Large-pipe-diameter long-distance pipe jacking construction method suitable for soft soil area

Abstract

The invention discloses a large-pipe-diameter long-distance pipe jacking construction method suitable for a soft soil area. The large-pipe-diameter long-distance pipe jacking construction method comprises the steps that firstly, preparation is conducted before pipe jacking construction; 2, lowering a first pipe jacking section and assembling the first pipe jacking section to the tail end of the pipe jacking machine; step 3, arranging an anti-torsion device; 4, the jack is started for pipe jacking construction; 5, a retaining device is arranged; 6, the jack is retracted to the initial position; seventhly, one jacking pipe joint is put down, and the jacking pipe joint is assembled to the tail end of the previous jacking pipe joint; eighthly, the retaining device is disassembled; and ninthly, pipe jacking construction is conducted again till pipe jacking construction of the tail pipe jacking section is completed. The device can effectively prevent the pipe jacking machine from retreating, twisting, kowtow and the like when the pipe jacking machine goes out of a hole initially.

Description

Technical Field

[0001] The invention relates to a large-diameter and long-distance jacking pipe construction method suitable for soft soil areas, and belongs to the technical field of jacking pipe construction. Background Art

[0002] The Shaodu Road jacking pipe crosses the Yuyao River from east to west, with a total length of 400m. It uses reinforced concrete pipes with an outer diameter of 4.14m and a buried depth of 6m to 16m along the line. A working well and a receiving well are set up on both sides of the Yuyao River. The outer diameter of the caisson is 13m and the maximum sinking depth reaches 22.5m. Since the working well is close to the Yuyao River embankment, the jacking pipe is buried at a depth of 16m. The soil is a typical soft soil in Ningbo, and the water and soil pressure generated is very strong. Under such environmental conditions, the jacking machine will retreat, twist, and kowtow when it initially exits the hole, thus affecting the quality of the jacking construction.

[0003] Pipe jacking machine retreats: When the pipe jacking machine just comes out of the hole, the negative friction resistance generated by the pipe jacking machine, the pipe sections and the surrounding soil layers is less than the water and soil pressure received by the front end of the pipe jacking machine. When the jack retracts, the pipe jacking machine and the pipe sections will also retreat under the action of water and soil pressure, causing the soil layer in front of the pipe jacking machine to collapse and the ground to sink.

[0004] Pipe jacking torsion: When the pipe jacking machine just comes out of the hole, the negative friction torque generated by the pipe jacking machine, the pipe sections and the surrounding soil layers is smaller than the rotational torque generated by the cutter head at the front end of the pipe jacking machine, causing the tail of the pipe jacking machine to rotate with the cutter head, resulting in tearing and damage to the ventilation pipes, mud discharge pipes, power pipes and lighting facilities in the pipe jacking machine. If it is not controlled, it will further cause the cutter head to cut the soil layer unevenly, causing the safety hazard of soil collapse and the quality problem of the deviation of the pipe jacking section line.

[0005] Pipe jacking head knock: When the pipe jacking machine just comes out of the hole, the weight of the pipe jacking machine is concentrated on the cutter head. If it encounters a soft soil layer, the head of the machine will overturn downward. Summary of the invention

[0006] The purpose of the present invention is to provide a large-diameter and long-distance jacking construction method suitable for soft soil areas to prevent the jacking machine from retreating, twisting, knocking, etc. when initially exiting the hole, thereby completing the jacking work safely, efficiently and economically and improving the quality of the jacking construction.

[0007] In order to achieve the above technical objectives, the present invention will adopt the following technical solutions: A large-diameter and long-distance pipe jacking construction method suitable for soft soil areas comprises the following steps: Step 1: Preparation before pipe jacking construction: Install large-diameter and long-distance pipe jacking construction equipment in the working pit; The large-diameter and long-distance pipe jacking construction device includes a frame, a jack, a track assembly and a pipe jacking machine; Install the frame in the working pit and arrange the track assembly on the frame along the jacking direction; A jack bracket is installed at one end of the frame, so that the jack is installed on the rear backrest constructed on the rear end wall of the working pit through the jack bracket; the other end of the frame is set close to the preset tunnel door construction position on the front end wall of the working pit; The pipe jacking machine is lowered and placed at the front end of the track assembly. After installing and debugging the various components of the pipe jacking machine, the tunnel door is chiseled out at the preset tunnel door construction position on the front end well wall; A force transmission frame is installed at a position of the frame body close to the tunnel portal, and the force transmission frame is connected to the front end well wall around the tunnel portal through a reverse pulling device, and an anti-knock device is installed on the force transmission frame to elastically contact with the tail section / tube section of the jacking machine directly below the anti-knock device; Step 2: Lower the first pipe section and assemble it to the tail end of the pipe jacking machine; Step 3: Arrange an anti-twist device; An anti-twist device is arranged between the tail section of the pipe jacking machine, the first pipe jacking section and the force transmission frame to resist the torque generated by the cutter head of the pipe jacking machine; Step 4: Pipe jacking to the target location: Start the jack to carry out pipe jacking construction to push the first pipe jacking section to the target position; Step 5: Arrange the anti-retraction device: Arrange a stop device between the first pipe jacking section and / or the tail section of the pipe jacking machine and the force transmission frame to prevent the pipe jacking machine and the first pipe jacking section from retreating under the action of water and soil pressure on the front end of the pipe jacking machine when the jack retracts; Step 6: Retract the jack to its initial position: Step 7: Lower the next jacking pipe section and assemble it to the end of the previous jacking pipe section: Step 8: dismantle the arranged backstop device; Step 9: Start the jack again to carry out pipe jacking construction; Before carrying out the pipe jacking construction of step nine, it is necessary to evaluate whether the pipe jacking machine will completely come out of the hole. If the judgment result shows that the pipe jacking machine will completely come out of the hole, before carrying out the pipe jacking construction of step nine, first remove the anti-torsion wing at the tail of the pipe jacking machine, and then add the anti-torsion wing to the pipe jacking section at the rear end of the pipe jacking machine; After the pipe jacking construction is completed, before the jack is retracted to the initial position, it is necessary to arrange a stop device on the pipe section of the pipe jacking in the area where the force transmission frame is located; Repeat steps 7 to 9 until the pipe jacking construction of the tail section is completed, then the outer steel plates of the first section and the tail section can be welded to the pre-buried steel plates of the tunnel portal into a whole to complete the pipe jacking construction.

[0008] Preferably, the anti-pull device includes a plurality of anti-pull rods; during construction, one end of each anti-pull rod is connected to a pre-buried anchoring structure provided on the front well wall, and the other end thereof is fixed to a connecting structure arranged on the frame.

[0009] Preferably, the embedded anchoring structure comprises anchor bars, embedded steel plates and external connecting bars; The anchor bar is anchored in the well wall, one side of the embedded steel plate is welded to the anchor bar, and the other side is welded to the external connecting bar; the anti-tension rod is welded to the external connecting bar; The connection structure comprises a connection plate and a mechanical sleeve; the connection plate is welded and fixed to the frame, and a screw hole is arranged on the connection plate, and the reverse pull rod passes through the screw hole and is tightened and fixed by the mechanical sleeve.

[0010] Preferably, a plurality of stiffening plates are provided on the connecting plate; and a pad is provided between the mechanical sleeve and the connecting plate.

[0011] Preferably, the force transmission frame is U-shaped as a whole; it includes two vertical support columns and a crossbeam, the crossbeam spans above the track assembly, and the two vertical support columns are symmetrically arranged on both sides of the track assembly in the horizontal direction, and the lower end of each vertical support column is fixed to the frame body, and the upper end is connected to the crossbeam.

[0012] Preferably, the frame is divided into several standard sections according to highway transportation standards; two adjacent standard sections are connected by a frame connecting plate; the force transmission frame is constructed by rectangular square tubes, and scissor braces are provided between each rectangular square tube.

[0013] Preferably, the anti-twist device comprises an anti-twist wing and an anti-twist pin; wherein: The pipe jacking machine and / or the pipe jacking section are provided with the anti-twist wing at a position close to the track assembly, the main plate surface of the anti-twist wing is perpendicular to the jacking direction, and the lower side wing plate of the anti-twist wing is overlapped on the track assembly; The lifting holes of the jacking pipe section are equipped with anti-twist pins.

[0014] Preferably, the anti-recoil device comprises an anti-recoil wing; The anti-recoil wings provided for the top pipe section include three types, corresponding to the first to third anti-recoil wings; the top pipe section is provided with the first anti-recoil wing at the top position, the second anti-recoil wing at the middle position, and the third anti-recoil wing at the position close to the track assembly; the upper end of the first anti-recoil wing is welded and fixed to the force transmission frame, and the lower end is welded to the top of the top pipe section; the outer end of the second anti-recoil wing is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the top pipe section at the middle position; the third anti-recoil wing is welded and fixed to the track assembly, and the upper end of the third anti-recoil wing is fixed to the position of the top pipe section close to the track assembly, and the main board surface of the third anti-recoil wing is parallel to the jacking direction; There are three types of anti-recoil wings installed at the tail section of the pipe jacking machine, corresponding to anti-recoil wing A, anti-recoil wing B and anti-recoil wing C, among which: The tail section of the pipe jacking machine is equipped with a backstop wing A at the top position, a backstop wing B at the middle position, and a backstop wing C near the track assembly; the upper end of the backstop wing A is welded and fixed to the force transmission frame, and the lower end is welded to the tail section of the pipe jacking machine, the outer end of the backstop wing B is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the pipe jacking machine at the middle position; the backstop wing C is welded and fixed to the track assembly, and the upper end of the backstop wing C is fixed to the position of the pipe jacking machine close to the track assembly, and the main board surface of the backstop wing C is parallel to the jacking direction.

[0015] Preferably, the anti-head-knocking device comprises a support rod, a spring assembly and an elastic rubber wheel; the upper end of the support rod is connected to the force transmission frame, and the lower end is connected to the elastic rubber wheel through the spring assembly, and the elastic rubber wheel can elastically contact the tail section / pipe section of the pipe jacking machine directly below it.

[0016] Preferably, the spring assembly includes a spring and an upper pressure plate and a lower pressure plate respectively connected to the upper and lower ends of the spring, the upper pressure plate is assembled at the lower end of the support rod, and the elastic rubber wheel is installed below the lower pressure plate; the spring has a plurality of strips evenly distributed between the upper pressure plate and the lower pressure plate.

[0017] Based on the above technical objectives, the present invention has the following advantages over the prior art: The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas described in the present invention can effectively prevent the pipe jacking machine from retreating, twisting, knocking, etc. when initially exiting the hole by configuring an anti-knocking device, an anti-twist device and / or a back-stop device during the construction process at an appropriate construction stage, thereby completing the pipe jacking work safely, efficiently and economically, and improving the quality of the pipe jacking construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of a large-diameter and long-distance pipe jacking construction method applicable to soft soil areas according to the present invention; Figure 2 It is a structural schematic diagram of a large-diameter and long-distance pipe jacking construction device suitable for soft soil areas according to the present invention; Figure 3 It is a plan layout diagram of a large-diameter and long-distance pipe jacking construction device suitable for soft soil areas according to the present invention; Figure 4 It is a cross-sectional layout diagram of a large-diameter and long-distance pipe jacking construction device suitable for soft soil areas according to the present invention; Figure 5 It is the structural diagram of the jacking pipe section; Figure 6It is the interface detail drawing of the jacking pipe section; Figure 7 It is a structural diagram of the anti-pull device; Figure 8 It is a three-dimensional diagram of the anti-pull device; Fig. 9 It is a structural diagram of the anti-retraction device arranged in the jacking pipe section; Fig.10 It is a three-dimensional diagram of the anti-retraction device (the state of the pipe jacking machine exiting the hole); Fig.11 It is a three-dimensional diagram of the anti-retraction device (the state of lowering the pipe section); Fig.12 It is a structural diagram of the anti-twist device arranged in the jacking pipe section; Fig.13 It is a three-dimensional diagram of the anti-twist device (the state of the pipe jacking machine coming out of the hole); Fig.14 It is a three-dimensional diagram of the anti-twist device (tube section lowered state); Fig.15 This is the structural diagram of the anti-kowtow device; Fig.16 It is a three-dimensional picture of the anti-kowtow device.

[0019] In the figure: 1, pipe jacking machine; Ⅰ, track assembly; Ⅰ-1, first track assembly; Ⅰ-2, second track assembly; 121, frame longitudinal beam; 122, frame cross beam; 123, scissors brace; 124, frame support column; 125, guide rail connector; 123, scissors brace; 126, force transmission frame; 2, front end well wall; 3, anti-pull device; 31, stiffening plate; 32, connecting plate; 33, external connecting bar; 34, Anti-pull rod; 35, embedded connecting steel plate b; 36, anchor bar; 37, mechanical sleeve; 38, gasket; 4, track; 5, guide rail; 6, backrest; 7, jack bracket; 8, jack; 9, guide rail stop plate; 10, frame connecting plate; 11, jacking pipe section; 12, main frame; 13, scissor support; 14, anti-knocking device; 141, support rod; 142, elastic rubber wheel; 143, spring; 110, inner connection steel; 111, inner ring embedded steel plate; 112, outer steel plate; 113, grouting hole; 114, grouting hole; 115, hoisting hole; 116, anti-retraction wing; 1161, first anti-retraction wing; 1162, second anti-retraction wing; 1163, third anti-retraction wing; 117, anti-twist wing; 118, outer ring embedded steel plate; 119, anti-twist pin; 1190. Positioning anchoring bars; 1191. Polysulfide sealant; 1192. Positioning steel ring; 1193. Sealing ring; 1194. Socket side; 1195. Pine wood pad; 1196. Internal connecting steel; 1197. Embedded connecting steel plate a; 1198. Anchoring bars; 1199. Socket side. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means any limitation to the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise specified, the relative arrangement, expressions and numerical values ​​of the components and steps described in these embodiments do not limit the scope of the present invention. The techniques, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but in appropriate cases, the techniques, methods and equipment should be regarded as part of the specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0021] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations).

[0022] The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas of the present invention is as follows: Figure 1 As shown, the specific steps include: Step 1: Preparation before pipe jacking construction: Step 1.1: The construction of the working well and the receiving well is completed, the site is arranged during the pipe jacking construction phase, and the cement mixing pile wall in front of the well is injected and reaches the designed strength.

[0023] Step 1.2: After the pipe segments are prefabricated at the site and meet the design requirements and pass the inspection, they are transported to the site.

[0024] Step 1.3: Carry out rear backrest construction in the working pit.

[0025] Step 1.4: Build a large-diameter and long-distance pipe jacking construction device in the working pit: For large diameter and long distance pipe jacking construction equipment, please refer to the attached Figure 2-16 As shown, it includes a frame, a jack, a track assembly and a pipe jacking machine; like Figure 2 As shown, the frame is installed in the working shaft, and the track assembly is arranged on the frame along the jacking direction. The frame is constructed by the frame longitudinal beams and the frame cross beams. There are two groups of track assemblies arranged on the frame, corresponding to the first track assembly and the second track assembly. A jack bracket is installed at one end of the frame to install the jack through the jack bracket to the rear backrest constructed on the rear end wall of the working shaft; the other end of the frame is set close to the preset portal construction position on the front end wall of the working shaft; The track assembly includes a guide rail and a track, and the track is arranged on the guide rail, and the guide rail is installed on the crossbeam of the frame through a guide rail connecting plate. The frame of the present invention is divided into three levels for arranging the guide rail and the track according to the different outer diameters of the top pipe sections. The top pipe section outer diameter of 0.9m~1.5m is the first level; the top pipe section outer diameter of 1.8m~3.3m is the second level; the top pipe section outer diameter of 3.5m~4.2m is the third level. In other words, the present invention has three groups of guide rail connecting plates arranged on the frame, corresponding to the first to third guide rail connecting plates, wherein: the first guide rail connecting plate is suitable for the third level top pipe section outer diameter arrangement, the second guide rail connecting plate is suitable for the second level top pipe section outer diameter arrangement, and the third guide rail connecting plate is suitable for the first level top pipe section outer diameter arrangement. Please refer to the attached Figure 2-4 、15.

[0026] like Figure 3 As shown, the frame is divided into several standard segments according to highway transportation standards; two adjacent standard segments are connected by frame connecting plates; the force transmission frame is formed by rectangular square tubes, and scissor braces are arranged between each rectangular square tube.

[0027] The pipe jacking machine is lowered and placed at the front end of the track assembly. After installing and debugging the various components of the pipe jacking machine, the tunnel door is chiseled out at the preset tunnel door construction position on the front end well wall; A force transmission frame is installed at a position of the frame body close to the tunnel portal, and is connected to the front end well wall around the tunnel portal through a back-pull device. At the same time, an anti-knock device is installed on the force transmission frame to elastically contact the tail section / tube section of the jacking machine directly below the anti-knock device.

[0028] like Figure 2 As shown, the force transmission frame is U-shaped as a whole; it includes two vertical support columns and a crossbeam, the crossbeam spans above the track assembly, and the two vertical support columns are symmetrically arranged on both sides of the track assembly in the horizontal direction, and the lower end of each vertical support column is fixed to the frame body, and the upper end is connected to the crossbeam.

[0029] like Figure 5 , Figure 6 As shown, the pipe section of the present invention adopts C50P10 reinforced concrete pipe, which is divided into the first and last pipe sections according to the needs of the jacking project ( Figure 5 a) and standard pipe section ( Figure 5 b) in the figure. A circle of steel plates will be embedded in the outer side of the first and last sections. When the jacking pipe is in place, the steel plates and the steel ring of the tunnel gate will be welded into a whole, which can effectively prevent water leakage. In addition, when the jacking machine exits the tunnel, the outer steel plate can accommodate more anti-retraction wings and anti-torsion wings. In the standard section, there is no outer steel plate, and the sealing ring at the interface of the pipe section is used to stop the water, and a circle of water-stop steel ring is welded on the embedded steel plate of the inner circle of the pipe section to stop the water (the three sections of the front and rear sections of the jacking pipe are welded with internal connecting steel to increase the integrity of the pipe section. When the jacking pipe is in place, it will be removed and a circle of water-stop steel ring will be welded to stop the water).

[0030] The anti-pull device is one of the important structures connecting the frame and the front end of the well wall. Its main function is to resist the water and soil pressure transmitted from the front of the pipe jacking machine and provide certain anti-torsion and anti-overturning functions. Figure 5-7 As shown, it includes several anti-pull rods; one end of the anti-pull rod is connected to the front well wall through a pre-buried anchoring structure, and the other end is fixed to the frame through a connecting structure. The pre-buried anchoring structure includes anchor bars, pre-buried steel plates and external connecting bars; the anchor bars are anchored in the well wall, one side of the pre-buried steel plate is welded and fixed to the anchor bars, and the other side is welded to the external connecting bars; the anti-pull rod is welded and fixed to the external connecting bars; the connecting structure includes a connecting plate and a mechanical sleeve; the connecting plate is welded and fixed to the frame, and a screw hole is set on the connecting plate, and the anti-pull rod passes through the screw hole and is tightened and fixed by the mechanical sleeve. A triangular stiffening plate is set around the connecting plate to prevent the connecting plate from local buckling under the action of the anti-pull rod.

[0031] like Fig.15 , 16 As shown, the anti-knocking device includes a support rod, a spring assembly and an elastic rubber wheel; the upper end of the support rod is connected to the force transmission frame, and the lower end is connected to the elastic rubber wheel through the spring assembly, and the elastic rubber wheel can elastically contact the tail section / pipe section of the jacking machine directly below it. The spring assembly includes a spring and an upper pressing plate and a lower pressing plate respectively connected to the upper and lower ends of the spring, the upper pressing plate is assembled at the lower end of the support rod, and the elastic rubber wheel is installed below the lower pressing plate; the spring has a plurality of strips, which are evenly distributed between the upper pressing plate and the lower pressing plate.

[0032] The anti-knock device can be adjusted to different heights according to the size of the pipe section. The lower end of the anti-knock device is a roller structure whose rolling direction is consistent with the jacking direction. When the pipe jacking machine overturns downward (knocks) after leaving the hole, the device provides directional jacking force to prevent it from overturning (knocks).

[0033] When the pipe jacking machine knocks its head, the tunnel gate is usually used as a prying point, and the cutter disc drives the head of the pipe jacking machine to tilt downward, and the tail of the pipe jacking machine to tilt upward. The elastic wheel installed on the force transmission frame can effectively prevent the tail from tilting upward.

[0034] Building a large-diameter and long-distance pipe jacking construction device in the working pit specifically includes the following steps: Step 1.4.1. Use a crane to lower each standard segment of the frame one by one and connect each standard segment together through the frame connecting plate with bolts to form a frame, and weld the bottom of the frame to the embedded steel plate of the well bottom plate.

[0035] Step 1.4.2, lower the jack bracket and weld it to the rear end of the frame. The jack brackets are connected by steel sections.

[0036] Step 1.4.3: Select a position that matches the outer diameter of the top pipe to install the track assembly: weld the track to the guide rail, and connect the guide rail to the frame crossbeam with bolts.

[0037] Step 1.4.4: Install a calibrated jack and test it. The jack should be close to the rear backrest.

[0038] Step 1.4.5: Lower all parts of the pipe jacking machine and install and test them, and chisel out the tunnel door; Step 1.4.6: Install the force transmission frame, the anti-pull device, and the anti-knocking device to complete the preparations for pipe jacking construction.

[0039] Step 2: Lower the first pipe section and assemble it to the tail end of the pipe jacking machine; The pipe jacking section adopts C50P10 reinforced concrete pipe, which is divided into two types according to the needs of the pipe jacking project: the head and tail pipe jacking sections and the standard section pipe jacking sections. The head and tail pipe jacking sections will have a circle of steel plates embedded on the outside. When the pipe jacking is in place, the steel plates and the steel ring of the tunnel gate will be welded into a whole, which can effectively prevent water leakage; in addition, when the pipe jacking machine exits the tunnel, the outer steel plate can accommodate more anti-retraction wings and anti-torsion wings. In the standard section pipe jacking section, there is no outer steel plate, and the sealing ring at the pipe section interface is used to stop water, and a circle of water-stop steel ring is welded on the embedded steel plate on the inner circle of the standard section pipe jacking section to stop water (the front and rear three sections of the pipe jacking are welded with internal connecting steel to increase the integrity of the pipe jacking section. When the pipe jacking is in place, it is removed and a circle of water-stop steel ring is welded to stop water).

[0040] Step 3: Arrange an anti-twist device; When the pipe jacking machine just comes out of the hole, the negative friction torque generated by the pipe jacking machine and the pipe joints and the surrounding soil layers is less than the rotation torque generated by the cutter head at the front end of the pipe jacking machine, causing the tail of the pipe jacking machine to rotate with the cutter head, resulting in tearing and damage to the ventilation pipes, mud pipes, power pipes and lighting facilities in the pipe jacking machine. If not controlled, it will further cause the cutter head to cut the soil layer unevenly, causing the safety hazard of soil collapse and the quality problem of pipe joint line deviation. In order to avoid the twisting of the pipe jacking machine, the present invention innovatively proposes an anti-twist device, which is divided into the pipe jacking machine exiting the hole state and the pipe joint installation state according to the pipe jacking construction state.

[0041] When the pipe jacking machine is in the hole exiting state, in order to resist the torque generated by the cutter head of the pipe jacking machine, several symmetrical anti-twist wings A are welded on the outer steel body of the pipe jacking machine and contact the track assembly. When the cutter head drives the pipe jacking machine body to twist, the anti-twist wings A will firmly "stuck" the track assembly. For details, please refer to the attached Fig.13 .

[0042] When the pipe segment is installed, the anti-twist wing B is welded on the outer steel plate of the first jacking pipe segment. At the same time, two anti-twist pins are set on its lifting hole and welded to the reaction frame. The reaction frame and the working well are used to resist the torque of the cutter head. For details, please refer to the attached Fig.12 , Fig.14 At this time, the anti-twist device of the first jacking pipe section includes an anti-twist wing B and an anti-twist pin; the main plate surface of the anti-twist wing B is perpendicular to the jacking direction, and the lower wing plate of the anti-twist wing B is overlapped on the track assembly; the anti-twist pin is installed in the hoisting hole of the jacking pipe section. The anti-twist pin is welded and fixed on the force transmission frame, and the length extension direction of the anti-twist pin is perpendicular to the jacking direction to achieve the anti-twist function. The anti-twist wing A and the anti-twist wing B are made of 20mm thick steel plates. The anti-twist pin is made of square tube.

[0043] Before the pipe jacking machine completely enters the tunnel, the anti-twist wings on the pipe jacking machine are cut off and anti-twist wings are added to the subsequent pipe jacking sections.

[0044] In addition, in order to increase the torsion resistance, the pipe jacking machine and the pipe jacking section are connected as a whole with internal connecting steel. The pipe sections are also connected as a whole with internal connecting steel, and the inner wall of each pipe section close to the pipe mouth is provided with an embedded steel plate as a welding carrier for the internal connecting steel.

[0045] An anti-twist device is arranged for the jacking pipe section and the tail section of the jacking machine in the area covered by the force transmission frame. Specifically, an anti-twist device is arranged between the first jacking pipe section and / or the tail section of the jacking machine and the force transmission frame to resist the torque generated by the cutter disc of the jacking machine.

[0046] Step 4: Pipe jacking to the target location: Start the jack to carry out pipe jacking construction to push the first pipe jacking section to the target position; Step 5: Arrange the anti-retraction device: A stop device is arranged between the first jacking pipe section and / or the tail section of the jacking machine and the force transmission frame to prevent the jacking machine and the jacking pipe section from retreating under the action of water and soil pressure at the front end of the jacking machine when the jack retracts.

[0047] When the pipe jacking machine just comes out of the hole, the negative friction resistance generated by the pipe jacking machine, the first pipe section and the surrounding soil layer is less than the water and soil pressure received by the front end of the pipe jacking machine. When the jack retracts, the pipe jacking machine and the first pipe section will also retreat under the action of water and soil pressure, causing the soil layer in front of the pipe jacking machine to collapse and the ground to settle. The pipe jacking hole is an important node in the pipe jacking project and also a major risk source.

[0048] In order to increase the safety of the tunnel portal when chiseling and the pipe jacking machine exiting the tunnel, a cement mixing pile wall is usually set up within 5m outside the tunnel portal. According to the Rankine soil pressure formula, the self-stability of the cement mixing pile wall is much greater than the self-stability of the original soil layer. When the pipe jacking machine just exits the tunnel, it is still inside the cement mixing pile wall. The cutter head of the pipe jacking machine is basically not subject to water and soil pressure, and the number of stop wings required is relatively small. When the pipe jacking machine passes through the cement mixing pile wall, the original water and soil pressure on the cutter head will increase explosively, so the number of stop wings required is relatively large.

[0049] Specifically, the anti-recoil device includes an anti-recoil wing; Figure 9-11 As shown, the anti-retreat wings equipped for the first pipe section include three types, corresponding to the first to third anti-retreat wings; the first pipe section is equipped with the first anti-retreat wing at the top position, the second anti-retreat wing at the middle position, and the third anti-retreat wing near the track assembly; the upper end of the first anti-retreat wing is welded and fixed to the force transmission frame, and the lower end is welded to the top of the first pipe section; the outer end of the second anti-retreat wing is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the first pipe section at the middle position; the third anti-retreat wing is welded and fixed to the track assembly, and the upper end of the third anti-retreat wing is fixed to the position of the first pipe section close to the track assembly, and the main board surface of the third anti-retreat wing is parallel to the jacking direction.

[0050] like Fig. 9 , Fig.11 As shown, the anti-recoil wing equipped with the pipe jacking machine includes two types, corresponding to anti-recoil wing A, anti-recoil wing B and anti-recoil wing C; the tail section of the pipe jacking machine is equipped with anti-recoil wing A at the top position, anti-recoil wing B at the middle position, and anti-recoil wing C near the track assembly. The upper end of the anti-recoil wing A is welded and fixed to the force transmission frame, and the lower end is welded to the tail section of the pipe jacking machine. The outer end of the anti-recoil wing B is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the tail section of the pipe jacking machine at the middle position; the anti-recoil wing C is welded and fixed to the track assembly, and the upper end of the anti-recoil wing C is fixed to the position of the pipe jacking machine near the track assembly, and the main board surface of the anti-recoil wing C is parallel to the jacking direction.

[0051] Step 6: Retract the jack to its initial position: Step 7: Lower the next jacking pipe section and assemble it to the end of the previous jacking pipe section: Lower the next pipe section, start the jack to make the next pipe section close to the previous pipe section, weld the inner connecting steel between the two pipe sections, and then complete the connection and fixation between the two pipe sections.

[0052] Step 8: dismantle the arranged backstop device; In view of the fact that the components of the anti-recoil device in the present invention (the anti-recoil wing and the anti-recoil pin) are fixed by welding, when disassembling the arranged anti-recoil device, it is sufficient to cut it off. However, for the anti-recoil pin, in addition to cutting it off from the force transmission frame, it is also necessary to pull it out from the lifting hole.

[0053] Step 9: Start the jack again to carry out pipe jacking construction; Start the jack again and continue to push the pipe jacking machine and pipe sections into the soil.

[0054] In fact, when the anti-recession wings and anti-torsion wings are deployed, they are all carried out on the jacking pipe sections and the tail section of the jacking machine in the force transmission frame area.

[0055] Before carrying out the pipe jacking construction of step nine, it is necessary to evaluate whether the pipe jacking machine will completely come out of the hole. If the judgment result shows that the pipe jacking machine will completely come out of the hole, before carrying out the pipe jacking construction of step nine, first remove (cut off) the anti-twist wing at the tail of the pipe jacking machine, and then add the anti-twist wing to the pipe jacking section at the rear end of the pipe jacking machine; After the pipe jacking construction is completed, before the jack is retracted to the initial position, it is necessary to arrange a stop device on the pipe section of the pipe jacking in the area where the force transmission frame is located; Repeat steps 7 to 9 until the pipe jacking construction of the tail section is completed, then the outer steel plates of the first section and the tail section can be welded to the pre-buried steel plates of the tunnel portal into a whole to complete the pipe jacking construction.

Claims

1. A large-diameter and long-distance pipe jacking construction method suitable for soft soil areas, characterized in that: The steps include: Step 1: Preparation before pipe jacking construction: Install large-diameter and long-distance pipe jacking construction equipment in the working pit; The large-diameter and long-distance pipe jacking construction device includes a frame, a jack, a track assembly and a pipe jacking machine; Install the frame in the working pit and arrange the track assembly on the frame along the jacking direction; A jack bracket is installed at one end of the frame, so that the jack is installed on the rear backrest constructed on the rear end wall of the working pit through the jack bracket; the other end of the frame is set close to the preset tunnel door construction position on the front end wall of the working pit; The pipe jacking machine is lowered and placed at the front end of the track assembly. After installing and debugging the various components of the pipe jacking machine, the tunnel door is chiseled out at the preset tunnel door construction position on the front end well wall; A force transmission frame is installed at a position of the frame body close to the tunnel portal, and the force transmission frame is connected to the front end well wall around the tunnel portal through a reverse pulling device, and an anti-knock device is installed on the force transmission frame to elastically contact with the tail section / tube section of the jacking machine directly below the anti-knock device; Step 2: Lower the first pipe section and assemble it to the tail end of the pipe jacking machine; Step 3: Arrange an anti-twist device; An anti-twist device is arranged between the tail section of the pipe jacking machine, the first pipe jacking section and the force transmission frame to resist the torque generated by the cutter head of the pipe jacking machine; Step 4: Pipe jacking to the target location: Start the jack to carry out pipe jacking construction to push the first pipe jacking section to the target position; Step 5: Arrange the anti-retraction device: Arrange a stop device between the first pipe jacking section and / or the tail section of the pipe jacking machine and the force transmission frame to prevent the pipe jacking machine and the first pipe jacking section from retreating under the action of water and soil pressure on the front end of the pipe jacking machine when the jack retracts; Step 6: Retract the jack to its initial position: Step 7: Lower the next jacking pipe section and assemble it to the end of the previous jacking pipe section: Step 8: dismantle the arranged anti-retraction device; Step 9: Start the jack again to carry out pipe jacking construction; Before carrying out the pipe jacking construction of step nine, it is necessary to evaluate whether the pipe jacking machine will completely come out of the hole. If the judgment result shows that the pipe jacking machine will completely come out of the hole, before carrying out the pipe jacking construction of step nine, first remove the anti-torsion wing at the tail of the pipe jacking machine, and then add the anti-torsion wing to the pipe jacking section at the rear end of the pipe jacking machine; After the pipe jacking construction is completed, before the jack is retracted to the initial position, it is necessary to arrange a stop device on the pipe section of the pipe jacking in the area where the force transmission frame is located; Repeat steps 7 to 9 until the pipe jacking construction of the tail section is completed, then the outer steel plates of the first section and the tail section can be welded to the pre-buried steel plates of the tunnel portal into a whole to complete the pipe jacking construction.

2. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 1 is characterized in that: The anti-pull device comprises a plurality of anti-pull rods; during construction, one end of each anti-pull rod is connected to a pre-buried anchoring structure arranged on the front well wall, and the other end thereof is fixed to a connecting structure arranged on the frame.

3. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 2 is characterized in that: The embedded anchoring structure includes anchor bars, embedded steel plates and external connecting bars; The anchor bar is anchored in the well wall, one side of the embedded steel plate is welded to the anchor bar, and the other side is welded to the external connecting bar; the anti-tension rod is welded to the external connecting bar; The connection structure comprises a connection plate and a mechanical sleeve; the connection plate is welded and fixed to the frame, and a screw hole is arranged on the connection plate, and the reverse pull rod passes through the screw hole and is tightened and fixed by the mechanical sleeve.

4. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 3 is characterized in that: A plurality of stiffening plates are arranged on the connecting plate; a pad is arranged between the mechanical sleeve and the connecting plate.

5. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 1 is characterized in that: The force transmission frame is U-shaped as a whole; it includes two vertical support columns and a crossbeam, the crossbeam spans above the track assembly, and the two vertical support columns are symmetrically arranged on both sides of the track assembly in the horizontal direction, and the lower end of each vertical support column is fixed to the frame body, and the upper end is connected to the crossbeam.

6. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 5 is characterized in that: The frame is divided into several standard sections according to highway transportation standards; two adjacent standard sections are connected by frame connecting plates; the force transmission frame is constructed by rectangular square tubes, and scissor braces are arranged between each rectangular square tube.

7. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 1 is characterized in that: The anti-twist device comprises an anti-twist wing and an anti-twist latch; wherein: The pipe jacking machine and / or the pipe jacking section are provided with the anti-twist wing at a position close to the track assembly, the main plate surface of the anti-twist wing is perpendicular to the jacking direction, and the lower side wing plate of the anti-twist wing is overlapped on the track assembly; The lifting holes of the jacking pipe section are equipped with anti-twist pins.

8. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 1 is characterized in that: The anti-recoil device comprises an anti-recoil wing; The anti-recoil wings provided for the top pipe section include three types, corresponding to the first to third anti-recoil wings; the top pipe section is provided with the first anti-recoil wing at the top position, the second anti-recoil wing at the middle position, and the third anti-recoil wing at the position close to the track assembly; the upper end of the first anti-recoil wing is welded and fixed to the force transmission frame, and the lower end is welded to the top of the top pipe section; the outer end of the second anti-recoil wing is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the top pipe section at the middle position; the third anti-recoil wing is welded and fixed to the track assembly, and the upper end of the third anti-recoil wing is fixed to the position of the top pipe section close to the track assembly, and the main board surface of the third anti-recoil wing is parallel to the jacking direction; The backstop wing provided at the tail section of the pipe jacking machine includes three types, corresponding to the backstop wing A, the backstop wing B and the backstop wing C, wherein: the backstop wing A is provided at the top position of the tail section of the pipe jacking machine, the backstop wing B is provided at the middle position, and the backstop wing C is provided near the position of the track assembly; The upper end of the anti-retreat wing A is welded and fixed to the force transmission frame, and the lower end is welded to the tail section of the pipe jacking machine. The outer end of the anti-retreat wing B is welded and fixed to the force transmission frame, and the inner end is welded to the outer wall of the pipe jacking machine in the middle position; the anti-retreat wing C is welded and fixed to the track assembly, and the upper end of the anti-retreat wing C is fixed to the position of the pipe jacking machine close to the track assembly, and at the same time, the main board surface of the anti-retreat wing C is parallel to the jacking direction.

9. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 1 is characterized in that: The anti-head-knocking device includes a support rod, a spring assembly and an elastic rubber wheel; the upper end of the support rod is connected to the force transmission frame, and the lower end is connected to the elastic rubber wheel through the spring assembly. The elastic rubber wheel can elastically contact the tail section / pipe section of the pipe jacking machine directly below it.

10. The large-diameter and long-distance pipe jacking construction method suitable for soft soil areas according to claim 9, characterized in that: The spring assembly includes a spring and an upper pressure plate and a lower pressure plate respectively connected to the upper and lower ends of the spring. The upper pressure plate is assembled at the lower end of the support rod, and the elastic rubber wheel is installed below the lower pressure plate. The spring has a plurality of strips evenly distributed between the upper pressure plate and the lower pressure plate.

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