Bridge longitudinal jacking and deviation rectifying method for high-speed railway track structure

Abstract

The invention relates to the technical field of ballast track structure repairing, in particular to a bridge longitudinal jacking and deviation rectifying method for a high-speed railway track structure, and longitudinal deviation rectifying of a beam body is achieved through the following steps under the condition that railway operation is not interrupted: firstly, a beam falling prevention stop block is dismantled; the longitudinal constraint of on-line rail fasteners and ballasts is removed scientifically according to the rail temperature; secondly, targeted transformation is conducted on an anchoring system under the support, and the anchoring space in the cushion stone is cut and expanded; then, a temporary support and a jacking system are installed, and the jacking system comprises a vertical jack set and a longitudinal jack with the adjacent beam body or abutment as the counter-force back; then, after passing through a test jacking and test translation verification system, carrying out formal jacking and longitudinal translation by adopting a displacement and pressure double-control synchronization technology; and finally, grouting and fixing the transformed support and recovering the bridge floor facility. The problem of longitudinal large displacement rectification of the high-speed railway bridge in the operation period is solved, the construction process is safe and controllable, and the precision is high.

Description

Technical Field

[0001] This application relates to the field of ballast track structure repair technology, and in particular to a method for longitudinal jacking and correction of bridges used in high-speed railway track structures. Background Technology

[0002] High-speed railways have extremely high requirements for the smoothness of ballasted track alignment. Even slight deviations can affect the stability of train operation and even threaten the safety of train operation. Engineering activities such as loading within the pier area, excavation of foundation pits, or mining of underground resources can all lead to bridge settlement and displacement, excessive track deformation, and damage to the smoothness of the track structure, requiring timely remediation and repair.

[0003] When settlement occurs on ballasted track bridges, track irregularities can be resolved by tamping the ballast and fine-tuning the track to adjust its position. However, when longitudinal displacement occurs on the bridge, the shear force on the bridge support structure and track structure increases, which may lead to shear failure of the support structure and failure of the fastening system in severe cases, affecting the stability of the structure and the safety of train operation.

[0004] Current beam shifting and correction techniques are mostly for small lateral displacements, which are relatively easy to implement due to the small amount of correction. However, for large longitudinal displacements of the beam, the amount of correction is large, there are many constraints on the line, and the construction space between beams and between abutments and beams is small, making construction difficult. Therefore, there is currently a lack of technology for longitudinal beam correction. Summary of the Invention

[0005] To address the current lack of technology for longitudinal alignment of bridge beams, this application provides a method for longitudinal lifting and alignment of bridges used in high-speed railway track structures.

[0006] This application provides a method for longitudinal jacking and correction of bridge tracks for high-speed railways, employing the following technical solution: A method for longitudinal jacking and correction of bridge tracks for high-speed railways includes the following steps: Remove longitudinal external constraints on the beams: Remove the anti-falling beam blocks between the beams and remove the longitudinal resistance of the online structure, including cleaning the ballast at the beam joints and loosening the track fasteners that affect the longitudinal displacement of the beams; Modify the bridge bearing anchorage system: Remove the lower bolt sleeves of the pier bearings and modify the anchorage structure of the bearings to provide the space required for longitudinal movement of the beam. Install temporary support and jacking system: Install temporary supports at the corresponding positions of the pier supports, arrange vertical jacks between the beam and the pier, and arrange longitudinal jacks to provide longitudinal thrust. Lifting and longitudinal translation: The beam is lifted by jacking the vertical jacks so that the beam is separated from the pier support. Then, longitudinal jacks are used to apply longitudinal thrust to the beam so that the beam is displaced and adjusted along the longitudinal direction of the line to complete the correction. Restoration and Fixation: After the longitudinal deviation of the beam is corrected, it is lowered back onto the pier support. The modified support anchorage system is then grouted and fixed. Finally, the temporary supports and construction equipment are removed, and the bridge deck facilities are restored.

[0007] This application solves the problem of correcting large longitudinal displacement of bridges under the condition that the high-speed rail does not stop operating. The method involves sequentially releasing constraints, modifying the system, lifting and translating, and restoring fixation. It not only achieves the correction target, but also ensures operational safety throughout the entire process, thus improving the current lack of technology for longitudinal correction of bridge beams.

[0008] Furthermore, the step of releasing the longitudinal external constraints of the beam includes: During the construction window, the ballast in the beam joint area, above and below the sleepers and between the tracks, is cleaned in stages. Based on the relationship between the measured rail temperature and the locked rail temperature, the rail fasteners within the range affected by the longitudinal movement of the beam are loosened in stages.

[0009] Step-by-step ballast removal minimizes disturbance to track foundation stability during construction, ensuring efficient and safe operation within limited track maintenance windows. By scientifically assessing temperature stress within the rails and developing differentiated fastener release plans, problems such as rail stress concentration caused by improper operation are avoided, improving construction controllability and safety.

[0010] Furthermore, based on the relationship between the measured rail temperature and the locked rail temperature, the steps for loosening the rail fasteners within the longitudinal displacement range of the beam include the following: When the measured rail temperature is not higher than the locked rail temperature, the sleeper fasteners in the pre-tightened part in the middle of the beam are loosened symmetrically to both sides by a specified number of sleeper fasteners. When the measured rail temperature is higher than the locked rail temperature but not higher than the first threshold, the sleeper fasteners are continuously loosened for no more than the first number of times, and some sleeper fasteners are pre-tightened within the loosening range. When the measured rail temperature is higher than the first threshold but not higher than the second threshold, the sleeper fasteners at the beam end joints are loosened continuously for no more than the second number of times. When the measured rail temperature is higher than the second threshold, it is prohibited to loosen the fasteners.

[0011] This step precisely quantifies and grades the strategy for loosening fasteners, forming a standardized construction guideline that is directly linked to rail temperature and is highly operable. This ensures that under complex working conditions, sufficient longitudinal constraints can be released to facilitate beam movement while maintaining track structure stability.

[0012] Preferably, the locking rail temperature is 28°C, the first threshold is 38°C, and the second threshold is 48°C; the first quantity is 20, and the second quantity is 9.

[0013] Furthermore, the steps for modifying the bridge bearing anchorage system include: Cut and remove the original lower bolt sleeve located inside the support pad stone, enlarge the sleeve hole on the support pad stone, and the enlarged hole length shall not be less than the designed longitudinal translation amount + 50mm; Welding or rebar installation is used to repair the steel mesh inside the supporting pad stone, and the hole walls are roughened.

[0014] The quantitative standard of "the enlarged hole length is not less than the design translation amount + 50mm" ensures that after the existing anchorage (lower bolt sleeve) is removed, sufficient longitudinal movement space is provided for the beam, while also preserving enough length for subsequent re-anchoring. Combined with the reinforcement mesh repair and roughening of the hole wall, this not only solves the movement space problem but also creates conditions for a firm bond between the new grout and the original pad concrete, ensuring the long-term durability and reliability of the support anchorage system after correction.

[0015] Furthermore, before the step of installing the temporary support and jacking system, a step of laterally widening the original pad stone of the pier is also included: according to the actual space width at the top of the pier, the widened part is poured on the side of the original pad stone, and the top surface of the widened part is flush with the top surface of the original pad stone, so as to provide sufficient space for the installation of the vertical jack group and temporary support.

[0016] By widening the pad stones laterally, the necessary working surface is provided for the jacking equipment and temporary supports, which improves the space constraints commonly encountered in longitudinal correction construction. This makes the entire correction method more adaptable to different sites, especially suitable for early-built bridges with limited space on the pier tops.

[0017] Furthermore, the step of installing the temporary support includes: Install a transition steel plate at the position corresponding to the pier support at the bottom of the beam; The upper part of the temporary support is connected to the conversion steel plate, and the lower part is anchored in the temporary cast or widened support pad stone by bolt sleeves. Before installing temporary supports, shear grooves are chiseled on the top of the pier or rebar is installed to increase the anti-slip capacity of the bottom of the temporary supports.

[0018] By converting steel plates to achieve a reliable connection with the bottom of the beam, and by chiseling shear grooves or installing reinforcement bars on the top of the pier to enhance the resistance to horizontal slippage at the bottom of the temporary support, it is ensured that the temporary support system can stably bear and transmit huge vertical loads and possible horizontal forces during the lifting and moving of the beam, providing a safe and stable temporary support platform for the beam after it is separated from the pier support.

[0019] Furthermore, in the step of installing the temporary support and jacking system, the longitudinal jacks are arranged as follows: Longitudinal jacks are placed at the joints between adjacent beams, or between the abutment and the beam. Utilize adjacent beams or abutments as a backing to provide reaction forces; When the space between beams is narrow, an ultra-thin jack is used as the longitudinal jack.

[0020] The design that uses adjacent beams or abutments as reaction backing utilizes existing structures, eliminating the need for additional large reaction foundations, simplifying construction, shortening the construction period, and reducing costs.

[0021] Furthermore, the lifting and longitudinal translation processes are synchronously controlled using a dual-control principle of displacement and pressure: The displacement synchronization error of each lifting point is controlled to be less than 1mm; The error between the actual pressure of any single jack and the average pressure within the group is controlled to be less than 5%; When the displacement or pressure error exceeds the limit value, the control system automatically closes the hydraulic check valve to lock the system.

[0022] Based on the principle of dual control of displacement and pressure, as well as control indicators, a closed-loop control system for the lifting and translation process is formed. Displacement synchronization control ensures the stability of the beam posture and prevents twisting. Pressure equalization control ensures uniform force on each support point and avoids local overload. The system has an automatic locking safety mechanism when the error exceeds the limit, realizing active safety protection.

[0023] Furthermore, the lifting and longitudinal translation steps include trial lifting and trial translation steps before the formal lifting and longitudinal translation are performed: The trial lifting includes lifting the beam, checking the system stability, and then lowering it back down, repeating this cycle multiple times. The trial translation includes performing short-distance longitudinal movements to verify the system's reliability and the stability of the monitoring data.

[0024] Before carrying out the large-stroke, high-load lifting and translation, small-displacement, low-risk trial lifting and translation are conducted first to comprehensively test the reliability and coordination of the hydraulic system, support structure, monitoring equipment and control logic, and to expose and eliminate potential fault points and risk sources in advance.

[0025] Furthermore, throughout the entire construction process, a multi-displacement monitoring system is established and operated, which includes: The first system is based on a wire-type displacement sensor, used for real-time control of the lifting and translation amounts; The second system: an independent elevation and displacement measurement system, used to measure the real-time spatial attitude of the box girder; The third system: an online track geometry detection system, used to monitor changes in track alignment; The fourth system: stress sensors installed inside the beam to monitor changes in internal stress. The monitoring results of the multi-displacement monitoring system are compared and verified with each other to ensure construction accuracy and safety.

[0026] By integrating four independent systems—a wire sensor (real-time control), an independent measurement system (spatial attitude), an online track inspection system (track alignment), and a beam internal stress sensor (structural internal force)—multi-dimensional and all-around monitoring of the construction process is achieved. The data from each system are cross-checked and mutually verified, which can effectively identify and eliminate errors or faults of a single sensor, ensuring the reliability of the monitoring data.

[0027] In summary, this application includes at least one of the following beneficial technical effects: 1. This application improves the problem of correcting longitudinal displacement defects in long-span bridges while ensuring uninterrupted safe operation of railway lines. Compared with existing technologies that only apply to small lateral displacement adjustments, this method addresses the challenges of complex constraints and limited space inherent in longitudinal correction. By systematically implementing steps such as releasing online constraints, modifying the anchorage system under the supports, constructing a temporary support system, high-precision jacking and translation, and in-situ restoration, it achieves precise adjustment of the longitudinal position of the beam. This helps avoid major safety hazards such as support shear failure and track geometry deterioration caused by long-term bridge offset, and significantly improves the long-term service safety and stability of high-speed railway infrastructure. 2. This application proactively modifies the anchorage system under the supports (e.g., precisely cutting bolt sleeves and reserving safety margins) to create physical space for the longitudinal movement of the beam, avoiding damage to the permanent structure during the jacking process. Secondly, by adopting a rail temperature-based fastener grading loosening strategy and a ballast step-by-step cleaning process, online constraints are scientifically released, releasing sufficient longitudinal freedom while maximizing the temporary stability of the track structure during construction. Simultaneously, by constructing a multi-redundant monitoring network integrating guy wire sensors, independent measurement systems, online track inspection, and stress monitoring, and combining synchronous jacking technology with displacement and pressure dual control, intelligent control of the entire construction process is achieved, ensuring the beam's stable posture and uniform stress during movement, helping to avoid the risk of local overload or instability of the structure. Attached Figure Description

[0028] Figure 1 This is a flowchart illustrating the method of an embodiment of this application; Figure 2 This is a schematic diagram of the modification of the inner bolt hole in an embodiment of this application; Figure 3 This is a schematic diagram of shear tooth groove chiseling in an embodiment of this application; Figure 4 This is a schematic diagram of the temporary pad stone casting and temporary support installation in the embodiments of this application; Figure 5 This is a schematic diagram of the modification of the outer bolt hole in an embodiment of this application; Figure 6 This is a schematic diagram of the vertical jack arrangement in an embodiment of this application; Figure 7 This is a schematic diagram of the longitudinal jack arrangement between the beams on the bridge piers in this embodiment of the application; Figure 8 This is a schematic diagram of the longitudinal jack arrangement between the bridge abutment and the beam in an embodiment of this application.

[0029] Attached reference numerals: 1. Existing pad stone; 2. Permanent support; 3. Modified inner sleeve hole; 4. Shear tooth groove; 5. Temporary pad stone; 6. Temporary support; 7. Modified outer sleeve hole; 8. Vertical jack assembly; 9. Longitudinal jack; 10. Ultra-thin jack. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-8 This application will be described in further detail.

[0031] This embodiment uses a 32-meter simply supported box girder bridge as an example. Due to the impact of adjacent construction work, one span of the bridge experienced a 35mm longitudinal offset, requiring correction and repositioning without interrupting train operation. This application discloses a method for longitudinal lifting and correction of bridges used in high-speed railway track structures. (Refer to...) Figure 1 The method for longitudinal jacking and correction of bridges used in high-speed railway track structures includes the following steps: Step 1: Release the longitudinal external constraints of the beam, specifically including: Step 1.1: Construction preparation and establishment of a monitoring system: During the railway maintenance "window" period, enclosed scaffolding and a circular operating platform on the pier top are erected around the bridge piers, and a multi-layered displacement monitoring system is established, including: The first system (control quantity monitoring): high-precision wire-type displacement sensors (accuracy 0.01mm) are installed at the four corners of the beam. The signals are connected to the central PLC control system for real-time feedback of jacking and translation. The second system (attitude monitoring): Multiple prisms are arranged on the top and side surfaces of the beam, and two total stations are used to perform independent and synchronous three-dimensional coordinate measurements to monitor the spatial attitude and displacement of the box girder in real time. The third system (track monitoring): connects to the online track geometry status detection system (track inspection trolley data) in this section to monitor changes in track elevation, alignment and level throughout the entire process; The fourth system (internal force monitoring): resistance strain gauges are pre-attached to the bottom plate and web near the beam supports to monitor the changes in internal stress of the beam throughout the construction process.

[0032] Before construction begins, the initial data values ​​of the four systems are recorded. During construction, the data from the four systems are displayed in real time on the command center's large screen and compared with each other. Any abnormal deviation will trigger an early warning.

[0033] Step 1.2: Remove the anti-fall beam blocks and clean the ballast: Remove the steel blocks between the beam ends to prevent the beam from falling.

[0034] Step-by-step cleaning of ballast in beam joints: First, within the skylight point, bag and remove the ballast above the sleepers within 1 meter on both sides of the beam joint; on the day of the formal jacking and horizontal movement, hollow out the ballast at least 0.5 meters deep under the sleepers in this area to create space for the longitudinal movement of the beam.

[0035] Step 1.3: Sectional loosening of fasteners based on rail temperature: The track temperature was set at 28℃; on the day of construction, the actual measured track temperature T was 25℃ (T<28℃), and the corresponding strategy was implemented: Pre-tighten the fasteners of 10 sleepers in the middle of the beam. Using this as the center, symmetrically loosen the fasteners of 27 sleepers on each side of the track. Before loosening the fasteners, evenly install 4 gauge tie rods between the sleepers to maintain the stability of the track frame.

[0036] Step 2: Modify the bridge bearing anchorage system, specifically including: Step 2.1, Enlarging the Sleeve Hole: Cut and remove the original lower bolt sleeve located inside the original pad stone 1. Use a drilling rig to enlarge the lower anchor sleeve hole of the permanent support 2 on the original pad stone 1 along the longitudinal direction of the bridge (correction direction). Based on the design longitudinal translation of 30mm, calculate the enlarged hole length to be no less than 30mm + 50mm = 80mm; reinstall the lower bolt sleeve and connect it to the lower anchor plate of the support through the lower anchor bolt. The operation of enlarging the sleeve hole can be carried out in steps. First, perform the enlargement operation of the inner sleeve hole. The modified inner sleeve hole 3 is as follows. Figure 2 As shown.

[0037] Step 2.2, Repair and Treatment: Weld the steel mesh inside the pad stone that was damaged during the cutting process, and roughen the walls of the new concrete holes after enlargement to enhance the adhesion between the old and new materials.

[0038] Step 3: Install temporary support and jacking system, specifically including: Step 3.1, lateral widening of the bearing pad: Several shear grooves 4, 5cm deep and 5cm wide, are chiseled on the side of the original bearing pad 1 at the top of the pier, such as... Figure 3As shown; then, formwork is erected on the side of the original pad stone 1, and high-strength, early-strength concrete is poured to widen the pad stone by 35cm, forming a temporary pad stone 5, as shown. Figure 4 As shown, ensure that the top surface of the widened part is flush with the top surface of the original pad stone 1.

[0039] Step 3.2, Install temporary support 6: Install a 40mm thick conversion steel plate at the position corresponding to permanent support 2 at the bottom of the beam, and connect it to the pre-embedded parts at the bottom of the beam with bolts; install temporary support 6, with its top connected to the conversion steel plate with bolts, and its bottom anchored in the temporary pad stone 5 with the pre-embedded bolt sleeve, and fix it with high-strength grout; adjust the top pad of temporary support 6 so that its top surface is slightly lower than the bottom of the beam by 1-2mm.

[0040] Step 3.3: Enlarge the remaining sleeve holes (outer sleeve holes) of the original support anchoring system, using the same method as in Step 2.1; the modified outer sleeve hole 7 is as follows. Figure 5 As shown.

[0041] Step 3.4: Deploy the jacking system, including the following steps: Set up 8 vertical jacks: such as Figure 6 As shown, a set (4 units) of vertical jacks are arranged between the beam and the pier top at each permanent support 2. The bottom of the jacks is fixed to the pier top, and a polytetrafluoroethylene sliding plate is installed between the top of the jacks and the bottom of the beam. Install longitudinal jacks 9: such as Figure 7 and Figure 8 As shown, longitudinal jacks 9 are placed in the beam joint between adjacent beams, using the adjacent beams as a backing to provide reaction force. The jack cylinder is fixed to the end of the next beam, and the piston rod pushes the beam that needs to be corrected. When the beam joint space is narrow, ultra-thin jacks 10 are used.

[0042] Step 4, Lifting and longitudinal translation, specifically includes: Step 4.1, Trial Lifting and Trial Translation, includes the following steps: Trial lifting: Start the vertical jack assembly 8 to steadily lift the beam by 3mm, hold the load for 5 minutes, and check the hydraulic system, temporary support 6, and all monitoring system data. After confirming that everything is correct, lower it back down and repeat the cycle 3 times. Trial translation: Start the longitudinal jack 9 and push the beam 5mm in the reset direction at a speed of 1mm / min to check the reliability and coordination of the reaction structure, sliding surface and monitoring system.

[0043] Step 4.2, the simultaneous construction of formal jacking and translation, includes the following steps: Formal Lifting: Activate vertical jack group 8 to synchronously lift the beam at a speed of 0.5 mm / min. The PLC control system strictly adheres to the principle of dual control of displacement and pressure. In terms of displacement control, the displacement sensor readings of each vertical jack are compared in real time to ensure that the displacement synchronization error is always less than 1 mm (actually controlled within 0.5 mm). In terms of pressure control, the oil pressure of each jack is monitored in real time to ensure that the error between the actual pressure of any jack and the average pressure within the group is less than 5%.

[0044] Formal translation: Start longitudinal jack 9 and push longitudinally at a speed of 1mm / min, adhering to the dual-control principle, and keeping the longitudinal displacement synchronization error within 1mm; pause briefly at 10mm and 20mm for a comprehensive check. When the displacement or pressure error approaches the limit value, the control system automatically closes the hydraulic check valve and locks the system, continuing only after adjustments are confirmed; finally, the beam is precisely pushed to the designed correction position of 30mm, with the track geometry remaining stable throughout the process.

[0045] Step 5, Restoration and Fixation, specifically includes: Step 5.1, Support Grouting and Fixing: After the beam is accurately positioned, formwork is erected under the bottom plate of permanent support 2 and in the modified bolt holes. High-strength non-shrink grout is used for gravity grouting to ensure compaction.

[0046] Step 5.2, Load Transfer and Removal: After the grouting material reaches the design strength (≥20MPa), the vertical jack assembly 8 is unloaded in stages to smoothly transfer the beam load to the permanent support 2. Subsequently, all temporary supports 6, jacks, and reaction devices are removed.

[0047] Step 5.3, Track Restoration: Backfill and compact the ballast in the beam joints, restore the track fasteners according to the regulations (including the final stress release operation on the 10 sleeper fasteners in the middle of the beam), reinstall the sound barriers, railings and other bridge deck facilities, and clean up the site.

[0048] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for longitudinal jacking and correction of bridge tracks for high-speed railways, characterized in that: Includes the following steps: Remove longitudinal external constraints on the beams: Remove the anti-falling beam blocks between the beams and remove the longitudinal resistance of the online structure, including cleaning the ballast at the beam joints and loosening the track fasteners that affect the longitudinal displacement of the beams; Modify the bridge bearing anchorage system: Remove the lower bolt sleeves of the pier bearings and modify the anchorage structure of the bearings to provide the space required for longitudinal movement of the beam. Install temporary support and jacking system: Install temporary supports at the corresponding positions of the pier supports, arrange vertical jacks between the beam and the pier, and arrange longitudinal jacks to provide longitudinal thrust. Lifting and longitudinal translation: The beam is lifted by jacking the vertical jacks so that the beam is separated from the pier support. Then, longitudinal jacks are used to apply longitudinal thrust to the beam so that the beam is displaced and adjusted along the longitudinal direction of the line to complete the correction. Restoration and Fixation: After the longitudinal deviation of the beam is corrected, it is lowered back onto the pier support. The modified support anchorage system is then grouted and fixed. Finally, the temporary supports and construction equipment are removed, and the bridge deck facilities are restored.

2. The method for longitudinal jacking and correction of bridges for high-speed railway track structures according to claim 1, characterized in that: The steps for releasing the longitudinal external constraints of the beam include: During the construction window, the ballast in the beam joint area, above and below the sleepers and between the tracks, is cleaned in stages. Based on the relationship between the measured rail temperature and the locked rail temperature, the rail fasteners within the range affected by the longitudinal movement of the beam are loosened in stages.

3. The method for longitudinal jacking and correction of bridges for high-speed railway track structures according to claim 2, characterized in that: Based on the relationship between the measured rail temperature and the locked rail temperature, the following steps are taken to loosen the rail fasteners within the range of influence of the longitudinal displacement of the beam: When the measured rail temperature is not higher than the locked rail temperature, the sleeper fasteners in the pre-tightened part in the middle of the beam are loosened symmetrically to both sides by a specified number of sleeper fasteners. When the measured rail temperature is higher than the locked rail temperature but not higher than the first threshold, the sleeper fasteners are continuously loosened for no more than the first number of times, and some sleeper fasteners are pre-tightened within the loosening range. When the measured rail temperature is higher than the first threshold but not higher than the second threshold, the sleeper fasteners at the beam end joints are loosened continuously for no more than the second number of times. When the measured rail temperature is higher than the second threshold, it is prohibited to loosen the fasteners.

4. The method for longitudinal jacking and correction of bridges for high-speed railway track structures according to claim 1, characterized in that: The steps for modifying the bridge bearing anchorage system include: Cut and remove the original lower bolt sleeve located inside the support pad stone, enlarge the sleeve hole on the support pad stone, and the enlarged hole length shall not be less than the designed longitudinal translation amount + 50mm; Welding or rebar installation is used to repair the steel mesh inside the supporting pad stone, and the hole walls are roughened.

5. A method for longitudinal jacking and correction of bridges used in high-speed railway track structures according to claim 1, characterized in that: Before the installation of the temporary support and jacking system, the method further includes a step of widening the original pad stone of the pier laterally: according to the actual space width at the top of the pier, the widened part is poured on the side of the original pad stone, and the top surface of the widened part is flush with the top surface of the original pad stone to provide sufficient space for the installation of the vertical jack assembly and temporary support.

6. The method for longitudinal jacking and correction of bridges for high-speed railway track structures according to claim 1, characterized in that: The steps for installing the temporary support include: Install a transition steel plate at the position corresponding to the pier support at the bottom of the beam; The upper part of the temporary support is connected to the conversion steel plate, and the lower part is anchored in the temporary cast or widened support pad stone by bolt sleeves. Before installing temporary supports, shear grooves are chiseled on the top of the pier or rebar is installed to increase the anti-slip capacity of the bottom of the temporary supports.

7. A method for longitudinal jacking and correction of bridges used in high-speed railway track structures according to claim 1, characterized in that: In the step of installing the temporary support and jacking system, the longitudinal jacks are arranged as follows: Longitudinal jacks are placed at the joints between adjacent beams, or between the abutment and the beam. Utilize adjacent beams or abutments as a backing to provide reaction forces; When the space between beams is narrow, an ultra-thin jack is used as the longitudinal jack.

8. A method for longitudinal jacking and correction of bridge tracks for high-speed railways according to claim 1, characterized in that: The lifting and longitudinal translation processes are synchronously controlled using a dual-control principle of displacement and pressure. The displacement synchronization error of each lifting point is controlled to be less than 1mm; The error between the actual pressure of any single jack and the average pressure within the group is controlled to be less than 5%; When the displacement or pressure error exceeds the limit value, the control system automatically closes the hydraulic check valve to lock the system.

9. A method for longitudinal jacking and correction of bridges used in high-speed railway track structures according to claim 1, characterized in that: The lifting and longitudinal translation steps include trial lifting and trial translation steps before the formal lifting and longitudinal translation are performed. The trial lifting includes lifting the beam, checking the system stability, and then lowering it back down, repeating this cycle multiple times. The trial translation includes performing short-distance longitudinal movements to verify the system's reliability and the stability of the monitoring data.

10. A method for longitudinal jacking and correction of bridges for high-speed railway track structures according to claim 1, characterized in that: Throughout the construction process, a multi-displacement monitoring system was established and operated, which included: The first system is based on a wire-type displacement sensor, used for real-time control of the lifting and translation amounts; The second system: an independent elevation and displacement measurement system, used to measure the real-time spatial attitude of the box girder; The third system: an online track geometry detection system, used to monitor changes in track alignment; The fourth system: stress sensors installed inside the beam to monitor changes in internal stress. The monitoring results of the multi-displacement monitoring system are compared and verified with each other to ensure construction accuracy and safety.

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