Vertical connection and lowering method for arch ribs

Abstract

We provide a vertical joining and lowering method for arch ribs. [Solution] The method includes the steps of constructing the sling cable fixing base and the wind cable fixing base, joining the arch rib segments and attaching the sling cables 1300 and wind cable 1400 and applying preload, and performing lowering construction by adjusting the lengths of the sling cables and wind cable so that the lower ends of the arch rib segments 700 rotate downward around the rotatable structure until the upper ends reach the designed position. By adopting the construction method of the present invention, it is possible to complete the lowering construction of the arch rib without erecting underwater supports, avoiding impacts on navigation and flood drainage and effectively shortening the construction period.

Description

[Technical Field]

[0001] The present invention relates to the technical field of bridge construction, and more particularly to a vertical joining and lowering method for arch ribs. [Background technology]

[0002] With the development of society, bridge structures and modeling have become more and more diverse, and steel-tube concrete arch bridges are widely used in modern bridge construction due to their unique structure, beautiful modeling, and strong load-bearing capacity. The main arch rib of a steel-tube concrete arch bridge uses a steel-tube concrete structure, and in the construction of a steel-tube concrete structure, the steel tube structure is generally constructed first, and then concrete is filled into the steel tube. The radial restraint of the steel tube limits the expansion of the concrete under pressure, allowing the concrete to be pressure-bearing in three directions, thereby significantly improving the compressive strength of the concrete.

[0003] Currently, most vertical lowering methods for steel pipe arch bridges use horizontal joints and vertical pulling, which require the installation of horizontal joint supports during installation. Patent application CN118375076A discloses a method for vertically rotating the arch rib using a rigid lifting device. The main beam support, main beam, arch support, and arch rib support are installed first, and each pair of arch ribs is attached to its corresponding arch rib support to support the arch rib. After the vertical rotation, the main beam support and arch rib support can be removed. However, if the bridge is located in a river and supports are installed underwater, this can have a significant impact on navigation and flood discharge. If the bridge is located in a mountain valley, the support height can be too high, making erection difficult and lengthening the construction period. Therefore, research into new vertical lowering methods is needed to solve these problems. Summary of the Invention [Means for solving the problem]

[0004] The present invention provides a method for vertically joining and lowering arch ribs, which allows the rotation of arch ribs to be completed without erecting underwater supports, thereby avoiding the impact on waterway traffic and flood discharge and effectively shortening the construction period.

[0005] In order to achieve the above object, the present invention employs the following technical means: A vertical joining and lowering method for arch ribs, A step of constructing a suspension cable fixing base and a wind-resistant cable fixing base, in which the construction of the suspension cable fixing base is completed in advance behind the arch support and the construction of the wind-resistant cable fixing base is completed in front of the arch support; a step of joining the arch rib segments and attaching the slings and wind-resistant cables, in which a rotatable structure is attached to the lower end of the arch rib segment closest to the arch support and connected to the arch support, and then the arch rib segments on one side of the arch rib are joined vertically upward one after another until they reach a predetermined length, and during or after the vertical joining is completed, a sling cable is attached to the rear of the arch rib segment in the rotational direction to apply preload, the sling cable having an adjustable length, one end connected to the sling cable fixed base and the other end connected to the arch rib segment, and a wind-resistant cable is attached to the front and below the rotational direction of the arch rib segment to apply preload, the wind-resistant cable having an adjustable length, one end connected to the wind-resistant cable fixed base and the other end connected to the arch rib segment; and a step of performing lowering construction, in which the lower end of the arch rib segment is centered on the rotatable structure and the lengths of the suspension ropes and wind-resistant ropes are adjusted so that the upper end rotates downward until it reaches the designed position.

[0006] Preferably, a tensioning jack is provided on the top of the suspension rope fixing base, one end of the suspension rope is connected to the suspension rope fixing base via the tensioning jack, and a front fixing jack is provided on top of the wind-resistant rope fixing base, one end of the wind-resistant rope is connected to the wind-resistant rope fixing base via the front fixing jack.

[0007] Preferably, the suspension cable fixed foundation comprises a vertical rotating tower, a first bearing platform and a first pile foundation, the first bearing platform is fixed to the top of the first pile foundation, at least two first bearing platforms are provided and a vertical rotating tower is fixed thereon, the vertical rotating tower comprises a vertical pillar and a cross beam connection part, at least two vertical pillars are provided and connected to each one of the first bearing platforms, the vertical pillars are arranged along the width direction of the arch rib, and at least two cross beam connection parts are connected at intervals between adjacent vertical pillars.

[0008] Preferably, two sets of first and second tensioning jacks are symmetrically fixed on both sides of the top of the suspension cable fixing base, the suspension cable includes a first suspension cable and a second suspension cable, the two sets of first tensioning jacks are each connected to one end of the first suspension cable, and the other ends of the first suspension cable are each connected to the middle upper part of the arch ring on the same side as the corresponding arch rib segment, and the two sets of second tensioning jacks are each connected to one end of the second suspension cable, and the other ends of the second suspension cable are each connected to the middle lower part of the arch ring on the same side as the corresponding arch rib segment.

[0009] Preferably, a rear fixing device is further provided at the rear of the sling cable fixing base, the rear fixing device being connected to the top of the sling cable fixing base via an anchor rope, When constructing the suspension cable fixing base and the wind-resistant cable fixing base, the installation of the post-fixing device is completed first, and then an anchor rope is connected between the post-fixing device and the suspension cable fixing base to apply preload.

[0010] Preferably, the post-anchor device includes a second bearing platform and a second pile foundation, the second bearing platform is fixed to the top of the second pile foundation, there are at least two second bearing platforms, and a post-anchor jack is fixed to the top of each of them, the post-anchor jack is connected to one end of the anchor rope, and the other end of the anchor rope is connected to the top of the corresponding wind-resistant cable fixing base on the same side as the anchor rope.

[0011] Preferably, the wind-resistant cable fixed foundation includes a third bearing platform and a third pile foundation, and a third bearing platform is fixed to the top of the third pile foundation, and there are at least two third bearing platforms, and the third bearing platform is lower than the connection point of the suspension cable and the arch rib segment; The top of the third bearing platform is provided with front-anchoring jacks, which include two sets of first front-anchoring jacks and two sets of second front-anchoring jacks, and the wind-resistant cables include a first wind-resistant cable and a second wind-resistant cable. One set of the first front-anchoring jack and the second front-anchoring jack is fixed to the top of each of the third bearing platforms, and each of the two sets of first front-anchoring jacks is connected to one end of the first wind-resistant cable, with the other end of the first wind-resistant cable being connected to the middle upper part of the arch ring on the same side as the corresponding arch rib segment. The two sets of second front-anchoring jacks are each connected to one end of the second wind-resistant cable, with the other end of the second wind-resistant cable being connected to the middle lower part of the arch ring on the same side as the corresponding arch rib segment.

[0012] Preferably, during the process of joining and rotating the arch rib segments, a monitoring system is used to monitor the position and linearity of the arch rib, the monitoring system includes a 4D laser point cloud collection device and a suspension control system, the suspension control system is electrically connected to the 4D laser point cloud collection device, the suspension ropes and the wind resistance ropes, the 4D laser point cloud collection devices are attached to the front and rear of the arch rib segments and collect data including the position coordinates and linearity of the arch rib segments and transmit it to the suspension control system, and the suspension control system controls the length and rope tension of the suspension ropes and the wind resistance ropes, thereby controlling the installation position and suspension position of the arch rib segments within an error range.

[0013] Preferably, after the rotatable structure is attached, temporary fixing structures are attached to the front and rear of the lower end of the arch rib segment closest to the arch support so as to fix the arch rib segment closest to the arch support to the arch support; Before the lowering work is carried out, the temporary fixing structure is removed.

[0014] Preferably, before removing the temporary fixing structure, a relaxation device is attached to the underside and side of the arch rib, the relaxation device including a reverse push-out mechanism and a push-out mechanism, the reverse push-out mechanism including a rigid support structure, one end of which is supported on the outer surface of the position temporarily fixed to the bottom of the arch rib upper chord and the other end of which is fixed to the arch support, the push-out mechanism including an upper sealing plate, a lower sealing plate and a push-out jack set, the upper sealing plate is fixedly connected to the underside of the arch rib lower chord, the lower sealing plate is fixedly connected to the top surface of the temporary fixing structure that is temporarily fixed to the underside of the arch rib lower chord and has completed cutting and separation, and the push-out jack set is fixed between the upper sealing plate and the lower sealing plate, Before removing the temporary fixing structure, the rigid support structure is fixed to the outside of the arch rib upper chord, and the top of the rigid support structure is pressed tightly against the outer surface of the arch rib upper chord. Each time the connection between one arch rib lower chord and the temporary fixing structure is released, an upper sealing plate and a lower sealing plate are welded respectively to the bottom of the arch rib lower chord and the top of the temporary fixing structure that has been cut and separated. The extrusion jack set is raised to the appropriate height and used to support the arch rib lower chord. After all the arch rib lower chords are released from the temporary fixing structure and the extrusion mechanism is installed, the extrusion height of the extrusion jack set is adjusted to coordinate with the suspension ropes and wind-resistant ropes to control the gradual hanging of the arch rib. [Effects of the Invention]

[0015] The beneficial effects of the present invention are as follows: (1) In the present invention, the arch rib segments are joined vertically, so there is no need to erect shoring underwater, which avoids impacts on navigation and flood drainage. It also solves the problem of erection difficulties caused by the height of the pillars being too high in valley areas, and effectively shortens the construction period, thereby reducing the construction costs of erecting shoring. (2) The present invention employs a cable system that combines wind-resistant cables and suspension cables, and by preloading each cable in advance, it is possible to prevent the arch rib from being tilted upward due to the vertical wind load at the moment of suspension, thereby increasing the stability of the vertical joint. (3) The present invention further adopts a temporary fixing structure and a back fixing structure, which can further ensure the stability of the vertical joining process of the arch rib segments and the safety of the rotation process. [Brief explanation of the drawings]

[0016] [Figure 1] This is a schematic diagram of constructing a post-fixing device, a suspension cable fixing base, and a wind-resistant cable fixing base in the construction method of the present invention. [Figure 2] FIG. 10 is a schematic diagram showing a rotatable structure attached to the lower end of the arch rib segment closest to the arch support and connected to the arch support in the construction method of the present invention. [Figure 3] FIG. 10 is a schematic diagram showing the joining of one arch rib segment reaching a predetermined length in the construction method of the present invention. [Figure 4] FIG. 10 is a schematic view of the temporary fixing structure according to the construction method of the present invention after dismantling. [Figure 5] FIG. 10 is a schematic diagram showing the arch rib segment rotating until it reaches its designed position in the construction method of the present invention. [Figure 6] FIG. 10 is a schematic view of a temporary fixing structure according to an embodiment after a force relief device has been installed before the structure is removed. [Figure 7] FIG. 2 is a structural schematic diagram of a reverse extrusion mechanism. [Figure 8] FIG. 2 is a structural schematic diagram of a pushing mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0017] The present invention will be further described below based on specific examples, but the scope of protection of the present invention is not limited to the following examples.

[0018] Example 1 A vertical joining and lowering method for arch ribs, comprising the steps of: In the step of constructing the sling cable fixing base 200 and the wind-resistant cable fixing base 500, as shown in Figure 1, the construction of the sling cable fixing base 200 is completed in advance behind the arch support 300, and the construction of the wind-resistant cable fixing base 500 is completed in front of the arch support 300. There are no strict requirements regarding the construction order of the arch support 300, sling cable fixing base 200, and wind-resistant cable fixing base 500; they can be constructed simultaneously, alternately, or in a certain order, as long as they are completed before the next step begins.

[0019] In the step of joining the arch rib segments 700 and attaching the slings 1300 and wind-resistant cables 1400, as shown in FIG. 2, a rotatable structure 400 is attached to the lower end of the arch rib segment 700 closest to the arch support 300, and connected to the arch support 300. Of course, the arch support 300 may be provided with embedded members to join the arch rib segments 700. Next, the arch rib segments 700 on one side of the arch rib are joined vertically upward one after another until they reach a predetermined length. As shown in FIG. 3, because the arch rib segments 700 are installed vertically, there is no need to erect underwater supports. During the joining process, the arch rib segments 700 can be erected one by one using a large crane, and then welded to the previous arch rib segment 700 after erection. During or after the vertical joining is completed, a sling 1300 is attached to the rear of the arch rib segment 700 in the direction of rotation to provide a preload. The sling 1300 is adjustable in length, with one end connected to the sling 1300 fixing base 200 and the other end connected to the arch rib segment 700. A wind-resistant cable 1400 is attached to the front and below the direction of rotation of the arch rib segment 700 to provide a preload. The wind-resistant cable 1400 is adjustable in length, with one end connected to the wind-resistant cable fixing base 500 and the other end connected to the arch rib segment 700. The sling 1300 and the wind-resistant cable 1400 provide a preload, which prevents the arch rib segment 700 from tipping over due to a vertical wind load at the moment of hanging and increases the stability of the vertical joining.

[0020] In the step of constructing the lowering, the lengths of the suspension ropes 1300 and the wind-resistant ropes 1400 are adjusted so that the lower end of the arch rib segment 700 rotates downward around the rotatable structure 400 as the axis until the upper end reaches the designed position, i.e., as shown in Figure 5, once it has rotated to the designed position, the wind-resistant ropes 1400 are first removed.

[0021] Thereafter, the arch rib segments can be aligned by referring to the prior art. When the arch rib segment 700 on the other side is installed in place, the arch rib segment 700 on which the lowering work has been completed can be welded to the arch rib segment 700 on the other side, and then the connection between the arch rib segment 700 and the arch support 300 can be completed, or the connection between the arch rib segment 700 on which the lowering work has been completed and the arch support 300 can be completed, and then the alignment and connection between the arch rib segments 700 on both sides can be completed, and finally the sling 1300 can be removed.

[0022] Preferably, a tensioning jack 1000 is provided on top of the sling cable fixing base 200, one end of the sling cable 1300 is connected to the sling cable fixing base 200 via the tensioning jack 1000, a front fixing jack 1200 is provided on top of the wind-resistant cable fixing base 500, one end of the wind-resistant cable 1400 is connected to the wind-resistant cable fixing base 500 via the front fixing jack 1200. By providing the jacks, the lengths of the sling cable 1300 and the wind-resistant cable 1400 can be better adjusted.

[0023] Preferably, this embodiment provides a specific structure for the sling fixed foundation 200, which includes a vertical rotation tower 203, a first bearing platform 201, and a first pile foundation 202. The first bearing platform 201 is fixed to the top of the first pile foundation 202, and the vertical rotation tower 203 is fixed to the first bearing platform 201. The vertical rotation tower 203 includes a vertical column and a cross beam connector, with at least two vertical columns connected to each first bearing platform 201 and aligned along the width of the arch rib. At least two cross beam connectors are connected at intervals between the vertical columns. The first pile foundation 202 can be four reinforced concrete pile foundations located at the four corners of the bottom of the first bearing platform 201 and constructed using conventional methods. Embedded components are installed in the first bearing platform 201 and connected to the vertical rotation tower 203 to ensure the stability of the vertical rotation tower 203. The vertical columns can be made of steel pipes, with the positions of the two columns corresponding to the left and right arches of the arch rib segment, respectively, and the spacing between them being the same as or slightly smaller than the spacing between the left and right arches. The two columns are connected by a crossbeam connector, which forms the vertical rotation tower 203, and the crossbeam connector can be made of a truss structure.

[0024] Preferably, two sets of first tensioning jacks 1001 and second tensioning jacks 1002 are fixed symmetrically on both sides of the top of the suspension cable fixing base 200, and the suspension cable 1300 includes a first suspension cable 1301 and a second suspension cable 1302, and each of the two sets of first tensioning jacks 1001 is connected to one end of the first suspension cable 1301, and the other end of the first suspension cable 1301 is connected to the middle upper part of the arch ring on the same side as the corresponding arch rib segment 700, and each of the two sets of second tensioning jacks 1002 is connected to one end of the second suspension cable 1302, and the other end of the second suspension cable 1302 is connected to the middle lower part of the arch ring on the same side as the corresponding arch rib segment 700. In this embodiment, a sling-roof fixed base 200 including a vertical rotating tower 203 is used. A set of first tensioning jacks 1001 and a set of second tensioning jacks 1002 are fixed to the top of each column, symmetrically arranged about the vertical centerline of the vertical rotating tower 203. Each set of tensioning jacks 1000 may include one or more jacks and may be configured according to load requirements. The first tensioning jacks 1001 and second tensioning jacks 1002 can be secured by anchor boxes, which are welded or bolted to the vertical rotating tower 203 to enhance the strength of the tensioning jacks 1000. The first and second tensioning jacks 1301 and 1302 can also be connected to the arch ring by anchors. The slings 1300 are typically connected to the arch rib upper chord 1600 of the arch.

[0025] Preferably, a rear anchoring device 100 is further provided behind the sling cable fixing base 200, connected to the top of the sling cable fixing base 200 via an anchor rope 1500. The rear anchoring device 100 can better ensure the stability of the vertical rotating tower 203 during the tensioning process of the sling cable 1300. When installing the sling cable fixing base 200 and the wind-resistant cable fixing base 500, the installation of the rear anchoring device 100 is completed first, and then the anchor rope 1500 is connected between the rear anchoring device 100 and the sling cable fixing base 200 to apply preload. The installation sequence of the rear anchoring device 100, arch support 300, sling cable fixing base 200, and wind-resistant cable fixing base 500 is not strictly required and can be performed simultaneously, alternately, or on a first-come, first-served basis. However, the installation of the rear anchoring device 100 is generally completed before the installation of the vertical rotating tower 203 is completed to facilitate the installation of the anchor rope 1500.

[0026] Preferably, the post-anchoring device 100 includes a second bearing platform 101 and a second pile foundation 102, the second bearing platform 101 is fixed to the top of the second pile foundation 102, there are at least two second bearing platforms 101, each with a post-anchoring jack 1100 fixed to the top, the post-anchoring jack 1100 is connected to one end of an anchor rope 1500, the other end of the anchor rope 1500 is connected to the top of the wind-resistant cable fixed base 500 on the same side as the anchor rope. In this embodiment, the second pile foundation 102 uses two reinforced concrete pile foundations, and the second bearing platform 101 is equipped with embedded components, making it easy to connect to the post-anchoring jack 1100. The rear-anchoring jacks 1100 are generally installed in two sets symmetrically, each connected to the top of the upright on the same side. The rear-anchoring jacks 1100 can be fixed by an anchor box, and the other end of the anchor rope 1500 can also be connected to the wind-resistant rope fixing base part 500 by an anchor.

[0027] Preferably, the wind-resistant cable fixed foundation 500 includes a third bearing platform 501 and a third pile foundation 502, and the third bearing platform 501 is fixed to the top of the third pile foundation 502, and there are at least two third bearing platforms 501, which are lower than the connection points of the sling cables 1300 and the arch rib segments 700. In this embodiment, the arch rib segment 700 on the other side of the arch rib, i.e., the right-hand arch rib segment 700 in the direction shown in Figure 3, has been pre-installed in the arch rib holder 900, and although the right-hand arch rib segment 700 is basically constructed on land, the arch rib segment farthest from the right-hand arch support is located above the river, and in order to construct the arch rib holder 900 that supports this arch rib segment, it is necessary to install the third bearing platform 501 and the third pile foundation 502, and this embodiment utilizes this existing third bearing platform 501 and third pile foundation 502 as the wind-resistant cable fixed foundation 500. A front fixing jack 1200 is provided on the top of the third bearing platform 501, and the front fixing jack 1200 includes two sets of first front fixing jacks 1201 and two sets of second front fixing jacks 1202. The wind resistance rope 1400 includes a first wind resistance rope 1401 and a second wind resistance rope 1402. A set of first front fixing jacks 1201 and a second front fixing jack 1202 is fixed on the top of each third bearing platform 501, and two sets of first front fixing jacks 1201 and 1202 are fixed on the top of each third bearing platform 501. The anchoring jacks 1201 are each connected to one end of a first wind rope 1401, the other ends of which are connected to the upper middle part of the arch ring on the same side as the anchoring jack in the corresponding arch rib segment 700, and the two sets of second front anchoring jacks are each connected to one end of a front two wind rope 1402, the other ends of which are connected to the lower middle part of the arch ring on the same side as the anchoring jack in the corresponding arch rib segment 700. The wind ropes 1400 are generally connected to the arch rib lower chord 1800 of the arch ring.

[0028] Preferably, the rotatable structure 400 includes an upper rotating hinge 402, a lower rotating hinge 401, and a rotating shaft 403, the upper part of the upper rotating hinge 402 is connected to the lower end of the arch rib segment 700, and the lower part of the lower rotating hinge 401 is connected to the arch support 300, and the upper rotating hinge 402 and the lower rotating hinge 401 are rotatably connected via the rotating shaft 403. In this embodiment, two sets of rotatable structures 400 are provided, corresponding respectively to the front and rear surfaces of the middle of the lower end of the arch rib segment 700 in the direction shown in FIG. 2, i.e., the middle of the lower ends of the left and right arches.

[0029] Preferably, during the process of joining and rotating the arch rib segments, a monitoring system is used to monitor the position and shape of the arch rib, which monitoring system includes a 4D laser point cloud collector and a suspension control system, which is electrically connected to the 4D laser point cloud collector, the suspension ropes, and the wind resistance ropes, which are attached to the front and rear of the arch rib segments to collect data including the position coordinates and shape of the arch rib segments and transmit it to the suspension control system, which controls the length and rope tension of the suspension ropes and wind resistance ropes to control the installation position and suspension position of the arch rib segments within an error range. During the process of assembling the arch rib segments 700, the 4D laser point cloud collector can be used to determine the lifting position of the arch rib segments 700 and assist in adjusting the lifting position. During the lowering construction process, based on feedback from the 4D laser point cloud collection device, the suspension control system controls the tensioning jack 1000 and the front-anchoring jack 1200 to control the tension of the suspension ropes 1300 and the wind-resistant ropes 1400, thereby adjusting the position of the arch rib segment 700. Of course, to stabilize the vertical rotating tower, the rear-anchoring jack 1100 is also connected to the suspension control system, and the tension of the anchor ropes 1500 can also be controlled through the suspension control system. 4D laser point cloud collection devices can be installed on both banks of the river, and the images are collected by the 4D laser point cloud collection device. After collection, coordinate system transformation is required to obtain the position coordinates of the arch rib segment 700, which can be achieved using conventional technology.

[0030] Preferably, after the rotatable structure 400 is installed, temporary fixing structures 600 are attached to the front and rear of the lower end of the arch rib segment 700 closest to the arch support 300, so as to fix the arch rib segment 700 closest to the arch support 300 to the arch support. That is, in the direction shown in FIG. 2, the left and right sides of the bottom end of the arch rib segment 700 are generally fixed to the arch support 300 by welded steel pipes. Of course, the arch support 300 is provided with corresponding embedding members to connect the steel pipes. The temporary fixing structures 600 include a rear temporary fixing structure 601 and a front temporary fixing structure 602, with the rear temporary fixing structure 601 connected to the arch rib upper chord 1600 and the front temporary fixing structure 602 connected to the arch rib lower chord 1800. Before lowering construction, the temporary fixing structures are removed, as shown in FIG. 4. This embodiment not only lists one temporary fixing structure 600 that is easy to install, but also other temporary fixing structures 600 that only require fixing the arch rib segments 700 may be adopted.

[0031] Furthermore, the time node for installing the slings 1300 and wind-resistant cables 1400 is preferably completed after the installation of the arch rib segments 700 to which the slings 1300 and wind-resistant cables 1400 are correspondingly connected, i.e., the connection between the slings 1300, arch rib segments 700, and sling-rope-fixing base 200 and the connection between the wind-resistant cables 1400, arch rib segments 700, and wind-resistant cable-fixing base 500 are correspondingly performed, thereby better ensuring stability during the installation process of the arch rib segments 700, reducing installation risks and minimizing misalignment of the arch rib segments 700 due to air currents. Preferably, when vertically joining the arch rib segments 700, the back cage 800 is installed at the same time to facilitate welding between the arch rib segments 700. The back cage 800 has stairs to facilitate workers' climbing and descending, and is surrounded by fences to prevent workers from falling. The back cage 800 is also assembled in segments, matching the assembled height of the arch rib segment 700. After each back cage 800 is constructed, a welding work platform is installed on the top side, surrounding the outer periphery of the arch rib segment 700, and the next arch rib segment can be welded on this welding work platform. After welding of the next arch rib segment is completed, another back cage 800 segment is constructed, and the welding work platform is installed. The above operation is repeated until the arch rib segment 700 reaches the designed height. Before lowering construction, the back cage 800 and welding work platform are removed.

[0032] Based on the above preferred technical solution, combined with the geographical environment of the construction application of this embodiment, the specific steps of this embodiment include: In the step of installing the sling cable fixing base 200, wind-resistant cable fixing base 500, and rear anchoring device 100, as shown in Figure 1, the installation of the sling cable fixing base 200 and rear anchoring device 100 is completed in advance behind the arch support 300, and the installation of the wind-resistant cable fixing base 500 is completed in front of the arch support 300. In this embodiment, the wind-resistant cable fixing base 500 directly utilizes the third bearing platform 501 located in the other arch rib segment 700 and below the arch rib holder 900 closest to the sling cable fixing base 200, thereby saving installation costs. There are no strict requirements regarding the installation order of the arch support 300, sling cable fixing base 200, wind-resistant cable fixing base 500, and rear anchoring device 100; they can be installed simultaneously, alternately, or in a certain order, as long as they are completed before the next step begins. A tensioning jack 1000, a front fixing jack 1200, and a rear fixing jack 1100 are attached to the top of the suspension rope fixing base 200, the wind-resistant rope fixing base 500, and the rear fixing device 100, respectively, and an anchor rope 1500 is connected between the rear fixing jack 1100 and the top of the suspension rope fixing base 200 to apply preload.

[0033] In the step of joining the arch rib segments 700 and attaching the slings 1300 and wind-resistant cables 1400, as shown in FIG. 2, a rotatable structure 400 is attached to the lower end of the arch rib segment 700 closest to the arch support 300 and connected to the arch support 300, an embedded member is provided on the arch support 300 and connected to the lower rotating hinge, and an upper rotating hinge 402 is welded to the lower end of the arch rib segment 700 closest to the arch support 300 and connected to the lower rotating hinge 401 via a rotating shaft 403, and a temporary fixing structure 600 is welded to the lower end of the arch rib segment 700 closest to the arch support 300, and the lower end of the temporary fixing structure 600 is also connected to the embedded member previously embedded in the arch support 300 to fix the arch rib segment 700 closest to the arch support 300. A large crane is then used to sequentially join the arch rib segments 700 on one side of the arch rib vertically upward, and adjacent arch rib segments 700 are welded together until the designed length, i.e., the state shown in Figure 3, is reached. During or after the vertical joining is completed, a sling 1300 is attached to the rear of the arch rib segment 700 in the direction of rotation to provide preload. The sling 1300 has an adjustable length and one end is connected to the tensioning jack 1000 and the other end is connected to the arch rib segment 700. A wind-resistant cable 1400 is attached to the front and below the direction of rotation of the arch rib segment 700 to provide preload. The wind-resistant cable 1400 has one end connected to the front-anchoring jack 1200 and the other end connected to the arch rib segment 700.

[0034] In the lowering step, as shown in Figure 4, the tensioning jack 1000 and the front anchoring jack 1200 are used in coordination to adjust the lengths of the slings 1300 and the wind-resistant cables 1400, and the lower end of the arch rib segment 700 is rotated downward around the rotatable structure 400 to the designed position, i.e., as shown in Figure 5. Once the upper end reaches the designed position, the wind-resistant cables 1400 are first removed. The arch rib segments can then be aligned by reference to the prior art. In this embodiment, when the other arch rib segment 700 is welded, the arch rib segment 700 where the rotating body is located must be welded to the other arch rib segment 700, and then the arch rib segment 700 and the arch support 300 can be connected. Alternatively, the arch rib segment 700 that has been lowered can be connected to the arch support 300, and then the alignment and connection between the two arch rib segments 700 can be completed, and the slings 1300 can be finally removed.

[0035] Example 2 At the moment when the arch rib rotates vertically and releases the connection support between the temporary fixing structure and the arch rib downward, a relatively large instantaneous force is generated, causing the sling rope 1300 and the vertical rotation tower 203 to be suddenly subjected to force, which in turn makes it impossible to control the rope force of the suspension control system, and the arch rib may become momentarily unstable. In order to solve the above-mentioned problem, as shown in Figure 6, this embodiment adds a force release device to the first embodiment. Before the temporary fixing structure is removed, force release devices are attached to the underside and sides of the arch rib, specifically: The relaxation device includes a reverse extrusion mechanism 1700 and an extrusion mechanism 1900. As shown in FIG. 7, the reverse extrusion mechanism 1700 includes a rigid support structure, one end of which is supported on the outer surface (here, the outer surface refers to another side away from the arch rib lower chord 1800) of the arch rib upper chord 1600 at a position where the rigid support structure is temporarily fixed to the bottom of the arch rib upper chord 1600, and the other end of which is fixed to the arch support. The reverse extrusion mechanism 1700 utilizes the reaction force of the arch support 3 to form a rigid support for the arch rib upper chord 1600, thereby preventing the arch rib upper chord 1600 from tilting backward. As shown in Figure 8, the extrusion mechanism 1900 includes an upper sealing plate 1901, a lower sealing plate 1903, and an extrusion jack set 1902, wherein the upper sealing plate 1901 is used to make a fixed connection to the bottom surface of the arch rib lower chord 1800, and the lower sealing plate 1903 is temporarily fixed to the underside of the arch rib lower chord 1800 and is used to make a fixed connection to the top surface of the temporary fixed structure after cutting and separation is completed, and the extrusion jack set 1902 is fixed between the upper sealing plate 1901 and the lower sealing plate 1903. In addition, when disconnecting the arch rib lower chord 1800 from the temporary fixing structure, the temporary fixing structure is generally cut to a certain length, maintaining a certain distance between the arch rib lower chord 1800 and the temporary fixing structure; when disconnecting the first arch rib lower chord 1800 from the temporary fixing structure, the position of the arch rib is kept constant by the connection between the other arch rib lower chords 1800 and the temporary fixing structure, ensuring the safety of the installation of the push-out mechanism 1900; when disconnecting the last arch rib lower chord 1800 from the temporary fixing structure, it is supported by the temporary fixing structure and the push-out mechanism 1900 to ensure the safety of the installation of the last push-out mechanism 1900 of the other arch rib lower chords 1800.

[0036] Before releasing the temporary fixing structure, the rigid support structure is fixed to the outside of the arch rib upper chord 1600, and its top is brought into close contact with the outer surface of the arch rib upper chord 1600, and then the rear temporary fixing structure 601 connected to the arch rib upper chord 1600 is released. Next, the arch rib lower chord 1800 is disconnected from the front temporary fixing structure 602, and each arch rib lower chord 1800 is disconnected from the rear temporary fixing structure 601. Then, an upper sealing plate 1901 and a lower sealing plate 1903 are welded to the underside of the arch rib lower chord 1800 and the upper surface of the temporary fixing structure that has been cut and separated. The extrusion jack set 1902 is then positioned and raised to an appropriate height to support the arch rib lower chord 1800. After all the arch rib lower chords 1800 are disconnected from the front temporary fixing structure 602 and the installation of the extrusion device is completed, the temporary fixing structure is completely disconnected from the arch rib segment 700, and the extrusion height of the extrusion jack set 1902 is adjusted, which works in conjunction with the slings and wind-resistant cables 1400 to control the slow hanging of the arch rib.

[0037] The relaxation device in this embodiment is further optimized. This embodiment provides a specific structure for the rigid support structure, which includes a wedge-shaped mat. The wedge-shaped mat's shape better fits the arch support 3 and the arch rib upper chord 1600, providing support for the arch rib upper chord 1600. The wedge-shaped mat includes a plurality of spaced-apart rigid support plates 1702 arranged along the width of the arch rib to support the arch rib upper chord 1600 of a certain width. One end of each rigid support plate 1702 is aligned with and supported by the outer surface of the temporarily anchored lower end of the arch rib upper chord 1600, and the other end is fixed to the arch support 3. The number of wedge-shaped mats generally corresponds to the number of arch rib upper chords 1600, i.e., one wedge-shaped mat is supported for each arch rib upper chord 1600. More preferably, to ensure the supporting force of the arch rib upper chord 1600, the rigid support plate 1702 is made of a steel plate, and preferably has a thickness of 20 mm or more.

[0038] To install the rigid support plate 1702, it is preferable to install an embedded steel plate 1701, which is embedded in the arch support 3 when the arch support 3 is poured, with its top exposed from the arch support 3 and connected to the other end of the rigid support plate 1702. The connection method is generally welding, which is convenient and fast.

[0039] The reverse extrusion mechanism also includes reinforcing steel 1703, which is fixed to the bottom of the arch rib upper chord 1600 or to the top of the corresponding temporary fixing structure after the connection between the arch rib upper chord 1600 and the temporary fixing structure is released. The temporary fixing structure here refers to a temporary fixing structure connected to the bottom of the arch rib upper chord 1600, and generally one reinforcing steel 1703 is provided for each arch rib upper chord 1600. The connection is generally released by cutting, and after cutting, a certain space is left between the arch rib upper chord 1600 and the temporary fixing structure, and the reinforcing steel 1703 is welded to increase the contact area, allowing the temporary fixing structure to support the arch rib upper chord 1600. After the installation of the other components of the release device is completed, by removing the reinforcing steel 1703 before lowering the arch rib, the arch rib upper chord 1600 can be rotated without being affected by the reinforcing steel 1703.

[0040] Preferably, at least two push-out mechanisms 1900 are provided to match the number of arch rib lower chords 1800, i.e., one push-out mechanism 1900 is attached to each arch rib lower chord 1800. If there are four arch rib lower chords 1800, four lift mechanisms 1900 are attached.

[0041] Preferably, as shown in FIG. 2, in the push-out mechanism 1900, the push-out jack set 1902 includes at least two jacks, which are arranged to tilt backward to release the arch rib lower chord 1800, in order to achieve the purpose of supporting the arch rib lower chord 1800 in a more balanced manner and releasing the arch rib lower chord 1800 gradually.

[0042] Preferably, the extrusion mechanism 1900 also includes a remote control system, which is electrically connected to the extrusion jack set 1902, so that the extrusion and lowering of the jacks can be easily controlled through the remote control system, thereby ensuring the safety of construction.

[0043] Since the pushing mechanism 1900 requires a large load, it is preferable that the thickness of the upper sealing plate 1901 and the lower sealing plate 1903 is 25 mm or more, and in this embodiment, steel plates with a thickness of 30 mm are used.

[0044] Compared to the above more preferred embodiment, this embodiment provides a more specific operating method, in which embedded steel plates 1701 are installed before the arch supports 3 are cast, and before the temporary fixing structures 600 are released, a rigid support structure is welded to the embedded steel plates 1701 and its top is tightly attached to the outer surface of the arch rib upper chords 1600. Each arch rib upper chord 1600 is equipped with a reverse extrusion mechanism 1700, which applies a reaction force to the arch rib and prevents the arch rib from reversing the moment the temporary fixing structures are released. Furthermore, after the connection between the rear-mounted temporary fixing structures 601 and the arch rib upper chords 1600 is released, a sheet metal 1703 is welded to the bottom of the arch rib upper chords 1600 or to the top of the corresponding rear-mounted temporary fixing structures 601. After the installation of the reversing mechanism 1700 is completed, the extrusion mechanism 1900 is installed. Each time the connection between one arch rib lower chord 1800 and the front temporary fixing structure 602 is released, the upper sealing plate 1901 and the lower sealing plate 1903 are welded to the underside of the arch rib lower chord 1800 and the top surface of the front temporary fixing structure 602 that has been cut and separated, respectively. The extrusion jack set 1902 is then placed and raised to a corresponding height, and the arch rib is then pushed up by the extrusion jack set 1902. The arch rib lower chords 1800 are supported, and the connections between all of the arch rib lower chords 1800 and the temporary fixing structure are released, and the extrusion mechanism is installed. At this time, the connections between the temporary fixing structure and the arch rib segments 700 are completely released, the reinforcing steel 1703 is removed, and the lifting jack set 1902, which simultaneously removes the four chords, is remotely controlled and lowered in height in cooperation with the slings 1300 and wind-resistant ropes 1400, thereby achieving the purpose of slowly releasing the arch rib.

[0045] In this embodiment, the reverse extrusion mechanism 1700 is used to prevent the arch rib from falling backward, and the extrusion mechanism 1900 is used to maintain the balance of the arch rib, and these mechanisms cooperate to achieve a gradual hanging of the arch rib, thereby reducing the probability of the arch rib becoming momentarily unstable when the connection support between the temporary fixing structure and the arch rib is released. [Explanation of symbols]

[0046] 100, rear anchorage device; 101, second bearing platform; 102, second pile foundation; 200, suspension cable fixed base; 201, first bearing platform; 202, first pile foundation; 203, vertical rotation tower; 300, arch support; 400, rotatable structure; 401, lower rotation hinge; 402, upper rotation hinge; 403, rotation axis; 500, wind cable fixed base; 501, third bearing platform; 502, third pile foundation; 600, temporary fixed structure; 601, rear temporary fixed structure; 602, front temporary fixed structure; 700, arch rib segment; 800, back cage; 900, arch rib holder; 1000, tension jack; 10 01, first tensioning jack; 1002, second tensioning jack; 1100, rear fixing jack; 1200, front fixing jack; 1201, first front fixing jack; 1202, second front fixing jack; 1300, sling; 1301, first sling; 1302, second sling; 1400, wind resistance rope; 1401, first wind resistance rope; 140 2. Second wind-resistant rope; 1500, anchor rope; 1600, arch rib upper chord; 1700, reverse extrusion mechanism; 1701, embedded steel plate; 1702, rigid support plate; 1703, reinforcing steel; 1800, arch rib lower chord; 1900, extrusion mechanism; 1901, upper sealing plate; 1902, extrusion jack set; 1903, lower sealing plate.

Claims

1. A vertical joining and lowering method for arch ribs, A step of constructing a suspension cable fixing base and a wind-resistant cable fixing base, in which the construction of the suspension cable fixing base is completed in advance behind the arch support and the construction of the wind-resistant cable fixing base is completed in front of the arch support; a step of joining the arch rib segments and attaching the slings and wind-resistant cables, in which a rotatable structure is attached to the lower end of the arch rib segment closest to the arch support and connected to the arch support, and then the arch rib segments on one side of the arch rib are joined vertically upward one after another until they reach a predetermined length, and during or after the vertical joining is completed, a sling cable is attached to the rear of the arch rib segment in the rotational direction to apply preload, the sling cable having an adjustable length, one end connected to the sling cable fixed base and the other end connected to the arch rib segment, and a wind-resistant cable is attached to the front and below the rotational direction of the arch rib segment to apply preload, the length of the wind-resistant cable being adjustable, one end connected to the wind-resistant cable fixed base and the other end connected to the arch rib segment; and a lowering step of adjusting the lengths of the suspension ropes and wind-resistant ropes so that the lower ends of the arch rib segments rotate downward around the rotatable structure until the upper ends reach the designed position.

2. A vertical joining and lowering method for arch ribs as described in claim 1, characterized in that a tensioning jack is provided on the top of the suspension cable fixing base, one end of the suspension cable is connected to the suspension cable fixing base via the tensioning jack, a front fixing jack is provided on top of the wind-resistant cable fixing base, and one end of the wind-resistant cable is connected to the wind-resistant cable fixing base via the front fixing jack.

3. 2. The method for vertically joining and lowering an arch rib according to claim 1, wherein the suspension cable fixed foundation comprises a vertical rotation tower, a first bearing platform and a first pile foundation, the first bearing platform is fixed to the top of the first pile foundation, at least two first bearing platforms are provided and a vertical rotation tower is fixed thereon, the vertical rotation tower comprises a vertical pillar and a cross beam connecting part, at least two vertical pillars are provided and connected to each one of the first bearing platforms, the vertical pillars are arranged along the width direction of the arch rib, and at least two cross beam connecting parts are connected at intervals between adjacent vertical pillars.

4. The vertical joining and lowering method for arch ribs according to any one of claims 1 to 3, characterized in that two sets of first tensioning jacks and second tensioning jacks are symmetrically fixed to both sides of the top of the suspension cable fixing base, the suspension cable includes a first suspension cable and a second suspension cable, the two sets of first tensioning jacks are each connected to one end of the first suspension cable, and the other end of the first suspension cable is connected to the middle upper part of the arch ring on the same side as the first suspension cable in the corresponding arch rib segment, and the two sets of second tensioning jacks are each connected to one end of the second suspension cable, and the other end of the second suspension cable is connected to the middle lower part of the arch ring on the same side as the second suspension cable in the corresponding arch rib segment.

5. A rear fixing device is further provided behind the sling rope fixing base and connected to the top of the sling rope fixing base via an anchor rope, A vertical joining and lowering method for arch ribs as described in any one of claims 1 to 3, characterized in that when constructing the suspension cable fixing base and the wind-resistant cable fixing base, the construction of the post-fixing device is completed first, and then an anchor rope is connected between the post-fixing device and the suspension cable fixing base to apply pre-load.

6. The method for vertically joining and lowering an arch rib as described in claim 5, characterized in that the post-anchor device includes a second bearing platform and a second pile foundation, the second bearing platform is fixed to the top of the second pile foundation, there are at least two second bearing platforms, and a post-anchor jack is fixed to the top of each of them, the post-anchor jack is connected to one end of the anchor rope, and the other end of the anchor rope is connected to the top of the corresponding wind-resistant cable fixing foundation on the same side as the anchor rope.

7. The wind-resistant cable fixed foundation includes a third bearing platform and a third pile foundation, and a third bearing platform is fixed to the top of the third pile foundation, and there are at least two third bearing platforms, and the third bearing platforms are lower than the connection points of the suspension cable and the arch rib segment; 5. The method for vertically joining and lowering an arch rib according to claim 4, wherein front fixing jacks are provided on the top of the third bearing platform, the front fixing jacks including two sets of first front fixing jacks and two sets of second front fixing jacks, the wind resistance ropes including first wind resistance ropes and second wind resistance ropes, one set of the first front fixing jacks and second front fixing jacks are fixed to the top of each of the third bearing platforms, each set of the first front fixing jacks is connected to one end of the first wind resistance rope and the other end of the first wind resistance rope is connected to the middle upper part of the arch ring on the same side as the first wind resistance rope in the corresponding arch rib segment, and each set of the second front fixing jacks is connected to one end of the second wind resistance rope and the other end of the second wind resistance rope is connected to the middle lower part of the arch ring on the same side as the second wind resistance rope in the corresponding arch rib segment.

8. 2. The method for vertically joining and lowering an arch rib as claimed in claim 1, wherein a monitoring system is used to monitor the position and shape of the arch rib during the process of joining and rotating the arch rib segments, the monitoring system comprising a 4D laser point cloud collection device and a suspension control system, the suspension control system being electrically connected to the 4D laser point cloud collection device, the suspension ropes and the wind resistance ropes, the 4D laser point cloud collection devices being attached to the front and rear of the arch rib segments, collecting data including the position coordinates and shape of the arch rib segments and transmitting it to the suspension control system, and the suspension control system controlling the lengths and rope tensions of the suspension ropes and the wind resistance ropes to control the mounting positions and suspension positions of the arch rib segments within an error range.

9. after the rotatable structure is attached, temporary fixing structures are attached to the front and rear of the lower end of the arch rib segment closest to the arch support so as to fix the arch rib segment closest to the arch support to the arch support; 2. The method for vertically joining and lowering an arch rib according to claim 1, wherein the temporary fixing structure is removed before the lowering construction is carried out.

10. Before removing the temporary fixing structure, a relaxation device is attached to the underside and side of the arch rib, the relaxation device including a reverse push-out mechanism and a push-out mechanism, the reverse push-out mechanism including a rigid support structure, one end of which is supported on the outer surface of the position temporarily fixed to the bottom of the arch rib upper chord and the other end of which is fixed to the arch support, the push-out mechanism including an upper sealing plate, a lower sealing plate and a push-out jack set, the upper sealing plate is fixedly connected to the underside of the arch rib lower chord, the lower sealing plate is fixedly connected to the top surface of the temporary fixing structure that is temporarily fixed to the underside of the arch rib lower chord and has been cut and separated, and the push-out jack set is fixed between the upper sealing plate and the lower sealing plate, 10. The method for vertically connecting and lowering an arch rib as claimed in claim 9, wherein before removing the temporary fixing structure, the rigid support structure is fixed to the outside of the arch rib upper chord, and the top of the rigid support structure is tightly attached to the outer surface of the arch rib upper chord. Each time the connection between one arch rib lower chord and the temporary fixing structure is released, an upper sealing plate and a lower sealing plate are welded respectively to the bottom of the arch rib lower chord and the top of the temporary fixing structure that has been cut and separated. The extrusion jack set is raised to an appropriate height and used to support the arch rib lower chord. After all the arch rib lower chords are released from the temporary fixing structure and the extrusion mechanism is installed, the extrusion height of the extrusion jack set is adjusted to coordinate with the suspension ropes and wind-resistant ropes to control the slow hanging of the arch rib.

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