Liftable support for replacing lower cushion block of portable walking jack

Abstract

The invention discloses a convenient lifting type support for replacing a lower cushion block of a walking type jack, and relates to the field of bridge construction equipment. The support comprises a walking type jack used for supporting the steel box girder, a supporting plate used for bearing the jack, a door type support arranged on the outer side of the jack, and a hoist crane fixed to a top frame of the door type support. The portal support achieves height adjustment through nesting fit of the lower support sleeve and the upper support sleeve, the hoist crane is connected with the abutment and the supporting plate through the chain, and the retractable chain drives the supporting plate and the jack to ascend and descend. The invention further discloses an operation method of the device, and the operation is completed by assembling the device, pushing the steel box girder, lifting the supporting plate to replace the cushion block and resetting the jack. The support does not need large equipment, is convenient to operate and accurate in positioning, can efficiently complete replacement of the lower cushion block of the jack, is adaptive to different abutment heights and construction scenes, reduces the cost, and improves the construction safety and efficiency.

Description

Technical Field

[0001] This invention relates to a device for bridge engineering using the jacking method, and more particularly to a convenient, movable support for replacing the lower pad of a walking jack. Background Technology

[0002] The incremental launching method for bridge construction was first applied to the Agger Bridge in Austria in 1959 by Professors Leonhardt and Bauer of Germany. Its core principle involves precast concrete beam segments or steel box girders behind the abutments and then using horizontal jacks to push them segment by segment to their designed positions. This method has advantages such as not requiring large scaffolding, high site utilization, and the ability to be constructed year-round, but its cost is higher than that of traditional simply supported beams and cast-in-place continuous beams.

[0003] Currently, before the steel beam's front height-adjusting section is pushed to the temporary pier's rear support point, triangular inclined pads and transition pads are installed at the bottom of the beam, such as... Figure 1 , 2 As shown. During the first jacking, the jacking equipment is activated to evenly lift the steel beam to a safe height, and then it is moved forward a distance L1. After moving into position, one set of transition pads K is removed, and a short column Z3 is installed on the rear support point of the temporary pier (as a more stable long-term support structure). The beam is slowly lowered, so that the steel beam transitions from being supported by triangular inclined pads and the remaining transition pads K to being supported by triangular inclined pads and short column Z3. During the second jacking, the jacking equipment is activated again to lift the steel beam and move it forward a distance L2. The beam is lowered to the temporary support state, and the remaining three sets of transition pads K at the bottom of the beam are removed. The walking jacks are raised (the height of the jacks is adjusted to adapt to the new support), and a short column Z3 is added at the middle support point. The walking jacks are slowly lowered so that the steel beam is finally supported by the triangular inclined pads, the rear support point, and the middle support point Z3, completing the support adjustment for this stage.

[0004] During the box girder lifting stage, jacks are used to evenly lift the box girder off its original supports, temporarily placing it on safety steel piers. During lifting, ensure the gap between the girder and the support is kept within 2cm, alternating between intermediate supports, and strictly prohibit lowering the girder between adjacent supports. When replacing the shims, the hydraulic pressure of the two jacks at the same end of the girder is controlled to ensure even force distribution and prevent three-legged support. When replacing the shims, first lift the jacks to an appropriate height, then carefully remove the old shims, insert the new shims, and finally slowly lower the jacks to ensure even force distribution on the new shims.

[0005] During bridge jacking construction, the number of steel pads under the walking jacks needs to be adjusted according to the longitudinal alignment of the bridge. The operation procedure is as follows: (1) lift the walking jacks, (2) add or remove steel pads under the walking jacks, and (3) lower the walking jacks. Walking jacks generally weigh about 1.5t, making lifting and lowering them difficult. Moreover, they are not suitable for the narrow working space around bridge piers and are not suitable for setting up large, heavy equipment.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a convenient, adjustable support for replacing the lower pad of a walking jack. This support can stably raise and lower the jack, is compatible with pad replacement, and has a simple structure.

[0008] To achieve the above objectives, the present invention provides a convenient, adjustable support for replacing the lower pad of a walking jack, comprising: A walking jack is used to support a steel box girder. The walking jack includes a vertical pushing mechanism and a translational pushing mechanism. A pallet is provided on which the walking jack is placed, a pad is provided under the pallet, and a hook ring is provided on the pallet. A portal frame is installed on the outside of the walking jack. The portal frame includes a top frame, a lower support sleeve, and an upper support sleeve. Four upper support sleeves are provided below the four corners of the top frame. There are four lower support sleeves and a base plate at the bottom. Both the lower support sleeve and the upper support sleeve are hollow tubular structures with multiple positioning holes. The lower support sleeve is fitted into the upper support sleeve and fixed by inserting fixing bolts into the positioning holes. The hoist is fixed on the top frame of the gantry frame. The hoist is equipped with an upper hook, a chain, and a lower hook. The upper hook engages with the hook hole of the top frame. One end of the chain is fixed to the platform, and the other end is connected to the hook ring of the pallet through the lower hook. The pallet and the walking jack are raised and lowered by raising and lowering the chain. In one embodiment of the present invention, the hook ring of the pallet is disposed on the edge of the upper surface of the pallet.

[0009] In one embodiment of the present invention, the top frame is a rectangular frame structure, and the gourd hook holes are arranged on the four sides of the top frame. In one embodiment of the present invention, the hoist is a manual or electric hoist. In one embodiment of the present invention, two hoists are provided on each of the left and right side borders of the top frame and are symmetrically distributed along the length of the borders, and one hoist is provided on each of the front and rear side borders of the top frame and is located at the midpoint of the border. In one embodiment of the present invention, the hoists on the left and right sides of the pallet can return the pallet to its initial position before translation by controlling the chain length. In one embodiment of the present invention, the height adjustment range of the portal frame is 1.2-3.5m. The present invention also provides a method for replacing a liftable support using the aforementioned convenient walking jack under pad, characterized by comprising the following steps: S1: Assemble the gantry frame, hoist and pallet, connect the lower hook of the hoist to the hook ring of the pallet, the pallet supports the walking jack and places pad blocks, and fix the gantry frame to the pier. S2: The steel box girder is pushed by the vertical pushing mechanism of the walking jack, and then the steel box girder is moved horizontally by the translation pushing mechanism; S3: Control the vertical pushing mechanism to retract so that the jack is separated from the steel box girder, start the hoist chain to lift the pallet, adjust the pallet to the initial position and then place the additional pad block; S4: Operate the hoist to release the chain, allowing the pallet to lower onto the new pad using the jack, completing the replacement. In one embodiment of the invention, in step S3, the hoists on both sides of the pallet can return the pallet to its initial position before translation by controlling the chain length.

[0010] Compared with existing technologies, the convenient walking jack pad replacement liftable support according to the present invention has the following advantages: First, it has a high degree of structural integration, organically integrating the walking jack, pallet, gantry support, and hoist. It eliminates the need for external large equipment, allowing pad replacement to be completed solely through component coordination, significantly simplifying construction equipment configuration. It is suitable for the confined working space around bridge piers and solves the pain point of traditional pad replacement requiring multiple pieces of equipment. Second, it is convenient to operate and has precise positioning. The gantry support uses sleeves and bolts for height adjustment, adapting to different pier heights. The hoist's chain can precisely raise and lower the pallet, and the chain control of the hoists on both sides allows the pallet to return to its initial position, preventing jack misalignment and ensuring construction quality. The time required for replacing a single pad is reduced by more than 60% compared to traditional methods. Thirdly, it boasts superior safety and economy. The support frame stands stably on the pier, and the hoist hook is equipped with a locking device, eliminating the need for personnel to enter the danger zone below the jack, thus reducing safety hazards. The core components are reusable and are compatible with both light and heavy jacks as well as various construction scenarios, combining practical value with promotional potential. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the installation position of a convenient walking jack lower pad replacement liftable bracket according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a conventional bridge jacking construction method according to an embodiment of the present invention; Figure 3 This is a structural schematic diagram of a convenient walking jack lower pad replacement liftable support according to an embodiment of the present invention. Figure 4 This is a side view of a convenient walking jack with a liftable support for replacing the lower pad block, according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the structure of a portal frame according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of a walking jack according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of a tray according to an embodiment of the present invention; Figure 8 This is a convenient walking jack lower pad replacement liftable support according to an embodiment of the present invention.

[0012] Explanation of key figure labels: 1-Steel box girder, 2-Pier, 3-Walking jack, 4-Padded block, 41-Added pad, 5-Gantry support, 51-Base plate, 52-Lower support sleeve, 53-Fixing bolt, 54-Upper support sleeve, 55-Top frame, 56-Cycle hook hole, 6-Lifting hoist, 61-Upper hook of hoist, 62-Lower hook of hoist, 7-Panel, 71-Hook ring. Detailed Implementation

[0013] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0014] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0015] like Figure 1 As shown, according to a preferred embodiment of the present invention, a convenient walking jack with a replaceable and liftable support for the lower pad block is installed on the pier 2 during operation, and its jack is used to support the steel box girder 1.

[0016] like Figures 2 to 7 As shown, a convenient walking jack with replaceable and liftable support for the lower pad of the present invention includes a walking jack 3, a gantry bracket 5, and a hoist 6. The walking jack 3 is placed on a support plate 7, and a pad 4 is provided below the support plate 7. The gantry bracket 5 is located on the outside of the walking jack 3. The sprocket of the hoist 6 is fixed to the gantry bracket 5. The lifting hook of the hoist 6 is connected to the support plate 7, which can lift the support plate 7.

[0017] The walking jack 3 includes a vertical pushing mechanism and a translating pushing mechanism. The main function of the vertical pushing mechanism is to lift the steel box girder 1, allowing it to detach from the temporary support beam and transfer it from the support beam to the support of the jacking device, thus facilitating subsequent translation operations. The translating pushing mechanism moves the walking jack 3 back and forth by pushing the front and rear concrete limit blocks on the horizontal plane, thereby achieving the translation function of the steel box girder 1.

[0018] The gantry frame 5 includes a top frame 55, lower support sleeves 52, and upper support sleeves 54. The top frame 55 is a rectangular frame structure, with four upper support sleeves 54 located at its four corners. There are also four lower support sleeves 52, each with a base plate 51 at its bottom to increase the contact area with the ground and improve stability. Both the lower support sleeves 52 and the upper support sleeves 54 are hollow tubular structures with multiple equally spaced positioning holes along their length for inserting fixing bolts 53. The lower support sleeves 52 can be fitted inside the upper support sleeves 54. The relative positions of the lower support sleeves 52 and upper support sleeves 54 are fixed by inserting the fixing bolts 53 into the positioning holes. The height of the top frame 55 is adjusted by adjusting the insertion height of the fixing bolts 53 into the positioning holes.

[0019] The hoist 6 can transmit power by raising and lowering the chain it is linked to. Preferably, two hoists are respectively provided on the left and right sides of the top frame 55 (in the direction of extension of the translation push mechanism of the walking jack 3) and symmetrically distributed along the length of the frame, and one hoist is provided on the front and rear sides respectively.

[0020] The top frame 55 has hoist hook holes 56 on all four sides for mounting the hoist 6. The pallet 7 is provided with a hook ring 71, preferably located on the edge of the upper surface of the pallet 7, and its position corresponds to the hoist hook hole 56.

[0021] The hoist 6 is equipped with an upper hook 61 for suspension in the hook hole 56. One end of the chain of the hoist 6 is fixed to the platform 2, and the other end is equipped with a lower hook 62, which matches the hook ring 71 of the pallet 7. By opening the hoist 6, the pallet 7 can be raised or lowered, thereby raising or lowering the walking jack 3. Through this structure, the present invention uses the gantry frame 5 as a fixed fulcrum, and through the chain drive of the hoist 6, achieves precise raising and lowering of the walking jack 3 with the aid of the pallet 7, solving the height adjustment needs during jack installation, debugging, or pad replacement. The height adjustment range of the gantry frame 5 is 1.2-3.5m.

[0022] During operation, the hoists 6 on the left and right sides of the pallet 7 can return the pallet 7 to its initial position before translation by controlling the chain length.

[0023] The 6-type lifting hoist can be manual or electric. The manual version is small in size, with an inverted triangular shell, and is equipped with a double chain (a thin hand chain for pulling and a thicker lifting chain for load-bearing). The upper hook has a spring-loaded locking baffle and is driven by a manual chain pull. It is suitable for jacks up to 3 tons and is ideal for confined spaces and intermittent operations. The electric version is larger in size, with an integrated design of motor, gearbox, and drum, and an independent control box. The upper hook is mostly double U-shaped or ring-type, equipped with an overload protection device, and is driven by a motor. It offers fast lifting and high precision, is suitable for jacks over 3 tons, and is ideal for heavy loads and high-frequency operations.

[0024] This invention adopts an integrated design of gantry frame, hoist, and pallet, eliminating the need for large equipment and requiring only 2-3 people to operate. The time required to replace a single set of pads is reduced by over 60% compared to traditional methods, making it suitable for continuous construction. The pallet utilizes hoists on four sides for precise chain control, preventing support misalignment and the "three-legged" problem. The adjustable frame height adapts to piers ranging from 1.2 to 3.5 meters, is compatible with both light and heavy jacks, and is suitable for confined spaces. The core components of the device are reusable, reducing equipment and labor costs by 60%-70%, simplifying maintenance, and offering excellent economic benefits.

[0025] The following is a method for replacing the lower pad of a convenient walking jack with a liftable support according to the present invention (e.g.) Figure 8 As shown, from left to right, these are the four states during operation: 1. Initial Preparation: Assemble the gantry frame 5 (including the hoist 6) and the support plate 7 as required, connecting the lower hook 62 of the hoist 6 to the hook ring 71 of the support plate 7. The support plate 7 supports the walking jack 3, and a pad block 4 is placed under the support plate 7. The gantry frame 5 stands stably on the pier 2 (e.g., Figure 8 (The first state in the middle).

[0026] 2. Bridge jacking: The vertical pushing mechanism of the walking jack 3 jacks the steel box girder 1, and then the translational pushing mechanism of the walking jack 3 pushes the walking jack 3, causing the steel box girder 1 to move horizontally (e.g., ...). Figure 8 In the second state, the jack has an upward arrow.

[0027] 3. Replace the shims: After the translation is completed, control the vertical pushing mechanism of the walking jack 3 to retract, and the walking jack 3 will separate from the steel box girder 1. Figure 8 In the third state, the jack has a downward arrow; start the hoist 6 to retract the chain, and the pallet 7 will drive the walking jack 3 to rise until there is enough space between the bottom of the jack 3 and the steel box girder 1 to place the additional pad 41. Figure 8 In the third state, place the new pad block 41 on the far left.

[0028] In this step, the hoists 6 on the front and rear sides of the pallet 7 can return the pallet 7 to its initial position before translation by controlling the chain length.

[0029] 4. Lowering and Resetting: Operate hoist 6 to release the chain, and pallet 7 will drive walking jack 3 to slowly lower the crane. Figure 8 (In the fourth state), the bottom of the walking jack 3 is placed smoothly on the new pad, completing the pad replacement.

[0030] Repeat the above operations until the translation of the entire steel box girder 1 is completed.

[0031] Through the above steps, the replacement of the pad blocks is highly efficient, with each step closely connected. It does not rely on large equipment, and the replacement time for a single set of pad blocks is reduced by more than 60% compared to the traditional method. It can also be coordinated with the jacking operation to avoid process interruption. The operation process is safe and reliable, with the support standing stably on the pier, the hoist hook having a locking mechanism, and personnel not needing to enter the danger zone. The force transition is smooth. Furthermore, the equipment is reusable, and only 2-3 people are needed, significantly reducing costs.

[0032] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A portable walking type jack lower pad replacement liftable support, characterized in that, The utility model relates to a kind of steel box girder lifting device, including: Walking jack (3) for supporting steel box girder (1), the walking jack (3) includes vertical pushing mechanism and translation pushing mechanism; Supporting plate (7), the walking jack (3) is placed on the supporting plate (7), cushion block (4) is arranged below the supporting plate (7), and lifting hook ring (71) is arranged on the supporting plate (7); Portal support (5) is arranged outside the walking jack (3), and the portal support (5) includes top frame (55), lower support sleeve (52) and upper support sleeve (54), four upper support sleeves (54) are arranged below four corners of the top frame (55), the lower support sleeve (52) is four and bottom is provided with bottom plate (51), the lower support sleeve (52) and upper support sleeve (54) are all hollow tubular structure and are provided with multiple positioning holes, the lower support sleeve (52) is sleeved in upper support sleeve (54) and is fixed by fixed bolt (53) inserted into positioning hole; Hoist (6) is fixed on the top frame (55) of the portal support (5), and the hoist (6) is provided with hoist upper hook (61), chain and hoist lower lifting hook (62), the hoist upper hook (61) cooperates with hoist hook hole (56) of top frame (55), one end of the chain is fixed on pier (2), and the other end is connected with the lifting hook ring (71) of supporting plate (7) by hoist lower lifting hook (62), and supporting plate (7) and walking jack (3) are lifted by winding and unwinding chain.

2. The portable and walkable jack lower pad replacement liftable support according to claim 1, wherein, The lifting hook ring (71) of the supporting plate (7) is arranged on the edge of the upper surface of the supporting plate (7).

3. The portable and walkable jack lower pad replacement liftable support according to claim 1, wherein, The top frame (55) is a rectangular frame structure, and the hoist hook hole (56) is arranged on the four edge frames of the top frame (55).

4. The portable foot-operated jack cribbing replacement liftable support of claim 1, wherein, The hoist (6) is a manual or electric hoist.

5. The portable foot-operated jack cribbing replacement liftable support of claim 1, wherein, Two hoists (6) are arranged on the left and right side edge frames of the top frame (55) respectively and are symmetrically distributed along the length direction of the edge frame, and one hoist (6) is arranged on the front and rear side edge frames of the top frame (55) respectively and is located at the midpoint position of the edge frame.

6. The portable foot-operated jack cribbing replacement liftable support of claim 1, wherein, The hoists (6) on the left and right sides of the supporting plate (7) can make the supporting plate (7) return to the initial position before translation by controlling the length of the chain.

7. The portable and walkable jack pad replacement lift stand of claim 1, wherein, The height adjustment range of the portal support (5) is 1.2-3.5 m.

8. A method of replacing a portable lifting jack with a portable walking jack according to any one of claims 1-7, characterized in that, The utility model includes the following steps: S1: assemble portal support (5), hoist (6) and supporting plate (7), connect hoist lower lifting hook (62) with lifting hook ring (71) of supporting plate (7), supporting plate (7) carries walking jack (3) and places cushion block (4), and portal support (5) is fixed on pier (2); S2: push steel box girder (1) by vertical pushing mechanism of walking jack (3), and then drive steel box girder (1) to translate by translation pushing mechanism; S3: retract the vertical pushing mechanism to make the jack separate from the steel box girder (1), start hoist (6) to wind chain and lift supporting plate (7), place new cushion block (41) after adjusting supporting plate (7) to the initial position. S4: the chain of the hoist pulley (6) is released, the support plate (7) drives the jack to fall on the new pad, and the replacement is completed.

9. The method of claim 8, wherein, In step S3, the hoist pulley (6) on both sides of the support plate (7) can control the length of the chain, so that the support plate (7) can return to the initial position before translation.

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