Large-span steel truss girder arch rib cantilever mounting and lifting equipment and construction method thereof

Abstract

The invention relates to the technical field of bridge construction, in particular to large-span steel truss girder arch rib cantilever installing and lifting equipment and a construction method thereof.The large-span steel truss girder arch rib cantilever installing and lifting equipment comprises lattice type stand columns, cantilever beams, back cables, lifting jacks and lifting cables, and the lattice type stand columns are composed of steel pipes and connecting systems, supported on arch springing arch ribs and connected with the arch springing arch ribs through wedge-shaped bases; the large-span steel truss girder arch rib cantilever installation lifting equipment comprises a cantilever beam, a lifting jack and a lifting box, the cantilever beam is welded to a lattice type stand column, the rear end of the cantilever beam is reversely pulled to a steel truss girder through an installed back cable, the lifting jack is installed on the cantilever beam, and one end of a lifting cable penetrates through the lifting jack. The high-altitude operation of the assembly of the arch ribs is changed into the low-altitude operation, the cantilever lifting mechanism on the arch is light and convenient, the adjustment of the arch rib closure is more intelligent and rapid, the construction risk is greatly reduced, the construction difficulty is reduced, the construction cost is saved, and the engineering construction safety is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, in particular to a large-span steel truss arch rib cantilever installation hoisting device and a construction method thereof. Background Art

[0002] At present, there are three main methods for installing arch ribs in large-span steel truss flexible arch bridges. The first is to set up an arch rib in-situ assembly bracket on the erected steel truss to assemble the arch ribs. The second is to set up a floor-standing lifting bracket, the bottom of the bracket is anchored by a pile foundation, and a through-hole jack is set on the top of the bracket to lift the arch ribs. The third is to set up a lifting bracket on the erected steel truss to lift the arch ribs. The first method requires the erection of high supports for the entire bridge according to the arch rib height, which requires a large amount of supports and poses a high risk of high-altitude operations; the second method requires a higher support height, and the pile foundation and ground-mounted steel pipe columns will have higher requirements on geological conditions and a longer construction period; the third method requires higher stiffness of the steel beams, and the handling of detailed load-bearing nodes is more difficult. All three methods require the erection of higher supports, which is uneconomical and difficult to construct.

[0003] Aiming at the limitations of the current existing technology, a large-span steel truss arch rib cantilever installation lifting equipment and a construction method thereof are proposed. Summary of the invention

[0004] The object of the present invention is to provide a large-span steel truss arch rib cantilever installation lifting device and a construction method thereof to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions: a large-span steel truss arch rib cantilever installation lifting equipment, comprising a lattice column, a cantilever beam, a back cable, a lifting jack and a lifting cable, wherein the lattice column is composed of a steel pipe and a connection system, supported on an arch foot arch rib, and connected to the arch foot arch rib through a wedge-shaped base, the cantilever beam is welded on the lattice column, and the rear end of the cantilever beam is pulled back on the steel truss beam through the installed back cable, the lifting jack is installed on the cantilever beam, and one end of the lifting cable passes through the lifting jack, and also includes: A lifting box, wherein the bottom of the lifting rope is fixedly connected to the lifting box; A guide mechanism, which is installed on a side of the lifting box close to the lattice column, and is used to guide and limit the lifting box when it is lifted; The lifting box is connected to two vertical lifting lugs at the middle long span arch rib through two connecting ropes at the bottom, and when the middle long span arch rib is lifted, the lifting jack above one end is operated first, and then the lifting jack above the other end is operated to prevent the middle long span arch rib from tilting due to unstable center of gravity when lifting; A lifting and positioning mechanism is installed at both ends of the lifting box, and after the middle long span arch rib is lifted and kept in a horizontal state, the middle long span arch rib is auxiliary positioned.

[0006] Wherein, the guide mechanism comprises two U-shaped guide frames installed on one side of the lifting box, and the two guide frames are respectively slidably sleeved on the outside of the lattice column; Grooves are provided on both sides of the guide frame, and positioning plates are slidably connected to the grooves. A bidirectional threaded rod is rotatably connected to the guide frame, and two positioning plates are threadedly sleeved on the outside of the bidirectional threaded rod. A synchronization rod is installed at one end of the two bidirectional threaded rods located inside the lifting box. The lifting box is provided with a synchronization assembly for synchronously driving the two synchronization rods, and through the provided guide mechanism, the middle long span arch rib is limited and guided during lifting.

[0007] Wherein, the synchronization assembly includes a rotating rod rotatably connected to the inside of the lifting box, and a rotating member for driving the rotating rod is installed at the lifting box; The two ends of the rotating rod are respectively fixedly connected with driving bevel gears, and the outer side of the driving bevel gear is meshedly connected with a rotating bevel gear. The two rotating bevel gears are respectively fixedly installed on one end of the two synchronous rods, and the two synchronous rods are driven synchronously through the synchronous assembly.

[0008] Among them, the rotating part includes a rotating motor installed at the lifting box, and a first rotating gear is fixedly installed at the output end of the rotating motor. A second rotating gear is meshed and connected to the outer side of the first rotating gear, and the second rotating gear is fixedly sleeved on the outer side of the rotating rod. Through the rotating part provided, the rotating rod is driven.

[0009] Wherein, the lifting and positioning mechanism comprises two side plates fixedly mounted on both sides of the lifting box, the side plates are provided with through holes, and positioning pieces are arranged through the through holes; A detection sleeve is provided on the inner side of the side plate, and one end of the detection sleeve is fixedly mounted on the outer side of the middle long span arch rib; The detection sleeve is provided with a detection member inside, and the detection sleeve detects its relative position through the detection member, and the lifting and positioning mechanism is provided to achieve the function of positioning one end of the middle long span arch rib.

[0010] Wherein, the positioning member comprises a hydraulic cylinder fixedly mounted on the lifting box, a push plate is fixedly mounted on the output end of the hydraulic cylinder, the push plate is located on the outside of the side plate, and a positioning sleeve is fixedly mounted on the inside of the push plate, and the positioning sleeve is arranged in an internal opening type; The positioning sleeve slides through the through hole, and a positioning groove is provided at one end of the positioning sleeve close to its internal opening, an electromagnetic coil is installed at the positioning groove, and a positioning piece is provided to achieve the function of positioning one end of the middle long span arch rib.

[0011] The detection member includes a connecting spring with one end fixedly connected to the detection sleeve, one end of the connecting spring is fixedly connected to a connecting plate, the connecting plate is slidably connected inside the detection sleeve, and a detection block is fixedly installed on a side of the connecting plate away from the connecting spring, a moving opening is provided on a side of the detection sleeve close to the side plate, and the detection block slides through the moving opening; A pressure sensor is arranged inside the detection sleeve and near the moving port, and the relative position of one end of the middle long span arch rib is detected through the detection piece.

[0012] Wherein, the detection block is in a spherical shape and is made of metal iron, so that the detection block can be used in conjunction with the detection sleeve.

[0013] A construction method for cantilever installation of a large-span steel truss arch rib using a lifting device for cantilever installation of a large-span steel truss arch rib, comprising the following steps: Step 1: construct bridge piers and temporary piers, and erect steel trusses using a beam erection crane; Step 2: Set up an arch rib assembly bracket on the erected steel truss. The arch rib assembly bracket is divided into three parts, namely two arch foot arch rib assembly brackets and a middle long span arch rib assembly bracket. The assembly bracket is reliably connected to the steel truss. The assembly brackets are grouped and connected by longitudinal and transverse connection systems to ensure the overall stability of the assembly bracket. For the arch foot arch rib assembly bracket, a group of brackets close to the fracture is stronger than the standard assembly bracket. This bracket will be used as the arch support bracket of the lifting mechanism in the later stage; Step 3: Install a wedge-shaped pad connected to the arch foot and arch rib on the top of the rear steel pipe column on the top of the arch support bracket, install a distribution beam on the top of the front steel pipe column, install rigid pads on both ends of the distribution beam corresponding to the web of the arch foot and arch rib, install a hydraulic adjustment jack in the middle, set a wedge-shaped pad on the top of the hydraulic adjustment jack to support the arch foot and arch rib, and weld a reinforcement partition within the pressure range of the lifting bracket inside the arch foot and arch rib to ensure that the local force of the arch foot and arch rib meets the requirements during lifting; Step 4: hoist the arch foot arch rib and the middle long span arch rib in blocks on the assembly bracket. The arch foot arch rib and the middle long span arch rib are composed of small segment arch ribs. The root of the first small segment arch rib of the arch foot arch rib is fixed to the steel truss node, and the other end is supported on the assembly bracket. The subsequent small segment arch ribs are also supported by the assembly bracket and connected with the previous small segment arch rib according to the designed linearity to form the arch foot arch rib and the middle long span arch rib; Step 5: Horizontal cable anchor boxes are provided on the sides of both ends of the middle long span arch rib. The horizontal cable is passed through the anchor box. One end of the middle long span arch rib is the anchoring end. The horizontal cable is anchored by a special anchor. The other end of the middle long span arch rib is the tensioning end. The horizontal cable is tensioned by a hydraulic jack. The horizontal cable in the assembled state of the arch rib is tightened. The installation position of the horizontal cable anchor box corresponds to the vertical lifting position. A vertical lifting lug is provided at the top plate of the middle long span arch rib to connect with the connecting cable. Step 6: Install the cantilever lifting mechanism at the front end of the arch foot and arch rib, pass one end of the lifting cable through the lifting jack, use the anchor of the lifting jack to clamp the lifting cable, connect the other end of the lifting cable to the lifting box, let the lifting cable and the lifting box droop naturally, and connect the lifting box to the middle long span arch rib through the connecting cable; Step 7: After the arch foot, arch rib and cantilever lifting mechanism are installed and checked, the horizontal cables on the middle long span arch rib are tensioned in stages, and the coordinates of the closure are measured. The horizontal coordinates of the arch rib port meet the closure conditions. Then, the lifting jacks and lifting cables on the cantilever lifting mechanism are used to lift the middle long span arch rib. When lifting the middle long span arch rib, the lifting jack above one end is operated first, and then the lifting jack above the other end is operated to prevent the middle long span arch rib from tilting due to unstable center of gravity when lifting. During the lifting process, the two lifting jacks cooperate with each other to lift, and under the action of the detection parts, the middle long span arch rib is lifted upward to keep the horizontal position. After lifting to a position close to the design position, stop, and measure the coordinates of the rods at both ends of the closure to see if they can meet the closure requirements. Step 8: Tension the horizontal cable to adjust the horizontal spacing of the rods at both ends of the joint mouth until the joint requirements are met and continue to lift it to the joint position. Use the adjustment jack on the arch support frame under the cantilever lifting mechanism to assist in fine-tuning the joint mouth angle. When the horizontal spacing, vertical height difference and relative angle of the joint mouth meet the joint requirements, connect and fix the joint mouth rods. When closing the joint, close one end first, and then use the same method to fine-tune the joint mouth at the other end and connect and fix it; Step 9: After the middle long span arch ribs and the arch foot arch ribs at both ends are connected, use hydraulic jacks to stagely release horizontal cables and lift the cable force, so that the arch foot arch ribs and the middle long span arch ribs are not only structurally connected as a whole, but also the internal force of the arch ribs can be smoothly transmitted to the steel trusses along the entire cross-section, completing the arch rib force system conversion, dismantling the arch rib lifting system and assembly brackets, and completing the installation of the arch ribs.

[0014] The present invention has at least the following beneficial effects: 1. In the present invention, the arch foot arch rib and the middle long span arch rib are assembled at a low position on the steel truss, and a cantilever lifting mechanism is arranged at the front end of the arch foot arch rib to lift the middle long span arch rib. Since the arch foot arch rib is relatively low and the front end joint opening is at a relatively low position, the lifting cantilever mechanism only needs to be higher than the joint opening, and the arch support bracket can also serve as the arch foot arch rib assembly bracket. An adjusting jack is arranged on the top of the arch support bracket, and the horizontal cable and vertical cable of the arch rib are used to finely adjust the posture of the arch rib joint opening to achieve the purpose of rapid joint closing of the arch rib. The proposed technical scheme is feasible, and the arch rib assembly is changed from high-altitude operation to low-altitude operation. The arch cantilever lifting mechanism is light and convenient, and the adjustment of the arch rib joint opening is more intelligent and fast, which greatly reduces the construction risk, reduces the construction difficulty, saves the construction cost, and ensures the safety of engineering construction. 2. The lifting device provided in the present invention can stably lift the middle long span arch rib, and in the process of lifting, one end thereof is lifted first to avoid the phenomenon that the center of gravity of the middle long span arch rib is unstable and tilted when the middle long span arch rib is lifted instantly. In addition, the lifting and positioning mechanisms provided at both ends of the middle long span arch rib can relatively position the middle long span arch rib when the middle long span arch rib is lifted steadily, thereby further ensuring the stability of the lifting of the middle long span arch rib. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of assembling the arch rib of a large-span steel truss beam of the present invention; Figure 2 This is a schematic diagram of the cantilever installation state of the large-span steel truss arch rib of the present invention; Figure 3 It is a side view schematic diagram of the cantilever installation state of the large-span steel truss arch rib of the present invention; Figure 4 It is a schematic diagram of the cantilever lifting mechanism of the present invention; Figure 5 This is a schematic diagram of the side view of the arch foot and arch rib structure of the present invention; Figure 6 For the present invention Figure 5 A schematic diagram of the enlarged structure of the middle A area; Figure 7 For the present invention Figure 5 Middle A area enlarged structural side view; Figure 8 This is a schematic diagram of the structure of the lifting and positioning mechanism of the present invention; Fig. 9 It is a schematic diagram of the structure of the guide mechanism of the present invention; Fig.10 It is a schematic diagram of the cross-sectional structure of the side panel of the present invention; Fig.11 This is a schematic diagram of the internal structure of the positioning sleeve of the present invention; Fig.12This is a schematic diagram of the positioning plate structure of the present invention; Fig.13 It is a schematic diagram of the structure of the synchronization component of the present invention.

[0016] In the figure: 1-lattice column; 11-cantilever beam; 12-back cable; 13-lifting jack; 14-lifting cable; 15-wedge-shaped base; 16-temporary pier; 17-bridge pier; 18-lifting box; 2-steel truss; 3-guide mechanism; 301-guide frame; 302-positioning plate; 303-bidirectional threaded rod; 304-synchronous rod; 305-synchronous assembly; 3051-rotating rod; 3052-rotating member; 3053-driving bevel gear; 3054-rotating bevel gear; 3055-rotating motor; 3056-first rotating gear; 3057-second rotating gear; 31-arch foot arch rib; 32-middle long span arch rib; 4-connecting cable; 41-arch foot arch rib assembly bracket; 42-middle span arch rib assembly bracket; 5-lifting positioning Mechanism; 501-side plate; 502-positioning piece; 5021-hydraulic cylinder; 5022-pushing plate; 5023-positioning sleeve; 5024-positioning groove; 5025-electromagnetic coil; 503-detection sleeve; 504-detection piece; 5041-connecting spring; 5042-connecting plate; 5043-detection block; 5044-pressure sensor; 51-under-arch support bracket; 52-wedge-shaped pad; 6-cantilever lifting mechanism; 61-lattice column; 62-cantilever beam; 63-back rope; 64-lifting jack; 65-lifting rope; 66-wedge-shaped base; 7-horizontal rope anchor box; 8-horizontal rope; 9-adjustment device; 91-column top distribution beam; 92-adjustment jack; 93-adjustment jack wedge-shaped pad; 94-rigid pad. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-13A large-span steel truss arch rib cantilever installation lifting equipment comprises a lattice column 1, a cantilever beam 11, a back cable 12, a lifting jack 13 and a lifting cable 15. The lattice column 1 is composed of a steel pipe and a connection system. That is, in this embodiment, two groups of lattice columns 1 are provided. The two groups of lattice columns 1 are respectively located at the two ends of the middle long span arch rib 32, supported on the arch foot arch rib 31, and connected to the arch foot arch rib 31 through a wedge-shaped base 15. The cantilever beam 11 is welded to the lattice column 1, and the back cable 12 is installed at the rear end of the cantilever beam 11 to be pulled back on the steel truss beam 2. The lifting jack 13 is installed on the cantilever beam 11, and one end of the lifting cable 15 passes through the lifting jack 13. It also includes: A lifting box 18, the bottom of the lifting rope 15 is fixedly connected to the lifting box 18; A guide mechanism 3, which is installed on a side of the lifting box 18 close to the lattice column 1, and is used to guide and limit the lifting box 18 when it is lifted; The guide mechanism 3 includes two U-shaped guide frames 301 installed on one side of the lifting box 18, and the two guide frames 301 are respectively slidably sleeved on the outside of the lattice column 1; Grooves are provided on both sides of the guide frame 301, and positioning plates 302 are slidably connected to the grooves. A bidirectional threaded rod 303 is rotatably connected to the guide frame 301, and the two positioning plates 302 are threadedly sleeved on the outside of the bidirectional threaded rod 303. A synchronization rod 304 is installed at one end of the two bidirectional threaded rods 303 located inside the lifting box 18; A synchronization assembly 305 for synchronously driving the two synchronization rods 304 is installed at the lifting box 18; The synchronization assembly 305 includes a rotating rod 3051 rotatably connected to the inside of the lifting box 18, and a rotating member 3052 for driving the rotating rod 3051 is installed at the lifting box 18; The two ends of the rotating rod 3051 are respectively fixedly connected with driving bevel gears 3053, and the outer side of the driving bevel gear 3053 is meshedly connected with a rotating bevel gear 3054, and the two rotating bevel gears 3054 are respectively fixedly installed at one end of the two synchronous rods 304, and a rotating member 3052 for driving the rotating rod 3051 is installed at the lifting box 18. The rotating member 3052 includes a rotating motor 3055 installed at the lifting box 18, and a first rotating gear 3056 is fixedly installed at the output end of the rotating motor 3055. The outer side of the first rotating gear 3056 is meshedly connected with a second rotating gear 3057, and the second rotating gear 3057 is fixedly sleeved on the outer side of the rotating rod 3051; Specific implementation process: During the stable lifting of the middle long span arch rib 32, on the one hand, the lifting box 18 can be stably lifted relative to the lattice column 1 under the limitation of the two U-shaped guide frames 301 to prevent the lifting box 18 from deflecting, and the auxiliary lifting box 18 can be stably moved under the driving of the lifting rope 15 driven by the lifting jack 13; While the lifting box 18 is moving upward stably, the two connecting cables 4 at the bottom thereof drive the middle long span arch rib 32 to move upward stably; On the other hand, when the middle long span arch rib 32 is driven by the lifting jack 13 and moves to the joint closing position through the lifting rope 15 and the lifting box 18, the rotating motors 3055 at the two lifting boxes 18 are operated. When the rotating motors 3055 are operated, the second rotating gear 3057 is driven to rotate through the first rotating gear 3056, and the second rotating gear 3057 drives the rotating rod 3051 to rotate relative to the inside of the lifting box 18. When the rotating rod 3051 rotates, it drives the two driving bevel gears 3053 at both ends to rotate. When the driving bevel gears 3053 rotate, they rotate by rotating the bevel gears 3054, thereby further rotating the corresponding synchronous rod 304. When the synchronous rod 304 rotates, it drives the two-way threaded rod 303 fixed to one end thereof to rotate. The rotation of the two-way threaded rod 303 provides a driving force for the two positioning plates 302 thereon. Because the positioning plates 302 are limited by the grooves, the positioning plates 302 are further moved along the direction of the lattice column 1 until the two positioning plates 302 at the lifting box 18 clamp and fix the lattice column 1 to each other. At this time, the further auxiliary lifting box 18 is fixed relative to the lattice column 1, and at the same time, the middle long span arch rib 32 moved to the joint position further maintains its joint stability when the joint is closed. The connecting rope 4, the lifting box 18 is connected to the two vertical lifting ears at the middle long span arch rib 32 through the two connecting ropes 4 at the bottom, and when the middle long span arch rib 32 is lifted, the lifting jack 13 above one end is operated first, and then the lifting jack 13 above the other end is operated to prevent the middle long span arch rib 32 from tilting due to unstable center of gravity when lifting; The lifting and positioning mechanism 5 is installed at both ends of the lifting box 18, and after the middle long span arch rib 32 is lifted and kept in a horizontal state, the middle long span arch rib 32 is assisted in positioning.

[0019] The lifting and positioning mechanism 5 includes two side plates 501 fixedly mounted on both sides of the lifting box 18, and through holes are provided at the side plates 501, and positioning members 502 are provided through the through holes; The positioning member 502 includes a hydraulic cylinder 5021 fixedly mounted on the lifting box 18, a push plate 5022 is fixedly mounted on the output end of the hydraulic cylinder 5021, the push plate 5022 is located outside the side plate 501, and a positioning sleeve 5023 is fixedly mounted inside the push plate 5022, and the positioning sleeve 5023 is arranged with an internal opening; The positioning sleeve 5023 slides through the through hole, and a positioning groove 5024 is provided at one end of the positioning sleeve 5023 close to its internal opening, and an electromagnetic coil 5025 is installed at the positioning groove 5024; A detection sleeve 503 is provided on the inner side of the side plate 501, and one end of the detection sleeve 503 is fixedly mounted on the outer side of the middle long span arch rib 32; The detection sleeve 503 is provided with a detection member 504 inside, and the detection sleeve 503 detects its relative position through the detection member 504. The detection member 504 includes a connecting spring 5041 fixedly connected to the detection sleeve 503 at one end, and a connecting plate 5042 is fixedly connected to one end of the connecting spring 5041. The connecting plate 5042 is slidably connected to the inside of the detection sleeve 503, and a detection block 5043 is fixedly installed on the side of the connecting plate 5042 away from the connecting spring 5041. The detection sleeve 503 is close to the detection sleeve 503. A moving opening is provided on one side of the proximal plate 501, and the detection block 5043 slides through the moving opening. In this embodiment, the detection block 5043 is connected to the inner side of the detection sleeve 503 under the connecting action of the connecting spring 5041. At the same time, when the middle long span arch rib rotates relative to the side plates 501 on both sides thereof, the detection sleeve 503 does not affect the rotation of the middle long span arch rib, and until the electromagnetic coil 5025 is energized to generate an adsorption force on the detection block 5043, the detection block 5043 moves to the outside of the moving opening. A pressure sensor 5044 is provided inside the detection sleeve 503 and near the moving port. The detection block 5043 is spherical and made of metal iron.

[0020] Specific implementation process: before the middle long span arch rib 32 is lifted upward, the two connecting cables 4 corresponding to the bottom of the two lifting boxes 18 are respectively connected to the vertical lifting ears at the top of the middle long span arch rib 32, and then the lifting jack 13 located above one end of the middle long span arch rib 32 is operated, thereby driving the lifting box 18 to move upward through the lifting cable 15, and when the lifting box 18 moves upward, one end of the middle long span arch rib 32 is subjected to an upward pulling force, so that the force-bearing end is relatively inclined, and then the lifting jack 13 above the other end is operated, and then the lifting jacks 13 at both ends cooperate to operate, so that the middle long span arch rib 32 tilted upward continuously adjusts its center of gravity, until the two lifting jacks 13 run through the lifting cable 15 and the lifting box 18 and the connecting cable 4, so that the middle long span arch maintains a horizontal and stable state, and when its horizontal state is moved upward, it can keep its center of gravity stable, avoiding the phenomenon of unstable center of gravity caused by instantaneous force on both ends of the middle long span arch rib 32 with heavier weight; At the same time, when the middle long span arch rib 32 is kept in a horizontal state, the four positioning sleeves 5023 on the corresponding outer side are moved to the inner side of the side plate 501, and at the same time, the electromagnetic coil 5025 inside the detection sleeve 503 outside the positioning sleeve 5023 is energized, thereby generating an adsorption force on the detection block 5043 located at the detection sleeve 503. As the four detection blocks 5043 move along the corresponding positioning sleeves 5023, the connecting plate 5042 connected to the detection block 5043 contacts the pressure sensor 5044, and the signals of the four pressure sensors 5044 are When the signal values ​​all reach the set values, the electromagnetic coil 5025 is de-energized, and the four hydraulic cylinders 5021 located at the two lifting boxes 18 are synchronously retracted. While retracting, they drive the positioning sleeve 5023 to move through the push plate 5022, and the four positioning sleeves 5023 are respectively moved to the outside of the detection sleeve 503, and one end thereof abuts against the middle long span arch rib, that is, the four positioning sleeves 5023 once again position the middle long span arch rib in the parallel state, thereby ensuring the stability of the upward lifting of the middle long span arch rib.

[0021] A construction method for cantilever installation of a large-span steel truss arch rib using a lifting device for cantilever installation of a large-span steel truss arch rib, comprising the following steps: Step 1: Figure 1 , construct bridge pier 17 and temporary pier 16, and use beam erection crane to erect steel truss beam 2; Step 2: If Figure 1, an arch rib assembly bracket is set up on the erected steel truss 2. The arch rib assembly bracket is divided into three parts, namely two arch foot arch rib assembly brackets 41 and a middle long span arch rib assembly bracket 42. The assembly bracket is reliably connected to the steel truss 2. The assembly brackets are grouped and connected by longitudinal and transverse connection systems to ensure the overall stability of the assembly bracket. For the arch foot arch rib assembly bracket 41, a group of brackets close to the fracture is stronger than the standard assembly bracket, and this bracket is later used as the arch support bracket 51 of the lifting mechanism; Step 3: If Figure 1 , Figure 6 and Figure 7 , a wedge-shaped pad 52 connected to the arch foot arch rib 31 is installed on the top of the rear row of steel pipe columns on the top of the arch support bracket 51, and a distribution beam is installed on the top of the front row of steel pipe columns. Rigid pads 94 are installed at both ends of the distribution beam corresponding to the web positions of the arch foot arch rib 31, and a hydraulic adjustment jack 92 is installed in the middle. A wedge-shaped pad 52 is set on the top of the hydraulic adjustment jack 92 to support the arch foot arch rib 31. In addition, a reinforcement partition is welded within the pressure-bearing range of the lifting bracket inside the arch foot arch rib 31 to ensure that the local force of the arch foot arch rib 31 meets the requirements during lifting; Step 4: Figure 1 , hoist the arch foot arch rib 31 and the middle long span arch rib 32 in blocks on the assembly bracket, the arch foot arch rib 31 and the middle long span arch rib 32 are both composed of small segment arch ribs, the root of the first small segment arch rib of the arch foot arch rib 31 is fixed to the node 2 of the steel truss beam, and the other end is supported on the assembly bracket, and the subsequent small segment arch ribs are also supported by the assembly bracket, and are connected with the previous small segment arch rib according to the designed linearity, so as to form the arch foot arch rib 31 and the middle long span arch rib 32; Step 5: Figure 2 , horizontal cable anchor boxes 7 are provided on the sides of both ends of the middle long span arch rib 32, and the horizontal cable 8 is passed through the anchor box. One end of the middle long span arch rib 32 is the anchoring end, and the horizontal cable 8 is anchored by a special anchor. The other end of the middle long span arch rib 32 is the tensioning end, and the horizontal cable 8 is tensioned by a hydraulic jack. The horizontal cable 8 in the assembled state of the arch rib is tightened. The installation position of the horizontal cable anchor box 7 corresponds to the vertical lifting position. A vertical lifting lug is provided at the top plate of the middle long span arch rib 32 to connect with the connecting cable 4; Step 6: Figure 2 , Figure 5 , install the cantilever lifting mechanism 6 at the front end of the arch foot arch rib 31, pass one end of the lifting cable 15 through the lifting jack 13, use the anchor of the lifting jack 13 to clamp the lifting cable 15, connect the other end of the lifting cable 15 to the lifting box 18, let the lifting cable 15 and the lifting box 18 droop naturally, and connect the lifting box 18 to the middle long span arch rib 32 through the connecting cable 4; Step 7: Figure 2 , Figure 4After the arch foot arch rib 31 and the cantilever lifting mechanism 6 are installed and checked, the horizontal cables 8 on the middle long span arch rib 32 are tensioned in stages, and the coordinates of the joint mouth are measured. The horizontal coordinates of the arch rib end meet the joint closing conditions, and then the lifting jacks 13 and the lifting cables 15 on the cantilever lifting mechanism 6 are used to lift the middle long span arch rib 32. When lifting the middle long span arch rib 32, the lifting jack 13 above one end is operated first, and then the lifting jack 13 above the other end is operated to prevent the middle long span arch rib 32 from tilting due to unstable center of gravity when lifting. During the lifting process, the two lifting jacks 13 cooperate with each other to lift, and under the action of the detection member 504, the middle long span arch rib 32 is lifted upward to keep horizontal, and stopped after lifting to a position close to the design position, and the coordinates of the rods at both ends of the joint mouth are measured again to see if they can meet the joint closing requirements. Step 8: Figure 4 , tension the horizontal cable 8 to adjust the horizontal spacing of the rods at both ends of the joint mouth, and continue to lift it to the joint position until the joint closing requirements are met, and use the adjustment jack 92 on the arch support frame under the cantilever lifting mechanism 6 to assist in fine-tuning the joint mouth angle. When the horizontal spacing, vertical height difference, and relative angle of the joint mouth meet the joint closing requirements, connect and fix the joint mouth rods. When closing the joint, close one end first, and then use the same method to fine-tune the joint mouth at the other end and connect and fix it; Step 9: Figure 4 After the middle long span arch rib 32 and the arch foot arch ribs 31 at both ends are connected, the hydraulic jack is used to release the cable force of the horizontal cable 8 and the lifting cable 15 in stages, so that the arch foot arch rib 31 and the middle long span arch rib 32 are not only structurally connected as a whole, but also the internal force of the arch rib is smoothly transmitted to the steel truss 2 along the entire cross section, completing the force system conversion of the arch rib, dismantling the arch rib lifting system and the assembly bracket, and completing the installation of the arch rib.

[0022] After the steel truss 2 is erected, the arch ribs are installed on the steel truss 2. The whole span of the arch ribs is divided into three sections, of which the arch feet at both ends are short spans and the middle is a long span. The arch ribs 31 at both ends are assembled in situ, and an in situ assembly bracket is set up at the arch feet of the steel truss 2. The front end bracket of the arch rib 31 also serves as a supporting bracket for later lifting. The middle long span arch rib 32 is assembled in low position horizontally, and a low position horizontal assembly bracket is set up in the middle of the steel truss 2 spans. The arch ribs are assembled on the brackets, and an adjusting jack 92 is set on the lower support frame at the front end of the arch foot arch rib 31. A cantilever lifting mechanism 6 is set on the upper part and supported at the front end of the arch rib. A partition is added inside the arch foot arch rib 31 for local reinforcement. The cantilever lifting mechanism 6 is composed of a lattice column 1, a cantilever beam 11, a back cable 12, a lifting jack 13, a lifting cable 15, and a lifting box 18. The back cable 12 is used to pull back on the steel truss beam 2 to ensure the stability of the cantilever lifting mechanism 6 during operation. The two ends of the middle long span arch rib 32 are respectively welded with a horizontal tensioning anchor box and a vertical lifting lug. The horizontal tensioning anchor box is used to tension the horizontal cable 8. One end is the anchor end of the horizontal cable 8, and the other end is the tensioning end of the horizontal cable 8 to ensure the stability of the arch posture of the middle long span arch rib 32 during lifting. After the middle long span arch rib 32 is prompted into place by the cantilever lifting mechanism 6, the horizontal posture of the joint mouth is adjusted by tensioning the horizontal cable 8, and the vertical posture and angle of the joint mouth are adjusted by lifting the vertical cable and adjusting the jack 92 on the arch support frame. First one side is closed, and then the other side. After the arch rib is closed, the arch rib suspension cable is installed to complete the erection of the arch rib.

[0023] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0024] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A large-span steel truss arch rib cantilever installation and lifting device, comprising a lattice column (1), a cantilever beam (11), a back cable (12), a lifting jack (13) and a lifting cable (14), and also comprising: A lifting box (18), wherein the bottom of the lifting rope (14) is fixedly connected to the lifting box (18); A guide mechanism (3), the guide mechanism (3) being mounted on a side of the lifting box (18) close to the lattice column (1), and the guide mechanism (3) being used to guide and limit the lifting box (18) when it is being lifted; The lifting box (18) is connected to two vertical lifting lugs at the middle long span arch rib (32) through two connecting ropes (4) at the bottom, and when the middle long span arch rib (32) is lifted, the lifting jack (13) above one end is operated first, and then the lifting jack (13) above the other end is operated, so as to prevent the middle long span arch rib (32) from tilting due to unstable center of gravity when lifting; A lifting and positioning mechanism (5) is installed at both ends of the lifting box (18) and assists in positioning the middle long span arch rib (32) after the middle long span arch rib (32) is lifted and kept in a horizontal state.

2. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 1, characterized in that: The lattice column (1) is composed of a steel pipe and a connection system, supported on an arch foot and an arch rib (31), and connected to the arch foot and the arch rib (31) via a wedge-shaped base (15). The cantilever beam (11) is welded to the lattice column (1), and is pulled back on the steel truss beam (2) via an installed back cable (12) at the rear end of the cantilever beam (11). The lifting jack (13) is installed on the cantilever beam (11), and one end of the lifting cable (14) passes through the lifting jack (13).

3. The large-span steel truss arch rib cantilever installation lifting equipment according to claim 1, characterized in that: An arch rib assembly bracket is set up on the erected steel truss (2), the arch rib assembly bracket is divided into three parts, namely two arch foot arch rib assembly brackets (41) and a middle long span arch rib assembly bracket (42), the assembly bracket is reliably connected to the steel truss (2), and the assembly brackets are connected in groups through longitudinal and transverse connection systems; A group of brackets of the arch foot and arch rib assembly brackets (41) close to the fracture serve as under-arch support brackets (51) of the lifting mechanism; A wedge-shaped pad (52) connected to the arch foot and arch rib (31) is installed on the top of the rear row of steel pipe columns on the top of the arch support bracket (51), and a distribution beam is installed on the top of the front row of steel pipe columns. Rigid pads (94) are installed at both ends of the distribution beam at positions corresponding to the webs of the arch foot and arch rib (31). A hydraulic adjustment jack (92) is installed in the middle. A wedge-shaped pad (52) is arranged on the top of the hydraulic adjustment jack (92) to support the arch foot and arch rib (31).

4. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 1, characterized in that: The guide mechanism (3) comprises two U-shaped guide frames (301) installed on one side of the lifting box (18), and the two guide frames (301) are respectively slidably sleeved on the outside of the lattice column (1); Grooves are respectively provided on both sides of the guide frame (301), and positioning plates (302) are slidably connected to the grooves. A bidirectional threaded rod (303) is rotatably connected to the guide frame (301), and the two positioning plates (302) are threadedly sleeved on the outside of the bidirectional threaded rod (303). A synchronization rod (304) is installed at one end of the two bidirectional threaded rods (303) located inside the lifting box (18); A synchronization component (305) for synchronously driving two synchronization rods (304) is installed at the lifting box (18).

5. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 4, characterized in that: The synchronization component (305) comprises a rotating rod (3051) rotatably connected to the inside of the lifting box (18); a rotating member (3052) for driving the rotating rod (3051) is installed at the lifting box (18); The two ends of the rotating rod (3051) are respectively fixedly connected to driving bevel gears (3053), and the outer side of the driving bevel gear (3053) is meshingly connected to a rotating bevel gear (3054), and the two rotating bevel gears (3054) are respectively fixedly mounted on one end of the two synchronous rods (304).

6. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 5, characterized in that: The rotating member (3052) comprises a rotating motor (3055) mounted on the lifting box (18); a first rotating gear (3056) is fixedly mounted on the output end of the rotating motor (3055); a second rotating gear (3057) is meshingly connected to the outer side of the first rotating gear (3056); and the second rotating gear (3057) is fixedly sleeved on the outer side of the rotating rod (3051).

7. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 1, characterized in that: The lifting and positioning mechanism (5) comprises two side plates (501) fixedly mounted on both sides of the lifting box (18); the side plates (501) are provided with through holes, and positioning members (502) are provided through the through holes; A detection sleeve (503) is provided on the inner side of the side plate (501), and one end of the detection sleeve (503) is fixedly mounted on the outer side of the middle long span arch rib (32); The detection sleeve (503) is provided with a detection member (504) inside, and the detection sleeve (503) detects its relative position through the detection member (504).

8. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 7, characterized in that: The positioning member (502) comprises a hydraulic cylinder (5021) fixedly mounted on the lifting box (18); a push plate (5022) is fixedly mounted on the output end of the hydraulic cylinder (5021); the push plate (5022) is located outside the side plate (501); and a positioning sleeve (5023) is fixedly mounted inside the push plate (5022); the positioning sleeve (5023) is arranged with an internal opening; The positioning sleeve (5023) slides through the through hole, and a positioning groove (5024) is provided at one end of the positioning sleeve (5023) close to its internal opening, and an electromagnetic coil (5025) is installed at the positioning groove (5024).

9. The large-span steel truss arch rib cantilever installation and lifting equipment according to claim 7, characterized in that: The detection member (504) comprises a connection spring (5041) having one end fixedly connected to the detection sleeve (503); one end of the connection spring (5041) is fixedly connected to a connection plate (5042); the connection plate (5042) is slidably connected inside the detection sleeve (503); a detection block (5043) is fixedly mounted on a side of the connection plate (5042) away from the connection spring (5041); a moving opening is provided on a side of the detection sleeve (503) close to the side plate (501); and the detection block (5043) slides through the moving opening; A pressure sensor (5044) is provided inside the detection sleeve (503) and close to the moving port.

10. The construction method for cantilever installation of a large-span steel truss arch rib using a large-span steel truss arch rib cantilever installation lifting device according to claim 1, characterized in that: The following steps are involved: Step 1: construct bridge piers (17) and temporary piers (16), and erect steel trusses (2) using a beam erection crane; Step 2: erecting an arch rib assembly bracket on the erected steel truss (2); Step 3: Install the under-arch support bracket (51); Step 4: hoisting the arch foot arch rib (31) and the middle long span arch rib (32) in blocks on the assembly bracket, the arch foot arch rib (31) and the middle long span arch rib (32) are both composed of small segment arch ribs, the root of the first small segment arch rib of the arch foot arch rib (31) is fixed to the node of the steel truss (2), and the other end is supported on the assembly bracket, and the subsequent small segment arch ribs are also supported by the assembly bracket and connected with the previous small segment arch rib according to the designed linearity, so as to form the arch foot arch rib (31) and the middle long span arch rib (32); Step 5: Horizontal cable anchor boxes (7) are provided on the sides of both ends of the middle long span arch rib (32), and the horizontal cable (8) is passed through the anchor box. One end of the middle long span arch rib (32) is the anchoring end, and the horizontal cable (8) is anchored by a special anchor. The other end of the middle long span arch rib (32) is the tensioning end. The horizontal cable (8) is tensioned by a hydraulic jack. The horizontal cable (8) in the assembled state of the arch rib is tightened. The installation position of the horizontal cable anchor box (7) corresponds to the vertical lifting position. A vertical lifting lug is provided at the top plate of the middle long span arch rib (32) to connect with the connecting cable (4); Step 6: Install a cantilever lifting mechanism (6) at the front end of the arch foot arch rib (31), pass one end of the lifting cable (14) through the lifting jack (13), use the anchor of the lifting jack (13) to clamp the lifting cable (14), connect the other end of the lifting cable (14) to the lifting box (18), let the lifting cable (14) and the lifting box (18) droop naturally, and connect the lifting box (18) to the middle long span arch rib (32) through the connecting cable (4); Step 7: After the arch foot arch rib (31) and the cantilever lifting mechanism (6) are installed and checked, the horizontal cables (8) on the middle long span arch rib (32) are tensioned in stages, and the coordinates of the joint mouth are measured. The horizontal coordinates of the arch rib end meet the joint closing conditions, and then the lifting jacks (13) and lifting cables (14) on the cantilever lifting mechanism (6) are used to lift the middle long span arch rib (32). When lifting the middle long span arch rib (32), the lifting jack (13) above one end is operated first, and then the lifting jack (13) above the other end is operated to prevent the middle long span arch rib (32) from tilting due to unstable center of gravity when lifting. During the lifting process, the two lifting jacks (13) cooperate with each other to lift, and under the action of the detection member (504), the middle long span arch rib (32) is lifted upward to maintain horizontality. After lifting to a position close to the design position, stop, and measure again whether the coordinates of the rods at both ends of the joint mouth meet the joint closing requirements; Step 8: tensioning the horizontal cable (8) to adjust the horizontal spacing of the rods at both ends of the joint mouth until the joint closing requirements are met and then continue to lift to the joint closing position, using the adjustment jack (92) on the arch support frame under the cantilever lifting mechanism (6) to assist in fine-tuning the joint mouth angle, when the horizontal spacing, vertical height difference and relative rotation angle of the joint mouth all meet the joint closing requirements, the joint mouth rods are connected and fixed, and when closing the joint, one end is closed first, and then the joint mouth at the other end is fine-tuned in the same way and connected and fixed; Step 9: After the middle long span arch rib (32) and the arch foot arch ribs (31) at both ends are connected, the hydraulic jack is used to release the cable forces of the horizontal cables (8) and the lifting cables (14) in stages, so that the arch foot arch rib (31) and the middle long span arch rib (32) are not only structurally connected as a whole, but also the internal force of the arch rib is smoothly transmitted to the steel truss (2) along the entire cross section, completing the transformation of the arch rib's force system, dismantling the arch rib lifting system and the assembly bracket, and completing the installation of the arch rib.

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