Pipe jacking construction method and process

Abstract

The application relates to the technical field of pipe jacking construction, in particular to a pipe jacking construction method and process, which comprises the following steps: S1, topography and control network establishment, the traverse network and the leveling network and the control points provided by a construction unit are re-measured, and the accuracy of 1mm is ensured. The application ensures careful preparation before construction through topographic survey and control point re-checking, and improves construction accuracy and efficiency. The re-checked control point data and the establishment of the precise control network guarantee accurate alignment and orientation during the construction process, reduce the possibility of error occurrence, and reduce the influence on the surrounding environment. The use of a total station and a level instrument for lofting guarantees the consistency of the design coordinates and the actual positions of the shaft and the pipeline, and improves the reliability of the construction. In addition, accurate pipe jacking machine installation and debugging, as well as calculation and checking of the jacking force parameters, ensure construction safety and the smoothness of the jacking process. These measures not only improve the construction quality, but also effectively reduce the risk.

Description

Technical Field

[0001] This invention relates to the field of pipe jacking construction technology, and in particular to a pipe jacking construction method and process. Background Technology

[0002] Pipe jacking is used in urban infrastructure construction, such as water supply, drainage, cables, and gas pipelines. This technology uses specialized pipe jacking equipment to advance pipelines underground without excavation, thus minimizing the impact on urban traffic and the environment. Pipe jacking not only reduces environmental disturbance and public inconvenience during construction but also effectively lowers construction costs and provides a safe and reliable pipeline laying solution in certain complex geological conditions. This technology is particularly suitable for areas with heavy traffic or where it is necessary to protect surface buildings and natural landscapes.

[0003] However, existing technologies have limited capabilities in real-time monitoring and adjustment of the jacking direction, which is particularly evident in complex geological conditions, potentially leading to construction accidents and delays, and impacting construction efficiency. These technical and operational shortcomings limit the effectiveness and safety of pipe jacking technology in a wider range of or more challenging environments. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a pipe jacking construction method and process.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a pipe jacking construction process, comprising the following steps:

[0006] S1. Establishment of topography and control network: Re-survey the traverse network, leveling network and control points provided by the construction unit to ensure an accuracy of ±1mm. The surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points. After completion, certified control point data is generated, and a plane control network and an elevation control network are established. In addition, a third-order traverse plane control network is set up around the jacking shaft. The fourth-order leveling method is used to form a closed traverse network with the closure error controlled within 12mm.

[0007] S2: Installation of the guide rail system and adjustment of the pipe jacking machine equipment. Based on certified control point data, the center of the shaft and the center line of the pipe jacking are laid out to ensure that the laying out error is within ±3mm. Control points are set up at the bottom of the shaft and the control information is transmitted to the bottom of the shaft to ensure that the elevation transmission accuracy is within ±3mm. When installing the guide rail system, ensure that the guide rail is straight, parallel and at the same height, and the axis position deviation is controlled within 3mm. The top surface elevation and track gauge deviation are both within the strict control range. After installation, the guide rail system with the required accuracy is used for the installation of the pipe jacking machine to ensure that the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder, and that the machine position is accurate.

[0008] S3, Pipe jacking operation and monitoring: Install and debug the circuit, oil circuit and mud system of the pipe jacking machine that has been put in place; check the standard value of total jacking force and the thrust of the pipe jacking machine and the main jacking cylinder; chisel and clean the wall of the tunnel opening to ensure that the size of the tunnel opening can accommodate the pipe jacking machine head; after the pipe jacking machine head successfully enters the tunnel, control the jacking direction and maintain the stability of the direction through correction adjustment.

[0009] S4. Optimize construction parameters and strengthen the structure. Measure and control earth pressure and slurry parameters. Calculate the earth pressure control value at the excavation face based on groundwater pressure and earth pressure. Adjust the slurry specific gravity and flow rate to ensure the stability of the excavation face and reduce surface settlement. The construction of the pipe jacking test section verifies the relationship between jacking speed, slurry parameters, and surface settlement, thereby optimizing construction parameters and carrying out normal tunneling. Control the jacking speed and slurry specific gravity, regularly measure the pipeline axis and elevation, and correct errors. Finally, prepare for the exit operation of the pipe jacking machine head. Reinforce the soil in front of the receiving shaft opening in advance to ensure the machine head smoothly enters the receiving shaft, resulting in a successfully exiting pipe jacking machine head.

[0010] Preferably, S1 includes:

[0011] S101, Conduct topographic surveying and control point verification of the construction area. Use instruments to re-measure the traverse network and leveling network and their control points provided by the construction unit. The instruments include total station, precision level and GPS surveying equipment, with an accuracy within ±1mm. The surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points, and densifying the control points as needed. After the survey is completed, the verified control point data is obtained.

[0012] S102, establish a plane control network and an elevation control network based on the verified control point data; set up a third-order traverse plane control network near the jacking shaft to form a closed traverse network; use fourth-order leveling method for elevation control, use a precision level, and control the closure error within 12mm; thus obtaining a construction control network that meets the accuracy requirements.

[0013] S103, based on the construction control network that meets the accuracy requirements, lay out the center of the shaft and the center line of the jacking pipe; using a total station and a level, accurately transfer the design coordinates and elevations of the shaft and pipe to the construction site, with the layout error controlled within ±3mm; after layout, set up markers and take protective measures to obtain the axis and elevation control markers of the construction site;

[0014] S104, the axis and elevation control marks of the construction site are transferred to the bottom of the shaft; the elevation and coordinates are transferred from the ground to the bottom of the shaft using the suspended steel tape method, and two level instruments are used for synchronous observation to ensure that the elevation transfer accuracy is within ±3mm; the control points at the bottom of the shaft are set up to obtain the construction control points at the bottom of the shaft;

[0015] S105, at the construction control point at the bottom of the shaft, install a guide rail system. During installation, ensure that the two guide rails are straight, parallel, and at the same height, and that the longitudinal slope is consistent with the design slope of the pipeline. The guide rails are made of I63a I-beams, 24a and 22a channel steel, and are 5-10 meters long. The axial position deviation of the guide rails shall not exceed 3mm, the top surface elevation deviation shall be controlled within ±3mm, and the track gauge deviation shall be controlled within ±2mm. After installation, a guide rail system with the required accuracy is obtained.

[0016] Preferably, S2 includes:

[0017] S201, Use the guide rail system with the required accuracy for the installation of the pipe jacking machine; Use a hoisting device with a lifting capacity of 300-350 tons to place the slurry balance pipe jacking machine weighing 60-70 tons on the guide rail, with the front end of the pipe jacking machine 0.3-0.5 meters away from the shaft wall; After installation, check whether the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder to obtain the accurately positioned pipe jacking machine equipment;

[0018] S202, Install and debug the electrical circuit, oil circuit and mud system of the accurately positioned pipe jacking machine; connect the main jacking cylinder, oil pump power station, mud inlet and outlet pipes and thixotropic mud system, and install monitoring instruments; after debugging, a fully functional pipe jacking machine system is obtained.

[0019] S203. Based on the fully functional pipe jacking machine system, perform jacking force calculation and verification; calculate the standard value of total jacking force according to the pipe outer diameter, jacking length, overburden thickness and soil parameters, and the result should be within the range of 8000-10000 kN; verify the thrust capacity of the pipe jacking machine and the main jacking cylinder to ensure that the jacking requirements are met and obtain jacking force parameters that meet the construction requirements;

[0020] S204, use the jacking force parameters that meet the construction requirements to verify the bearing capacity of the back structure of the working pit; calculate the maximum jacking force that the back wall can withstand based on the back wall size, earth pressure, passive earth pressure and safety factor, which should be in the range of 15000-18000 kN; verify that the back structure meets the stability and strength requirements, and carry out reinforcement design if necessary to obtain a back structure scheme that meets the bearing requirements;

[0021] S205, under the guidance of the back structure scheme that meets the load-bearing requirements, the opening and the stratum are reinforced; the anchor sprayed concrete and grid support at the opening of the vertical shaft are removed, and a reinforced steel grid and vertical steel bars are installed to form a reinforced ring beam for the opening; the soil within 5-10 meters in front of the opening is reinforced by deep hole grouting, and the unconfined compressive strength is increased to 1.0-1.5 MPa, so as to obtain a stable opening and a reinforced stratum in front.

[0022] Preferably, S3 includes:

[0023] S301, carry out the chiseling and cleaning of the opening wall; use a pneumatic hammer and cutting machine to chisel away the wall at the opening, thoroughly remove the steel bars and concrete residue, and ensure that the opening size meets the requirements for the pipe jacking machine head to enter; after cleaning, the opening wall is cleaned.

[0024] S302, the cleaned tunnel wall is used for the entry and advancement of the pipe jacking machine head; the pipe jacking machine is started, and the advancing speed is controlled within the range of 5-10 mm per minute. The machine head smoothly enters the tunnel, and the position of the water-stop ring is adjusted to completely seal the groundwater; by monitoring the tilt angle and rotation angle of the machine head, timely correction and adjustment are made to obtain a successfully entered pipe jacking machine head.

[0025] S303, control the initial jacking direction of the jacking head that has successfully entered the tunnel; rigidly connect the first section of concrete pipe to the jacking head with multiple bolts to ensure the firmness of the connection; use the correction cylinder and the weight of the jacking head to adjust the tilt angle and offset of the jacking head to maintain the stability of the jacking direction and obtain a jacking head with directional correction.

[0026] S304, under the guidance of the jacking head with the corrected direction, the pipe jacking and correction operation begins. A measurement is taken every 250-300 mm of advance, and the deviation is controlled within ±20 mm. The axis and elevation of the jacking machine are monitored in real time using a laser guide. The attitude of the jacking machine is adjusted by controlling the correction cylinder to obtain a stable jacking process.

[0027] S305, the soil pressure and slurry parameters are measured and controlled during the stable pipe jacking process; the soil pressure control value at the excavation face is calculated based on the groundwater pressure and soil pressure, and the pressure in the slurry chamber is kept within the calculation range; the slurry specific gravity and flow rate are adjusted to ensure the stability of the excavation face, reduce surface settlement, and obtain controlled soil pressure and slurry parameters at the excavation face.

[0028] Preferably, S4 includes:

[0029] S401, the controlled excavation face earth pressure and slurry parameters are used for the construction of the pipe jacking test section; the entire pipe jacking section is used as the test section, and soil settlement monitoring points are buried at a depth of 1.0-2.0 meters above the top of the pipe; the relationship between jacking speed, slurry parameters and surface settlement is verified through the test section, and the construction parameters are optimized to obtain the optimized jacking construction parameters;

[0030] S402, under the guidance of the optimized jacking construction parameters, normal tunneling is carried out; the jacking speed is controlled within the range of 10-20 mm per minute, the mud specific gravity is between 1.10-1.25, and the flow rates of mud delivery water and mud discharge water are kept in balance; the pipeline axis and elevation are measured regularly, and the deviation is controlled within ±10 mm to obtain a continuous and stable tunneling process;

[0031] S403, implement drag reduction measures for the continuous and stable tunneling process; uniformly apply industrial paraffin wax with a thickness of 1-2 mm to the outer wall of each pipe section to improve the sliding properties of the pipe wall; simultaneously carry out thixotropic mud injection operation, with the mud viscosity controlled within the range of 20-25 seconds and the injection pressure between 0.1-0.2 MPa, to obtain a jacking environment with reduced frictional resistance;

[0032] S404, the jacking environment with reduced frictional resistance is used for secondary waterproofing of the pipeline; a non-woven fabric with a thickness of 2-5 mm is wrapped around the outside of the rubber ring of the pipeline interface, and an oil-hemp filler is added; after jacking, the pipeline joint is treated with oil-hemp to obtain a pipeline interface with enhanced sealing performance.

[0033] S405, For the pipe interface with enhanced sealing performance, prepare for the exit operation of the pipe jacking machine head; According to the progress of pipe jacking, perform double-liquid grouting reinforcement on the soil in front of the receiving well opening for a length of 5-10 meters in advance, and control the grouting pressure between 0.2-0.5 MPa to improve the soil strength and obtain the reinforced soil in front of the opening.

[0034] S406, under the soil conditions in front of the reinforced tunnel entrance, the pipe jacking head is advanced out of the tunnel; the jacking speed is controlled, with the speed range between 5 and 10 millimeters per minute, to ensure that the head enters the receiving well smoothly; before exiting the tunnel, the receiving well wall is removed using a breaker hammer and cutting equipment, the pipe outlet position is located, and the successfully exited pipe jacking head is obtained.

[0035] Preferably, it also includes: S5, dismantling and hoisting the successfully exited pipe jacking head; using hoisting equipment with a lifting capacity of 300-350 tons, hoisting the pipe jacking head from the receiving shaft to the ground, and obtaining the safely dismantled pipe jacking head.

[0036] Preferably, it also includes: S6, after the pipe jacking head is safely dismantled, the pipeline is slurry replaced; cement and fly ash are mixed in proportion to prepare slurry, and grout is injected through the grouting holes inside the pipeline. The grouting is performed no less than three times, with an interval of no more than 24 hours, and the grouting pressure is controlled between 0.2-0.5 MPa, so as to obtain a pipeline with slurry replacement completed.

[0037] Preferably, it also includes: S7, conducting a water tightness test on the pipeline after the mud replacement is completed; observing the amount of water seepage within the pipeline over 24 hours by recording the amount of water seepage inside the pipeline to determine the sealing performance of the pipeline; and treating local seepage points with chemical grouting to ensure that the amount of water seepage is within the allowable range of the specification, thereby obtaining a pipeline project that meets the sealing requirements.

[0038] Preferably, in step S102, the side length of the conductor is controlled within the range of 50-100 meters.

[0039] This invention also discloses a pipe jacking construction method, including the following steps:

[0040] Accurately establish the terrain and control network, re-measure the traverse network and leveling network, and ensure an accuracy of ±1mm. Establish the plane and elevation control network. Then, lay out the center line of the shaft and the pipe jacking pipeline. At the same time, set up control points at the bottom of the shaft and install the guide rail system. The installation of the pipe jacking machine must ensure that its axis is aligned with the axis of the guide rail and the main jacking cylinder.

[0041] The installation and commissioning of the pipe jacking machine, including the electrical circuit, oil circuit and mud system, are carried out to ensure that the machine functions properly. The thrust is checked by the standard value of the jacking force to ensure that it meets the jacking requirements. After the pipe jacking machine successfully enters the tunnel, its jacking direction is controlled and corrected to maintain the stability of the jacking direction.

[0042] The soil pressure and slurry parameters at the excavation face are controlled, construction parameters are optimized, and deviations are corrected by regularly monitoring the pipeline axis and elevation. Before the pipe jacking machine head exits the tunnel, the soil in front of the receiving well is reinforced. After the machine head successfully enters the receiving well, the entire pipe jacking construction process is completed.

[0043] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0044] This invention ensures meticulous preparation before construction through topographic surveying and control point verification, improving construction accuracy and efficiency. The verified control point data and the establishment of a precise control network guarantee accurate alignment and guidance during construction, reducing the possibility of errors and minimizing the impact on the surrounding environment. The use of total stations and levels for layout ensures consistency between the design coordinates and actual locations of shafts and pipelines, enhancing construction reliability. Furthermore, precise installation and commissioning of the pipe jacking machine, as well as the calculation and verification of jacking force parameters, ensure construction safety and a smooth jacking process. These measures not only improve construction quality but also effectively reduce risks, optimize resource allocation, and reduce costs. Overall, they enhance the systematic nature and predictability of the construction, making the entire pipe jacking construction process more efficient and safer. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of steps S101-S302 in this invention;

[0046] Figure 2 This is a schematic diagram of steps S303-S7 in this invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0048] Firstly, please refer to Figure 1-2 This invention provides a technical solution, a pipe jacking construction process, comprising the following steps:

[0049] S1. Establishment of topography and control network: Re-survey the traverse network, leveling network and control points provided by the construction unit to ensure an accuracy of ±1mm. The surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points. After completion, certified control point data is generated, and a plane control network and an elevation control network are established. In addition, a third-order traverse plane control network is set up around the jacking shaft. The fourth-order leveling method is used to form a closed traverse network with the closure error controlled within 12mm.

[0050] S2: Installation of the guide rail system and adjustment of the pipe jacking machine equipment. Based on certified control point data, the center of the shaft and the center line of the pipe jacking are laid out to ensure that the laying out error is within ±3mm. Control points are set up at the bottom of the shaft and the control information is transmitted to the bottom of the shaft to ensure that the elevation transmission accuracy is within ±3mm. When installing the guide rail system, ensure that the guide rail is straight, parallel and at the same height, and the axis position deviation is controlled within 3mm. The top surface elevation and track gauge deviation are both within the strict control range. After installation, the guide rail system with the required accuracy is used for the installation of the pipe jacking machine to ensure that the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder, and that the machine position is accurate.

[0051] S3, Pipe jacking operation and monitoring: Install and debug the circuit, oil circuit and mud system of the pipe jacking machine that has been put in place; check the standard value of total jacking force and the thrust of the pipe jacking machine and the main jacking cylinder; chisel and clean the wall of the tunnel opening to ensure that the size of the tunnel opening can accommodate the pipe jacking machine head; after the pipe jacking machine head successfully enters the tunnel, control the jacking direction and maintain the stability of the direction through correction adjustment.

[0052] S4. Optimize construction parameters and strengthen the structure. Measure and control earth pressure and slurry parameters. Calculate the earth pressure control value at the excavation face based on groundwater pressure and earth pressure. Adjust the slurry specific gravity and flow rate to ensure the stability of the excavation face and reduce surface settlement. The construction of the pipe jacking test section verifies the relationship between jacking speed, slurry parameters, and surface settlement, thereby optimizing construction parameters and carrying out normal tunneling. Control the jacking speed and slurry specific gravity, regularly measure the pipeline axis and elevation, and correct errors. Finally, prepare for the exit operation of the pipe jacking machine head. Reinforce the soil in front of the receiving shaft opening in advance to ensure the machine head smoothly enters the receiving shaft, resulting in a successfully exiting pipe jacking machine head.

[0053] In this embodiment, S1 includes:

[0054] S101, Conduct topographic surveying and control point verification of the construction area. Use instruments to re-measure the traverse network and leveling network and their control points provided by the construction unit. The instruments include total station, precision level and GPS surveying equipment, with an accuracy within ±1mm. The surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points, and densifying the control points as needed. After the survey is completed, the verified control point data is obtained.

[0055] S102. Based on the verified control point data, establish a plane control network and an elevation control network; lay out a third-order traverse plane control network near the jacking shaft to form a closed traverse network; for elevation control, adopt the fourth-order leveling method, use a precision level, and control the closure error within 12mm; thus obtaining a construction control network that meets the accuracy requirements.

[0056] S103, based on the construction control network that meets the accuracy requirements, lay out the center of the shaft and the center line of the jacking pipe; using a total station and a level, accurately transfer the design coordinates and elevations of the shaft and pipe to the construction site, with the layout error controlled within ±3mm; after layout, set up markers and take protective measures to obtain the axis and elevation control markers of the construction site;

[0057] S104, the axis and elevation control marks of the construction site are transferred to the bottom of the shaft; the elevation and coordinates are transferred from the ground to the bottom of the shaft using the suspended steel tape method, and two level instruments are used for simultaneous observation to ensure that the elevation transfer accuracy is within ±3mm; the control points at the bottom of the shaft are set up to obtain the construction control points at the bottom of the shaft;

[0058] In step S101, the construction team conducted topographic surveys and control point verification of the construction area. The methods included using total stations, precision levels, and GPS surveying equipment to re-measure the traverse network and leveling network and their control points provided by the construction unit, ensuring an error within ±1mm. First, surveyors checked the location, elevation, and coordinates of existing traverse and leveling points to ensure the accuracy of this basic data. Next, as needed for construction, the surveying team densified the control points at necessary locations. This process was conducted using total stations, precision levels, and GPS surveying equipment to ensure accurate alignment for subsequent construction. After the surveying was completed, the construction team obtained a set of rigorously verified control point data. This data will be used to guide subsequent construction activities, ensuring the accuracy of the construction location and providing the necessary foundation for the next stage of control network construction.

[0059] In step S102, a plane control network and an elevation control network were established based on verified control point data. The construction team deployed a third-order traverse plane control network near the jacking shaft, ensuring a closed traverse network to enhance the stability and accuracy of the overall measurement. For elevation control, a fourth-order leveling method was employed, using a level instrument and strictly controlling the closure error to within 12mm. Through these steps, the construction team obtained a construction control network that met the accuracy requirements. The establishment of this control network ensured that the position and elevation of the shaft and pipe jacking accurately matched the design parameters, thereby guaranteeing the quality and safety of the construction.

[0060] In step S103, the work of setting out the center lines of the shaft and the jacking pipeline was carried out precisely. The construction team used a total station and a level to accurately transfer the design coordinates and elevations of the shaft and pipeline to the construction site. The setting-out error was strictly controlled within ±3mm. After the setting-out was completed, markers were set up on the construction site and protective measures were taken to ensure that the axis and elevation control markers were not disturbed during construction. Through these operations, the axis and elevation control markers on the construction site provided accurate references for subsequent construction activities, ensuring the efficiency and accuracy of the construction activities.

[0061] In step S104, the axis lines and elevation control markers at the construction site were accurately transferred to the bottom of the shaft. The construction team used a suspended steel tape method to transfer the elevation and coordinates from the ground to the bottom of the shaft, and used two levels for simultaneous observation to ensure that the accuracy of the elevation transfer was controlled within ±3mm. After completing these steps, the construction control points were precisely set at the bottom of the shaft. The successful execution of this process provided precise elevation and coordinate control points for the construction at the bottom of the shaft, ensuring the accuracy and efficiency of the construction.

[0062] S105. At the construction control point at the bottom of the shaft, install the guide rail system. During installation, ensure that the two guide rails are straight, parallel, and at the same height, and that the longitudinal slope is consistent with the design slope of the pipeline. The guide rails are made of I63a I-beams, 24a and 22a channel steel, and are 5-10 meters long. The axial position deviation of the guide rails shall not exceed 3mm, the top surface elevation deviation shall be controlled within ±3mm, and the track gauge deviation shall be controlled within ±2mm. After installation, a guide rail system with the required accuracy is obtained.

[0063] The construction team installed the guide rail system at the construction control points at the bottom of the shaft. The key to guide rail installation was ensuring the straightness, parallelism, and equal height of the two guide rails, while maintaining the same longitudinal slope as the designed pipe slope. To achieve these requirements, precision measuring tools were used to ensure that the guide rail's axial position deviation did not exceed 3mm, the top surface elevation deviation was controlled within ±3mm, and the track gauge deviation was controlled within ±2mm. During installation, the construction team used a laser measuring instrument and a level to continuously inspect the guide rails, ensuring all parameters met design requirements. After the guide rail system was installed, a guide rail system with strictly required precision was obtained. The accurate installation of this system was crucial for the smooth progress of the pipe jacking construction, ensuring the precise guidance and advancement of the pipe jacking machine.

[0064] In this embodiment, S2 includes:

[0065] S201. Use a guide rail system with the required precision for the installation of the pipe jacking machine; use a hoisting device with a lifting capacity of 300-350 tons to place the slurry balance pipe jacking machine weighing 60-70 tons on the guide rail, with the front end of the pipe jacking machine 0.3-0.5 meters away from the shaft wall; after installation, check whether the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder to obtain a pipe jacking machine with accurate positioning;

[0066] A guide rail system meeting the required precision was used for the installation of the pipe jacking machine. The construction team used lifting equipment with a lifting capacity of 300-350 tons to place the 60-70 ton slurry-balanced pipe jacking machine onto the guide rails, ensuring the distance between the front end of the pipe jacking machine and the shaft wall was controlled between 0.3-0.5 meters. After installation, the team checked the alignment of the pipe jacking machine's axis with the axes of the guide rails and the main jacking cylinder. This check was performed using a laser alignment instrument and a level to ensure all alignments met design standards. The accurate completion of this step ensured the stability and propulsion accuracy of the pipe jacking machine during construction, which is crucial for the success of subsequent jacking operations.

[0067] S202 involves installing and debugging the electrical circuits, hydraulic circuits, and mud system of the accurately positioned pipe jacking machine; connecting the main jacking cylinder, oil pump power station, mud inlet and outlet pipes, and thixotropic mud system; and installing monitoring instruments. After debugging, a fully functional pipe jacking machine system is obtained.

[0068] The electrical, hydraulic, and mud systems of the accurately positioned pipe jacking machine were installed and commissioned. The construction team connected the main jacking cylinder, oil pump power station, mud inlet and outlet pipes, and thixotropic mud system, and installed monitoring instruments. During the connection and installation process, technicians used various testing and diagnostic tools, such as circuit testers and pressure gauges, to ensure that all systems were installed correctly and functioning well. After system commissioning, the functionality of the pipe jacking machine system was perfected. This fully functional pipe jacking machine system ensures stability and efficiency during construction and is the core equipment in pipe jacking construction.

[0069] S203, based on a fully functional pipe jacking machine system, performs jacking force calculation and verification; calculates the standard value of total jacking force according to the pipe outer diameter, jacking length, overburden thickness and soil parameters, and the result should be within the range of 8000-10000 kN; verifies the thrust capacity of the pipe jacking machine and the main jacking cylinder to ensure that the jacking requirements are met and obtains jacking force parameters that meet the construction requirements;

[0070] The jacking force was calculated and verified. Based on the pipe outer diameter, jacking length, overburden thickness, and soil parameters, the construction team calculated the standard value of the total jacking force, which should be within the range of 8000-10000 kN. The accuracy and reliability of the calculation results were ensured by using a combination of calculation software and manual calculation. After verifying the thrust capacity of the pipe jacking machine and the main jacking cylinder, it was confirmed that these devices met the jacking requirements. Obtaining jacking force parameters that meet the construction requirements is crucial to ensuring construction safety and efficiency; the accurate calculation and verification of these parameters provided solid data support for the pipe jacking construction.

[0071] S204, use the jacking force parameters that meet the construction requirements to verify the bearing capacity of the back structure of the working pit; calculate the maximum jacking force that the back wall can withstand based on the back wall size, earth pressure, passive earth pressure and safety factor, which should be in the range of 15000-18000 kN; verify that the back structure meets the stability and strength requirements, and carry out reinforcement design if necessary to obtain a back structure scheme that meets the bearing requirements;

[0072] SAP2000, STAAD.Pro, or ANSYS software is used to verify the bearing capacity of the backing structure of the working pit. The dimensions of the backing wall, the estimated earth pressure, passive earth pressure, and safety factor are input. The software will calculate the maximum jacking force that the backing wall can withstand, ensuring this force value is between 15,000 and 18,000 kN. Based on the calculation results and relevant national or industry standards, such as the "Code for Design of Building Foundations," the technical team evaluates the stability and strength of the structure. If the analysis shows that the bearing capacity or safety factor of the backing wall does not meet the required standards, a reinforcement plan will be developed, the new bearing capacity after reinforcement will be calculated, and the reinforcement measures will be described in detail. This step ensures the safety and functionality of the backing structure, providing a robust support environment for the smooth progress of the pipe jacking operation.

[0073] S205, under the guidance of the back structure scheme that meets the load-bearing requirements, carried out the reinforcement of the tunnel entrance and the stratum reinforcement treatment; removed the anchor sprayed concrete and grid support at the tunnel entrance, and installed reinforced steel grid and vertical steel bars to form a reinforced ring beam for the tunnel entrance; carried out deep hole grouting reinforcement on the soil within 5-10 meters in front of the tunnel entrance, and increased the unconfined compressive strength to 1.0-1.5 MPa, so as to obtain a stable tunnel entrance and reinforced stratum in front.

[0074] Guided by a back-structure design that met load-bearing requirements, the construction team reinforced the shaft entrance and the surrounding soil. Initially, the anchored shotcrete and grid support at the shaft entrance were removed, and then reinforced steel grids and vertical steel bars were installed to form a reinforced ring beam at the entrance. Subsequently, deep-hole grouting was used to reinforce the soil within 5-10 meters in front of the entrance, increasing the unconfined compressive strength of the soil to 1.0-1.5 MPa. These measures ensured the structural stability of the shaft entrance and the load-bearing capacity of the soil, providing a solid foundation for the smooth entry and operation of the pipe jacking machine and avoiding construction risks caused by soil loosening or collapse.

[0075] In this embodiment, S3 includes:

[0076] S301, carry out the chiseling and cleaning of the opening wall; use a pneumatic hammer and cutting machine to chisel away the wall at the opening, thoroughly remove the steel bars and concrete residue, and ensure that the opening size meets the requirements for the pipe jacking machine head to enter; after cleaning, the opening wall is cleaned.

[0077] The wall around the opening was then cleared and removed. Construction workers used pneumatic drills and cutting machines to precisely remove the wall at the opening, thoroughly clearing away any remaining reinforcing steel and concrete to ensure the opening dimensions met the requirements for the pipe jacking machine. This process resulted in a clean and precisely sized opening wall. This step not only ensured the smooth entry of the pipe jacking machine but also prevented potential structural obstacles during the process, thus improving construction safety and efficiency.

[0078] S302: The cleaned tunnel wall is used for the entry and advancement of the pipe jacking machine head; the pipe jacking machine is started, and the advancing speed is controlled within the range of 5-10 mm per minute. The machine head smoothly enters the tunnel, and the position of the water-stop ring is adjusted to completely seal the groundwater; by monitoring the tilt angle and rotation angle of the machine head, timely correction and adjustment are made to obtain a successfully entered pipe jacking machine head.

[0079] After starting the pipe jacking machine, the cleaned tunnel walls were used for the machine head's entry into the tunnel. The advancing speed was controlled within the range of 5-10 mm per minute to ensure the machine head smoothly entered the tunnel. Simultaneously, the position of the water-stop ring was adjusted to completely seal off groundwater and prevent water from flowing into the construction area. Furthermore, the tilt and rotation angles of the machine head were monitored, and timely adjustments were made to correct any deviations. This process not only ensured the successful entry of the pipe jacking machine head into the tunnel but also guaranteed the accuracy and safety of the entire pipe jacking operation, avoiding structural damage or ground movement during construction.

[0080] S303 controls the initial jacking direction of the jacking head after it has successfully entered the tunnel; the first section of concrete pipe is rigidly connected to the jacking head with multiple bolts to ensure the firmness of the connection; the tilt angle and offset of the jacking head are adjusted by using the correction cylinder and the weight of the jacking head to maintain the stability of the jacking direction and obtain a jacking head with directional correction.

[0081] The construction team controlled the initial jacking direction of the pipe jacking machine head after it successfully entered the tunnel. This operation first involved rigidly connecting the first section of concrete pipe to the jacking machine head using multiple bolts to ensure the stability of the connection. Subsequently, by operating the correction cylinder and utilizing the weight of the jacking machine head itself, the tilt angle and offset of the machine head were precisely adjusted to ensure the stability of the jacking direction. The core of this step is to ensure that the direction of the pipe jacking machine head is strictly aligned with the design axis through fine adjustments, thereby guaranteeing the accuracy and efficiency of the pipe jacking operation. The results of this operation not only ensure the accuracy of the pipe jacking construction but also generate direction correction records, which are important bases for subsequent construction review and quality control.

[0082] S304, under the guidance of the jacking head with directional correction, begins the pipe jacking and correction operation. Measurements are taken every 250-300 mm of advance, and the deviation is controlled within ±20 mm. The axis and elevation of the jacking machine are monitored in real time using a laser guide. The attitude of the jacking machine is adjusted by controlling the correction cylinder to obtain a stable jacking process.

[0083] Guided by the jacking head with directional correction, the pipe jacking and alignment operations commenced. The construction team utilized a laser guide to monitor the jacking machine's axis and elevation in real time. Through the control of the alignment cylinders, they adjusted the jacking machine's attitude to ensure it jacked along the correct axis and elevation. Precise control of the jacking machine's attitude was crucial, as even the slightest deviation could lead to errors in the jacking path, impacting the success of the entire project. Through these meticulous adjustments, the team achieved a stable jacking process, effectively avoiding potential axis misalignment and elevation errors, ensuring efficient and safe construction.

[0084] S305 measures and controls earth pressure and slurry parameters during the stable pipe jacking process; calculates the earth pressure control value at the excavation face based on groundwater pressure and earth pressure, and keeps the slurry chamber pressure within the calculated range; adjusts the slurry specific gravity and flow rate to ensure the stability of the excavation face, reduce surface settlement, and obtain controlled earth pressure and slurry parameters at the excavation face.

[0085] During the pipe jacking process, the construction team measured and controlled earth pressure and slurry parameters to ensure the stability of the excavation face. By measuring groundwater pressure and earth pressure, the team calculated the earth pressure control value for the excavation face, which was typically set within the engineering safety standard range, generally maintaining the slurry chamber pressure at no more than 0.3-0.5 MPa. Furthermore, by adjusting the specific gravity and flow rate of the slurry, the team not only ensured the stability of the excavation face but also effectively reduced surface settlement, which is particularly important in pipe jacking construction in urban areas or other sensitive locations.

[0086] In this embodiment, S4 includes:

[0087] S401, the controlled excavation face earth pressure and slurry parameters are used for the construction of the pipe jacking test section; the entire pipe jacking section is used as the test section, and soil settlement monitoring points are buried at a depth of 1.0-2.0 meters above the top of the pipe; the relationship between jacking speed, slurry parameters and surface settlement is verified through the test section, and the construction parameters are optimized to obtain the optimized jacking construction parameters;

[0088] Controlled earth pressure and slurry parameters at the excavation face were used in the construction of the test section of the pipe jacking project. During this process, the entire pipe jacking section was used as the test section, and soil settlement monitoring points were installed at a depth of 1.0-2.0 meters above the top of the pipe. These monitoring points were used to verify the relationship between jacking speed, slurry parameters, and surface settlement, thereby optimizing construction parameters. This step not only provided valuable experimental data to optimize jacking construction parameters but also helped the construction team adjust and improve construction techniques to adapt to complex geological conditions. The optimized jacking construction parameters obtained will serve as a reference for future construction activities, improving construction efficiency and safety. These activities ultimately resulted in a detailed set of construction records and data reports, providing a scientific basis for project quality management and subsequent work.

[0089] S402, under the guidance of optimized jacking construction parameters, carried out normal tunneling; the jacking speed was controlled within the range of 10-20 mm per minute, the mud specific gravity was between 1.10-1.25, and the flow rates of mud delivery and mud discharge were kept balanced; the pipeline axis and elevation were measured regularly, and the deviation was controlled within ±10 mm to obtain a continuous and stable tunneling process;

[0090] S403 implements drag reduction measures for continuous and stable tunneling processes; uniformly coats the outer wall of each pipe section with an industrial paraffin wax layer of 1-2 mm thickness to improve the sliding properties of the pipe wall; simultaneously performs thixotropic mud injection, with the mud viscosity controlled within the range of 20-25 seconds and the injection pressure between 0.1-0.2 MPa, to obtain a jacking environment with reduced frictional resistance.

[0091] S404 utilizes a jacking environment with reduced frictional resistance for secondary waterproofing of pipelines; a 2-5 mm thick non-woven fabric is wrapped around the outside of the rubber ring at the pipeline interface, and hemp filler is added; after jacking, hemp is applied to the pipeline joint to obtain a pipeline interface with enhanced sealing performance.

[0092] S405, for pipe interfaces with enhanced sealing performance, prepare for the exit operation of the pipe jacking machine head; according to the progress of pipe jacking, reinforce the soil in front of the receiving well opening with double-liquid grouting in advance for a length of 5-10 meters, with the grouting pressure controlled between 0.2-0.5 MPa, to improve the soil strength and obtain the reinforced soil in front of the opening.

[0093] S406, under the condition of the reinforced soil in front of the tunnel entrance, the pipe jacking head is pushed out of the tunnel; the jacking speed is controlled, with the speed range between 5 and 10 millimeters per minute, to ensure that the head enters the receiving well smoothly; before exiting the tunnel, the receiving well wall is removed using a breaker hammer and cutting equipment to locate the pipe outlet position, and the successfully exited pipe jacking head is obtained.

[0094] In this embodiment, it also includes: S5, dismantling and hoisting the pipe jacking head that has successfully exited the tunnel; using a hoisting device with a lifting capacity of 300-350 tons, the pipe jacking head is hoisted from the receiving shaft to the ground to obtain the safely dismantled pipe jacking head.

[0095] In this embodiment, it also includes: S6, after the pipe jacking machine head is safely removed, the pipe is replaced with mud; cement and fly ash are mixed in proportion to prepare grout, and grout is injected through the grouting hole inside the pipe. The number of grouting is not less than three times, the interval is not more than 24 hours, and the grouting pressure is controlled between 0.2-0.5 MPa, so as to obtain a pipe with mud replacement completed.

[0096] In this embodiment, it also includes: S7, conducting a water tightness test on the pipeline after the mud replacement is completed; observing the amount of water seepage within the pipeline over 24 hours by recording the amount of water seepage inside the pipeline to determine the sealing performance of the pipeline; and treating local seepage points with chemical grouting to ensure that the amount of water seepage is within the allowable range of the specification, thereby obtaining a pipeline project that meets the sealing requirements.

[0097] Here, according to the standard "Code for Construction and Acceptance of Water Supply and Drainage Pipeline Engineering" (GB50268-2008), the methods for water tightness testing and the allowable leakage volume are specified in detail. According to this standard, during the water tightness test, the leakage volume is usually observed over 24 hours. If the leakage volume exceeds the specified value, the sealing performance is considered unqualified. The specified value is adjusted according to the pipe diameter and the length of the test section. Generally, the leakage volume should not exceed 0.07 cubic meters per kilometer of pipe per day. If localized leaks are found during the water tightness test, methods such as chemical grouting can be used for treatment. This method involves injecting specific chemical substances into the leak point, which quickly solidifies and seals the leak, thereby reducing leakage and meeting the requirements of the standard. Through such testing and treatment measures, the sealing qualification of the pipeline can be effectively judged and guaranteed, ensuring project quality and operational safety.

[0098] In this embodiment, in step S102, the side length of the conductor is controlled within the range of 50-100 meters.

[0099] Secondly, the present invention also provides a technical solution, a pipe jacking construction method, comprising the following steps:

[0100] Accurately establish the terrain and control network, re-measure the traverse network and leveling network, and ensure an accuracy of ±1mm. Establish the plane and elevation control network. Then, lay out the center line of the shaft and the pipe jacking pipeline. At the same time, set up control points at the bottom of the shaft and install the guide rail system. The installation of the pipe jacking machine must ensure that its axis is aligned with the axis of the guide rail and the main jacking cylinder.

[0101] The installation and commissioning of the pipe jacking machine, including the electrical circuit, oil circuit and mud system, are carried out to ensure that the machine functions properly. The thrust is checked by the standard value of the jacking force to ensure that it meets the jacking requirements. After the pipe jacking machine successfully enters the tunnel, its jacking direction is controlled and corrected to maintain the stability of the jacking direction.

[0102] The soil pressure and slurry parameters at the excavation face are controlled, construction parameters are optimized, and deviations are corrected by regularly monitoring the pipeline axis and elevation. Before the pipe jacking machine head exits the tunnel, the soil in front of the receiving well is reinforced. After the machine head successfully enters the receiving well, the entire pipe jacking construction process is completed.

[0103] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A pipe jacking construction process, characterized in that, Includes the following steps: S1. Establishment of topography and control network: Re-survey the traverse network, leveling network and control points provided by the construction unit to ensure an accuracy of ±1mm. The surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points. After completion, certified control point data is generated, and a plane control network and an elevation control network are established. In addition, a third-order traverse plane control network is set up around the jacking shaft. The fourth-order leveling method is used to form a closed traverse network with the closure error controlled within 12mm. S2: Installation of the guide rail system and adjustment of the pipe jacking machine equipment. Based on certified control point data, the center of the shaft and the center line of the pipe jacking are laid out to ensure that the laying out error is within ±3mm. Control points are set up at the bottom of the shaft and the control information is transmitted to the bottom of the shaft to ensure that the elevation transmission accuracy is within ±3mm. When installing the guide rail system, ensure that the guide rail is straight, parallel and at the same height, and the axis position deviation is controlled within 3mm. The top surface elevation and track gauge deviation are both within the strict control range. After installation, the guide rail system with the required accuracy is used for the installation of the pipe jacking machine to ensure that the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder, and that the position of the pipe jacking machine is accurate. S3, Pipe jacking operation and monitoring: Install and debug the circuit, oil circuit and mud system of the pipe jacking machine that has been put in place; check the standard value of total jacking force and the thrust of the pipe jacking machine and the main jacking cylinder; chisel and clean the wall of the tunnel opening to ensure that the size of the tunnel opening can accommodate the pipe jacking machine head; after the pipe jacking machine head successfully enters the tunnel, control the jacking direction and maintain the stability of the direction through correction adjustment. S4. Optimize construction parameters and strengthen the structure. Measure and control earth pressure and slurry parameters. Calculate the earth pressure control value at the excavation face based on groundwater pressure and earth pressure. Adjust the slurry specific gravity and flow rate to ensure the stability of the excavation face and reduce surface settlement. The construction of the pipe jacking test section verifies the relationship between jacking speed, slurry parameters, and surface settlement, thereby optimizing construction parameters and carrying out normal tunneling. Control the jacking speed and slurry specific gravity. Regularly measure the pipeline axis and elevation to correct errors. Finally, prepare for the exit operation of the pipe jacking head. Reinforce the soil in front of the receiving shaft opening in advance to ensure the head smoothly enters the receiving shaft and obtains a successfully exiting pipe jacking head. S1 includes: S101, Conduct topographic surveying and control point verification of the construction area, use instruments to re-measure the traverse network and leveling network and their control points provided by the construction unit, with an accuracy within ±1mm; the surveying work includes verifying the position, elevation and coordinates of existing traverse points and leveling points, and densifying the control points as needed; after the survey is completed, the verified control point data is obtained; S102, establish a plane control network and an elevation control network based on the verified control point data; set up a third-order traverse plane control network near the jacking shaft to form a closed traverse network; use fourth-order leveling method for elevation control, use a precision level, and control the closure error within 12mm; thus obtaining a construction control network that meets the accuracy requirements. S103, based on the construction control network that meets the accuracy requirements, lay out the center of the shaft and the center line of the jacking pipe; using a total station and a level, accurately transfer the design coordinates and elevations of the shaft and pipe to the construction site, with the layout error controlled within ±3mm; after layout, set up markers and take protective measures to obtain the axis and elevation control markers of the construction site; S104, the axis and elevation control marks of the construction site are transferred to the bottom of the shaft; the elevation and coordinates are transferred from the ground to the bottom of the shaft using the suspended steel tape method, and two level instruments are used for synchronous observation to ensure that the elevation transfer accuracy is within ±3mm; the control points at the bottom of the shaft are set up to obtain the construction control points at the bottom of the shaft; S105, at the construction control point at the bottom of the shaft, install a guide rail system. During installation, ensure that the two guide rails are straight, parallel, and at the same height, and that the longitudinal slope is consistent with the design slope of the pipeline. The guide rails are made of I63a I-beams, 24a and 22a channel steel, and are 5-10 meters long. The axial position deviation of the guide rails shall not exceed 3mm, the top surface elevation deviation shall be controlled within ±3mm, and the track gauge deviation shall be controlled within ±2mm. After installation, a guide rail system with the required accuracy is obtained.

2. The pipe jacking construction process according to claim 1, characterized in that, S2 includes: S201, Use the guide rail system with the required accuracy for the installation of the pipe jacking machine; Use a hoisting device with a lifting capacity of 300-350 tons to place the slurry balance pipe jacking machine weighing 60-70 tons on the guide rail, with the front end of the pipe jacking machine 0.3-0.5 meters away from the shaft wall; After installation, check whether the axis of the pipe jacking machine is consistent with the axis of the guide rail and the main jacking cylinder to obtain the accurately positioned pipe jacking machine equipment; S202, Install and debug the electrical circuit, oil circuit and mud system of the accurately positioned pipe jacking machine; connect the main jacking cylinder, oil pump power station, mud inlet and outlet pipes and thixotropic mud system, and install monitoring instruments; after debugging, a fully functional pipe jacking machine system is obtained. S203. Based on the fully functional pipe jacking machine system, perform jacking force calculation and verification; calculate the standard value of total jacking force according to the pipe outer diameter, jacking length, overburden thickness and soil parameters, and the result should be within the range of 8000-10000 kN; verify the thrust capacity of the pipe jacking machine and the main jacking cylinder to ensure that the jacking requirements are met and obtain jacking force parameters that meet the construction requirements; S204, use the jacking force parameters that meet the construction requirements to verify the bearing capacity of the back structure of the working pit; calculate the maximum jacking force that the back wall can withstand based on the back wall size, earth pressure, passive earth pressure and safety factor, which should be in the range of 15000-18000 kN; verify that the back structure meets the stability and strength requirements, and carry out reinforcement design if necessary to obtain a back structure scheme that meets the bearing requirements; S205, under the guidance of the back structure scheme that meets the load-bearing requirements, the opening and the stratum are reinforced; the anchor sprayed concrete and grid support at the opening of the vertical shaft are removed, and a reinforced steel grid and vertical steel bars are installed to form a reinforced ring beam for the opening; the soil within 5-10 meters in front of the opening is reinforced by deep hole grouting, and the unconfined compressive strength is increased to 1.0-1.5 MPa, so as to obtain a stable opening and a reinforced stratum in front.

3. The pipe jacking construction process according to claim 2, characterized in that, S3 includes: S301, carry out the chiseling and cleaning of the opening wall; use a pneumatic hammer and cutting machine to chisel away the wall at the opening, thoroughly remove the steel bars and concrete residue, and ensure that the opening size meets the requirements for the pipe jacking machine head to enter; after cleaning, the opening wall is cleaned. S302, the cleaned tunnel wall is used for the entry and advancement of the pipe jacking machine head; the pipe jacking machine is started, and the advancing speed is controlled within the range of 5-10 mm per minute. The machine head smoothly enters the tunnel, and the position of the water-stop ring is adjusted to completely seal the groundwater; by monitoring the tilt angle and rotation angle of the machine head, timely correction and adjustment are made to obtain a successfully entered pipe jacking machine head. S303, control the initial jacking direction of the jacking head that has successfully entered the tunnel; rigidly connect the first section of concrete pipe to the jacking head with multiple bolts to ensure the firmness of the connection; use the correction cylinder and the weight of the jacking head to adjust the tilt angle and offset of the jacking head to maintain the stability of the jacking direction and obtain a jacking head with corrected direction. S304, under the guidance of the jacking head with the corrected direction, the pipe jacking and correction operation begins. A measurement is taken every 250-300 mm of advance, and the deviation is controlled within ±20 mm. The axis and elevation of the jacking machine are monitored in real time using a laser guide. The attitude of the jacking machine is adjusted by controlling the correction cylinder to obtain a stable jacking process. S305, the soil pressure and slurry parameters are measured and controlled during the stable pipe jacking process; the soil pressure control value at the excavation face is calculated based on the groundwater pressure and soil pressure, and the pressure in the slurry chamber is kept within the calculation range; the slurry specific gravity and flow rate are adjusted to ensure the stability of the excavation face, reduce surface settlement, and obtain controlled soil pressure and slurry parameters at the excavation face.

4. The pipe jacking construction process according to claim 3, characterized in that, S4 includes: S401, the controlled excavation face earth pressure and slurry parameters are used for the construction of the pipe jacking test section; the entire pipe jacking section is used as the test section, and soil settlement monitoring points are buried at a depth of 1.0-2.0 meters above the top of the pipe; the relationship between jacking speed, slurry parameters and surface settlement is verified through the test section, and the construction parameters are optimized to obtain the optimized jacking construction parameters; S402, under the guidance of the optimized jacking construction parameters, normal tunneling is carried out; the jacking speed is controlled within the range of 10-20 mm per minute, the mud specific gravity is between 1.10-1.25, and the flow rates of mud delivery water and mud discharge water are kept in balance; the pipeline axis and elevation are measured regularly, and the deviation is controlled within ±10 mm to obtain a continuous and stable tunneling process; S403, implement drag reduction measures for the continuous and stable tunneling process; uniformly apply industrial paraffin wax with a thickness of 1-2 mm to the outer wall of each pipe section to improve the sliding properties of the pipe wall; simultaneously carry out thixotropic mud injection operation, with the mud viscosity controlled within the range of 20-25 seconds and the injection pressure between 0.1-0.2 MPa, to obtain a jacking environment with reduced frictional resistance; S404, the jacking environment with reduced frictional resistance is used for secondary waterproofing of the pipeline; a non-woven fabric with a thickness of 2-5 mm is wrapped around the outside of the rubber ring of the pipeline interface, and an oil-hemp filler is added; after jacking, the pipeline joint is treated with oil-hemp to obtain a pipeline interface with enhanced sealing performance. S405, after obtaining the pipe interface with enhanced sealing performance, prepare for the exit operation of the pipe jacking machine head; according to the progress of pipe jacking, perform double-liquid grouting reinforcement on the soil in front of the receiving well opening for a length of 5-10 meters in advance, with the grouting pressure controlled between 0.2-0.5 MPa to improve the soil strength and obtain the reinforced soil in front of the opening. S406 After obtaining the reinforced soil in front of the tunnel opening, the pipe jacking head is pushed out of the tunnel; the jacking speed is controlled to ensure that the head enters the receiving well smoothly; before exiting the tunnel, the receiving well wall is removed using a breaker and cutting equipment to locate the pipe outlet position, and the pipe jacking head that has successfully exited the tunnel is obtained.

5. The pipe jacking construction process according to claim 4, characterized in that, Also includes: S5, dismantle and hoist the pipe jacking head that has successfully exited the tunnel; Using hoisting equipment with a lifting capacity of 300-350 tons, the pipe jacking head is lifted from the receiving shaft to the ground, and the pipe jacking head is safely dismantled.

6. The pipe jacking construction process according to claim 5, characterized in that, Also includes: S6. After obtaining the safely dismantled pipe jacking head, the pipeline is slurry replaced; cement and fly ash are mixed in proportion to prepare slurry, and grout is injected through the grouting holes inside the pipeline. The grouting is performed no less than three times, with an interval of no more than 24 hours. The grouting pressure is controlled between 0.2 and 0.5 MPa to obtain a pipeline with slurry replacement completed.

7. The pipe jacking construction process according to claim 6, characterized in that, Also includes: S7. Conduct a water tightness test on the pipeline after the mud replacement is completed; record the amount of water seepage in the pipeline and observe the amount of water seepage within 24 hours to determine the sealing performance of the pipeline; for local seepage points, use chemical grouting to treat them so that the amount of water seepage is within the allowable range of the specification, and obtain a pipeline project that meets the sealing requirements.

8. The pipe jacking construction process according to claim 1, characterized in that: In step S102, the side length of the conductor is controlled within the range of 50-100 meters.

9. The construction method of pipe jacking construction technology according to any one of claims 1 to 8, characterized in that, Includes the following steps: Accurately establish the terrain and control network, re-measure the traverse network and leveling network, and ensure an accuracy of ±1mm. Establish the plane and elevation control network. Then, lay out the center line of the shaft and the pipe jacking pipeline. At the same time, set up control points at the bottom of the shaft and install the guide rail system. The installation of the pipe jacking machine must ensure that its axis is aligned with the axis of the guide rail and the main jacking cylinder. The installation and commissioning of the pipe jacking machine, including the electrical circuit, oil circuit and mud system, are carried out to ensure that the machine functions properly. The thrust is checked by the standard value of the jacking force to ensure that it meets the jacking requirements. After the pipe jacking machine successfully enters the tunnel, its jacking direction is controlled and corrected to maintain the stability of the jacking direction. The soil pressure and slurry parameters at the excavation face are controlled, construction parameters are optimized, and deviations are corrected by regularly monitoring the pipeline axis and elevation. Before the pipe jacking machine head exits the tunnel, the soil in front of the receiving well is reinforced. After the machine head successfully enters the receiving well, the entire pipe jacking construction process is completed.

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