300, a rotatable structure 400, a lower hinge 401, an upper hinge 402, a rotating shaft 403, a wind cable fixing foundation 500, a third cap 501, a third pile foundation 502, a temporary fixing structure 600, a rear temporary fixing structure 601, a front temporary fixing structure 602, an arch rib segment 700, a ladder cage 800, an arch rib bracket 900, a tensioning jack 1000, a first tensioning jack 1001, a second tensioning jack 1002, a rear anchoring jack 1100, a front anchoring jack 1200, and a first front anchoring jack 1201 , second front anchoring jack 1202, lowering cable 1300, first lowering cable 1301, second lowering cable 1302, wind cable 1400, first wind cable 1401, second wind cable 1402, anchoring cable 1500, arch rib upper chord 1600, anti-jacking mechanism 1700, embedded steel plate 1701, rigid support plate 1702, cushion steel plate 1703, arch rib lower chord 1800, lifting mechanism 1900, upper sealing plate 1901, lifting jack group 1902, lower sealing plate 1903. DETAILED DESCRIPTION

[0037] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to the following embodiments. Example 1

[0038] A method for vertically assembling and rotating an arch rib comprises the following steps:

[0039] Construction of the lowering cable fixed foundation 200 and the wind cable fixed foundation 500: combined Figure 1 As shown, the construction of the lowering cable fixing foundation 200 is completed behind the arch seat 300 in advance, and the construction of the wind cable fixing foundation 500 is completed in front of the arch seat 300; there is no strict requirement for the construction sequence of the arch seat 300, the lowering cable fixing foundation 200, and the wind cable fixing foundation 500, which can be carried out simultaneously, alternately, or in a certain sequence, as long as they are completed before the next step starts.

[0040] Assemble the arch rib segments 700 and install the lowering cables 1300 and the wind cables 1400: Figure 2 As shown, a rotatable structure 400 is installed at the lower end of the arch rib segment 700 closest to the arch seat 300 to connect with the arch seat 300. Of course, the arch seat 300 is also provided with corresponding embedded parts to realize the connection of the arch rib segment 700. Then, the arch rib segments 700 on one side of the arch rib are assembled vertically upward in sequence until the designed length is reached, that is, Figure 3 In the state shown, since the arch rib segment 700 is installed vertically, there is no need to set up a bracket in the water. During the assembly process of the arch rib segment 700, the arch rib segment 700 can be hoisted section by section by a large crane, and then welded with the previous arch rib segment 700 after being hoisted into place; during the vertical assembly process, or after the vertical assembly is completed, the lowering cable 1300 is installed and pre-tightened at the rear of the arch rib segment 700 in the rotation direction, and the length of the lowering cable 1300 is adjustable, one end of which is connected to the lowering cable fixing base 200, and the other end is connected to the arch rib segment 700; the wind-catching cable 1400 is installed and pre-tightened at the front and lower part of the arch rib segment 700 in the rotation direction, and the length of the wind-catching cable 1400 is adjustable, one end of which is connected to the wind-catching cable fixing base 500, and the other end is connected to the arch rib segment 700. The lowering cables 1300 and the wind-catching cables 1400 are pre-tightened to prevent the arch rib segment 700 from tilting backward due to the longitudinal wind load at the moment of lowering, thereby increasing the stability of its vertical assembly.

[0041] Rotation construction: coordinate and adjust the length of the lowering cable 1300 and the wind cable 1400, so that the lower end of the arch rib segment 700 rotates downward to the designed position with the rotatable structure 400 as the axis, that is, Figure 5 In the state shown, after the rotation reaches the designed position, the wind catching rope 1400 is removed first.

[0042] Subsequently, the arch rib segments can be aligned with reference to the existing technology. If the arch rib segment 700 on the other side has been installed in place, it is also necessary to complete the welding and fixation of the arch rib segment 700 that has been rotated into place and the arch rib segment 700 on the other side, and then complete the connection between the arch rib segment 700 and the arch seat 300, or first complete the connection between the arch rib segment 700 that has been rotated into place and the arch seat 300, and then complete the alignment connection between the arch rib segments 700 on both sides, and finally remove the lowering cable 1300.

[0043] Preferably, a tensioning jack 1000 is provided on the top of the lowering cable fixing foundation 200, and one end of the lowering cable 1300 is connected to the lowering cable fixing foundation 200 through the tensioning jack 1000; a front anchoring jack 1200 is provided on the wind-catching cable fixing foundation 500, and one end of the wind-catching cable 1400 is connected to the wind-catching cable fixing foundation 500 through the front anchoring jack 1200. By providing the jacks, the lengths of the lowering cable 1300 and the wind-catching cable 1400 can be better adjusted.

[0044] Preferably, this embodiment provides a specific structure of a lowering cable fixing foundation 200, wherein the lowering cable fixing foundation 200 includes a vertical rotating tower 203, a first pedestal 201 and a first pile foundation 202, wherein the first pedestal 201 is fixed on the top of the first pile foundation 202, and the vertical rotating tower 203 is fixed on the first pedestal 201, and the vertical rotating tower 203 includes columns and transverse connections, wherein at least two columns are provided, and each column is connected to one of the first pedestals 201, and the columns are arranged along the width direction of the arch rib, and at least two transverse connections are connected between the columns at intervals. The first pile foundation 202 can be made of 4 reinforced concrete pile foundations, which are located at the four corners of the bottom of the first pedestal 201 and can be constructed in a conventional manner, and embedded parts are provided in the first pedestal 201, which can be connected to the vertical rotating tower 203 to ensure the stability of the vertical rotating tower 203. For the columns, a steel pipe structure can be used. The positions of the two columns correspond to the positions of the left arch ring and the right arch ring of the arch rib segment respectively, and the spacing matches the spacing between the left arch ring and the right arch ring, that is, the same or slightly larger or smaller than the spacing between the left arch ring and the right arch ring. The two columns are connected by a transverse connection, which makes the vertical tower 203 a whole. The transverse connection can adopt a truss structure.

[0045] Preferably, two groups of first tensioning jacks 1001 and second tensioning jacks 1002 are symmetrically fixed on both sides of the top of the lowering cable fixing foundation 200, and the lowering cable 1300 includes a first lowering cable 1301 and a second lowering cable 1302; the two groups of first tensioning jacks 1001 are respectively connected to one end of the first lowering cable 1301, and the other ends of the first lowering cable 1301 are respectively connected to the middle and upper parts of the arch rings on the same side of the arch rib segment 700; the two groups of second tensioning jacks 1002 are respectively connected to one end of the second lowering cable 1302, and the other ends of the second lowering cable 1302 are respectively connected to the middle and lower parts of the arch rings on the same side of the arch rib segment 700. In combination with the present embodiment, a lowering cable fixing foundation 200 including a vertical rotating tower 203 is adopted, and a group of first tensioning jacks 1001 and a group of second tensioning jacks 1002 are respectively fixed on the top of each column, and are symmetrically arranged relative to the vertical center line of the vertical rotating tower 203. Each group of tensioning jacks 1000 may include one or more jacks, which are arranged according to the load-bearing requirements. The first tensioning jack 1001 and the second tensioning jack 1002 can be fixed by an anchor box, and the anchor box is welded or bolted to the vertical rotating tower 203. The use of the anchor box can increase the strength of the tensioning jack 1000. The connection between the first lowering cable 1301 and the second lowering cable 1302 and the arch ring can also be achieved by anchors. The lowering cable 1300 is generally connected to the upper chord 1600 of the arch rib of the arch ring.

[0046] Preferably, a rear anchor device 100 is further provided behind the lowering cable fixing foundation 200, and the rear anchor device 100 is connected to the top of the lowering cable fixing foundation 200 through an anchor cable 1500. The rear anchor device 100 can better ensure the stability of the vertical rotation tower 203 during the tensioning process of the lowering cable 1300. During the construction of the lowering cable fixing foundation 200 and the wind cable fixing foundation 500, the construction of the rear anchor device 100 is completed, and the anchor cable 1500 is connected and pre-tightened between the rear anchor device 100 and the lowering cable fixing foundation 200. There is no strict requirement for the construction sequence of the rear anchor device 100 and the arch seat 300, the lowering cable fixing foundation 200, and the wind cable fixing foundation 500. They can be carried out simultaneously, alternately, or in a certain order. However, the construction of the rear anchor device 100 is generally completed before the construction of the vertical rotation tower 203 is completed to facilitate the installation of the anchor cable 1500.

[0047] Preferably, the rear anchor device 100 includes a second cap 101 and a second pile foundation 102, the second cap 101 is fixed on the top of the second pile foundation 102; at least two second caps 101 are provided, and a rear anchor jack 1100 is fixed on the top, the rear anchor jack 1100 is connected to one end of the anchor cable 1500, and the other end of the anchor cable 1500 is connected to the top of the wind cable fixed foundation 500 on the same side. In this embodiment, the second pile foundation 102 adopts two reinforced concrete pile foundations, and embedded parts are provided in the second cap 101 to facilitate connection with the rear anchor jack 1100. The rear anchor jack 1100 is also generally symmetrically provided in two groups, which are respectively connected to the top of the column on the same side as it, and the rear anchor jack 1100 can be fixed by an anchor box, and the other end of the anchor cable 1500 can also be connected to the wind cable fixed foundation 500 by an anchor.

[0048] Preferably, the wind cable fixing foundation 500 includes a third pedestal 501 and a third pile foundation 502. The third pedestal 501 is fixed on the top of the third pile foundation 502. There are at least two third pedestals 501, which are lower than the connection position between the lowering cable 1300 and the arch rib segment 700. In this embodiment, the arch rib segment 700 on the other side of the arch rib, i.e. Figure 3 In the direction shown, the arch rib segment 700 on the right has been pre-installed on the arch rib bracket 900. The arch rib segment 700 on the right is basically constructed on land, but the arch rib segment farthest from the right arch seat is located above the river. In order to build the arch rib bracket 900 corresponding to support the arch rib segment, the third pedestal 501 and the third pile foundation 502 need to be installed in advance. This embodiment uses the existing third pedestal 501 and the third pile foundation 502 as the wind cable fixing foundation 500. A front anchoring jack 1200 is arranged on the top of the third pedestal 501, and the front anchoring jack 1200 includes two groups of first front anchoring jacks 1201 and two groups of second front anchoring jacks 1202. The wind rope 1400 includes a first wind rope 1401 and a second wind rope 1402. A group of first front anchoring jacks 1201 and a group of second front anchoring jacks 1202 are fixed on the top of each third pedestal 501. The two groups of first front anchoring jacks 1201 are connected to the first and second front anchoring jacks 1202 respectively. The first wind rope 1401 is connected to one end of the first wind rope 1401, and the other end of the first wind rope 1401 is respectively connected to the middle and upper part of the arch ring on the same side of the arch rib segment 700; the two groups of second front anchoring jacks 1202 are respectively connected to one end of the second wind rope 1402, and the other end of the second wind rope 1402 is respectively connected to the middle and lower part of the arch ring on the same side of the arch rib segment 700. By setting two layers of wind ropes 1400, it is better to prevent the arch rib from tilting back due to the longitudinal wind load at the moment of lowering. The wind rope 1400 is generally connected to the arch rib lower chord 1800 of the arch ring.

[0049] Preferably, the rotatable structure 400 includes an upper hinge 402, a lower hinge 401 and a rotating shaft 403. The upper portion of the upper hinge 402 is connected to the lower end of the arch rib segment 700, and the lower portion of the lower hinge 401 is connected to the arch seat 300. The upper hinge 402 and the lower hinge 401 are rotatably connected via the rotating shaft 403. In this embodiment, the rotatable structure 400 is provided with two groups, which are respectively installed at Figure 2 The front and rear of the middle of the bottom end of the rib segment 700 in the direction shown correspond to the middle of the bottom ends of the left arch ring and the right arch ring, respectively.

[0050] Preferably, during the process of assembling the arch rib segments and rotating the structure, a monitoring system is used to monitor the position and line type of the arch ribs. The monitoring system includes a 4D laser point cloud acquisition device and a lowering control system. The lowering control system is electrically connected to the 4D laser point cloud acquisition device, the lowering cable 1300 and the cable wind cable 1400. The 4D laser point cloud acquisition device is installed in front of and behind the arch rib segment 700 to collect data including the position coordinates and line type of the arch rib segment and transmit it to the lowering control system. The lowering control system transmits the lowering instruction to control the length and cable force of the lowering cable 1300 and the cable wind cable 1400, so that the installation position and lowering position of the arch rib segment are controlled within the error range. During the process of assembling the arch rib segment 700, the hoisting position of the arch rib segment 700 can be understood through the 4D laser point cloud acquisition device to assist in adjusting the hoisting position. During the rotation construction process, according to the feedback from the 4D laser point cloud acquisition device, the lowering control system controls the tension of the lowering cable 1300 and the cable wind cable 1400 by controlling the tensioning jack 1000 and the front anchoring jack 1200 to adjust the position of the arch rib segment 700. Of course, in order to facilitate the stable vertical rotation of the tower, the rear anchoring jack 1100 is also connected to the lowering control system, and the cable tension of the anchoring cable 1500 can also be controlled by the lowering control system. The 4D laser point cloud acquisition device can be installed on both sides of the river. The images collected by the 4D laser point cloud acquisition device need to be converted into a coordinate system after collection to obtain the position coordinates of the arch rib segment 700. This conversion can be achieved using existing technology.

[0051] Preferably, after the rotatable structure 400 is installed, a temporary fixing structure 600 is installed at the front and rear of the lower end of the arch rib segment 700 closest to the arch seat 300 to fix the arch rib segment 700 closest to the arch seat 300 together with the arch seat 300, that is, Figure 2In the direction shown, the left and right sides of the bottom end of the arch rib segment 700 are generally fixed together with the arch seat 300 by welding steel pipes. Of course, the arch seat 300 is provided with corresponding embedded parts to connect with the steel pipes. The temporary fixing structure 600 includes a rear temporary fixing structure 601 and a front temporary fixing structure 602. The rear temporary fixing structure 601 is connected to the arch rib upper chord 1600, and the front temporary fixing structure 602 is connected to the arch rib lower chord 1800. Before the rotation construction, the temporary fixing structure 600 is removed, that is, Figure 4 This embodiment only lists one temporary fixing structure 600 that is convenient for installation, and other temporary fixing structures 600 may also be used, as long as they are sufficient to fix the arch rib segment 700.

[0052] In addition, regarding the time node of the installation of the lowering cable 1300 and the cable wind cable 1400, it is preferred that after the arch rib segment 700 correspondingly connected to the lowering cable 1300 and the wind cable 1400 is installed, the lowering cable 1300 is connected to the arch rib segment 700 and the lowering cable fixing base 200, and the wind cable 1400 is connected to the arch rib segment 700 and the wind cable fixing base 500. This can better ensure the stability of the arch rib segment 700 during installation, reduce construction risks, and reduce the position deviation of the arch rib segment 700 caused by airflow. Preferably, when the arch rib segments 700 are vertically assembled, in order to facilitate welding between the arch rib segments 700, the construction of the ladder cage 800 is also carried out at the same time. The ladder cage 800 has stairs to facilitate construction workers to climb up and down, and there are fences around to prevent construction workers from falling. The ladder cage 800 is also assembled section by section, matching the assembly height of the arch rib segments 700. Each time a ladder cage 800 is built, a welding work platform is installed on one side of the top around the outer periphery of the arch rib segment 700, so that the welding construction of the next arch rib segment can be carried out on the welding work platform. After the welding of the next arch rib segment is completed, another ladder cage 800 is built and the welding work platform is installed, and the above operation is repeated until the arch rib segment 700 reaches the designed height. Before the rotation construction, the ladder cage 800 and the welding work platform are removed.

[0053] Based on the above preferred technical solutions and in combination with the geographical environment of the construction application of this embodiment, the specific steps of this embodiment include:

[0054] Construction of the lowering cable fixing foundation 200, the wind cable fixing foundation 500, and the rear anchor device 100: Figure 1As shown, the construction of the lowering cable fixing foundation 200 and the rear anchor device 100 is completed in advance behind the arch seat 300, and the construction of the wind cable fixing foundation 500 is completed in front of the arch seat 300; in this embodiment, the wind cable fixing foundation 500 directly uses the third pedestal 501 under the arch rib bracket 900 of the other side arch rib segment 700 closest to the lowering cable fixing foundation 200, which can save construction costs; there is no strict requirement for the construction sequence of the arch seat 300, the lowering cable fixing foundation 200, the wind cable fixing foundation 500, and the rear anchor device 100, which can be carried out simultaneously, alternately, or in a certain order, as long as they are completed before the next step starts. A tensioning jack 1000, a front anchoring jack 1200 and a rear anchoring jack 1100 are installed on the top of the lowering cable fixing foundation 200, the wind cable fixing foundation 500 and the rear anchor device 100 respectively, and an anchoring cable 1500 is connected and pre-tightened between the rear anchoring jack 1100 and the top of the lowering cable fixing foundation 200.

[0055] Assemble the arch rib segments 700 and install the lowering cables 1300 and the wind cables 1400: Figure 2 As shown, a rotatable structure 400 is installed at the lower end of the arch rib segment 700 closest to the arch seat 300 to connect with the arch seat 300, and an embedded part is correspondingly provided in the arch seat 300 to connect with the lower hinge 401, and the upper hinge 402 is welded to the lower end of the arch rib segment 700 closest to the arch seat 300, and is connected with the lower hinge 401 through the rotating shaft 403. At the same time, a temporary fixing structure 600 is welded to the lower end of the arch rib segment 700 closest to the arch seat 300, and the lower end of the temporary fixing structure 600 is also connected to the embedded part embedded in the arch seat 300, so that the arch rib segment 700 closest to the arch seat 300 is fixed; then, with the help of a large crane, the arch rib segments 700 on one side of the arch rib are assembled vertically upward in sequence until the designed length is reached, that is, Figure 3 In the state shown, adjacent arch rib segments 700 are connected by welding; during the vertical assembly process, or after the vertical assembly is completed, a lowering cable 1300 is installed and pre-tightened at the rear of the arch rib segment 700 in the rotation direction, and the length of the lowering cable 1300 is adjustable, one end of which is connected to the tensioning jack 1000, and the other end is connected to the arch rib segment 700; a wind-catching cable 1400 is installed and pre-tightened at the front and lower part of the arch rib segment 700 in the rotation direction, and one end of the wind-catching cable 1400 is connected to the front anchoring jack 1200, and the other end is connected to the arch rib segment 700.

[0056] Rotation construction: Figure 4 As shown, the temporary fixed structure 600 is removed, and the lengths of the lowering cable 1300 and the wind cable 1400 are adjusted by the tensioning jack 1000 and the front anchoring jack 1200, so that the lower end of the arch rib segment 700 is rotated downward with the rotatable structure 400 as the axis to reach the designed position, that is, Figure 5In the state shown, after the rotation reaches the designed position, the wind cable 1400 is first removed. The arch rib segments can be aligned with the prior art later. In this embodiment, the welding and fixation of the arch rib segment 700 on the other side also requires the completion of the welding and fixation of the arch rib segment 700 rotated in place and the arch rib segment 700 on the other side, and then the connection of the arch rib segment 700 and the arch seat 300 is completed, or the connection of the arch rib segment 700 rotated in place and the arch seat 300 is completed first, and then the alignment connection between the arch beam segments 700 on both sides is completed, and finally the lowering cable 1300 is removed. Example 2

[0057] At the moment when the arch rib is vertically rotated and lowered to release the temporary fixed structure and the arch rib connection support, a large instantaneous force will be generated, causing the lowering cable 1300 and the vertical tower 203 to be suddenly stressed, and then the cable force of the lowering system may not be controlled, resulting in the arch rib being instantly unstable. In order to solve the above possible problems, combined with Figure 6 As shown, this embodiment is based on the embodiment 1, and a force unloading device is added. Before the temporary fixed structure is removed, the force unloading device is installed under and on the side of the arch rib; specifically:

[0058] The unloading device includes an anti-lifting mechanism 1700 and a lifting mechanism 1900, Figure 7 As shown, the anti-lift mechanism 1700 includes a rigid support structure, one end of which can match and support the outer side surface of the temporary anchoring state position at the bottom of the arch rib upper chord 1600 (the outer side surface here refers to the other side surface away from the arch rib lower chord 1800), and the other end is fixed on the arch seat. The anti-lift mechanism 1700 forms a rigid support for the arch rib upper chord 1600 by using the reaction force of the arch seat 3, thereby effectively preventing the arch rib upper chord 1600 from tilting backward. Figure 8As shown, the lifting mechanism 1900 includes an upper sealing plate 1901, a lower sealing plate 1903 and a lifting jack group 1902. The upper sealing plate 1901 is used to match and fix with the bottom surface of the arch rib lower chord 1800, and the lower sealing plate 1903 is used to fix with the top surface of the temporary fixed structure temporarily anchored under the arch rib lower chord 1800 and completed cutting and separation. The lifting jack group 1902 is matched and fixed between the upper sealing plate 1901 and the lower sealing plate 1903; it should be noted that when the connection between the arch rib lower chord 1800 and the temporary fixed structure is released, the temporary fixed structure is generally A certain length will be cut so that the arch rib lower chord 1800 maintains a certain distance from the temporary fixed structure. When the first arch rib lower chord 1800 is disconnected from the temporary fixed structure, the connection between other arch rib lower chords 1800 and the temporary fixed structure is relied on to keep the position of the arch rib unchanged, thereby ensuring the safety of the installation of the jacking mechanism 1900. When the last arch rib lower chord 1800 is disconnected from the temporary fixed structure, the support of the temporary fixed structure and the jacking mechanism 1900 to other arch rib lower chords 1800 is relied on to ensure the safety of the installation of the last jacking mechanism 1900.

[0059] Before releasing the temporary fixing structure, fix the rigid support structure to the outside of the arch rib upper chord 1600 so that its top is tightly fitted with the outer side of the arch rib upper chord 1600, and then release the rear temporary fixing structure 601 connected to the arch rib upper chord 1600; next release the connection between the arch rib lower chord 1800 and the front temporary fixing structure 602, and after releasing the connection between each arch rib lower chord 1800 and the rear temporary fixing structure 601, weld the upper sealing plate 1901 and the lower sealing plate 1903 to the arch rib lower chord 1800, respectively. 00 below and on the top surface of the temporary fixed structure that has been cut and separated, place the lifting jack group 1902 and lift it to the corresponding height. The arch rib lower chord 1800 is supported by the lifting jack group 1902. After all the connections between the arch rib lower chord 1800 and the front temporary fixed structure 602 are released and the lifting device is installed, at this time, the connection between the temporary fixed structure and the arch rib segment 700 has been completely released, and the lifting height of the lifting jack group 1902 is adjusted to coordinate with the lowering cable and the wind cable 1400 to control the arch rib to be slowly lowered.

[0060] This embodiment has also made further optimizations for the unloading device. This embodiment provides a specific structure of a rigid support structure, which includes a wedge-shaped pad, the shape of which can better fit the arch seat 3 and the arch rib upper chord 1600, and form support for the arch rib upper chord 1600; the wedge-shaped pad includes a plurality of rigid support plates 1702 arranged at intervals, and the rigid support plates 1702 are arranged along the width direction of the arch rib to support the arch rib upper chord 1600 with a certain width, and one end of each rigid support plate 1702 can match the outer side surface of the temporary anchoring state position at the bottom end of the arch rib upper chord 1600, and the other end is fixed on the arch seat 3; the number of wedge-shaped pads generally matches the number of arch rib upper chords 1600, that is, each arch rib upper chord 1600 is matched with a wedge-shaped pad support. More preferably, in order to ensure the supporting force for the arch rib upper chord 1600, the rigid support plate 1702 is made of steel plate, and the thickness is preferably not less than 20 mm.

[0061] For the installation of the rigid support plate 1702, it is preferred to set up an embedded steel plate 1701. The embedded steel plate 1701 is embedded in the arch seat 3 when the arch seat 3 is cast. The top is exposed from the arch seat 3 and connected to the other end of the rigid support plate 1702. The connection method is generally welding, which is convenient and quick.

[0062] In addition, the anti-top mechanism may also include a pad steel plate 1703. After the arch rib upper chord 1600 is disconnected from the temporary fixing structure, the pad steel plate 1703 is fixed to the bottom surface of the arch rib upper chord 1600 or the top surface of the corresponding temporary fixing structure; the temporary fixing structure mentioned here refers to the temporary fixing structure correspondingly connected below the arch rib upper chord 1600. Generally, one arch rib upper chord 1600 is provided with a pad steel plate 1703. The connection is generally disconnected by cutting. After cutting, a certain space is left between the arch rib upper chord 1600 and the temporary fixing structure to weld the pad steel plate 1703, so as to increase the contact surface so that the temporary fixing structure can still support the arch rib upper chord 1600. After the other components of the unloading device are installed and before the arch rib is rotated, the pad steel plate 1703 is removed so that the rotation of the arch rib upper chord 1600 is not affected by the pad steel plate 1703.

[0063] Preferably, at least two jacking mechanisms 1900 are provided, matching the number of arch rib lower chords 1800, that is, one jacking mechanism 1900 is matched and installed for each arch rib lower chord 1800. If there are four arch rib lower chords 1800, four jacking mechanisms 1900 are matched and installed.

[0064] Preferably, combined Figure 2As shown, in the lifting mechanism 1900, the lifting jack group 1902 includes at least two jacks, which are arranged along the tilting direction of the arch rib lower chord 1800 after the temporary anchoring is released, so as to support the arch rib lower chord 1800 in a more balanced manner and achieve the purpose of slowly releasing the arch rib lower chord 1800.

[0065] Preferably, the lifting mechanism 1900 also includes a remote control system, which is electrically connected to the lifting jack group 1902. The lifting and lowering of the jacks can be conveniently controlled through the remote control system to ensure the safety of the construction.

[0066] Preferably, since the lifting mechanism 1900 needs to bear a relatively large load, the thickness of the upper sealing plate 1901 and the lower sealing plate 1903 should be not less than 25 mm. In this embodiment, a steel plate with a thickness of 30 mm is selected.

[0067] In response to the above-mentioned more preferred technical solution, the present embodiment also provides a more specific operating method: the embedded steel plate 1701 is installed in advance before the arch seat 3 is cast, and the rigid support structure is welded to the embedded steel plate 1701 before the temporary fixing structure 600 is released, so that the top of the steel plate is tightly fitted with the outer side of the arch rib upper chord 1600, and each arch rib upper chord 1600 is correspondingly installed with a counter-top mechanism 1700 to give the arch rib a reaction force to prevent the arch rib from leaning back at the moment of releasing the temporary fixing structure. In addition, after the connection between the rear end temporary fixing structure 601 and the arch rib upper chord 1600 is released, a pad steel plate 1703 is welded to the bottom surface of the arch rib upper chord 1600 or the top surface of the corresponding rear end temporary fixing structure 601. After the anti-lifting mechanism 1700 is installed, the jacking mechanism 1900 is installed. After each connection between the lower chord 1800 of the arch rib and the front temporary fixed structure 602 is released, the upper sealing plate 1901 and the lower sealing plate 1903 are respectively welded to the bottom of the lower chord 1800 of the arch rib and the top surface of the front temporary fixed structure 602 that has been cut and separated. The jacking jack group 1902 is placed and lifted to the corresponding height. The arch rib lower chord 1800 is supported by the jacking jack group 1902. After all the connections between the lower chord 1800 of the arch rib and the temporary fixed structure are released and the jacking device is installed, at this time, the connection between the temporary fixed structure and the arch rib segment 700 has been completely released, the pad steel plate 1703 is removed, and the jacking jack group 1902 of the four chords is remotely controlled to be synchronously unloaded, and the height is lowered in coordination with the lowering cable 1300 and the cable wind cable 1400, so as to achieve the purpose of slowly releasing the arch rib.

[0068] This embodiment utilizes the anti-lifting mechanism 1700 to prevent the arch rib from tilting backward, and utilizes the lifting mechanism 1900 to maintain the balance of the arch rib and coordinate the slow lowering of the arch rib, which can help reduce the probability of instantaneous instability of the arch rib when the connection support between the temporary fixing structure and the arch rib is released.

Claims

1. A method for vertically assembling and rotating an arch rib, characterized in that The following steps are involved: Construction of the fixing foundation for the lowering cable and the fixing foundation for the wind cable: The fixing foundation for the lowering cable is completed behind the arch seat in advance, and the fixing foundation for the wind cable is completed in front of the arch seat; Assembling arch rib segments and installing lowering cables and wind-catching cables: installing a rotatable structure at the lower end of the arch rib segment closest to the arch seat and connecting it to the arch seat, and then assembling the arch rib segments on one side of the arch rib vertically upward in sequence until the designed length is reached; during the vertical assembly process, or after the vertical assembly is completed, installing and pre-tightening lowering cables at the rear of the arch rib segment in the rotation direction, wherein the length of the lowering cables is adjustable, one end of which is connected to the lowering cable fixing foundation, and the other end is connected to the arch rib segment; installing and pre-tightening wind-catching cables at the front and lower part of the arch rib segment in the rotation direction, wherein the length of the wind-catching cables is adjustable, one end of which is connected to the wind-catching cable fixing foundation, and the other end is connected to the arch rib segment; Rotation construction: coordinate and adjust the length of the lowering cables and wind cables so that the lower end of the arch rib segment takes the rotatable structure as the axis and the upper part rotates downward to reach the designed position; After the rotatable structure is installed, a temporary fixing structure is installed at the front and rear of the lower end of the arch rib segment closest to the abutment to fix the arch rib segment closest to the abutment together with the abutment; Before the rotation construction, the temporary fixed structure is dismantled; Before the temporary fixed structure is dismantled, a force unloading device is installed under and on the side of the arch rib; the force unloading device includes an anti-top mechanism and a jacking mechanism, the anti-top mechanism includes a rigid support structure, one end of the rigid support structure can match and support the outer side surface of the temporary anchoring state position of the bottom of the arch rib upper chord, and the other end is fixed to the arch seat, the jacking mechanism includes an upper sealing plate, a lower sealing plate and a jacking jack group, the upper sealing plate is used to match and be fixedly connected with the bottom surface of the arch rib lower chord, the lower sealing plate is used to be fixedly connected with the top surface of the temporary fixed structure temporarily anchored under the arch rib lower chord and completed with cutting and separation, and a jacking jack group is matched and fixed between the upper sealing plate and the lower sealing plate; Before releasing the temporary fixed structure, fix the rigid support structure on the outside of the upper chord of the arch rib so that its top is tightly fitted with the outer side of the upper chord of the arch rib; after releasing the connection between each lower chord of the arch rib and the temporary fixed structure, weld the upper cover plate and the lower cover plate to the bottom of the lower chord of the arch rib and the top surface of the temporary fixed structure that has been cut and separated, respectively, place the jacking jack group and lift it to the corresponding height, and support the lower chord of the arch rib by the jacking jack group. After all the connections between the lower chord of the arch rib and the temporary fixed structure are released and the jacking device is installed, adjust the jacking height of the jacking jack group so that it coordinates with the lowering cable and the wind cable to control the slow lowering of the arch rib.

2. The method for vertically assembling and rotating arch ribs according to claim 1 is characterized in that: A tensioning jack is arranged on the top of the lowering cable fixing foundation, and one end of the lowering cable is connected to the lowering cable fixing foundation through the tensioning jack; a front anchoring jack is arranged on the wind-catching cable fixing foundation, and one end of the wind-catching cable is connected to the wind-catching cable fixing foundation through the front anchoring jack.

3. The method for vertically assembling and rotating arch ribs according to claim 1 is characterized in that: The lowering cable fixing foundation includes a vertical tower, a first pedestal and a first pile foundation, the first pedestal is fixed on the top of the first pile foundation, at least two first pedestals are provided, and the vertical tower is fixed on them, the vertical tower includes columns and transverse connections, at least two columns are provided, each corresponding to one of the first pedestals is connected, the columns are arranged along the width direction of the arch rib, and adjacent columns are connected with at least two transverse connections at intervals.

4. The method for vertically assembling and rotating an arch rib according to any one of claims 1 to 3, characterized in that: Two groups of first tensioning jacks and second tensioning jacks are symmetrically fixed on both sides of the top of the lowering cable fixing foundation, and the lowering cable includes a first lowering cable and a second lowering cable; the two groups of the first tensioning jacks are respectively connected to one end of the first lowering cable, and the other ends of the first lowering cable are respectively connected to the middle and upper parts of the arch rings on the same side of the arch rib segment; the two groups of the second tensioning jacks are respectively connected to one end of the second lowering cable, and the other ends of the second lowering cables are respectively connected to the middle and lower parts of the arch rings on the same side of the arch rib segment.

5. The method for vertically assembling and rotating an arch rib according to any one of claims 1 to 3, characterized in that: A rear anchor device is also provided behind the lowering cable fixing foundation, and the rear anchor device is connected to the top of the lowering cable fixing foundation through an anchor cable; During the construction of the fixing foundation for the lowering cable and the fixing foundation for the wind-catching cable, the construction of the rear anchor device is completed, and the anchor cable is connected and pre-tightened between the rear anchor device and the fixing foundation for the lowering cable.

6. The method for vertically assembling and rotating arch ribs according to claim 5, characterized in that: The rear anchor device includes a second pedestal and a second pile foundation, a second pedestal is fixed on the top of the second pile foundation, at least two second pedestals are arranged, and a rear anchor jack is fixed on the top, the rear anchor jack is connected to one end of the anchor cable, and the other end of the anchor cable is connected to the top of the lowering cable fixing foundation on the same side as it.

7. The method for vertically assembling and rotating arch ribs according to claim 4, characterized in that: The wind cable fixing foundation comprises a third cap and a third pile foundation, a third cap is fixed on the top of the third pile foundation, at least two third caps are provided, and are lower than the connection position between the lowering cable and the arch rib segment; The top of the third pedestal is provided with front anchoring jacks, and the front anchoring jacks include two groups of first front anchoring jacks and two groups of second front anchoring jacks, and the wind cables include first wind cables and second wind cables; a group of the first front anchoring jacks and a group of the second front anchoring jacks are fixed on the top of each of the third pedestals, the two groups of the first front anchoring jacks are respectively connected to one end of the first wind cables, and the other ends of the first wind cables are respectively connected to the middle and upper parts of the arch rings on the same side of the arch rib segment; the two groups of the second front anchoring jacks are respectively connected to one end of the second wind cables, and the other ends of the second wind cables are respectively connected to the middle and lower parts of the arch rings on the same side of the arch rib segment.

8. The method for vertically assembling and rotating arch ribs according to claim 1, characterized in that: During the process of assembling the arch rib segments and rotating the structure, a monitoring system is used to monitor the position and line shape of the arch ribs. The monitoring system includes a 4D laser point cloud acquisition device and a lowering control system. The lowering control system is electrically connected to the 4D laser point cloud acquisition device, the lowering cable and the wind cable. The 4D laser point cloud acquisition device is installed in front of and behind the arch rib segments to collect data including the position coordinates and line shape of the arch rib segments, and transmit the data to the lowering control system. The lowering control system controls the length and cable force of the lowering cable and the wind cable to control the installation position and lowering position of the arch rib segments within an error range.

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