A prefabricated assembly type cover beam translation installation device and installation method under an existing bridge

Abstract

The application provides a prefabricated and assembled cover beam translation installation device and method under an existing bridge, which comprises a bearing platform, prefabricated columns, a plurality of steel pipe supports, a steel structure distribution beam, a translation slide, a translation counterforce back, a translation hydraulic jack, a beam falling jack and a PLC synchronous control unit. The prefabricated columns are hoisted on the bearing platform, the steel pipe supports are vertically arranged on the bearing platform, the steel structure distribution beam is arranged at the upper end of the steel pipe support, and the translation support is formed by the steel structure distribution beam and the steel pipe support. The translation slide is installed on the top surface of the steel structure distribution beam, and the translation slide is internally provided with a steel structure slide foot and a beam bottom distribution beam. The translation counterforce back and the translation hydraulic jack are installed on one side of the translation slide. The beam falling hydraulic jack and the beam falling following jack are installed at the bottom of the prefabricated cover beam. The translation hydraulic jack, the beam falling hydraulic jack and the beam falling following jack are controlled by the PLC synchronous control unit, so that the translation and beam falling of the prefabricated cover beam are realized.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a device and method for the translation and installation of prefabricated assembled cap beams under existing bridges. Background Technology

[0002] In recent years, prefabricated assembly construction methods have been widely used in the field of building engineering, especially in bridge engineering, where the prefabrication and assembly rate of components such as columns, cap beams, concrete box girders, and steel box girders above the pier cap has reached a maximum of 82%. Prefabricated assembly construction has advantages such as high efficiency, safety, no pollution, high quality, low cost, and shortened construction period.

[0003] In current technological fields, the installation of prefabricated components generally relies on hoisting equipment. During hoisting operations, sufficient space above the intended location of the hoisted object must be ensured. However, in existing bridge renovation projects, the superstructure is preserved and reused through jacking technology, while the substructure is rebuilt or renovated to restore the bridge's function. Because the construction space for the substructure is limited by the projected area of ​​the superstructure, traditional hoisting methods are insufficient if prefabricated assembly is used for substructure components such as piers and cap beams. Therefore, in existing bridge renovation projects, especially in scenarios with limited clearance, the reconstruction of the substructure must abandon prefabricated assembly methods, which negatively impacts project construction time and costs. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a device and method for the translational installation of prefabricated prefabricated cap beams under existing bridges, thereby solving the problem of how to achieve precise positioning and installation of prefabricated prefabricated cap beams under the constraints of existing bridge space.

[0005] This invention provides a precast prefabricated cap beam translation and installation device under an existing bridge. The existing bridge includes a pier cap and precast columns fixed to the pier cap. The precast precast columns are fixed to the pier cap. The precast prefabricated cap beam translation and installation device under the existing bridge includes: several steel pipe supports, which are vertically arranged on the pier cap and fixedly connected to the pier cap at their lower ends. The steel pipe supports are connected by channel steel. A steel structure distribution beam is arranged on the upper end of the steel pipe supports. A translation slide is installed on the top surface of the steel structure distribution beam and a steel structure is installed inside it. The structure includes a sliding foot and a beam bottom distribution beam, a translation reaction backing, a translation reaction backing connected to one side of the translation slide, a translation hydraulic jack, a translation hydraulic jack positioned between the translation reaction backing and the beam bottom distribution beam, a beam lowering jack, which includes a beam lowering hydraulic jack and a beam lowering follower jack, both of which are hoisted at the bottom of the precast cap beam, and a PLC synchronous control unit, which is connected to the translation hydraulic jack, the beam lowering hydraulic jack, and the beam lowering follower jack respectively.

[0006] The existing bridge prefabricated cap beam translation installation device provided by the present invention may also have the following features: the lower end of the steel pipe support is connected to the abutment by means of rebar installation, and a gap is provided between the support and the abutment. Grout is injected into the gap, and the two ends of the channel steel are respectively connected between different steel pipe supports to connect and fix the steel pipe supports.

[0007] The existing bridge prefabricated cap beam translation installation device provided by the present invention may also have the following features: the top surface elevation of the steel structure distribution beam is lower than the design bottom elevation of the prefabricated cap beam, the top surface of the steel structure distribution beam is provided with a leveling layer, and the translation slide is installed on the top surface of the leveling layer.

[0008] The existing bridge prefabricated cap beam translation installation device provided by the present invention may also have the following features: the number of steel structure distribution beams is three, and two sets of steel pipe supports are arranged below each steel structure distribution beam. The steel structure distribution beams and steel pipe supports are connected by full welding to form a translation bracket. A translation slide is installed on the top surface of each steel structure distribution beam.

[0009] The existing bridge prefabricated cap beam translation installation device provided by the present invention may also have the following features: the translation slide adopts a channel steel structure, the bottom of the steel structure sliding foot is embedded in the channel steel structure, and a PTFE plate is inserted in the channel steel structure. Two steel structure sliding feet are provided in each translation slide. The beam bottom distribution beam is installed on the upper part of the steel structure sliding foot, and limit blocks are provided at both ends of the beam bottom distribution beam.

[0010] The existing bridge prefabricated cap beam translation and installation device provided by the present invention may also have the following features: the beam-dropping hydraulic jack and the beam-dropping follow-up jack are hoisted at the bottom of the prefabricated cap beam and are fixedly connected to the prefabricated cap beam by means of pre-embedded sleeves.

[0011] The existing bridge prefabricated cap beam translation and installation device provided by the present invention may also have the following features: there are four hydraulic jacks for lowering the beam and four follow-up jacks for lowering the beam, which are symmetrically arranged at the bottom of the prefabricated cap beam. Each hydraulic jack for lowering the beam and each follow-up jack for lowering the beam are equipped with a set of steel pipe supports for lowering the beam.

[0012] The existing bridge prefabricated cap beam translation and installation device provided by the present invention may also have the following features: the beam lowering hydraulic jack is equipped with a full-stroke self-locking thread, and the beam lowering following jack is equipped with a mechanical screw, which is driven by a hydraulic motor to automatically follow and achieve mechanical self-locking.

[0013] The existing bridge prefabricated cap beam translation installation device provided by the present invention may also have the following features: stiffening plates are welded on both sides of the steel structure sliding foot on the bottom distribution beam, and the translation reaction back is welded to the stiffening plates through square tubes.

[0014] In addition, the present invention also provides an installation method based on the above-mentioned prefabricated assembled cap beam translation installation device under existing bridges, including the following steps: Step 1: First, hoist the precast columns. After hoisting, install the steel pipe supports, connect and fix the steel pipe supports to the foundation, and install channel steel between the steel pipe supports for connection and reinforcement. Step 2: Install the steel structure distribution beam on the top surface of the steel pipe support by full welding to form a translation frame. After the frame is installed, level the top surface of the steel structure distribution beam. Step 3: Install a sliding track on the top surface of the leveling layer of the steel structure distribution beam, and install steel structure sliding feet inside the sliding track; Step 4: Install the bottom distribution beam on the top of the steel structure sliding foot, and at the same time install the limiting blocks at both ends of the bottom distribution beam. When hoisting the precast cap beam, it will be locked between the two limiting blocks. Step 5: Install and debug the PLC synchronous control unit, and move the precast cover beam to the predetermined position; Step Six: Verify the alignment accuracy of the precast columns and precast cap beams. If there is a deviation, use the correction unit for fine-tuning. Step 7: Install hydraulic jacks and follow-up jacks for lowering the precast cap beam at the bottom; Step 8: Install and debug the PLC synchronous control unit, lower the precast cap beam to the designed position, and complete the precise docking of the precast cap beam and the precast column.

[0015] The beneficial effects of this invention are as follows: The existing precast bridge cap beam translation and installation device of the present invention includes a pier, precast columns, several steel pipe supports, a steel structure distribution beam, a translation slide, a translation reaction backing, translation hydraulic jacks, beam lowering jacks, and a PLC synchronous control unit. First, the precast columns are hoisted onto the pier. Then, the steel pipe supports are vertically installed on the pier, and a steel structure distribution beam is installed at the upper end of the steel pipe supports, forming a translation support through the steel structure distribution beam and the steel pipe supports. The translation slide is installed on the top surface of the steel structure distribution beam, and its interior contains steel structure sliding feet and a beam bottom distribution beam. Then, a translation reaction backing and a translation hydraulic jack are installed on one side of the translation slide. Before lowering the precast cap beam, a beam lowering hydraulic jack and a beam lowering follow-up jack are installed at its bottom. Furthermore, the translation hydraulic jack, beam lowering hydraulic jack, and beam lowering follow-up jack are connected and controlled by the PLC synchronous control unit to realize the translation and lowering of the precast cap beam.

[0016] The installation device described in this application effectively overcomes the challenges of positioning and installing prefabricated components in existing bridge reconstruction projects, especially in scenarios with limited clearance. Using factory-prefabricated components for substructure reconstruction in clearance-constrained environments shortens the construction period by approximately 40%, significantly improving construction efficiency while substantially reducing the time spent working at heights and simultaneously lowering safety risks. The prefabrication process reduces concrete usage by up to 35% compared to traditional cast-in-place techniques, effectively controlling dust and noise pollution levels and fully implementing green building principles.

[0017] In addition, a PLC synchronous control unit is used to achieve millimeter-level precision control, with elevation deviation ≤ ±2mm and lateral displacement deviation ≤ ±1mm, perfectly adapting to the millimeter-level docking standard for prefabricated component installation.

[0018] Furthermore, in this application, several steel pipe supports are connected by channel steel as connectors, and adjacent steel pipe supports are connected by channel steel, so that several steel pipe supports are connected by channel steel to form a three-dimensional lattice stable system. Combined with the PLC synchronous control unit, the risk of structural instability is reduced by 70%, and a dual safety protection mechanism is constructed.

[0019] In addition, the translation slide in this application adopts a channel steel structure as a guide rail device, and utilizes the precise guiding function of the flange to achieve a deviation rate of ≤0.5‰ for the translation trajectory of the sliding foot, thus ensuring the vector control accuracy of the translation process.

[0020] In addition, the hydraulic jack for beam lowering in this application is equipped with a full-stroke self-locking thread, and the follower jack for beam lowering is equipped with a mechanical screw. The mechanical screw is driven by a hydraulic motor to automatically follow and achieve mechanical self-locking. By using the above-mentioned dual-machine control mode of hydraulic jack and follower jack, the follower jack is configured during the beam lowering stage to completely eliminate safety hazards such as power failure and hydraulic leakage.

[0021] In addition, in this application, the translation and beam lowering support system adopts a modular steel splicing structure, and the standardized disassembly and assembly process enables the component reuse rate to reach 92%, reducing the overall construction cost by 25%.

[0022] Furthermore, this application also provides an installation method for the aforementioned precast cap beam installation device. This method, employing precast cap beam translation technology, effectively overcomes the challenge of precisely positioning and installing precast cap beams when space constraints exist within existing bridge structures. This installation method allows for the translation of the precast cap beam to a predetermined position even when space on the existing bridge is limited. Then, using building-mounted lowering technology, the precast cap beam is precisely lowered to the designed position and its connection is completed. Ultimately, this achieves seamless integration and performance upgrades for the existing bridge system. Attached Figure Description

[0023] Figure 1This is a cross-sectional schematic diagram of the prefabricated assembled cap beam translation and installation device under the existing bridge in this embodiment. Figure 2 This is a longitudinal section schematic diagram of the prefabricated assembled cap beam translation and installation device under the existing bridge in this embodiment; Figure 3 This is an elevation view of the prefabricated cap beam translation structure in this embodiment; Figure 4 This is a detailed structural diagram of the beam bottom distribution beam in this embodiment. Detailed Implementation

[0024] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0025] like Figures 1-4 As shown, the existing bridge prefabricated cap beam translation installation device in this embodiment includes a pier 10, prefabricated columns 20, several steel pipe supports 30, steel structure distribution beams 40, translation slides 50, translation reaction back 60, translation hydraulic jacks 70, beam lowering hydraulic jacks 81, beam lowering following jacks 82, and a PLC synchronous control unit (not shown in the figure).

[0026] The precast column 20 is installed above the pier cap 10 by hoisting. The upper end of the precast column 20 is reserved with a dowel bar 21, which is precisely aligned with the precast cap beam 100.

[0027] After the precast columns 20 are hoisted, several steel pipe supports 30 are vertically installed on the foundation 10. The bottom of the supports is connected and fixed to the newly built foundation 20 by high-strength bolts 31, and an 8cm gap is reserved between the bottom surface and the top surface of the foundation 20. This gap is filled with grout. The verticality of the steel pipe supports 30 is controlled within 6%.

[0028] In addition, the steel pipe supports 30 are connected and reinforced by channel steel 32 as a connector. The two ends of the channel steel 32 are used to connect the two different steel pipe supports 30, thereby connecting the steel pipe supports 30 and forming a stable structure between them.

[0029] The steel structure distribution beam 40 is installed on the upper end of the steel pipe support 30. There are three steel structure distribution beams 40, each paired with two sets of steel pipe supports 30. Therefore, in this embodiment, there are six sets of steel pipe supports 30 used for translation in conjunction with the steel structure distribution beams 30. In other embodiments, the number of steel pipe supports 30 can be adjusted according to the actual engineering conditions.

[0030] The steel structure distribution beam 40 is fully welded to the top of the steel pipe support 30. The steel structure distribution beam 40 and the steel pipe support 30 form a translational support. The full welding method allows the translational support to withstand both bending moment and a certain amount of tensile force.

[0031] The steel structure distribution beam 40 is constructed by fully welding 20mm thick steel plates together for the web and stiffening plates, with a height of 800mm and a width of 420mm. Furthermore, the top surface elevation of this steel structure distribution beam 30 is 5cm lower than the design bottom elevation of the precast cap beam 100, facilitating elevation control during the lowering of the precast cap beam 100.

[0032] In addition, the three steel structure distribution beams 40 need to be at the same elevation. To prevent uneven deformation of the precast cap beam 100 caused by sudden changes in elevation during the translation process, the top surface of the steel structure distribution beams 40 is precisely leveled. C50 self-leveling grouting material is used for precise leveling to form a leveling layer with a thickness of about 20~40mm.

[0033] The translation slide 50 is installed on the top surface of the leveling layer of the steel structure distribution beam 40, and each steel structure distribution beam 40 is equipped with a corresponding translation slide 50.

[0034] The translation slide 50 is made of 36C channel steel. The outer flange of the channel steel is welded to the steel structure distribution beam 40. The movement direction of the steel structure slide foot is restricted by the channel steel flange, thereby ensuring that the precast cap beam 100 does not shift during translation.

[0035] The translation slide 50 is equipped with steel structure sliding feet 51 and beam bottom distribution beams 52. To minimize sliding friction between the steel structure sliding feet 51 and the translation slide 50, the bottom of the steel structure sliding feet 51 is embedded in the steel groove of the translation slide 50, and a PTFE plate is also inserted into the steel groove. The PTFE plate and the channel steel are in direct contact, and grease is applied to the surface of the translation slide 50 during translation to enhance lubrication. In this embodiment, the precast cap beam 100 requires six steel structure sliding feet 51 for translation, arranged in three rows, with two sliding feet in each translation slide 50.

[0036] like Figure 4 As shown, the bottom distribution beam 52 includes a stiffening plate 53, an H-beam 54, and a steel plate 55. To ensure the linkage performance between the steel structure sliding feet 51, a bottom distribution beam 52 is installed on the top of the two steel structure sliding feet 51 on each translation slide 50. The bottom distribution beam 52 also serves to bear the self-weight load of the precast cap beam 1. In this embodiment, the bottom distribution beam 52 adopts HW294 steel. Made of 302 steel 54, five 10mm thick stiffening plates 53 are welded to each side of the corresponding steel structure sliding foot 51. Steel plates 55 are installed at the force application points of the translation hydraulic jack 70. At the same time, two limiting blocks are welded to both ends of the top of the beam 52 at the bottom of the beam. The clear distance between the limiting blocks is 2150mm. When the precast cap beam 100 is hoisted, it is inserted between the two limiting blocks, and the gap is tightened by square timber.

[0037] The translational reaction force backrest 60 and the translational slide rail 50 are connected as a whole by high-strength bolts. In this embodiment, the number of translational reaction force backrests 60 corresponds to the number of translational slide rails 50, and a total of 3 sets are provided. Furthermore, in this embodiment, the translational reaction force backrest 60 is composed of 300... 300 It is made of 12mm square tubes and stiffening plates welded together. The high-strength bolts are M20-8.8 grade bearing type. After forming a whole, it uses the self-weight of the precast cap beam 100 to achieve self-balancing force, so that the force transmission of the whole translation structure is clear and the structure is stable.

[0038] The translation hydraulic jack 70 is installed between the translation reaction back 60 and the beam bottom distribution beam 52 to provide jacking force for the translation of the precast cap beam 100.

[0039] The PLC synchronous control unit is connected to the translation hydraulic jack 70, including a hydraulic power pump station, a high-precision displacement sensing module, and an intelligent translation control unit, and achieves coordinated operation through bus communication. Then, the hydraulic synchronous translation operation of the precast cap beam 100 can be started.

[0040] The above structure forms the translation structure for the precast cap beam 100, and its translation mechanism is as follows: During the translation phase, the PLC synchronous control unit controls the translation hydraulic jack 70 to pressurize and push the precast cover beam 100. During this period, the displacement sensor transmits displacement monitoring data back in real time. The system advances gradually in a standard stroke of 70cm. After a single stroke is completed, the PLC synchronous control unit controls the translation hydraulic jack 70 to complete the depressurization and retraction cylinder action. Then, steel pads are precisely inserted between the translation hydraulic jack 70 and the bearing surface of the translation reaction back 60, and then the next stroke translation program is started until the complete translation is completed.

[0041] After the precast cap beam 100 is moved into place, a comprehensive inspection is conducted to verify the alignment accuracy between the precast reinforcing bars 21 on the precast column 20 and the bottom sleeve of the precast cap beam 100. If any deviation is found, a two-dimensional adjustable hydraulic correction system must be immediately activated for fine-tuning to ensure that the bottom sleeve of the precast cap beam 100 and the reinforcing bars 21 are in a three-dimensional coordinate alignment state. Only after the axial deviation value is confirmed to meet the specification requirements through re-measurement can the multi-support synchronous graded beam lowering operation be carried out, ultimately achieving millimeter-level precise docking of the structural system of the precast cap beam 100 and the precast column 20.

[0042] Hydraulic jacks 81 and 82 for lowering beams are installed at corresponding positions on the bottom of the precast cap beam 100. The hydraulic jacks 81 and 82 for lowering beams are fixedly connected to the bottom of the precast cap beam 100 through pre-embedded sleeves.

[0043] In this embodiment, based on the self-weight of the precast cap beam 100, four hydraulic jacks 81 and four follow-up jacks 82 are installed at the bottom of the precast cap beam 100. The safety factor is 5 times. During the prefabrication process, bolt sleeves are pre-installed at corresponding positions at the bottom of the precast cap beam 100. The jacks are all hoisted at the bottom of the precast cap beam 100 and secured by the pre-embedded sleeves. A 5cm gap is left between the steel plate of the jack and the bottom of the precast cap beam 100, and this gap is filled with C50 self-leveling grout for leveling.

[0044] In addition, each beam-lowering hydraulic jack and beam-lowering follow-up jack is also equipped with a set of steel pipe supports for beam lowering.

[0045] The beam lowering hydraulic jack 81 is equipped with a full-stroke self-locking thread. This full-stroke self-locking thread solves the problem of tightening the self-locking nut when replacing the steel pipe support for beam lowering, and enables the beam lowering hydraulic jack 81 to lock itself.

[0046] Furthermore, the balance protection load-equalizing valve inside the beam-lowering hydraulic jack 81 is a leak-free cone valve structure. This leak-free cone valve structure achieves its four main functions, namely: The load pressure of the balanced beam-lowering hydraulic jack 81 is balanced so that the beam-lowering hydraulic jack 81 does not lose pressure and slide down when it is lowered under load, and the workpiece will not fall even if the oil pipe ruptures. To prevent the hydraulic jack 81 from overloading, when the pressure inside the hydraulic jack 81 exceeds the set pressure, the load equalization valve can automatically open to relieve the excessive oil pressure and balance the load on the hydraulic jack 81. In addition, the load equalization valve is a plate-type connection and can be directly installed on the hydraulic jack 81, which can minimize the trouble caused by external pipelines. The oil inlet speed regulation function avoids the significant impact on the load caused by excessive hydraulic fluctuations during synchronous descent. When multiple hydraulic jacks 81 with balance valves support a heavy load simultaneously, the hydraulic jack 81 with the larger load will open first when synchronous descent is required (heavy load first opening function), which truly ensures the reliable synchronous descent function of the system.

[0047] In addition, the beam-lowering jack 82 is equipped with a mechanical screw, which is automatically driven by a hydraulic motor to follow the beam. This mechanical screw bears the force (rigid force), ensuring reliable and risk-free beam-lowering jack 82. When the beam is lowered by the hydraulic jack 81, the beam-lowering jack 82 can follow and protect the beam in real time. In case of an accident, it can achieve mechanical self-locking without relying on the hydraulic system.

[0048] The beam-lowering follow-up jack (82mm) is a mechanical jack capable of actively applying a pre-jacking force of tens of tons (similar to the principle of a hydraulic tensioner, which generates pre-tightening force before tightening the screws). This eliminates deformation and installation gaps in the steel pipe supports. It fundamentally and thoroughly resolves hazards such as power outages, internal leakage of the hydraulic jack, damage to hydraulic seals, and malfunctions in computer controls or electronic components, achieving practical protection.

[0049] By using the beam-lowering hydraulic jack 81 and the beam-lowering follower jack 82 in combination, both the beam-lowering hydraulic jack 81 and the beam-lowering follower jack 82 can achieve self-locking when the steel pipe support is replaced and subjected to force alone. This prevents power outages, internal leakage of the hydraulic jack, damage to the hydraulic seal, and failure of computer control or electronic components, thereby improving the safety and stability of the entire beam-lowering device.

[0050] The PLC synchronous control unit is also connected to the beam-lowering hydraulic jack 81 and the beam-lowering follower jack 82 to control the beam-lowering hydraulic jack 81 and the beam-lowering follower jack 82 to perform beam-lowering work.

[0051] The working mechanism of the precast cap beam 100 is as follows: A 22cm gap is left between the beam-lowering hydraulic jack 82 and the steel pipe support, which will be left untreated for now, as space for debugging the beam-lowering hydraulic jack 82. Connect the hydraulic pipe of the beam-lowering hydraulic jack 82 to the control system, turn on the pump station, and test the beam-lowering hydraulic jack 82 to observe whether it can extend and retract freely. After confirming that the beam-lowering hydraulic jack 82 is fault-free, fill the previous 22cm gap with the support fully retracted. The beam-lowering hydraulic jack 81 lifts upward by 1cm, and the beam-lowering hydraulic jack 82 automatically extends downward by 1cm. Tighten the pressure-holding ring of the beam-lowering hydraulic jack 81 downward to the bottom, and the beam is fully lowered. Hydraulic jack 81 retracts its cylinder, transferring the upper load from the lowering hydraulic jack 81 to the lowering follow-up jack 82. The bottom of the lowering hydraulic jack 81 detaches from the steel pipe support. The steel pipe support at the bottom of the lowering hydraulic jack 81 is then pulled out 20cm. Next, the lowering hydraulic jack 81 is extended another 21cm, lifting the precast cap beam 100 upwards by 1cm. The force is then transferred back to the lowering hydraulic jack 81, at which point the bottom of the lowering follow-up jack 82 detaches from the steel pipe support. The steel pipe support at the bottom of the lowering follow-up jack 82 is pulled out 20cm, and the lowering follow-up jack 82 is fully retracted. The lowering hydraulic jack 81 is retracted 20cm via the PLC synchronous control unit, causing the precast cap beam 100 to fall 20cm synchronously. The lowering follow-up jack 82 is tightened downwards to ensure close contact with the steel pipe support, completing one lowering stroke. The above steps are repeated until the entire lowering operation of the precast cap beam 100 is completed.

[0052] In addition, this embodiment also provides an installation method for the prefabricated assembled cap beam translation installation device under the existing bridge, which mainly includes the following steps: Step 1: First, hoist the precast column 20 and pre-install reinforcing bars 21 on the precast column 20. After hoisting, install the steel pipe support 30 and connect and fix it to the new foundation 10 with high-strength bolts 31. Leave an 8cm space between the bottom surface of the steel pipe support 30 and the top surface of the new foundation 10, and fill the space with grout. In addition, channel steel 32 is used as connecting rods between each steel pipe support 30 for connection and reinforcement to form a stable grid structure. Step 2: Install the steel structure distribution beam 40 on the top surface of the steel pipe support 30. The steel structure distribution beam 40 and the steel pipe support 30 are connected by full welding to form a translation frame. After installation, the top surface of the steel structure distribution beam 40 is accurately leveled. Step 3: Install the translation slide 50 on the top surface of the leveling layer of the steel structure distribution beam 40. The translation slide 50 is made of 36C channel steel, and the outer flange of the channel steel is welded to the steel structure distribution beam 40. Install the steel structure sliding foot 51 in the channel steel, embed the bottom of the steel structure sliding foot 51 into the steel channel, and insert a PTFE plate into the steel channel. Apply grease to the surface of the translation slide 50 to enhance lubrication during translation. Step 4: Install a bottom distribution beam 52 on the top of every two steel structure sliding feet 51, and weld two limiting blocks to the top end of the bottom distribution beam 52. When the precast cap beam 100 is hoisted, it is inserted between the two limiting blocks, and the gap is tightened by square timber. Step 5: Install and debug the PLC synchronous control unit, and move the precast cover beam 100 to the predetermined position; Step 6: Fully verify the alignment accuracy between the pre-reserved reinforcing bars 21 on the precast column 20 and the bottom sleeve of the precast cap beam 100. If there is a deviation, the two-dimensional adjustable hydraulic correction system must be activated immediately to make fine adjustments to ensure that the sleeve and the pre-reserved reinforcing bars 21 on the precast column 20 form a three-dimensional coordinate matching state. Step 7: Install the beam-dropping hydraulic jack 81 and beam-dropping follow-up jack 82 at the bottom of the precast cap beam 100. The jacks are all hoisted at the bottom of the precast cap beam 100 and fixed by the pre-embedded sleeve. A 5cm gap is reserved between the jack ceiling steel plate and the bottom of the precast cap beam 100. The gap is filled with C50 self-leveling grout to level it. Step 8: Install and debug the PLC synchronous control unit, lower the precast cap beam 100 to the designed position, and complete the precise docking of the precast cap beam 100 and the precast column 20.

[0053] The existing precast bridge cap beam translation and installation device described in the above embodiment includes a pier, precast columns, several steel pipe supports, a steel structure distribution beam, a translation slide, a translation reaction backing, translation hydraulic jacks, beam lowering jacks, and a PLC synchronous control unit. First, the precast columns are hoisted onto the pier. Then, the steel pipe supports are vertically installed on the pier, with a steel structure distribution beam installed at the upper end of the steel pipe supports, forming a translation support structure. The translation slide is installed on the top surface of the steel structure distribution beam, and contains steel structure sliding feet and a beam bottom distribution beam. Then, a translation reaction backing and a translation hydraulic jack are installed on one side of the translation slide. Before lowering the precast cap beam, beam lowering hydraulic jacks and beam lowering follow-up jacks are installed at its bottom. Furthermore, the PLC synchronous control unit connects and controls the translation hydraulic jacks, beam lowering hydraulic jacks, and beam lowering follow-up jacks to achieve the translation and lowering of the precast cap beam.

[0054] The installation device described in this application effectively overcomes the challenges of positioning and installing prefabricated components in existing bridge reconstruction projects, especially in scenarios with limited clearance. Using factory-prefabricated components for substructure reconstruction in clearance-constrained environments shortens the construction period by approximately 40%, significantly improving construction efficiency while substantially reducing the time spent working at heights and simultaneously lowering safety risks. The prefabrication process reduces concrete usage by up to 35% compared to traditional cast-in-place techniques, effectively controlling dust and noise pollution levels and fully implementing green building principles.

[0055] In addition, a PLC synchronous control unit is used to achieve millimeter-level precision control, with elevation deviation ≤ ±2mm and lateral displacement deviation ≤ ±1mm, perfectly matching the millimeter-level docking standard for prefabricated component installation.

[0056] Furthermore, in this application, several steel pipe supports are connected by channel steel as connectors, and adjacent steel pipe supports are connected by channel steel, so that several steel pipe supports are connected by channel steel to form a three-dimensional lattice stable system. Combined with the PLC synchronous control unit, the risk of structural instability is reduced by 70%, and a dual safety protection mechanism is constructed.

[0057] In addition, the translation slide in this application adopts a channel steel structure as a guide rail device, and utilizes the precise guiding function of the flange to achieve a deviation rate of ≤0.5‰ for the translation trajectory of the sliding foot, thus ensuring the vector control accuracy of the translation process.

[0058] In addition, the hydraulic jack for beam lowering in this application is equipped with a full-stroke self-locking thread, and the follower jack for beam lowering is equipped with a mechanical screw. The mechanical screw is driven by a hydraulic motor to automatically follow and achieve mechanical self-locking. By using the above-mentioned dual-machine control mode of hydraulic jack and follower jack, the follower jack is configured during the beam lowering stage to completely eliminate safety hazards such as power failure and hydraulic leakage.

[0059] In addition, in this application, the translation and beam lowering support system adopts a modular steel splicing structure, and the standardized disassembly and assembly process enables the component reuse rate to reach 92%, reducing the overall construction cost by 25%.

[0060] Furthermore, this application also provides an installation method for the aforementioned precast cap beam installation device. This method, employing precast cap beam translation technology, effectively overcomes the challenge of precisely positioning and installing precast cap beams when space constraints exist within existing bridge structures. This installation method allows for the translation of the precast cap beam to a predetermined position even when space on the existing bridge is limited. Then, using building-mounted lowering technology, the precast cap beam is precisely lowered to the designed position and its connection is completed. Ultimately, this achieves seamless integration and performance upgrades for the existing bridge system.

[0061] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A device for the translational installation of precast assembled cap beams under an existing bridge, the existing bridge including a pier cap and precast columns, wherein the precast columns are fixed on the pier cap, characterized in that, include: Several steel pipe supports are vertically mounted on the bearing platform, with their lower ends fixedly connected to the platform. The steel pipe supports are connected to each other via channel steel. A steel structure distribution beam is provided, which is located at the upper end of the steel pipe support. A sliding track is installed on the top surface of the steel structure distribution beam, and a steel structure sliding foot and a beam bottom distribution beam are installed inside it. The translational reaction force backing is connected to one side of the translational slide. A translational hydraulic jack is positioned between the translational reaction force backing and the beam bottom distribution beam. The beam-lowering jacks include hydraulic beam-lowering jacks and follow-up beam-lowering jacks, both of which are installed at the bottom of the precast cap beam. The PLC synchronous control unit is connected to the translation hydraulic jack, the beam lowering hydraulic jack, and the beam lowering follower jack.

2. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The lower end of the steel pipe support is connected to the foundation by rebar anchoring, and a gap is provided between the support and the foundation, which is filled with grout. The two ends of the channel steel are respectively connected between different steel pipe supports to connect and fix the steel pipe supports.

3. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The top surface elevation of the steel structure distribution beam is lower than the design bottom elevation of the precast cap beam. The top surface of the steel structure distribution beam is provided with a leveling layer, and the translation slide is installed on the top surface of the leveling layer.

4. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The steel structure distribution beam consists of three beams, and each beam is supported by two sets of steel pipe supports. The steel structure distribution beams and the steel pipe supports are connected by full welding to form a translational support. Each of the steel structure distribution beams has a translation slide installed on its top surface.

5. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The translation slide is made of channel steel, and the bottom of the steel structure sliding foot is embedded in the channel steel structure, with a PTFE plate inserted inside the channel steel structure. Each of the aforementioned translation slides is equipped with two steel structure sliding feet, and the beam bottom distribution beam is installed on the upper part of the steel structure sliding feet. Limiting blocks are provided at both ends of the bottom distribution beam.

6. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The beam-dropping hydraulic jack and the beam-dropping follow-up jack are hoisted at the bottom of the precast cap beam and are fixedly connected to the precast cap beam by means of a pre-embedded sleeve.

7. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 5, characterized in that: The hydraulic jacks for lowering the beam and the follow-up jacks for lowering the beam are each in a set of four, and are symmetrically arranged at the bottom of the precast cap beam. Each of the aforementioned beam-lowering hydraulic jacks and the beam-lowering follow-up jacks is equipped with a set of steel pipe supports for beam lowering.

8. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: The hydraulic jack for lowering the beam is equipped with a full-stroke self-locking thread. The beam-lowering jack is equipped with a mechanical screw, which is driven by a hydraulic motor to automatically follow the beam and achieve mechanical self-locking.

9. The prefabricated assembled cap beam translation and installation device under existing bridges according to claim 1, characterized in that: Stiffening plates are welded to both sides of the bottom distribution beam corresponding to the sliding foot of the steel structure. The translational reaction back is formed by welding a square tube to the stiffening plate.

10. An installation method for a prefabricated assembled cap beam translation installation device under an existing bridge as described in any one of claims 1 to 9, characterized in that, Includes the following steps: Step 1: First, hoist the precast columns. After hoisting, install the steel pipe supports, connect and fix the steel pipe supports to the foundation, and install channel steel between the steel pipe supports for connection and reinforcement. Step 2: Install the steel structure distribution beam on the top surface of the steel pipe support by full welding to form a translation frame. After the frame is installed, level the top surface of the steel structure distribution beam. Step 3: Install a sliding track on the top surface of the leveling layer of the steel structure distribution beam, and install steel structure sliding feet inside the sliding track; Step 4: Install the bottom distribution beam on the top of the steel structure sliding foot, and at the same time install the limiting blocks at both ends of the bottom distribution beam. When hoisting the precast cap beam, it will be locked between the two limiting blocks. Step 5: Install and debug the PLC synchronous control unit, and move the precast cover beam to the predetermined position; Step Six: Verify the alignment accuracy of the precast columns and precast cap beams. If there is a deviation, use the correction unit for fine-tuning. Step 7: Install hydraulic jacks and follow-up jacks for lowering the precast cap beam at the bottom; Step 8: Install and debug the PLC synchronous control unit, lower the precast cap beam to the designed position, and complete the precise docking of the precast cap beam and the precast column.

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