Pipe-jacking tunnel construction method

Abstract

The invention relates to a pipe-jacking tunnel construction method. The method comprises the following steps that open caisson construction is conducted; constructing a cement mixing pile; pipe jacking construction is conducted, specifically, a main jacking device and a pipe jacking machine are installed in the working well, a deviation rectifying intermediate jacking station is installed at the tail end of the pipe jacking machine, tunnel sleeves are continuously installed along with jacking of the pipe jacking machine, and jacking intermediate jacking stations are installed among the multiple continuous tunnel sleeves; in the jacking process, the jacking direction of the pipe jacking machine is monitored through a monitoring system, and the jacking direction of the pipe jacking machine is rectified in real time in combination with a rectifying system of the pipe jacking machine and a rectifying intermediate jacking station; performing grouting construction; and hole ejection construction is conducted till the pipe jacking machine completely goes out of the hole, and construction is completed. According to the pipe-jacking tunnel construction method, real-time deviation correction can be conducted in the tunneling process according to the characteristics of the extra-small hydraulic tunnel, and the construction quality of the extra-small hydraulic tunnel is guaranteed on the premise that the safety risk of operators is reduced and the construction period is shortened.

Description

Technical Field

[0001] This application relates to the technical field of civil engineering construction, and more specifically, to a pipe jacking tunnel construction method. Background Art

[0002] Common construction methods for hydraulic tunnels include the excavation method. When encountering unstable tunnel geology, large soil moisture content, and the presence of karst caves, during construction, personnel directly come into contact with the front heading face. When risks such as heading face collapse, mud and water inrush occur, it will endanger the on-site personnel.

[0003] During the initial support shotcrete construction, according to the shotcrete specification requirements and the on-site rebound phenomenon, when shotcreting in the operation space of a very small hydraulic tunnel, it is impossible to be perpendicular to the rock surface, which cannot guarantee the shotcrete quality, increases the possibility of initial support deformation and collapse of the surrounding rock, and at the same time, a large amount of rebound results in poor air quality and poor visibility, making it impossible to observe the heading face situation. When emergencies occur, they cannot be detected in time, bringing great safety risks to construction personnel and also unable to ensure the health of construction personnel.

[0004] At the same time, during the construction of tunnels with a smaller diameter, especially in very small hydraulic tunnels with too small a clearance, only specially modified small vehicles can be used for muck transportation, and it is impossible to turn around inside the tunnel. It can only reverse into the tunnel from the entrance. When driving in reverse for a long distance, there are high traffic risks when reversing in the tunnel. There is a risk of mechanical injury when the loading machine and the transport vehicle operate in a narrow space, and the mucking time is slow and the efficiency is low.

[0005] At the same time, the excavation volume of the excavation method construction is large and the construction period is long. When encountering the urgent water passing requirement of a very small hydraulic tunnel, it is difficult to obtain water passing as soon as possible. Summary of the Invention

[0006] The purpose of this application is to provide a pipe jacking tunnel construction method, which can shorten the construction period of a very small hydraulic tunnel and at the same time reduce the safety risks of operators.

[0007] To achieve the above purpose, the present invention provides a pipe jacking tunnel construction method, including the following steps:

[0008] Caisson construction, excavating the working shaft and the receiving shaft for the tunnel pipe jacking;

[0009] Cement mixing pile construction, constructing mixing piles around the openings of the working shaft and the starting shaft;

[0010] Pipe jacking construction, installing the main jacking device and the pipe jacking machine in the working shaft, installing the deviation correction relay room at the tail end of the pipe jacking machine, continuously installing tunnel sleeves along with the jacking of the pipe jacking machine, and installing the jacking relay room between multiple consecutive tunnel sleeves;

[0011] During the jacking process, the jacking direction of the pipe jacking machine is monitored by a monitoring system, and the jacking direction of the pipe jacking machine is corrected in real time by combining the self-aligning system of the pipe jacking machine and the alignment relay chamber.

[0012] Grouting construction. During the pipe jacking construction, the synchronous grouting method of grouting while tunneling is adopted to fill the gap between the tunnel casing and the surrounding strata when the pipe jacking machine advances forward.

[0013] Jacking out of the hole construction. Before the head of the pipe jacking machine reaches the opening of the receiving well, stop jacking. Install a receiving base in the receiving well and break through the opening of the receiving well until the pipe jacking machine completely exits the hole to complete the construction.

[0014] In an alternative embodiment, both the working well and the receiving well are rectangular caissons. The construction of the caisson wall is made in sections. First, the cutting edge part is constructed, and then the upper well wall part is constructed. The secondary production and sectional sinking method is adopted, and the caisson is sunk by using an excavator to take soil and manual soil excavation.

[0015] After the caisson construction, two rows of mixing piles are constructed around the openings of the caisson for entry and exit. The pile diameter is 60 cm, the overlap is 20 cm, the spacing is 50 cm, and the pile length is 12 m.

[0016] In an alternative embodiment, the main jacking device includes a backrest, a main jacking guide rail, a main jacking oil cylinder, and a main jacking pump station. The pipe jacking machine includes a head shell. After hoisting and installing the pipe jacking machine in the working well and jacking it into the hole, an alignment relay chamber is installed at the tail end of the head shell, and then a tunnel casing is installed at the tail end of the alignment relay chamber. During the jacking process, according to the change of the thrust of the main jacking oil cylinder, a jacking relay chamber is installed between the casing segments formed by different continuous tunnel casings.

[0017] In an alternative embodiment, the alignment relay chamber includes a plurality of relay chamber alignment oil cylinders evenly distributed at circumferential intervals, the pipe jacking machine includes a plurality of pipe jacking machine alignment oil cylinders evenly distributed at circumferential intervals, the number of the relay chamber alignment oil cylinders is greater than the number of the pipe jacking machine alignment oil cylinders, and the two different alignment oil cylinders are arranged staggeredly in the circumferential direction.

[0018] In an alternative embodiment, the monitoring system includes a light target unit, a display and monitoring unit, and a laser emission unit;

[0019] The light target unit includes a light target sensor arranged at the front end of the head shell. The light target sensor is used to receive the laser beam emitted by the laser emission unit to form a laser guiding point. The laser emission unit is installed on the tunnel casing for jacking into the hole;

[0020] The display and monitoring unit is used to receive the jacking data with the laser guiding point as a reference, and transmit the jacking data to the electronic control unit for the operator to refer to and correct the pipe jacking construction system through the electronic control unit.

[0021] In an alternative embodiment, when it is detected and determined by the display monitoring unit that the jacking direction is away from the design axis of the tunnel, it is judged whether the included angle between the jacking direction and the design axis of the tunnel is less than the deviation threshold. If it is less than the deviation threshold, the jacking direction of the pipe jacking machine is directly corrected by the deviation correction cylinder of the pipe jacking machine. After the corrected jacking direction is away from the design axis of the tunnel, the driving oil pressure of the deviation correction cylinder of the pipe jacking machine is removed. Under the double extrusion of the main jacking thrust and the front-end formation earth pressure, the offset jacking direction of the pipe jacking machine coincides with the design axis, and the deviation correction cylinder of the pipe jacking machine is pressed to reset, ending the deviation correction;

[0022] If it is detected and judged that the included angle between the jacking direction and the design axis of the tunnel is greater than the deviation threshold, first, the jacking direction of the pipe jacking machine is corrected by the deviation correction cylinder of the pipe jacking machine. After the corrected jacking direction is away from the design axis of the tunnel, the deviation correction cylinder of the relay jack corresponding to the position of the deviation correction cylinder of the pipe jacking machine is started to suppress the offset jacking direction after the pipe jacking machine is corrected. At the same time, the driving oil pressures of the deviation correction cylinder of the relay jack and the deviation correction cylinder of the pipe jacking machine are removed. Under the double extrusion of the main jacking thrust and the front-end formation earth pressure, the offset jacking direction of the pipe jacking machine is reset to coincide with the design axis, and the deviation correction cylinder of the relay jack and the deviation correction cylinder of the pipe jacking machine are pressed to reset, ending the deviation correction.

[0023] In an alternative embodiment, the deviation threshold corresponding to the included angle between the jacking direction of the pipe jacking machine and the design axis of the tunnel is the included angle at which, under the state that the deviation correction cylinder of the pipe jacking machine outputs the maximum jacking distance, after removing the oil pressure of the deviation correction cylinder of the pipe jacking machine, the jacking direction of the pipe jacking machine can coincide with the design axis and the deviation correction cylinder of the pipe jacking machine is pressed to reset under the double extrusion of the main jacking thrust and the front-end formation earth pressure.

[0024] In an alternative embodiment, the jacking data during the jacking process is collected in real time through the monitoring system, including the main jacking thrust and the front-end formation earth pressure in the state where the jacking direction of the pipe jacking machine coincides with the design axis of the tunnel. And the electronic control unit calculates and determines, according to the collected main jacking thrust and front-end formation earth pressure, and the oil pressure of the deviation correction cylinder of the pipe jacking machine obtained according to the equipment model, the offset angle of the pipe jacking machine relative to the design axis at which, under the state that the deviation correction cylinder of the pipe jacking machine outputs the maximum jacking distance, the jacking direction of the pipe jacking machine can coincide with the design axis and the deviation correction cylinder of the pipe jacking machine is pressed to reset under the double extrusion, and takes this offset angle as the deviation threshold.

[0025] In an alternative embodiment, every 50 m during the jacking process, the laser emitting unit is reinstalled and fixed. The laser emitting unit includes a total station and a level. The total station is used to emit laser, and the level is used to measure the coordinates of the total station and the elevation of the pipe jacking tunnel;

[0026] The total station and the level are both electrically connected to the electric control unit, and are used to transmit the coordinates of the total station, the direction accuracy of the laser beam, and the distance to the electric control unit.

[0027] In an alternative embodiment, during the jacking process, thixotropic slurry is continuously injected through the grouting holes provided at the tail of the pipe jacking machine and on each section of the tunnel casing. After the jacking construction is completed, secondary supplementary grouting is carried out through the grouting holes.

[0028] Through the pipe jacking tunnel construction method in the present application, it is possible to carry out the tunneling of the tunnel in the form of pipe jacking according to the characteristics of the extra-small hydraulic tunnel, and real-time deviation correction can be carried out during the tunneling process. On the premise of reducing the safety risks of the operators and shortening the construction period, the construction quality of the extra-small hydraulic tunnel is guaranteed.

[0029] Other features and advantages of the present application will be described in detail in the subsequent specific embodiment part. Brief Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic diagram of the overall process of the pipe jacking tunnel construction method in the present application;

[0032] Figure 2 It is a schematic diagram of the process during the deviation correction of the pipe jacking machine. Detailed Description of the Embodiments

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Usually, the components of the embodiments of the present application described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0034] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "inner" and "outer" is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the products of this application are customarily placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application. In addition, terms such as "first" and "second" are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0035] In the description of the present application, it should also be noted that unless otherwise clearly specified and defined, the terms "set" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0036] See Figure 1 - Figure 2 , in the pipe jacking tunnel construction method of the present invention, the pipe jacking construction of a particularly small hydraulic tunnel is mainly carried out by a pipe jacking machine. By setting the pipe jacking machine and arranging necessary deviation correction structures around the pipe jacking machine to adjust the attitude of the pipe jacking machine, through the arranged deviation correction structures, primary deviation correction of the pipe jacking machine itself and secondary deviation correction of the whole pipe jacking machine can be respectively constituted. By combining the two, the overall jacking direction of the pipe jacking construction system can be ensured to be on the axis of the particularly small hydraulic tunnel.

[0037] The pipe jacking tunnel construction method in the present application is mainly reflected in the deviation correction angle. The jacking direction of the pipe jacking machine is monitored in real time through a monitoring system, and based on the judgment of the deviation angle between the jacking direction and the design axis of the tunnel, primary deviation correction is carried out specifically, and whether secondary deviation correction is necessary is determined, so as to ensure the stability of the jacking stratum during the jacking process.

[0038] See Figure 1 , the pipe jacking tunnel construction method in the present invention includes the following steps:

[0039] Construction of the caisson, excavating the working shaft and receiving shaft for pipe jacking of the tunnel. Based on the construction characteristics of the particularly small tunnel, both the working shaft and the receiving shaft in the present application are rectangular caissons. The construction of the caisson wall is made in sections. First, the cutting edge part is constructed, and then the upper shaft wall part is constructed. The secondary production and sectional sinking method is adopted, and the primary production height is about 4 - 5m. The caisson is sunk by using an excavator to take soil and manual soil excavation. Since the caisson sinking amount is relatively large and the excavator cannot smoothly dig the soil, a small excavator inside the well is used in cooperation with manual excavation, and the soil is lifted out by a hanging bucket.

[0040] After the caisson construction, the cement mixing piles are constructed. Specifically, two rows of mixing piles are constructed around the inlet and outlet openings of the caisson. The pile diameter is 60 cm, the overlap is 20 cm, the spacing is 50 cm, and the pile length is 12 m. Its function is to reinforce the soil around the caisson opening, prevent soil collapse, ensure the safety of the pipe jacking machine during entry and exit, and can effectively act as a cut-off curtain.

[0041] All the cement mixing piles adopt the two-way cement mixing process. The diameter of the cement mixing piles is 60 cm, which are arranged in a square pattern in the plane with a spacing of 50 cm and an overlap of 20 cm. The mixing pile material uses 42.5 ordinary Portland cement. The designed pile length is 12 m, the designed water-cement ratio is 0.45 - 0.55:1, the designed cement penetration ratio is 12%, the drilling and grouting speed is 0.5 - 0.7 m / min, and the lifting speed is 0.6 - 0.8 m / min.

[0042] Prepare the slurry according to the mix ratio and water-cement ratio, etc. After the cement slurry is fully stirred and evenly mixed, pour it into the aggregate hopper. Start the two-way mixing pile construction machinery, adjust the mixing blades to fully expand to the predetermined diameter (d = 60 cm), and the machinery touches the soil downward along the guide frame. The lower set of impellers rotates to forcibly cut the soil. At the same time, start the slurry pump, and spray the cement slurry into the soil through the nozzles fixed on the blades, so that the solidifying material adheres to the soil where voids are generated by rotation on the spot and rotates to half a circle. The upper set of impellers rotates and stirs to mix the soil and the slurry solidifying material together to ensure uniform grouting.

[0043] During the pipe jacking construction process, first install the main jacking device and the pipe jacking machine in the working shaft. The main jacking device includes the backrest, main jacking guide rail, main jacking cylinder, and main jacking pump station. The pipe jacking machine includes the machine head shell. After hoisting and installing the pipe jacking machine in the working shaft and jacking it into the opening, install the deviation correction relay room at the tail end of the machine head shell. The deviation correction relay room is mainly used to perform secondary deviation correction on the pipe jacking machine body when the self-deviation correction structure of the pipe jacking machine cannot meet the deviation correction requirements.

[0044] Then install the tunnel casing at the tail end of the deviation correction relay room, and install the jacking relay room between the casing segments formed by different continuous tunnel casings according to the change of the thrust of the main jacking cylinder during the jacking process.

[0045] In this application, the number of jacking relay rooms set is determined by the change of the thrust of the main jacking cylinder of the pipe jacking machine during the jacking process. Specifically, as the tunnel casing is continuously installed and increased, when the total thrust of the main jacking cylinder reaches 50% of the total thrust of the jacking relay room, place the first jacking relay room; when the total thrust of the main jacking cylinder reaches 80% of the total thrust of the jacking relay room, place the second jacking relay room; when the total thrust of the main jacking cylinder continues to reach 80% of the total thrust of the jacking relay room, place the third jacking relay room; during the jacking process, when the total thrust of the main jacking cylinder reaches 90%, start the jacking relay room to carry out relay jacking.

[0046] In this application, by setting a deviation rectification relay room between the pipe jacking machine and the first tunnel casing, the jacking direction of the whole pipe jacking machine can be rectified for the second time. The setting of the deviation rectification relay room is mainly to rectify the pipe jacking machine, rather than the rectification operation carried out by the pipe jacking machine itself.

[0047] Through the mutual cooperation between the deviation rectification relay room and the pipe jacking machine, the deviation rectification requirements can be met when the first deviation rectification operation of the pipe jacking machine's own deviation rectification system cannot make the jacking direction return to the tunnel design axis.

[0048] Specifically, the deviation rectification relay room includes a plurality of relay room deviation rectification oil cylinders evenly distributed at circumferential intervals. The deviation rectification system of the pipe jacking machine includes a plurality of pipe jacking machine deviation rectification oil cylinders evenly distributed at circumferential intervals. During normal use, the relay room deviation rectification oil cylinders and the pipe jacking machine deviation rectification oil cylinders do not act. When it is detected by the monitoring system that the jacking direction of the pipe jacking machine deviates from the tunnel design axis, first judge whether the first deviation rectification of the pipe jacking machine itself can meet the deviation rectification requirements. If it can meet, the pipe jacking machine deviation rectification oil cylinders are started. If it cannot meet, the pipe jacking machine deviation rectification oil cylinders first perform the first deviation rectification, and then the relay room deviation rectification oil cylinders act to assist the pipe jacking machine in performing the second deviation rectification until the jacking direction of the pipe jacking machine returns to the jacking state that coincides with the tunnel design axis.

[0049] The number of relay room deviation rectification oil cylinders is greater than the number of pipe jacking machine deviation rectification oil cylinders, and the two different deviation rectification oil cylinders are arranged staggeredly in the circumferential direction. The relay room deviation rectification oil cylinders and the pipe jacking machine deviation rectification oil cylinders are independently set and can be controlled separately.

[0050] When the second deviation rectification of the pipe jacking machine is required, by controlling the relay room deviation rectification oil cylinders that need to act, with the tunnel casing as the backrest foundation, the jacking direction of the pipe jacking machine is adjusted. Combining with the pipe jacking machine deviation rectification oil cylinders on the pipe jacking machine, it can be quickly rectified and returned to the correct position under the synergistic action of double deviation rectification, or the jacking length of rectifying and returning to the correct position can be shortened.

[0051] In one specific setting form, the deviation rectification relay room specifically includes a relay room front shell and a relay room rear shell with a split structure and a relative offset gap between them. At least two sealing rings are arranged between the relay room front shell and the relay room rear shell to prevent the soil body of the jacking stratum from entering the deviation rectification relay room. The relay room front shell abuts against the rear shell of the pipe jacking machine, and the relay room rear shell abuts against the front end of the first tunnel casing.

[0052] The relay room deviation rectification oil cylinders specifically include 8 arranged at circumferential intervals. The 8 relay room deviation rectification oil cylinders are fixedly installed on the relay room rear shell. A rear shell tail end annular plate is arranged at the tail of the relay room rear shell, and the tail ends of the 8 relay room deviation rectification oil cylinders are fixedly abutted against the rear shell tail end annular plate.

[0053] The piston of the deviation rectification oil cylinder in the relay chamber abuts against the tail end of the front shell of the relay chamber. When the deviation rectification oil cylinder in the relay chamber pushes forward, the piston can directly push the annular plate at the tail end of the front shell. Combining with the gap between the front shell and the rear shell of the relay chamber, the axis of the front shell of the relay chamber can be offset relative to the axis of the rear shell of the relay chamber. Combining with the front shell of the relay chamber abutting against the rear shell of the pipe jacking machine, the offset of the front shell of the relay chamber can be transmitted to the rear shell of the pipe jacking machine, realizing the deviation rectification and pushing of the pipe jacking machine body.

[0054] Further, there are four deviation rectification oil cylinders for the pipe jacking machine. The 8 deviation rectification oil cylinders in the relay chamber and the four deviation rectification oil cylinders for the pipe jacking machine are arranged staggeredly in the circumferential direction, which can output deviation rectification driving forces targeted at different angular orientations, thereby ensuring the accuracy in the deviation rectification operation. At the same time, the 8 deviation rectification oil cylinders in the relay chamber can also output more balanced deviation rectification thrusts of the relay chamber, echoing and cooperating with the opposite sides in the circumferential direction of the deviation rectification oil cylinders for the pipe jacking machine to ensure the stability and reliability of the deviation rectification.

[0055] Through the mutual cooperation of the deviation rectification oil cylinders for the pipe jacking machine and the deviation rectification oil cylinders in the relay chamber in the present invention, corresponding deviation rectification complementarity can be formed, thus achieving the technical purpose of quickly rectifying the deviation and timely correcting the jacking axis. At the same time, through the cooperation of the two, a deviation rectification operation of dynamic collaborative reset can be constituted.

[0056] When there is a deviation in the jacking direction of the pipe jacking machine, for example, when there is a countersunk deviation in the lower right direction, if the pipe jacking machine itself cannot correct the jacking direction to be straight, first, the deviation rectification oil cylinder for the pipe jacking machine located in the lower right direction is triggered to eject, correcting the direction of the pipe jacking machine. Then, the two deviation rectification oil cylinders in the upper left direction of the deviation rectification relay chamber are ejected outward, creating conditions for the subsequent process of dynamic collaborative reset.

[0057] The dynamic collaborative reset specifically includes that the deviation rectification oil cylinders in the relay chamber and the deviation rectification oil cylinders for the pipe jacking machine on the opposite sides in the circumferential direction do not retract after ejection, but rely on the mutual cooperation of the main jacking thrust and the soil pressure at the front end of the jacking during the jacking process in the deviation rectification state to realize the automatic reset of the pipe jacking machine, and realize that the deviation rectification oil cylinders in the relay chamber and the deviation rectification oil cylinders for the pipe jacking machine are extruded by the soil pressure at the front end of the jacking, and the oil cylinders themselves retract and reset along with the reset of the jacking direction of the pipe jacking machine. The overall purpose is to keep the pipe jacking machine in contact with and pressing against the formation at all times to prevent the formation from becoming unstable.

[0058] Specifically, after the deviation rectification oil cylinder in the lower right direction ejects and resets the pipe jacking machine to the tunnel axis direction, it cannot immediately retract, because the retraction action will directly cause the deviation of the pipe jacking machine, and at the same time, a gap will be generated between the pipe jacking machine and the jacking soil layer, which will cause the instability of the tunneling formation soil pressure, constituting the risk of secondary deviation or formation collapse.

[0059] To avoid the above risks, after the deviation rectification cylinder of the pipe jacking machine in the lower right direction extends, and after advancing a certain distance in the upper left deviation rectification direction output by the pipe jacking machine, along with the trend of the deviation rectification advancing direction, two relay room deviation rectification cylinders in the upper left direction of the deviation rectification relay room are extended to suppress the upper left deviation rectification thrust output by the pipe jacking machine. Then, the driving oil pressure of the relay room deviation rectification cylinders and the pipe jacking machine deviation rectification cylinders is removed, so that under the action of the soil pressure of the formation during pipe jacking, the three deviation rectification cylinders automatically retract and reset, and at the same time, the pipe jacking machine automatically resets to the advancing direction of the axis.

[0060] Through this setting method and operation process, during the deviation rectification process, the deviation rectification mechanisms on the two sets of equipment can be combined to the greatest extent, and at the same time, the impact on the jacking formation during the deviation rectification process can be avoided, meeting the stability of the jacking formation. At the same time, due to the small space of the jacking tunnel, the extrusion stress of the formation soil pressure on the jacking tunnel is more complex. Therefore, dynamic collaborative reset can be better applied to the pipe jacking construction of extra-small hydraulic tunnels, greatly ensuring the safety of construction.

[0061] During the jacking process, the jacking direction of the pipe jacking machine is monitored through the monitoring system, and the jacking direction of the pipe jacking machine is corrected in real time by combining the self-deviation rectification system of the pipe jacking machine and the deviation rectification relay room for the pipe jacking machine.

[0062] Specifically, the monitoring system includes a light target unit, a display and monitoring unit, and a laser emission unit. The light target unit is mainly used to detect the jacking direction of the pipe jacking machine in real time and transmit the jacking data to the display and monitoring unit.

[0063] The light target unit includes a light target sensor arranged at the front end of the machine head shell. The light target sensor is used to receive the laser beam emitted by the laser emission unit to form a laser guiding point. The laser emission unit is installed on the tunnel casing of the jacking entrance. During use, the light target sensor advances in real time following the jacking of the pipe jacking machine, and the display and monitoring unit is used to receive the jacking data with the laser guiding point as a reference and transmit the jacking data to the electric control unit for the operator to refer to and correct the pipe jacking construction system through the electric control unit.

[0064] Specifically, during the jacking process, every 50 m, the laser emission unit is reinstalled. The laser emission unit includes a total station and a level. The total station is used to emit laser, and the level is used to measure the coordinates of the total station and the elevation of the pipe jacking tunnel;

[0065] Both the total station and the level are electrically connected to the electric control unit and are used to transmit the coordinates of the total station, the direction accuracy and distance of the laser beam to the electric control unit.

[0066] The optical target sensor and the electronic control unit that receive the laser beam inside the pipe jacking form the jacking attitude measurement and control system, which is used to measure the vertical and horizontal displacements of the measurement board inside the pipe jacking machine with reference to the laser guiding point of the optical target sensor, the horizontal angle of laser incidence, the elevation angle and the rolling angle of the pipe jacking machine.

[0067] The operator processes the measurement data through long-distance camera monitoring and the microcomputer system, and displays the position deviation of the pipe jacking machine reflected by the processing results on the screen of the display monitoring unit, guiding the operator to carry out the correction operation for the pipe jacking machine.

[0068] In the initial jacking stage, the determination and input of the initial position of the pipe jacking machine include:

[0069] Measure the three data of the elevation angle, rolling angle, and horizontal angle of the measurement board inside the pipe jacking machine, and measure and input the position (X, Y) of the laser reference point relative to the pipe jacking machine 1 into the electronic control unit.

[0070] Install the laser emission system every about 50 meters in the straight section so that the emitted laser beam can be effectively received by the optical target sensor at the front end of the pipe jacking machine. At the same time, manually measure the coordinates (X, Y) of the total station instrument and input them into the electronic control unit as the reference for calculating the position of the pipe jacking machine.

[0071] The laser emission system takes the laser emitted by the total station instrument installed on the inner wall of the tunnel casing as the reference point. Then, the measurement system measures data such as the direction accuracy, distance, and coordinates (X, Y) of the total station instrument of the laser beam and inputs them into the electronic control unit.

[0072] After the laser beam is emitted to the optical target sensor, measure the position (X, Y) of the light spot, calculate the relationship between the axis of the pipe jacking machine and the axis of the laser beam, the elevation angle and the rolling angle of the pipe jacking machine, and transmit the data to the electronic control unit through the cable. The microcomputer in the electronic control unit calculates the result, considers the installation error between the measurement system and the designed axis of the pipe jacking, and calculates the deviation value (X, Y) between the axis of the pipe jacking corresponding to the optical target sensor and the designed axis of the pipe jacking. Through the included angle between the actual axis of the pipe jacking machine and the designed axis of the pipe jacking, predict the (X, Y) deviation trend of the cutting chamber of the pipe jacking machine. Through the data displayed on the operation screen of the pipe jacking machine, the construction personnel can adjust the jacking direction of the pipe jacking machine to make the pipe jacking machine jack along the designed axis, thus ensuring that the accuracy of the jacking direction of the pipe jacking meets the requirements.

[0073] In the present invention, it is determined whether to carry out secondary rectification by the included angle between the jacking direction and the designed axis of the tunnel.

[0074] Specifically, according to the real-time monitoring during the jacking process, when it is detected and judged by the display monitoring unit that the jacking direction deviates from the design axis of the tunnel, it is judged whether the included angle between the jacking direction and the design axis of the tunnel is less than the deviation threshold. If it is less than the deviation threshold, the jacking direction of the pipe jacking machine is directly corrected through the deviation correction oil cylinder of the pipe jacking machine. When the corrected jacking direction returns to the design axis of the tunnel and then deviates from the design axis of the tunnel under the continuous action of the deviation correction push, the driving oil pressure of the deviation correction oil cylinder of the pipe jacking machine is removed. Under the double extrusion of the main jacking force and the front-end formation soil pressure, the offset jacking direction of the pipe jacking machine coincides with the design axis, and the deviation correction oil cylinder of the pipe jacking machine is pressed to reset, ending the deviation correction.

[0075] If it is detected and judged that the included angle between the jacking direction and the design axis of the tunnel is greater than the deviation threshold, first, the jacking direction of the pipe jacking machine is corrected through the deviation correction oil cylinder of the pipe jacking machine. When the corrected jacking direction returns to the design axis of the tunnel and then deviates from the design axis of the tunnel under the continuous action of the deviation correction push, the deviation correction oil cylinder of the relay jack corresponding to the position of the deviation correction oil cylinder of the pipe jacking machine is started to suppress the offset jacking direction after the pipe jacking machine is corrected. At the same time, the driving oil pressures of the deviation correction oil cylinder of the relay jack and the deviation correction oil cylinder of the pipe jacking machine are removed. Under the double extrusion of the main jacking force and the front-end formation soil pressure, the offset jacking direction of the pipe jacking machine is reset to coincide with the design axis, and the deviation correction oil cylinder of the relay jack and the deviation correction oil cylinder of the pipe jacking machine are pressed to reset, ending the deviation correction.

[0076] The judgment on whether to perform secondary deviation correction in this application is mainly based on the fact that the deviation correction oil cylinder of the relay jack and the deviation correction oil cylinder of the pipe jacking machine described above do not retract after the deviation correction jacking, but accompany the reset of the jacking direction of the pipe jacking machine, and then the oil cylinder itself retracts and resets, so that the pipe jacking machine always maintains the contact pressure jacking relationship with the formation, preventing the premise of formation instability.

[0077] Furthermore, the deviation threshold of the included angle between the jacking direction of the pipe jacking machine and the design axis of the tunnel corresponds to the included angle at which, under the state that the deviation correction oil cylinder of the pipe jacking machine outputs the maximum jacking distance, after removing the oil pressure of the deviation correction oil cylinder of the pipe jacking machine, the double extrusion of the main jacking force and the front-end formation soil pressure can make the jacking direction of the pipe jacking machine coincide with the design axis, and the deviation correction oil cylinder of the pipe jacking machine is pressed to reset.

[0078] That is to say, combining the existing oil pressure data of the deviation correction oil cylinder of the pipe jacking machine and the deviation correction oil cylinder of the relay jack, and combining the main jacking force and the front-end formation soil pressure collected during the normal jacking along the tunnel axis, under the state that the deviation correction oil cylinder of the pipe jacking machine outputs the maximum jacking distance, a specific offset included angle can be calculated and determined. And the offset included angle between the jacking direction of the pipe jacking machine and the design axis of the tunnel corresponds to that, under the condition of removing the driving pressure of the deviation correction oil cylinder of the pipe jacking machine, the deviation correction oil cylinder can be reset, and at the same time, when the deviation correction oil cylinder is reset, the jacking direction of the pipe jacking machine exactly coincides with the design axis.

[0079] The calculation of the included angle deviation threshold is mainly based on the pressure reset of the self-oil pressure of the main jacking thrust and the front-end formation earth pressure on the driving pressure of the pipe jacking machine's deviation correction cylinder under the condition of removing the driving pressure of the pipe jacking machine's deviation correction cylinder. At the same time, the jacking distance during the deviation correction process can be determined. It should be noted that the driving pressure of the pipe jacking machine's deviation correction cylinder is the time point after the pipe jacking machine crosses and deviates from the designed axis of the tunnel under the action of the deviation correction thrust, and it is also to provide the distance and spatial adjustment for returning to the tunnel axis again.

[0080] The jacking data during the jacking process is collected in real time through the monitoring system, including the main jacking thrust and the front-end formation earth pressure when the jacking direction of the pipe jacking machine coincides with the designed axis of the tunnel. And through the electronic control unit, according to the collected main jacking thrust, the front-end formation earth pressure, and the oil pressure of the pipe jacking machine's deviation correction cylinder obtained according to the equipment model, it is calculated and determined that when the pipe jacking machine's deviation correction cylinder outputs the maximum jacking distance state, through double extrusion, the jacking direction of the pipe jacking machine can coincide with the designed axis, and the deviation angle of the pipe jacking machine relative to the designed axis when the pipe jacking machine's deviation correction cylinder is compressed and reset is used as the deviation threshold. This is also a corresponding explanation for the above calculation of the included angle deviation threshold.

[0081] During the secondary deviation correction process, through the mutual cooperation of the pipe jacking machine's deviation correction cylinder and the relay jack's deviation correction cylinder, when the jacking direction after deviation correction is away from the designed axis of the tunnel, the relay jack's deviation correction cylinder opposite to the position of the pipe jacking machine's deviation correction cylinder is started to suppress the offset jacking direction after the pipe jacking machine is deviated. Through the dynamic cooperative reset described above, under the double extrusion of the main jacking thrust and the front-end formation earth pressure, the pipe jacking machine's deviation correction cylinder and the relay jack's deviation correction cylinder can be reset. At the same time, during the process of being compressed and reset, the pipe jacking machine is restored to the jacking direction that coincides with the designed axis of the tunnel.

[0082] Through the deviation correction operation in the present invention, it can ensure that the pipe jacking machine always maintains the contact pressure jacking relationship with the formation, prevent the formation from becoming unstable, avoid the force void at the top of the pipe jacking machine caused by the different active retractions of the deviation correction cylinders at the rear side, and thus reduce the risk of the formation instability during jacking.

[0083] At the same time, due to the small space of the jacking tunnel, the extrusion stress of the formation earth pressure on the jacking tunnel is more complex. Therefore, the dynamic cooperative reset can be better applied to the pipe jacking construction of extra-small hydraulic tunnels, greatly ensuring the safety of the construction.

[0084] In order to ensure the stability of the formation earth pressure and facilitate the smoothness of jacking, during the jacking process, thixotropic slurry is continuously injected through the grouting holes arranged at the tail of the pipe jacking machine and on each section of the tunnel casing. After the jacking construction is completed, secondary supplementary grouting is carried out through the grouting holes.

[0085] The voids are filled by injecting thixotropic slurry synchronously, and secondary supplementary grouting is adopted after the construction to make up for the possible defects caused by the synchronous grouting.

[0086] To reduce the frictional resistance and prevent excessive deformation of the formation, a synchronous grouting method of injecting thixotropic slurry while the pipe jacking machine is tunneling is adopted to fill the voids behind the pipe material when the pipe jacking machine advances forward. After the synchronous injection of thixotropic slurry, not only the frictional resistance is reduced, but also the annular voids around the pipe jacking are filled, and the formation deformation and settlement are controlled. To improve the waterproofness and density of the grouting layer around the pipe material, secondary grouting is supplemented after the construction. The grouting body is filled evenly to form a stable waterproof layer, so as to achieve the purpose of strengthening the waterproofness of the pipe jacking.

[0087] For the jacking-out hole construction, the jacking is stopped before the head of the pipe jacking machine reaches the opening of the receiving well. A receiving base is installed in the receiving well, and the position and elevation of the base should be consistent with the attitude of the pipe jacking machine when it is close to the portal to prevent the head from knocking. And the opening of the receiving well is demolished until the pipe jacking machine completely exits the hole to complete the construction.

[0088] When the pipe jacking machine enters the side of the receiving well, the pipe jacking machine should jack at a uniform speed until it completely exits the receiving well. If there is rich groundwater, the gap between the pipe and the opening is blocked with cotton yarn, and water glass or cement slurry is used to press the water stop after the pipe jacking machine completely exits the hole.

[0089] Through the pipe jacking tunnel construction method in the present invention, it can be adapted to the pipe jacking construction of extra-small hydraulic tunnels and can ensure the stability of the deviation correction process to the greatest extent.

[0090] It should be noted that, without conflict, the features in the embodiments of the present application can be combined with each other.

[0091] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A pipe jacking tunnel construction method, characterized in that: The following steps are involved: Caisson construction, excavation of tunnel jacking working well and receiving well; Cement mixing pile construction, construction of mixing piles around the working well and the opening of the departure well; Pipe jacking construction: install the main jacking device and the pipe jacking machine in the working pit, install a deviation correction relay room at the tail end of the pipe jacking machine, continuously install the tunnel casing along with the jacking of the pipe jacking machine, and install a jacking relay room between multiple consecutive tunnel casings; During the jacking process, the jacking direction of the pipe jacking machine is monitored by the monitoring system, and the jacking direction of the pipe jacking machine is corrected in real time in combination with the jacking machine's own correction system and the correction relay room; Grouting construction: During the pipe jacking construction process, a synchronous grouting method of grouting while excavating is adopted to fill the gap between the tunnel casing and the surrounding strata when the pipe jacking machine moves forward; During the jacking hole construction, the jacking is stopped before the head of the pipe jacking machine reaches the receiving well hole, the receiving base is installed in the receiving well, and the receiving well hole is broken, and the construction is completed after the pipe jacking machine is completely out of the hole.

2. The pipe jacking tunnel construction method according to claim 1, characterized in that: The working well and receiving well are both rectangular caissons. The caisson wall is constructed in sections. The blade foot part is constructed first, and then the well wall part above is constructed. The secondary construction section sinking method is adopted. The caisson sinking adopts excavator to take soil and manual digging of soil to sink. After the caisson construction, two rows of mixing piles are constructed around the entrance and exit of the caisson, with a pile diameter of 60cm, a bite of 20cm, a spacing of 50cm, and a pile length of 12m.

3. The pipe jacking tunnel construction method according to claim 1, characterized in that: The main jacking device includes a rear backrest, a main jacking guide rail, a main jacking cylinder and a main jacking pump station. The pipe jacking machine includes a head shell. After the pipe jacking machine is hoisted and installed in the working well and jacked into the tunnel entrance, a correction relay room is installed at the tail end of the head shell, and then the tunnel casing is installed at the tail end of the correction relay room. During the jacking process, according to the change of the thrust of the main jacking cylinder, the jacking relay room is installed between the casing segments formed by different continuous tunnel casings.

4. The pipe jacking tunnel construction method according to claim 3, characterized in that: The correction relay room includes a plurality of relay room correction cylinders evenly spaced circumferentially, and the pipe jacking machine includes a plurality of pipe jacking machine correction cylinders evenly spaced circumferentially, the number of the relay room correction cylinders is greater than the number of the pipe jacking machine correction cylinders, and two different correction cylinders are staggered in the circumferential direction.

5. The pipe jacking tunnel construction method according to claim 4, characterized in that: The monitoring system includes a light target unit, a display monitoring unit and a laser emitting unit; The optical target unit includes an optical target sensor disposed at the front end of the head housing, the optical target sensor is used to receive the laser beam emitted by the laser emitting unit to form a laser guide point, and the laser emitting unit is installed on the tunnel casing of the top entry hole; The display monitoring unit is used to receive the jacking data with reference to the laser guide point, and transmit the jacking data to the electric control unit for reference by the operator and to correct the jacking construction system through the electric control unit.

6. The pipe jacking tunnel construction method according to claim 4, characterized in that: When the display monitoring unit detects that the jacking direction is far away from the design axis of the tunnel, it is determined whether the angle between the jacking direction and the design axis of the tunnel is less than the deviation threshold. If it is less than the deviation threshold, the jacking direction of the jacking machine is directly corrected by the jacking machine correction cylinder. When the jacking direction after correction is far away from the design axis of the tunnel, the driving oil pressure of the jacking machine correction cylinder is removed. Under the dual squeeze of the main jacking thrust and the front stratum soil pressure, the offset jacking direction of the jacking machine is made to coincide with the design axis, and the jacking machine correction cylinder is pressurized to reset, and the correction is ended. If the detection determines that the angle between the jacking direction and the design axis of the tunnel is greater than the deviation threshold, the jacking direction of the pipe jacking machine is first corrected by the pipe jacking machine correction cylinder. When the jacking direction after correction is away from the design axis of the tunnel, the relay correction cylinder opposite to the position of the pipe jacking machine correction cylinder is started to suppress the offset jacking direction of the pipe jacking machine after correction. At the same time, the driving oil pressure of the relay correction cylinder and the pipe jacking machine correction cylinder is removed. Under the dual squeeze of the main jacking thrust and the front-end stratum soil pressure, the offset jacking direction of the pipe jacking machine is reset to coincide with the design axis, and the relay correction cylinder and the pipe jacking machine correction cylinder are pressurized and reset to end the correction.

7. The pipe jacking tunnel construction method according to claim 4, characterized in that: The angle deviation threshold between the jacking direction of the pipe jacking machine and the design axis of the tunnel corresponds to the angle at which the jacking direction of the pipe jacking machine can coincide with the design axis through the dual squeezing of the main jacking thrust and the front-end stratum soil pressure, and the pressure reset angle of the pipe jacking machine's correcting cylinder after the oil pressure of the correcting cylinder is removed when the pipe jacking machine's correcting cylinder outputs the maximum ejection distance.

8. The pipe jacking tunnel construction method according to claim 4, characterized in that: The monitoring system collects real-time jacking data during the jacking process, including the main jacking thrust and the front-end stratum soil pressure when the jacking direction of the pipe jacking machine coincides with the design axis of the tunnel. The electronic control unit calculates and determines the maximum ejection distance of the pipe jacking machine's correcting cylinder output, the jacking direction of the pipe jacking machine can be made to coincide with the design axis through double extrusion, and the deviation angle of the pipe jacking machine relative to the design axis when the pipe jacking machine's correcting cylinder is pressurized and reset, based on the collected main jacking thrust and the front-end stratum soil pressure, as well as the oil pressure of the pipe jacking machine's correcting cylinder obtained according to the equipment model. The deviation angle is used as the deviation threshold.

9. The pipe jacking tunnel construction method according to claim 5, characterized in that: During the jacking process, the laser emitting unit is re-fixed and installed every 50m. The laser emitting unit includes a total station and a level. The total station is used to emit lasers, and the level is used to measure the coordinates of the total station and the elevation of the jacking tunnel. The total station and the level are both electrically connected to the electronic control unit, and are used to transmit the coordinates of the total station, the direction accuracy of the laser beam, and the distance to the electronic control unit.

10. The pipe jacking tunnel construction method according to claim 4, characterized in that: During the jacking process, thixotropic mud is continuously injected through the grouting holes set at the tail of the jacking machine and on the casing of each section of the tunnel. After the jacking construction is completed, secondary supplementary grouting is carried out through the grouting holes.

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