Box culvert jacking construction system and method for urban rail transit interval overpass connection

Abstract

The invention belongs to the technical field of buildings, and discloses a box culvert jacking construction system and method for urban rail transit interval overpass connection, and the system comprises a counterweight setting and unloading module which comprises a steel ingot counterweight, a steel bar counterweight and an unloading counterweight; the jacking force calculation system is used for carrying out jacking force calculation; the jacking equipment and mounting module comprises a hydraulic system, force transmission equipment and equipment mounting and debugging; the jacking excavation module is used for jacking excavation; the jacking construction module comprises measures of inspection before jacking, test jacking, jacking and deviation correction; and the construction monitoring module comprises measurement monitoring in the jacking process, existing subway monitoring and box body monitoring and control during box culvert jacking operation. The construction method effectively solves the problems of short construction period, short maintenance time of the prefabricated box culvert, steel ingot counterweight and open excavation jacking in an overpass subway shield interval in the project. Corresponding quality targets, safety targets and green construction targets are achieved.

Description

Technical Field

[0001] The present invention belongs to, but is not limited to, the field of construction technology, and particularly relates to a box culvert jacking construction system and method for overcrossing connection in urban rail transit intervals. Background Art

[0002] The foundation pits of Plot 604 and Plot 605 within the scope of the comprehensive transportation hub project are located on the southwest side of the project. The underground structure of Plot 604 adopts a frame structure system, the ordinary floor adopts a cast-in-place reinforced concrete floor slab system, the number of underground structure layers is 2, and locally it is 1 layer. A civil air defense project is set on the B2 layer, and the civil air defense grade is Class A nuclear grade 6 and normal grade 6; the foundation pit adopts a soil nail slope protection form, the bottom elevation of the pit is 10.300m, the top elevation of the raft slab is 12.500m, and the thickness of the raft slab is 2m. The underground structure of Plot 605 adopts a frame structure system, the ordinary floor adopts a cast-in-place reinforced concrete floor slab system, and the number of underground structure layers is 3; civil air defense projects are set on B3 (partial area) and B2 (partial area), and the civil air defense grade is grade 6; the foundation pit adopts a diaphragm wall support form, with a 5m slope cut-off at the upper part, the bottom elevation of the pit is 7.500m, the top elevation of the raft slab is 9.200m, and the thickness of the raft slab is 1.5m. The connecting passage is a passage connecting Plot 604 and Plot 605.

[0003] The ground elevation of the plot in the connecting passage area is the absolute elevation of 22.500m, the planned ground elevation is 25.000m, and the anti-floating water level is 19.500m. The following difficulties exist in this project: overcrossing the subway shield interval, tight construction period, short maintenance time for precast box culverts, steel ingot counterweight, and open cut jacking. Summary of the Invention

[0004] In view of the problems existing in the prior art, the present invention provides a box culvert jacking construction system and method for overcrossing connection in urban rail transit intervals.

[0005] The present invention is implemented as follows. A box culvert jacking construction system for overcrossing connection in urban rail transit intervals, the system includes: a counterweight setting and removal module, including steel ingot counterweight, steel bar counterweight, and counterweight removal; a jacking force calculation system for performing jacking force calculation; a jacking equipment and installation module, including a hydraulic system, a force transmission device, equipment installation and commissioning; a jacking excavation module for jacking excavation; a jacking construction module, including pre-jacking inspection, trial jacking, jacking, and deviation correction measures; a construction monitoring module, including measurement and monitoring during jacking, monitoring of the existing subway, and monitoring and control of the box body during box culvert jacking operation.

[0006] Furthermore, the steel ingot counterweight specifically includes: (1) Place steel ingot counterweight blocks with dimensions of 3m × 1.5m × 0.5m on the precast culvert floor slab. Each counterweight block weighs 17.5t, and a total of 144 blocks are configured, with a total weight of 2520t; (2) Place two stacks of counterweight blocks horizontally in a row, with each stack stacked in three layers and placed longitudinally in 24 rows; the counterweight blocks are placed close to the two side axils, with a passageway with a width of not less than 1.1m reserved in the middle; a spacing of approximately 150mm is reserved between each row of counterweight blocks; (3) The precast culvert is jacked forward empty on the slide plate for about 8 - 9m. When approaching the boundary of the key protection area, it is not allowed to enter the key protection area; the counterweight blocks are sent into the culvert from the east side opening of the culvert by a 20t forklift and stacked neatly row by row from west to east; (4) Build a ramp on the top support and jacking equipment with steel plates and support frames, place a 20t forklift on it, and configure a 300t crawler crane on the ground. The crawler crane is used for hoisting in cooperation with the forklift for transfer. The counterweight blocks are hoisted with a steel wire rope hung by a supporting special pin, and the forklift places the counterweight blocks at the designated positions inside the culvert.

[0007] The steel bar counterweight specifically includes: (1) Place steel plates with dimensions of 6m × 2.2m × 0.02m on the precast culvert roof slab; a total of 1200 sheets, each sheet weighing about 2.1t, with a total weight of about 2520t; (2) Place the steel plates longitudinally along the east - west direction of the culvert roof slab, with 50 sheets in each stack, and place 4 stacks side by side, and place them in 6 rows along the length of the culvert; (3) Before placing the steel plate counterweight, set up a 0.9m - wide socket - type disk - type buckle support frame for back - topping support along the center line of the culvert interior lengthwise, and place adjustable bases and adjustable brackets on the upper and lower parts respectively. Place square timbers or steel channels on the adjustable brackets.

[0008] The removal of the counterweight specifically includes: (1) After the culvert is jacked into place, seal and pour fluidized solidified soil at both ends of the gap between the supporting piles on both sides of the culvert; return the construction site of the plot, and the subsequent main foundation pit structure construction can be carried out on Plot 604; at the same time, excavate and construct the cast - in - place structures on both sides. First, construct the cast - in - place structure connecting with Plot 605 on the west side, and then construct the cast - in - place structure connecting with Plot 604 on the east side; (2) After the cast - in - place structure construction of the connecting channel with Plot 605 is completed, backfill the soil above the roof slab layer by layer according to the planned ground elevation. After the cast - in - place structure floor slab of the connecting channel with Plot 604 is completed and its strength reaches 80% of the designed strength, combined with the monitoring and measurement results, remove the steel ingot counterweight inside the culvert from the east side, and keep the counterweight on the culvert roof unchanged. When necessary, add emergency counterweights on the roof slab within the range of the culvert side walls; (3) After the cast - in - place structure roof slab of the connecting channel with Plot 604 is completed, combined with the monitoring and measurement results, gradually remove the steel plate counterweight on the roof slab and backfill the soil section by section; the length of each steel ingot removal shall not be greater than 3m, and the steel plate counterweight is 6m long. The steel plate counterweights in the same row can be removed in batches, and then backfill the soil and compact it immediately; when necessary, place emergency steel ingot counterweight blocks.

[0009] Furthermore, the jacking force calculation specifically includes: , where K is taken as 1.2; N1 is the total load on the top of the culvert box, which is the counterweight placement weight of 5242 t here; f1 is the friction coefficient between the upper surface of the culvert box and the load on the top, and for open cut jacking, F1 = 0; N2 is the self-weight of the culvert box of 2622 t; f2 is the friction coefficient between the bottom plate of the culvert box and the foundation soil, taken as 0.7; E is the earth pressure on both sides of the framed bridge culvert (kN), with pile support on both sides, the backfill can be cancelled, and the side pressure is not considered temporarily; f3 is the side friction coefficient, taken as 0.7; R is the frontal resistance of the cutting edge (kN / m 2 ); A is the frontal area of the cutting edge (m 2 ).

[0010] Furthermore, the jacking equipment and installation module specifically include: (1) Hydraulic system, which consists of a power mechanism, a high-pressure oil pump, a control mechanism, such as an electro-hydraulic control valve, a regulating valve, an electric control box, a jack, and auxiliary devices, such as an oil tank, oil pipes, hydraulic components, a pressure gauge, etc.; (2) Force transmission equipment, the reaction force is provided by a reinforced concrete reaction beam, and the dimensions of the reaction beam are: length 11.8 m, thickness 2.0 m, height 5.3 m; the force transmission equipment of the jacking frame is a 20-mm-thick steel backing plate, jack posts, distribution crossbeams, and jack post crossbeams, etc., and the jack posts are welded and fabricated using H-shaped steel; (3) Equipment installation, each component of the hydraulic system, such as the jack, high-pressure oil pump, electro-hydraulic control valve, electric control box, various instruments, etc., shall be subjected to a single test after overhaul, and can be installed only after passing the test; the power mechanism, high-pressure oil pump, oil tank, control mechanism, and auxiliary devices are arranged on the top plate of the culvert box, and the supporting high-pressure oil pipes and distribution oil pipes are connected to the jacks; the inner diameter of the oil pipes of the hydraulic system is determined by the oil volume, but the inner diameter of the main oil pipe of the return oil pipeline shall not be less than 10 mm, and the inner diameter of the branch oil pipe shall not be less than 6 mm; the oil pipes shall be cleaned, the oil circuit layout shall be reasonable, the sealing shall be good, and the hydraulic grease shall be filtered; 10 m × 0.9 m, 20-mm-thick steel backing plates are padded on the side of the bottom plate of the culvert box, and 20 500-t jacks are arranged in sequence from the middle line to both sides for installation; a jack post is installed corresponding to each jack, and the jack post shall be consistent with the jacking force axis and perpendicular to the crossbeam and the back beam; 10 m × 0.9 m, 20-mm-thick steel backing plates are installed on the back wall, and a cross bracing beam is installed; when the jacking length is long, a cross bracing beam is added every 4 m to 8 m; the jack posts and crossbeams for force transmission shall be prepared in accordance with the planned specifications and quantities and shall be overhauled before installation; (4) Commissioning: The purpose of the commissioning work is to comprehensively check whether the hydraulic components are reliable, whether there are any abnormalities in the functions of the jacks, whether the pipelines are leaking, adjust the working pressure of the relief valve, and gradually increase the oil pressure to push the box body, measure the starting thrust, and check the changes in the back; after all the hydraulic systems are installed, connect the circuits for trial operation, check the oil circuit, control valves, jacks, oil pumps, circuits, control boxes, and supporting auxiliary equipment, etc., to make them operate normally; after the hydraulic system is debugged and operates normally, apply the jacking force to make the force transmission equipment bear the force, and carefully check the force transmission equipment to meet the requirements of jacking.

[0011] Furthermore, the jacking and excavation module specifically includes: (1) For the jacking and excavation of the box culvert, mechanical excavation is adopted, and the soil is excavated step by step in the reverse direction of the jacking progress following the jacking step distance; two excavators are selected for the excavation operation. One 330-type excavator stands on the cross bracing beam for batch earth excavation, and one long-arm excavator stands on the platform outside the retaining wall to cooperate in cleaning the foundation base; when mechanically excavating, to prevent over-excavation and disturbing the original soil layer at the bottom, 20 cm of the foundation base soil is reserved for manual excavation; the excavator at the lower position excavates the soil to 1.5 m outside the retaining wall, and the loader cooperates with the dump truck to promptly transfer and transport the soil, and no soil shall be piled on the platform; (2) Before jacking and excavation, first backfill the soil excavated from the cross bracing beam during construction. The backfill soil is higher than and covers the cross bracing beam by no less than 300 mm. The excavator at the lower position parks on the backfill soil layer for the excavation operation of the jacking foundation pit; (3) For the jacking of the box culvert, excavation is carried out first, and then jacking is immediately carried out. The excavation footage each time shall not be greater than 0.4 m; the front of the box culvert structure is excavated with a slope, and the slope ratio is 1:1; the excavation work shall maintain close contact with the three-party monitoring personnel, and the excavation footage shall be appropriately controlled according to the monitoring results, soil conditions and the jacking stroke of the jacks; (4) When jacking while eating soil, the excavation bottom surface is 8 - 10 cm higher than the bottom surface of the box body. If the soil is soft, the excavation bottom surface is appropriately raised; during excavation, it is necessary to ensure "four non-excavations", that is, do not excavate when starting the jacking, do not excavate when the equipment fails, do not excavate when there is no jacking for a long time, and do not excavate before shift handover; (5) The excavation operation shall be uniformly commanded by the on-site construction responsible person. Before each excavation, the on-site construction responsible person shall conduct a comprehensive inspection and confirmation, and the on-site quality responsible person shall monitor. It is not allowed to excavate ahead of time; the excavation work shall cooperate closely with the surveying personnel, and the excavation method shall be improved at any time according to the jacking direction and deviation situation of the box body; (6) During excavation, it is strictly prohibited to randomly over-excavate or under-excavate. Excavation is carried out from top to bottom. It is strictly prohibited to dig soil from the lower part and to dig against the slope. Keep the surface smooth and jack while digging; (7) During the construction process, it is necessary to prevent the collapse of the soil to ensure the safety of traffic and personnel; if a collapse occurs during excavation and affects traffic safety, quickly organize emergency repair and reinforcement.

[0012] Furthermore, the jacking construction module specifically includes: (1) Inspection before jacking: Conduct a comprehensive inspection of the culvert structure before jacking. The waterproof layer and waterproof protective layer should be completed according to the design requirements. The concrete strength of the culvert structure and the top protective layer should reach the design strength requirements, and the strength report of the same-condition test blocks of the main structure concrete should be inspected. Conduct a comprehensive inspection of the back beam before jacking. The construction of the back beam and steel inclined struts should comply with the design, and the concrete of the back beam should reach the design strength requirements. Check whether the unconfined compressive strength of the soil after grouting reinforcement with sleeve valves meets the design requirements. All jacking equipment has been debugged and meets the requirements of jacking construction. All types of construction machinery are in place and have passed the acceptance. The installation and trial operation of the hydraulic system are all normal and meet the jacking requirements. The counterweights for the culvert floor and roof have been delivered or prepared according to the plan and meet the requirements of being placed in place in a timely manner after empty jacking. The on-site lighting installation is completed, and the lighting range and brightness should meet the construction requirements. The observation instruments, observation marks, and scales are installed, aligned with the reference points after calibration, and the initial readings should be measured. For excavation and jacking, the project management personnel conduct technical disclosures to the excavation and jacking personnel, clarify the work scopes and responsibilities of the earthwork unit and the jacking unit, stipulate the excavation method, the advance of each excavation, and the operation connection signals, and determine the liaison personnel on both sides. (2) Trial jacking: The trial jacking work generally ends when the box body is moved. Therefore, during the trial jacking, it is necessary to strengthen the observation of the center line, level, and longitudinal displacement of the box body, and at the same time pay attention to the changes in the back and the floor. The trial jacking work is to operate all the jacks to jack out together. When the jacking block touches the back, the oil pressure gradually increases. When the starting resistance of the box body is overcome and the box body is jacked, the pressure drops rapidly. At this time, the highest pressure value on the pressure gauge, after conversion, is the starting thrust of the box body. Considering the pressure loss in the pipeline and overcoming the internal friction resistance of the jacks, the actual thrust is based on 0. of the thrust reflected by the pressure gauge.Around 97, when making a trial jacking, there should be a dedicated person responsible for each relevant part to pay attention to the changing situation at any time; after starting the pump, when the oil pressure rises by 5 - 10 MPa, the pump must be stopped to observe the construction environment around the culvert box and the measurement data, and deal with any abnormalities in a timely manner; when the piston of the jack starts to extend and the jacking post is tightened, the jacking should be immediately stopped. After checking that there are no abnormalities in each part, the pump can be restarted and the data recorded; after the trial jacking, a comprehensive inspection should be carried out again. If the conditions of each part are all good, the formal jacking operation can be carried out; (3) Jacking: It is required to reserve a working pit to meet the requirement of prefabricating the entire culvert box in one piece. Therefore, the one-time jacking method is selected for the jacking construction; the jacking operation is divided into several stages: culvert box startup, empty jacking, excavation and jacking, jacking in place, and removal of jacking equipment; once the jacking operation starts, it should be continuously constructed, and each process should be closely coordinated; before jacking, a plan for the arrangement and combination of jacking posts should be formulated, and jacking posts of different specifications and dimensions should be arranged and combined; when the culvert box is jacked empty on the slip form of the working pit, special attention should be paid to the axial direction of the culvert box; the jacking forces on both sides of the axis should be adjusted in a timely manner according to the deviation to make the culvert box enter the soil along the designed axis direction; when lateral deformation of the line is found during jacking, the jacking should be immediately stopped and corrected in a timely manner; after the front section of the culvert box starts to take soil, the speed of excavation and soil removal should be increased, and continuous operation should be carried out day and night to keep the culvert box continuously jacking; after entering the bottom layer grouted and reinforced by sleeve valves, the excavation advance per time shall not be greater than 0.4 m; before each jacking, the hydraulic system, force transfer equipment, cutting edge, back wall and slip form, etc. should be checked, and any problems found should be dealt with in a timely manner; when the culvert box starts up, there should be a dedicated person observing each part and the observation points; after starting the pump, the pressure should be increased in stages. When the oil pressure rises by 5 MPa - 10 MPa each time, the pump should be stopped for inspection once, and any abnormalities found should be dealt with in a timely manner; during jacking, it is strictly prohibited to stand people near the jacking posts, crossbeams, etc. and the back wall. Observe the stress condition of the jacking posts in the safety area to prevent accidents caused by the jacking posts arching and bursting out; the jacking of the culvert box and the excavation and transportation of soil should be carried out alternately in a cycle, and the excavation operation should be started in a timely manner during the process of replacing the jacking iron according to the connection signal, and should be completed as much as possible at the same time, and the working surface should not be excavated in advance and wait for jacking; for each advance of one jacking stroke, different specifications of jacking irons and jacking posts should be connected and replaced as the jacking length increases, straightened according to the axial direction, and should be perpendicular to the crossbeam and the back wall. The contact surface should be wedged tightly with steel plates; to prevent possible instability after the jacking posts are lengthened, fill the soil on the jacking posts and compact it or place counterweight blocks; for each advance of one jacking stroke of the culvert box, the axis and elevation should be observed, and any deviation found should be corrected in a timely manner; before the handover of each shift, the jacks, oil pump hydraulic system, jacking posts, back wall and platform and other equipment should be carefully checked to keep the equipment in good condition; records should be made during the jacking process and handed over with the shift; during jacking, the observers should record the advance per jacking stroke, the deviation of the axis and elevation, the number of jacks opened, the oil pump pressure, the instantaneous jacking force, etc. for each jacking stroke, and should notify the on-site commanders in a timely manner with a report form of the jacking deviation so that they can take measures to correct it; the stop time during jacking should not exceed 2 h.

[0013] Furthermore, the construction monitoring module specifically includes: (1) measurement and monitoring during the jacking process: the observation instrument for monitoring the jacking process of the box culvert is set outside the back force influence area, and rainproof lighting facilities are set at the same time; during the jacking construction, full-time measurement personnel continuously observe, record, analyze and control the various parts of the box culvert, the jacking system and the back; when the box culvert is found to be deformed or displaced, the technical person in charge is immediately reported to analyze the cause and make corresponding adjustments to the jacking system to ensure the safety of the jacking construction; during the jacking process, the box culvert axis, elevation and box culvert structure deformation are continuously monitored; the deformation and lateral stability of the jacking column (jacking iron) axis direction are kept under observation, and the deformation near the contact beam support point is observed. , ensure that the force transmission structure system works normally; observe the back deformation and cracks in the soil in the force-affected area; maintain close contact with the third-party monitoring unit, and understand and grasp the monitoring data of Metro Line 6, roadbed and isolation piles between lines in real time to ensure the smooth implementation of the jacking work; (2) Monitoring precautions: Monitoring information should be fed back in a timely manner, and a good communication and data exchange mechanism should be established with the monitoring unit; before starting work, the current status of surrounding buildings and pipelines should be investigated, and monitoring should be strengthened during construction. Cracks and settlements in buildings and pipelines, as well as corresponding construction conditions and measures taken, should be recorded accordingly; monitoring should be based on special instrument measurements or special test components to obtain quantitative data, with actual On-site visual inspection is supplementary; the time intervals for various monitoring tasks are determined according to the construction progress, and monitoring should be intensified in places with complex stress changes or when abnormal conditions occur; all measuring points should reflect the changes in stress or deformation at the measuring point over time during construction, that is, from the start of construction to completion and until the observation data tends to be stable; monitoring projects should formulate monitoring and measurement control standards according to the principle of "zoning, grading, and phasing", and provide feedback and control according to the three-level warning of yellow, orange and red; in the monitoring work, the monitoring team should work closely with relevant units and personnel, and should ensure the rationality of the monitoring plan, the authenticity of the monitoring data, the stability and reliability of the measuring points and instruments, the timeliness of data processing and feedback, and the monitoring cycle. The integrity of the monitoring results should be fed back to the construction unit, design unit and supervision unit in a timely manner; (3) Existing subway monitoring: Entrust a qualified third-party monitoring unit to be responsible. During the construction process, we will strengthen communication and contact with the monitoring unit, receive feedback information in a timely manner, and actively cooperate with the construction unit, operating company and monitoring unit to prepare response measures for various emergencies to ensure construction safety; (4) Box culvert box body monitoring and control during jacking operation: From the start of jacking to the empty jacking stage before the box culvert enters the soil, the guide rail is mainly used to control the direction of the steel rail placed between the guide pier and the box culvert; during the jacking process, the horizontal deviation and directional deviation of the box culvert and the deformation of the back should be monitored. If there is any deviation, measures should be taken to correct it in time.

[0014] Another object of the present invention is to provide a box culvert jacking construction method for the upper cross-connection of urban rail transit sections based on the box culvert jacking construction system for the upper cross-connection of urban rail transit sections. The method is characterized in that the method specifically includes: S1: Using the counterweight setting and removal module to perform ingot counterweight, steel bar counterweight, and counterweight removal; S2: Using the jacking force calculation system to calculate the jacking force; S3: Using the jacking equipment and installation module to install and debug relevant hydraulic systems and force transmission equipment; S4: Using the jacking excavation module to perform jacking excavation; S5: Using the jacking construction module to perform pre-jacking inspection, trial jacking, jacking, and deviation correction measures; S6: Using the construction monitoring module to perform measurement monitoring during jacking, monitoring of existing subways, and monitoring and control of the box culvert during box culvert jacking operations.

[0015] Combined with the above technical solutions and the solved technical problems, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows: The present invention provides a systematic box culvert jacking construction method and system for the upper cross-connection of urban rail transit sections. In view of the complex environment of crossing over an existing subway shield tunnel, by using the technical means of organically combining ingot counterweight, steel plate counterweight and hydraulic jacking equipment, it is possible to accurately control the jacking force and the attitude of the box culvert under the strictly limited space and load conditions, effectively overcoming the problems of structural deformation and shield tunnel risks caused by insufficient counterweight or control instability in traditional construction. Through the jacking force calculation system and construction monitoring module of the present invention, the jacking axis, elevation of the box culvert and the state of the surrounding subway lines are monitored in real time and dynamically, and the jacking strategy is adjusted in a timely manner based on the early warning classification mechanism, significantly improving the safety and reliability of the construction process. Especially under the conditions of tight construction period and limited maintenance period, it is possible to quickly organize jacking operations, shorten the construction period, ensure the overall project progress, and effectively respond to the dual requirements of rail transit construction for timeliness and safety. The present invention integrates the installation of jacking equipment, counterweight arrangement, excavation operation and jacking construction module in a coordinated manner to form a standardized and modular operation system, which can be flexibly adjusted according to actual construction needs, adapt to different geological conditions and structural layouts, and significantly improve the adaptability and efficiency of jacking construction. The whole system is compactly configured, the equipment is conveniently debugged, and each process in the jacking operation is smoothly connected, which is conducive to forming a safe, green and efficient construction environment. The present invention not only effectively solves multiple technical problems such as crossing over a subway shield, tight construction period, counterweight control and cooperation with open cut jacking, but also realizes the all-round protection of the subway interval tunnel during construction, meets the high standards of quality, safety and environmental protection requirements, and has good popularization and application value. Especially in the field of jacking construction in complex urban rail transit intervals, it has important engineering demonstration significance and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a structural diagram of a box culvert jacking construction system for the upper cross-connection of urban rail transit sections provided by an embodiment of the present invention;Figure 2 is the construction process flow provided by the embodiments of the present invention; Figure 3 is a schematic diagram of an ingot provided by the embodiments of the present invention; Figure 4 is a schematic diagram of the placement of ingot counterweights provided by the embodiments of the present invention; Figure 5 is a schematic diagram of the transportation of ingot counterweights provided by the embodiments of the present invention; Figure 6 is an ingot counterweight block and a lifting tool provided by the embodiments of the present invention; Figure 7 is a schematic diagram of the placement of steel bar counterweights provided by the embodiments of the present invention; Figure 8 is a schematic diagram of a steel plate provided by the embodiments of the present invention; Figure 9 is a schematic diagram of the layout of jacking equipment provided by the embodiments of the present invention; In the figure: 1, counterweight setting and removal module; 2, jacking force calculation system; 3, jacking equipment and installation module; 4, jacking excavation module; 5, jacking construction module; 6, construction monitoring module. Specific embodiments

[0017] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] At the beginning of construction, the equipment execution module organizes the entry of machinery such as forklifts and crawler cranes, accurately hoists and stacks ingot counterweight blocks and steel plate counterweights at the positions of the precast culvert bottom slab and top slab according to the design drawings, and at the same time erects a disk buckle support frame system. All types of counterweight operations are constructed through special lifting pins and special channels to ensure uniform distribution of the counterweight load, enable the culvert to have the ability of empty jacking, and create necessary stable conditions for subsequent jacking operations.

[0019] Start the jacking force calculation system, input data such as self-weight, counterweight, friction coefficient, and earth pressure based on real-time monitoring parameters, and dynamically generate jacking force demand parameters. The hydraulic system synchronously completes the installation of components such as oil pumps, oil pipes, jacks, and control valves and the cleaning of the oil circuit, adjusts the relief valve through the pressure gauge, sets the standard jacking force output, and forms the first-round jacking force application configuration.

[0020] After the equipment is assembled, the control system commands to start the hydraulic oil pump, perform a low-pressure test run on the oil circuit and the jack, and monitor the pressure change in real time through the electric control box. The equipment gradually pressurizes to push the jack column to bear force. During the trial jacking process, observe the starting thrust, the deformation of the back beam, and the initial movement state of the culvert, and confirm that all hydraulic components and the jacking force transmission system are stable and reliable, providing mechanical guarantee for the formal jacking.

[0021] Two excavators are respectively positioned above the cross bracing beam and on the retaining wall platform, and excavate the soil in batches according to the instructions, with each advance not exceeding 0.4 meters, and precisely control the excavation depth and slope ratio. After each excavation is completed, immediately start the hydraulic jacking system to drive the jacks to synchronously push the culvert box forward, realizing continuous cyclic operation, maintaining the stability of the equipment, and avoiding the risks of bottom soil disturbance or over-excavation.

[0022] In the formal jacking stage, the hydraulic system coordinates the jacks to apply force in sequence in zones according to the preset rhythm. Combining with the force adjustment of the jack posts and the back beam, by comparing the axis and elevation deviations through real-time monitoring data, dynamically fine-tune the jacking force distribution to achieve direction correction and attitude control. The operators cooperate to replace the jacking irons and extend the jack posts to ensure the stable force transmission and construction safety of long-distance continuous jacking.

[0023] During the jacking process, the construction monitoring module and the third-party monitoring system synchronously and real-time feedback the data of the displacement in the subway protection area, the deformation of the culvert box, and the change of the jacking force. After the culvert box reaches the designed position, organize the mechanical equipment to remove the steel ingot and steel plate counterweights in stages in an orderly manner according to the monitored and confirmed structural stability state. At the same time, synchronously complete the earth backfilling and the construction of the culvert box joints, and smoothly transfer to the next step of the project.

[0024] As Figure 1 shown, the embodiment of the present invention provides a culvert box jacking construction system for the overcrossing connection of urban rail transit intervals. The system includes: a counterweight setting and removal module 1, including steel ingot counterweights, steel bar counterweights, and counterweight removal; a jacking force calculation system 2 for calculating the jacking force; a jacking equipment and installation module 3, including a hydraulic system, force transmission equipment, equipment installation and commissioning; a jacking excavation module 4 for jacking and excavating; a jacking construction module 5, including pre-jacking inspection, trial jacking, jacking and deviation correction measures; a construction monitoring module 6, including measurement and monitoring during the jacking process, existing subway monitoring, and monitoring and control of the box body during the culvert box jacking operation.

[0025] The steel ingot counterweight specifically includes: (1) Place steel ingot counterweight blocks with dimensions of 3m×1.5m×0.5m on the precast culvert box floor, with a single block counterweight of 17.5t, and a total of 144 blocks are configured, totaling 2520t; (2) Place two stacks of counterweight blocks horizontally in one row, with each stack stacked in three layers and placed longitudinally in 24 rows; The counterweight blocks are placed near the two side axils respectively, with a passage with a width of not less than 1.1m reserved in the middle; A spacing of about about 150mm is reserved between each row of counterweight blocks; (3) The precast culvert box is jacked forward empty on the slide plate for about 8 - 9m. Near the boundary of the key protection area, it is not allowed to enter the key protection area; The counterweight blocks are sent into the culvert box from the east entrance by a 20t forklift and stacked neatly row by row from west to east; (4) Build a ramp on the jack support and jacking equipment with steel plates and support frames, place a 20t forklift, configure a 300t crawler crane on the ground, and use the crawler crane for hoisting in cooperation with the forklift for transfer. The counterweight blocks are hoisted with a wire rope hung with a supporting special pin, and the forklift places the counterweight blocks at the designated positions in the culvert box.

[0026] The steel bar counterweight specifically includes: (1) Place steel plates with dimensions of 6m × 2.2m × 0.02m on the precast culvert top slab; a total of 1,200 sheets, each sheet weighing approximately 2.1t, with a total weight of approximately 2,520t; (2) Place the steel plates longitudinally in the east-west direction along the culvert top slab, with 50 sheets in each stack, arranged in 4 stacks side by side, and placed in 6 rows along the length of the culvert; (3) Before placing the steel plate counterweight, set up a 0.9m-wide socketed disc buckle support frame along the center line of the culvert interior for back support, with adjustable bases and adjustable brackets placed on the upper and lower parts respectively, and square timbers or steel channels padded inside the adjustable brackets.

[0027] The removal of the counterweight specifically includes: (1) After the culvert is jacked into place, seal and pour fluidized solidified soil at both ends of the gap between the retaining piles on both sides of the culvert; return the construction site of the plot, and the subsequent main foundation pit structure construction can be carried out on Plot 604; at the same time, excavate and construct the cast-in-place structures on both sides, first construct the cast-in-place structure connecting with Plot 605 on the west side, and then construct the cast-in-place structure connecting with Plot 604 on the east side; (2) After the cast-in-place structure construction of the connecting channel with Plot 605 is completed, backfill the soil above the top slab layer by layer according to the planned ground elevation. After the cast-in-place structure floor slab construction of the connecting channel with Plot 604 is completed and the strength reaches 80% of the design strength, in combination with the monitoring and measurement results, remove the steel ingot counterweight inside the culvert from the east side, keep the counterweight on the culvert top slab unchanged, and add emergency counterweights on the top slab within the range of the culvert side wall if necessary; (3) After the cast-in-place structure top slab construction of the connecting channel with Plot 604 is completed, gradually remove the steel plate counterweight on the top slab in combination with the monitoring and measurement results, and backfill the soil section by section; the length of each steel ingot removal shall not be greater than 3m, the steel plate counterweight is 6m long, and the steel plate counterweights in the same row can be removed in batches, and then backfill the soil and compact it immediately; place emergency steel ingot counterweight blocks if necessary.

[0028] The jacking force calculation specifically includes: , where K - take 1.2; N1 - the total load on the culvert top, here it is the weight of the placed counterweight, 5,242t; f1 - the friction coefficient between the upper surface of the culvert top and the load on the top, for open cut jacking, F1 = 0; N2 - the self-weight of the culvert, 2,622t; f2 - the friction coefficient between the culvert bottom slab and the foundation soil, take 0.7; E - the lateral earth pressure on both sides of the framed culvert (kN), with pile support on both sides, the fat groove can be cancelled, and the lateral pressure is not considered temporarily; f3 - the side friction coefficient, take 0.7; R - the frontal resistance of the cutting edge (kN / m 2 ); A - the frontal area of the cutting edge (m 2 ).

[0029] Furthermore, the jacking equipment and installation module specifically include: (1) a hydraulic system, which consists of a power mechanism, a high-pressure oil pump, a control mechanism such as an electro-hydraulic control valve, a regulating valve, an electric control box, a jack, and auxiliary devices such as an oil tank, oil pipes, hydraulic components, a pressure gauge, etc.; (2) a force transmission device, the reaction force is provided by a reinforced concrete reaction beam, and the dimensions of the reaction beam are: length 11.8 m, thickness 2.0 m, height 5.3 m; the force transmission devices of the jacking frame are steel backing plates with a thickness of 20 mm, jack posts, distribution crossbeams, and jack post crossbeams, etc., and the jack posts are fabricated by welding H-shaped steel; (3) equipment installation, each component such as the jack, high-pressure oil pump, electro-hydraulic control valve, electric control box, and various instruments of the hydraulic system shall be subjected to a single test after overhaul, and can be installed only after passing the test; the power mechanism, high-pressure oil pump, oil tank, control mechanism, and auxiliary devices are arranged on the top plate of the culvert box, and the supporting high-pressure oil pipes and distribution oil pipes are connected to the jacks; the inner diameter of the oil pipes of the hydraulic system is determined by the oil volume, but the inner diameter of the main oil pipe of the oil return pipeline shall not be less than 10 mm, and the inner diameter of the branch oil pipe shall not be less than 6 mm; the oil pipes shall be cleaned, the oil circuit shall be reasonably arranged, and the sealing shall be good, and the hydraulic grease shall be filtered; steel backing plates with a size of 10 m × 0.9 m and a thickness of 20 mm are padded on the side of the bottom plate of the culvert box, and 20 500-t jacks are arranged in sequence from the middle line to both sides for installation; a jack post is installed corresponding to each jack, and the jack post shall be consistent with the jacking force axis and perpendicular to the crossbeam and the back beam; steel backing plates with a size of 10 m × 0.9 m and a thickness of 20 mm are installed on the back wall, and a cross bracing beam is installed; when the jacking distance is long, a cross bracing beam is added every 4 m to 8 m; the jack posts and crossbeams for force transmission shall be prepared in accordance with the planned specifications and quantities and overhauled before installation; (4) commissioning, the purpose of the commissioning work is to comprehensively check whether the hydraulic components are reliable, whether there are any abnormalities in the functions of the jacks, whether the pipelines are leaking, adjust the acting pressure of the relief valve, and gradually increase the oil pressure to push the box body, measure the starting thrust, and check the changes of the back; after all the hydraulic systems are installed, connect the circuits for trial operation, check the oil circuit, control valves, jacks, oil pumps, circuits, control boxes, and supporting auxiliary equipment, etc., to make them operate normally; after the hydraulic system is debugged and operates normally, apply the jacking force to make the force transmission device bear the force, and carefully check the force transmission device to meet the requirements of jacking.

[0030] The jacking and excavation module 4 specifically includes: (1) For the jacking of the box culvert, mechanical excavation is adopted, and the soil is excavated step by step in the reverse direction of the jacking progress following the jacking step distance; two excavators are selected for the excavation operation. One 330-type excavator stands on the cross bracing beam for batch earth excavation, and one long-arm excavator stands on the platform outside the retaining wall to cooperate in cleaning the foundation base. When mechanically excavating, to prevent over-excavation and disturbing the original soil layer at the bottom, 20 cm of the foundation base soil is reserved for manual excavation. The excavator at the lower level excavates the soil to 1.5 m outside the retaining wall, and the loader cooperates with the dump truck to promptly transfer and transport the soil away, and no soil shall be piled on the platform. (2) Before jacking and excavation, first backfill the soil excavated from the cross bracing beam during construction. The backfill soil is higher than and covers the cross bracing beam by no less than 300 mm. The excavator at the lower level parks on the backfill soil layer for the excavation operation of the jacking foundation pit. (3) For the jacking of the box culvert, excavation is carried out first, and then jacking immediately. The excavation footage each time shall not be greater than 0.4 m. The front of the box culvert structure is excavated with a slope, and the slope ratio is 1:1. The excavation work shall maintain close contact with the three-party monitoring personnel, and appropriately control the excavation footage according to the monitoring results, soil conditions, and the jacking stroke of the jacks. (4) When jacking while eating soil, the excavation bottom surface is 8 - 10 cm higher than the bottom surface of the box body. If the soil is soft, the excavation bottom surface is appropriately raised. During excavation, it is necessary to ensure "four non-excavations", that is, do not excavate when starting the jacking, do not excavate when the equipment fails, do not excavate when there is no jacking for a long time, and do not excavate before shift handover. (5) The excavation operation shall be uniformly commanded by the on-site construction responsible person. Before each excavation, the on-site construction responsible person shall conduct a comprehensive inspection and confirmation, and the on-site quality responsible person shall monitor. It is not allowed to excavate ahead of schedule. The excavation work shall closely cooperate with the surveying personnel, and improve the excavation method at any time according to the direction and deviation of the box body jacking. (6) During excavation, it is strictly prohibited to randomly over-excavate or under-excavate. Excavation is carried out from top to bottom. It is strictly prohibited to dig from the lower part and to dig against the slope. Keep the surface smooth and jack while digging. (7) During the construction process, it is necessary to prevent soil collapse to ensure the safety of traffic and personnel. If a collapse occurs during excavation and affects traffic safety, quickly organize emergency repair and reinforcement.

[0031] The jacking construction module 5 specifically includes: (1) Inspection before jacking: Conduct a comprehensive inspection of the culvert structure before jacking. The waterproof layer and waterproof protective layer should be completed according to the design requirements. The concrete strength of the culvert structure and the top protective layer should reach the design strength requirements, and the strength report of the same-condition test blocks of the main structure concrete should be inspected; conduct a comprehensive inspection of the back beam before jacking. The construction of the back beam and steel inclined struts should comply with the design, and the concrete of the back beam should reach the design strength requirements; check whether the unconfined compressive strength of the soil after grouting reinforcement of the sleeve valve pipe meets the design requirements; all jacking equipment has been debugged and meets the requirements of jacking construction; all types of construction machinery are in place and have passed the acceptance; the installation and commissioning of the hydraulic system are all normal and meet the jacking requirements; the counterweights of the culvert bottom plate and top plate have been delivered or prepared according to the plan and meet the requirements of being placed in place in time after empty jacking; the on-site lighting installation is completed, and the lighting range and brightness should meet the construction requirements; the observation instruments, observation punctuation marks, and scales are installed, aligned with the reference points after calibration, and the initial readings should be measured; for excavation and jacking, the project management personnel conduct technical disclosure to the excavation and jacking personnel, clarify the working scopes and responsibilities of the earthwork unit and the jacking unit, stipulate the excavation method, the excavation progress each time, and the operation connection signals, and determine the liaison personnel on both sides; (2) Trial jacking: The trial jacking work generally ends when the box body is moved. Therefore, during the trial jacking, the observation of the center line, level, and longitudinal displacement of the box body should be strengthened, and at the same time, the changes in the back and bottom plates should also be noted; the trial jacking work is to operate all the jacks to jack out together. When the jacking block touches the back, the oil pressure gradually increases. When the starting resistance of the box body is overcome and the box body is jacked, the pressure drops rapidly. At this time, the highest pressure value on the pressure gauge, after conversion, is the starting thrust of the box body. Considering the pressure loss in the pipeline and overcoming the internal friction resistance of the jacks, the actual thrust is based on 0. of the thrust reflected by the pressure gauge.When the pressure is about 97, there should be special personnel responsible for each relevant part during the trial jacking, and pay attention to the changes at any time. After starting the pump, when the oil pressure rises by 5 - 10 MPa, the pump must be stopped to observe the construction environment around the culvert box and the measurement data, and deal with any abnormalities in a timely manner. When the piston of the jack starts to extend and the jacking column is tightened, the jacking should be immediately stopped. After checking that there are no abnormalities in each part, the pump can be restarted and the data recorded. After the trial jacking, a comprehensive inspection should be carried out again. If the conditions of each part are all good, the formal jacking operation can be carried out. (3) Jacking: It is required to reserve a working pit to ensure that the entire culvert box is precast in one piece to complete the full length. Therefore, the one-time jacking method is selected for the jacking construction. The jacking operation is divided into several stages: culvert box startup, empty jacking, excavation and jacking, jacking in place, and removal of jacking equipment. Once the jacking operation starts, it should be continuously constructed, and close coordination should be carried out among each process. Before jacking, a plan for the arrangement and combination of jacking columns should be formulated, and jacking columns of different specifications and sizes should be arranged and combined. When the culvert box is jacked empty on the working pit slide plate, special attention should be paid to the axial direction of the culvert box. The jacking forces on both sides of the axis should be adjusted in a timely manner according to the deviation to make the culvert box enter the soil along the designed axis direction. When lateral deformation of the line is found during jacking, the jacking should be immediately stopped and corrected in a timely manner. After the front section of the culvert box starts to take soil, the speed of excavation and soil removal should be accelerated, and continuous operation should be carried out day and night to keep the culvert box continuously jacking. After entering the bottom layer grouted and reinforced by the sleeve valve pipe, the excavation advance per time shall not be greater than 0.4 m. Before each jacking, the hydraulic system, force transmission equipment, cutting edge, backrest, slide plate, etc. should be checked for changes, and problems should be dealt with in a timely manner. When the culvert box starts, special personnel should observe each part and observation points. After starting the pump, the pressure should be increased in stages. When the oil pressure rises by 5 MPa - 10 MPa each time, the pump should be stopped for inspection once, and any abnormalities should be dealt with in a timely manner. During jacking, it is strictly prohibited to stand people near the jacking columns, cross beams, etc. and the backrest. Observe the stress condition of the jacking columns in the safety area to prevent accidents caused by the jacking columns arching and bursting out. The jacking of the culvert box and the excavation and transportation of soil should be carried out alternately in a cycle, and excavation operations should be started in a timely manner according to the connection signal during the process of replacing the jacking iron, and should be completed as much as possible at the same time, and the working surface should not be excavated in advance and wait for the jacking. For each advance of one jacking stroke, different specifications of jacking iron and jacking columns should be replaced and connected according to the jacking length, straightened in the axial direction, and should be perpendicular to the cross beam and the backrest. The contact surface should be wedged tightly with steel plates. To prevent possible instability after the jacking columns are lengthened, fill the soil on the jacking columns and compact it or place counterweight blocks. For each advance of one jacking stroke of the culvert box, the axis and elevation should be observed, and any deviation should be corrected in a timely manner. Before the handover of each shift, the jacks, oil pump hydraulic system, jacking columns, backrest, platform and other equipment should be carefully checked to keep the equipment in good condition. Records should be made during the jacking process and handed over with the shift. During jacking, the observers should record the advance per jacking stroke, the deviation of the axis and elevation, the number of jacks opened, the oil pump pressure, the instantaneous jacking force, etc., and should notify the on-site commanders in a timely manner with a report form of the jacking deviation to take measures to correct it. The stop time during jacking should not exceed 2 h.

[0032] The construction monitoring module 6 specifically includes: (1) measurement and monitoring during the jacking process: the observation instrument for monitoring the jacking process of the box culvert is set outside the back force influence area, and rainproof lighting facilities are set at the same time; during the jacking construction, full-time measurement personnel continuously observe, record, analyze and control the various parts of the box culvert, the jacking system and the back; when the box culvert is found to be deformed or displaced, the technical person in charge is immediately reported to analyze the cause and make corresponding adjustments to the jacking system to ensure the safety of the jacking construction; during the jacking process, the box culvert axis, elevation and box culvert structure deformation are continuously monitored; the deformation and lateral stability of the jacking column (jacking iron) axis direction are kept under observation, and the deformation near the contact beam support point is observed to ensure the safety of the jacking construction. Ensure that the force transmission structure system works normally; observe the back deformation and cracks in the soil in the force-affected area; maintain close contact with the third-party monitoring unit to understand and grasp the monitoring data of the subway line 6, roadbed and line isolation piles in real time to ensure the smooth implementation of the jacking work; (2) Monitoring precautions: Monitoring information should be fed back in a timely manner, and a good communication and data exchange mechanism should be established with the monitoring unit; before starting work, the current status of surrounding buildings and pipelines should be investigated, and monitoring should be strengthened during construction. Cracks and settlements in buildings and pipelines, as well as corresponding construction conditions and measures taken, should be recorded accordingly; monitoring should be based on special instrument measurements or special test components to obtain quantitative data, with on-site inspection as the main method. The time intervals for various monitoring tasks shall be determined according to the progress of construction. In places where the stress changes are complex or when abnormal conditions occur, the monitoring shall be intensified. All measuring points shall reflect the changes in stress or deformation of the measuring points over time during construction, that is, from the start of construction to completion and until the observation data tends to be stable. Monitoring and measurement control standards shall be formulated for monitoring projects according to the principle of "zoning, grading and phasing", and feedback and control shall be carried out according to the three-level warnings of yellow, orange and red. In the monitoring work, the monitoring team shall work closely with relevant units and personnel, and shall ensure the rationality of the monitoring plan, the authenticity of the monitoring data, the stability and reliability of the measuring points and instruments, the timeliness of data processing and feedback, and the monitoring cycle. Integrity; monitoring results should be fed back to the construction unit, design unit and supervision unit in a timely manner; (3) Existing subway monitoring: entrust a qualified third-party monitoring unit to be responsible, strengthen communication and contact with the monitoring unit during the construction process, receive feedback information in a timely manner, and actively cooperate with the construction unit, operating company and monitoring unit to prepare response measures for various emergencies to ensure construction safety; (4) Box culvert box body monitoring and control during jacking operation: From the start of jacking to the empty jacking stage before the box culvert enters the soil, the guide rail is mainly used to control the direction of the steel rail placed between the guide pier and the box culvert; during the jacking process, the horizontal deviation and directional deviation of the box culvert and the deformation of the back should be monitored. If there is any deviation, measures should be taken to correct it in time.

[0033] An embodiment of the present invention provides a box culvert jacking construction method for urban rail transit interval overcrossing connection based on the box culvert jacking construction system for urban rail transit interval overcrossing connection, characterized in that the method specifically includes: S1: Using the counterweight setting and removal module to conduct ingot counterweight, steel bar counterweight, and counterweight removal; S2: Using the jacking force calculation system to calculate the jacking force; S3: Using the jacking equipment and installation module to install and debug relevant hydraulic systems and force transmission equipment; S4: Using the jacking excavation module to conduct jacking excavation; S5: Using the jacking construction module to conduct inspections before jacking, trial jacking, jacking, and deviation correction measures; S6: Using the construction monitoring module to conduct measurement monitoring during jacking, monitoring of existing subways, and monitoring and control of the box body during box culvert jacking operations.

[0034] The effects of the present invention in practical applications.

[0035]

[0036] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be covered by the protection scope of the present invention.

Claims

1. A construction method for jacking box culverts for overcrossing connection in the section of urban rail transit, characterized in that, It includes the following steps: S1. Counterweight setting and removal step: Use a forklift and a crawler crane to arrange the ingot counterweight and steel plate counterweight at the positions of the culvert bottom slab and top slab respectively, and set up a socketed support frame to complete the application of the counterweight; S2. Jacking force calculation and hydraulic system configuration step: Use a jacking force calculation system to calculate the thrust required for culvert jacking, and complete the installation and commissioning of equipment such as the hydraulic system, jacks, and oil pumps according to the calculation results; S3. Jacking excavation and synchronous propulsion step: Use an excavator to excavate the soil in batches and reserve the foundation bottom, and cooperate with the hydraulic jacking equipment to synchronously push the culvert forward section by section, controlling the excavation and jacking step distance each time; S4. Construction monitoring and counterweight removal step: Based on the measurement and monitoring system, monitor the axis, elevation, and structural deformation during the culvert jacking process in real time. After the jacking is in place, remove the counterweight in stages according to the monitoring data instructions and complete the backfilling operation.

2. The construction method according to claim 1, characterized in that: In the counterweight setting step, the ingot counterweight blocks are hoisted by hanging the steel wire rope with special pins, and are stacked row by row by a 20t forklift on both sides of the armpit area of the culvert bottom slab, leaving a passage in the middle. And the steel plates are stacked side by side along the long direction on the culvert top slab, and are supported by a 0.9-meter-wide disc buckle support frame.

3. The construction method according to claim 1, characterized in that: In the jacking excavation and synchronous propulsion step, two excavators are used for cooperative operation. A 330-type excavator excavates in batches, and a long-arm excavator cleans the foundation bottom. Manually excavate and reserve 20cm of foundation soil at the bottom. The single jacking step distance does not exceed 0.4m, and the excavation bottom elevation is adjusted in real time during the soil-eating jacking stage.

4. The construction method according to claim 1, wherein In the construction monitoring and counterweight removal step, the monitoring information sets three-level early warnings of yellow, orange, and red according to the principles of "zoning, grading, and staging". After the jacking is completed, control the backfilling rhythm according to the method of removing the ingot counterweight and steel plate counterweight section by section. The length removed each time shall not be greater than 3m to ensure the structural stability of the culvert.

5. A box culvert jacking construction system for urban rail transit section overpass connection, characterized in that: It includes: A counterweight setting and removal module for arranging the ingot counterweight and steel plate counterweight on the culvert bottom slab and top slab, and removing the counterweight in stages after the jacking is completed; A jacking force calculation system for calculating the required jacking force according to parameters such as counterweight, self-weight, and friction resistance and outputting hydraulic system configuration instructions; A jacking equipment and installation module, including a hydraulic system, a force transmission device, and related installation and commissioning devices, for providing jacking power and realizing the overall propulsion of the culvert; A jacking excavation module for synchronously coordinating the excavation equipment to carry out step-by-step excavation and controlling the matching of the excavation footage and jacking process each time; A jacking construction module for performing pre-jacking inspections, trial jacking, jacking operations, and deviation correction measures; A construction monitoring module for real-time monitoring of the culvert axis, elevation deformation, and the stability of the subway line, and adjusting the construction parameters according to the monitoring data.

6. The box culvert jacking construction system according to claim 1, characterized in that, The counterweight setting and removal module includes a forklift, a crawler crane, a special lifting fixture, and a disc buckle support frame. A passage is reserved for stacking the counterweight blocks, and the counterweight blocks and steel plates are respectively arranged in zones according to the positions of the culvert bottom slab and top slab.

7. The box culvert jacking construction system according to claim 1, characterized in that, The hydraulic system in the jacking equipment and installation module includes a power mechanism, a high-pressure oil pump, an electro-hydraulic control valve, a jack, an oil pipe, a pressure gauge, and an electric control box, and transmits the jacking thrust through the partitioned arrangement of the jack columns and the back beam.

8. The box culvert jacking construction system according to claim 1, wherein, The construction monitoring module includes a measurement and monitoring subsystem, a subway protection monitoring subsystem, and a culvert deformation control subsystem. It sets up partition measurement points, implements phased and graded monitoring and early warning, and automatically links and adjusts the jacking operation parameters in case of anomalies.

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