Temporary sling device for dismantling of a suspension bridge boom

Abstract

The application relates to a temporary sling device for suspender dismantling of a suspension bridge, which only needs to weld two longitudinal anti-skid blocks on an arch rib, reduces welding quantity compared with a traditional method, avoids large-area heat-affected damage to the arch rib structure, hangs a flexible sling behind the anti-skid blocks, uniformly transmits loads to a temporary suspender through a bottom cross beam, forms a force flow path of the arch rib, the flexible sling, the cross beam and the temporary suspender, and avoids local stress concentration; then a bridge deck pole beam directly receives temporary suspender loads and disperses the loads to the bridge deck; the bridge deck pole beam is connected with a tensioning assembly to form a closed stress frame, actively bears the bridge deck load after the suspender is unloaded, prevents the bridge deck from sinking, reduces the amount of high-altitude welding operation, improves installation efficiency, and the load transmission path is clear, and safety is significantly improved.

Description

Technical Field

[0001] This application relates to the field of bridge maintenance technology, and in particular to a temporary hoisting device for dismantling suspension bridge suspenders. Background Technology

[0002] In recent years, steel-concrete composite arch bridges have experienced rapid development due to their advantages such as high material strength, convenient construction, and aesthetically pleasing design. As a key force-transmitting component in mid- and under-deck steel-concrete composite arch bridges, hangers are often made of flexible high-strength steel wire or strand. Hangers are typically designed as replaceable components with a design life of 20 years. However, due to insufficient consideration during early construction, inadequate routine maintenance, and the effects of external loads and the environment, the actual service life of hangers is far shorter than their design life, making them highly susceptible to damage. In recent years, there have been several incidents of hanger breakage in arch bridges in China, necessitating timely replacement of these hangers. Currently, several arch bridges in China have undergone hanger replacement work, and it is expected that as their service life extends, more and more arch bridges will require hanger replacement.

[0003] In the past, temporary hoisting was often used to replace the suspenders. This method required welding a large number of steel wedges and distribution beams onto the arch, which involved a large amount of welding work and was complicated to operate. Summary of the Invention

[0004] This application provides a temporary hoisting device for dismantling suspension bridge suspenders, which solves the problem that in related technologies, the temporary hoisting method is often used for suspender replacement, which requires welding a large number of steel wedges and distribution beams on the arch, resulting in a large amount of welding work and complicated operation.

[0005] In a first aspect, a temporary lifting device for dismantling suspension bridge suspenders is provided, comprising: An anti-slip structure comprising two longitudinally spaced anti-slip blocks welded to the arch rib; Two flexible slings are respectively hung on the corresponding anti-blocking blocks. The flexible slings are used to set on both sides of the longitudinal direction of the lifting rod to be removed. The bottom of each flexible sling is connected to a crossbeam. The bottom of the crossbeam is connected to a temporary lifting rod. Two bridge deck spreader beams are located above the bridge deck and are connected to the bottom of two temporary hangers one by one; Two under-bridge spreader beams are located under the bridge; each under-bridge spreader beam is connected to the corresponding bridge deck spreader beam through two tensioning components to bear the bridge deck load after the suspenders to be removed are unloaded.

[0006] In some embodiments, the flexible sling is a high-strength fiber sling or a steel wire rope.

[0007] In some embodiments, the flexible sling has a designed width.

[0008] In some embodiments, the crossbeam is provided with a first pin hole; Both ends of the flexible sling are provided with connecting blocks, and the connecting blocks are provided with second pin holes; a pin is connected in the second pin hole; the pin is also connected to the crossbeam through the first pin hole.

[0009] In some embodiments, both ends of the bridge deck spreader beam and the under-bridge spreader beam are provided with vertical through holes; The tensioning assembly includes a tensioning rod and a tensioning support frame; the tensioning support frame is installed on the top surface of the bridge deck spreader beam, and a through-hole jack is provided on it; The bottom end of the tension rod is anchored to the vertical through hole of the bridge deck beam; the top end of the tension rod is sequentially inserted through the bridge deck, the vertical through hole of the bridge deck beam, the tensioning support frame and the through-hole jack, and connected to the top of the through-hole jack.

[0010] In some embodiments, a pad and an anchor nut are stacked on top of the through-hole jack; the tension rod passes through the pad and the anchor nut and is threadedly connected to the anchor nut.

[0011] In some embodiments, the tensioning brace is provided with a precision-rolled nut in the space through which the tensioning rod passes; the tensioning rod passes through the precision-rolled nut and is threadedly connected to the precision-rolled nut.

[0012] In some embodiments, a transverse support structure is provided within the space formed by the flexible sling and below the arch rib, and the two ends of the transverse support structure are provided with through slots for the flexible sling to pass through; the length of the transverse support structure is greater than the diameter of the arch rib.

[0013] In some embodiments, the lateral support structure includes a lateral member with pulleys on both sides of the lateral side for contacting the flexible sling.

[0014] In some embodiments, the transverse member is welded to the arch rib or connected by magnetic attraction.

[0015] The beneficial effects of the technical solution provided in this application include: This application provides a temporary lifting device for dismantling suspension bridge suspenders. Since only two longitudinal anti-slip blocks need to be welded to the arch rib, the amount of welding is reduced compared to traditional methods, avoiding large-area heat-affected damage to the arch rib structure. A flexible sling is attached to the anti-slip blocks, and the load is evenly transferred to the temporary suspender through the bottom crossbeam, forming a force flow path between the arch rib, flexible sling, crossbeam, and temporary suspender, avoiding localized stress concentration. Then, the bridge deck spreader beam directly bears the load of the temporary suspender, distributing it to the bridge deck. A tensioning component connects to the bridge deck spreader beam, forming a closed load-bearing frame that actively bears the bridge deck load after the suspender is unloaded, preventing bridge deck subsidence. This reduces the amount of high-altitude welding work, improves installation efficiency, and significantly enhances safety due to the clear load transfer path. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a front view of a temporary hoisting device for dismantling suspension bridge suspenders provided in an embodiment of this application; Figure 2 Left view of the temporary hoisting device for dismantling suspension bridge gantry provided in the embodiments of this application; Figure 3 Provided for the embodiments of this application Figure 2 Enlarged diagram of point A in the middle.

[0018] In the diagram: 1. Arch rib; 2. Anti-sliding block; 3. Flexible sling; 4. Hanger to be dismantled; 5. Crossbeam; 6. Temporary hanger; 7. Bridge deck spreader beam; 8. Under-bridge spreader beam; 9. Tensioning assembly; 900. Tensioning rod; 901. Tensioning support frame; 902. Through-hole jack; 903. Pad; 904. Anchor nut; 905. Precision rolled nut; 10. Transverse top support structure. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This application provides a temporary hoisting device for dismantling suspension bridge suspenders, which solves the problem that the temporary hoisting method is often used for suspender replacement in related technologies. This method requires welding a large number of steel wedges and distribution beams on the arch, resulting in a large amount of welding work and complicated operation.

[0021] Please see Figures 1 to 2 A temporary hoisting device for dismantling suspension bridge suspenders, comprising: An anti-slip structure comprising two longitudinally spaced anti-slip blocks 2 welded to the arch rib 1; Two flexible slings 3 are respectively hung on the corresponding anti-blocking blocks 2. The flexible slings 3 are used to set on both sides of the longitudinal direction of the lifting rod 4 to be removed. The bottom of each flexible sling 3 is connected to a crossbeam 5. The bottom of the crossbeam 5 is connected to a temporary lifting rod 6. Two bridge deck spreader beams 7 are located above the bridge deck and are connected one-to-one to the bottom of two temporary hangers 6; Two under-bridge spreader beams 8 are located under the bridge; each under-bridge spreader beam 8 is connected to the corresponding bridge deck spreader beam 7 through two tensioning components 9 to bear the bridge deck load after the hanger 4 is unloaded.

[0022] Using the above-described device, only two longitudinal anti-blocking blocks need to be welded to the arch rib, reducing the amount of welding compared to traditional methods and avoiding large-area heat-affected damage to the arch rib structure. After the flexible sling is hung on the anti-blocking block, the load is evenly transferred to the temporary hanger through the bottom crossbeam, forming a force flow path of arch rib, flexible sling, crossbeam, and temporary hanger, avoiding local stress concentration. Then, the bridge deck spreader beam directly bears the load of the temporary hanger and distributes it to the bridge deck. The tensioning component is connected to the bridge deck spreader beam to form a closed force-bearing frame, which actively bears the bridge deck load after the hanger is unloaded, preventing the bridge deck from sinking. This reduces the amount of high-altitude welding work, improves installation efficiency, and the load transfer path is clear, significantly improving safety. The specific construction method will be explained later.

[0023] In some preferred embodiments, the flexible sling 3 is a high-strength fiber soft sling or a steel wire rope; the flexible sling 3 has a designed width.

[0024] Among them, high-strength fiber slings are lightweight, making manual handling highly efficient; they have excellent flexibility, conforming to the curved surface of arched ribs and avoiding localized compression damage to the anti-corrosion layer; they are insulating and corrosion-resistant, suitable for humid environments. Steel wire ropes have strong abrasion resistance, suitable for friction conditions that may occur during the dismantling of the sling; they have a high modulus of elasticity, allowing for precise deformation control.

[0025] Materials can be flexibly selected according to the bridge's working conditions (such as corrosive environment and load size), taking into account both economy and adaptability.

[0026] The above-mentioned flexible sling 3 is too narrow, which can easily lead to excessive local compressive stress on the arch rib, causing coating damage or plastic deformation of the steel structure. The optimal width (usually 200-400mm) can be determined by finite element analysis, so that the contact pressure is ≤5MPa (lower than the allowable stress of the arch rib), while meeting the following conditions: dispersing pressure and protecting the arch rib; providing a sufficient friction coefficient to prevent sling slippage (friction coefficient ≥0.25); and controlling the sling's self-weight to avoid excessively increasing the construction burden.

[0027] In some preferred embodiments, the crossbeam 5 is provided with a first pin hole; Both ends of the flexible sling 3 are equipped with connecting blocks, and the connecting blocks have second pin holes; a pin is connected in the second pin hole; the pin is also connected to the crossbeam 5 through the first pin hole. The first pin hole + second pin hole + pin forms a rigid hinge node, allowing the sling to swing slightly to adapt to the angle and avoid bending stress; the end of the sling is vulcanized and sealed in the metal connecting block to prevent wear on the end of the sling.

[0028] In some preferred embodiments, both ends of the bridge deck spreader beam 7 and the under-bridge spreader beam 8 are provided with vertical through holes; The tensioning assembly 9 includes a tension rod 900 and a tensioning support 901. The tensioning support 901 is installed on the top surface of the bridge deck spreader beam 7, and a through-hole jack 902 is provided on it. The bottom end of the tension rod 900 is anchored to the vertical through hole of the bridge deck spreader beam 8. The top end of the tension rod 900 passes sequentially through the bridge deck, the vertical through hole of the bridge deck spreader beam 7, the tensioning support 901, and the through-hole jack 902, and is connected to the top of the through-hole jack 902. A pad 903 and an anchoring nut 904 are stacked on the top of the through-hole jack 902. The tension rod 900 passes through the pad 903 and the anchoring nut 904 and is threadedly connected to the anchoring nut 904. A precision nut 905 is provided in the space through which the tensioning support 901 passes the tension rod 900. The tension rod 900 passes through the precision nut 905 and is threadedly connected to the precision nut 905.

[0029] The through-hole jack 902 is fixed to the top of the bridge deck spreader beam 7, shifting the operating space from under the bridge to the bridge deck, thus improving safety; the through-hole jack 902 directly tensions the vertically penetrating tension rod 900, and the anchoring path of the tension rod 900 is as follows: The bottom anchor beam 8 under the bridge passes through the bridge deck and the bridge deck beam 7, and is locked by the top of the jack to form a closed tension ring; single-point tensioning can synchronously adjust the load balance on both sides, solving the problem of asynchronous operation of traditional multi-jacks; the tension force is adjustable in real time, dynamically compensating for the bridge deck deformation after the suspenders are unloaded.

[0030] Among them, the design of pad 903 and anchor nut 904 ensures long-term load-bearing reliability, and pad 903 increases the top contact area of ​​the through-hole jack 902 to disperse local pressure; Anchor nut 904 and precision rolled nut 905 form a double-nut anti-loosening structure to resist the loss of preload caused by vehicle vibration; the secondary locking of precision rolled nut 905 solves the stability problem of tension rod and reduces the long-term load loss of the through-hole jack. In addition, it can also make the through-hole jack 902 detachable for use at other tensioning points, thus improving equipment utilization.

[0031] In some embodiments, a transverse support structure 10 is provided within the space formed by the flexible sling 3 and below the arch rib 1. The two ends of the transverse support structure 10 are provided with through slots for the flexible sling 3 to pass through. The length of the transverse support structure 10 is greater than the diameter of the arch rib 1.

[0032] The transverse support structure 10 includes a transverse member, on both sides of the transverse member for contacting the flexible sling 3.

[0033] The transverse component is welded to the arch rib 1 or connected by magnetic attraction.

[0034] In this embodiment, the lateral support structure eliminates the risk of inward tilting of the flexible sling, and the through-slot allows the sling to pass freely while restricting lateral displacement; the length is greater than the diameter of the arch rib: ensuring that the end point of the support exceeds the projection range of the arch rib, forming a reaction arm; when the sling contracts inward after being loaded, the support structure provides a reverse support force, reducing friction between the sling and the arch rib; and preventing stress concentration caused by an excessively small sling angle.

[0035] The pulley contact mode achieves zero friction loss. Traditional steel-fiber slings have a sliding friction coefficient of about 0.3, resulting in a tension loss of 5-8%. The pulley design can reduce the friction coefficient. The pulley material is MC nylon, which has moderate hardness to avoid damaging the sling surface. When the sling angle changes, the pulley rotates automatically to eliminate torsional load.

[0036] Among them, the magnetic connection scheme overcomes the limitations of welding, which damages the arch rib coating due to the high temperature of welding and generates residual stress; magnetic adsorption can use neodymium iron boron permanent magnets to meet the anti-overturning requirements; thus, it can achieve rapid installation and disassembly and avoid hot work; it causes zero damage to the arch rib anti-corrosion layer and is especially suitable for stainless steel arch ribs; welding is suitable for non-magnetic arch ribs such as aluminum alloys, making the lifting device universal.

[0037] The steps for dismantling the hanger are as follows: Step 1: Equipment installation preparation; accurately position the two longitudinal anti-slip blocks 2 on the arch ribs 1 on both sides of the boom to be replaced; then select high-strength fiber slings or steel wire ropes and hang them on the anti-slip blocks 2 according to the design width.

[0038] Step 2: Installation of the bridge deck-underpass system; The crossbeam 5 is quickly hinged to the bottom end of the flexible sling 3 via a pin; the bridge deck spreader beam 7 is placed on the bridge deck and anchored to the temporary suspender 6; the under-bridge spreader beam 8 is connected to the bridge deck spreader beam 7 via the tensioning assembly 9.

[0039] That is, the bottom end of the tension rod 900 is anchored to the bridge's under-bracing beam 8, and the top end passes through the following: Bridge deck → Bridge deck spreader beam 7 through holes → Tensioner support 901 → Through jack 902 → Pad 903 → Anchor nut 904; The through-hole jack 902 is activated to apply 10% of the design tension force to eliminate structural gaps; the precision rolled nut 905 is initially tightened to bear the temporary load.

[0040] Step 3: Load transfer and staged tensioning; The 902-stage through-hole jack operates on a three-stage loading configuration: 40%→80%→100%, with simultaneous control of the stroke difference between the jacks on both sides. Tensioning to 40%: The tension of the old 4-cable suspension rod decreased by 30%; Tensioning to 100%: The old suspenders are completely unloaded, and the bridge deck load is borne by the temporary hoisting device.

[0041] The bridge deck elevation changes are monitored in real time, and the tension is adjusted if the elevation exceeds the limit.

[0042] Step 4: Remove the old hanger rods; intervene with the horizontal top support structure. Install a transverse component with pulleys within the flexible sling 3 space to control the sling angle and prevent inward friction; cut the old sling into three sections, with each section slowly lowered using a winch; during cutting, the transverse top support structure bears the horizontal component of the sling force to prevent swaying.

[0043] Step 5: Lift and position the new suspender; using the bridge's under-span beam 8 as the lifting fulcrum, install the new suspender and tension it to the design cable force. Release the temporary tension in stages: 100% → 50% → 0%, simultaneously increasing the cable force of the new suspender.

[0044] Step 6: Remove the device.

[0045] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0046] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0047] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A temporary hoisting device for dismantling suspension bridge suspenders, characterized in that, It includes: The anti-slip structure includes two longitudinally spaced anti-slip blocks (2) welded to the arch rib (1). Two flexible slings (3) are respectively hung on the corresponding anti-blocking blocks (2). The flexible slings (3) are used to set on both sides of the longitudinal direction of the lifting rod (4) to be removed. A crossbeam (5) is connected to the bottom of each flexible sling (3). A temporary lifting rod (6) is connected to the bottom of the crossbeam (5). Two bridge deck spreader beams (7) are located above the bridge deck and are connected one-to-one with the bottom of two temporary hangers (6); Two under-bridge spreader beams (8) are located under the bridge; each under-bridge spreader beam (8) is connected to the corresponding bridge deck spreader beam (7) by two tensioning components (9) to bear the bridge deck load after the hanger (4) is unloaded.

2. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 1, characterized in that: The flexible sling (3) is a high-strength fiber soft sling or a steel wire rope.

3. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 1, characterized in that: The flexible sling (3) has a designed width.

4. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 1, characterized in that: The crossbeam (5) is provided with a first pin hole; Both ends of the flexible sling (3) are provided with connecting blocks, and the connecting blocks are provided with second pin holes; a pin is connected in the second pin hole; the pin is also connected to the crossbeam (5) through the first pin hole.

5. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 1, characterized in that: Both ends of the bridge deck spreader beam (7) and the under-bridge spreader beam (8) are provided with vertical through holes; The tensioning assembly (9) includes a tensioning rod (900) and a tensioning support (901); the tensioning support (901) is installed on the top surface of the bridge deck spreader beam (7) and is provided with a through-hole jack (902). The bottom end of the tension rod (900) is anchored to the vertical through hole of the bridge deck beam (8); the top end of the tension rod (900) is sequentially inserted through the vertical through hole of the bridge deck beam (7), the tensioning support (901), and the through jack (902), and is connected to the top of the through jack (902).

6. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 5, characterized in that: The top of the through-hole jack (902) is stacked with a pad (903) and an anchor nut (904); the tension rod (900) passes through the pad (903) and the anchor nut (904) and is threadedly connected to the anchor nut (904).

7. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 6, characterized in that: The tensioning support frame (901) is provided with a precision nut (905) in the space through which the tensioning rod (900) passes; the tensioning rod (900) is threaded through the precision nut (905) and connected to the precision nut (905) by threads.

8. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 1, characterized in that: Within the space formed by the flexible sling (3), and below the arch rib (1), there is a transverse top support structure (10), and at both ends of the transverse top support structure (10) are through grooves for the flexible sling (3) to pass through; the length of the transverse top support structure (10) is greater than the diameter of the arch rib (1).

9. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 8, characterized in that: The transverse support structure (10) includes a transverse member, and pulleys for contacting the flexible sling (3) are provided on both sides of the transverse member.

10. The temporary hoisting device for dismantling suspension bridge suspenders as described in claim 9, characterized in that: The transverse member is welded to the arch rib (1) or connected by magnetic adsorption.

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