CN112012757B

CN112012757B - Muddy water balance type pipe jacking machine and construction process thereof in flowing sand stratum

Info

Publication number: CN112012757B
Application number: CN202010965654.3A
Authority: CN
Inventors: 王涛; 马建军; 赵玉阔; 左彦涛; 刘金
Original assignee: Linyi Municipal Group Co Ltd
Current assignee: Linyi Municipal Group Co Ltd
Priority date: 2020-09-15
Filing date: 2020-09-15
Publication date: 2022-02-25
Anticipated expiration: 2040-09-15
Also published as: CN112012757A

Abstract

The invention discloses a muddy water balanced type push bench which comprises a machine head, a main jacking mechanism, a hydraulic station, a deviation rectifying oil cylinder, a control cabinet and a laser theodolite, wherein the main jacking mechanism is arranged on the machine head; the machine head comprises a cutter head, a drilling cutter holder, an adjusting hoop, a center cutter, a fixed hoop, a material guiding hole, a front bin and a driving part; the hydraulic station, the deviation-rectifying oil cylinder and the control cabinet are positioned in a front cabin of the machine head; the cutter head is fixed at the top end of the front bin; the drilling tool apron and the central tool are fixed on the cutter head; the fixed hoop and the adjusting hoop are fixed on the outer wall of the front bin and are positioned on one side of the cutter head; the driving part is positioned in the front bin and on one side of the cutter head; the material guiding port is positioned on one side of the driving part, and the driving part is provided with a driving motor. Aiming at the quicksand rock mixed layer encryption, the number of shell cutters on the cutter head is enhanced, and the drilling capability is improved; and the deformed steel bars are connected with the connecting steel pipes in series, so that the possibility of interface water seepage during deviation correction is reduced.

Description

Muddy water balance type pipe jacking machine and construction process thereof in flowing sand stratum

Technical Field

The invention belongs to the technical field of road construction, and particularly relates to a muddy water balanced type pipe jacking machine.

Background

With the rapid development of society, the urbanization process is faster and faster, and various urban infrastructures are also in fierce and vigorous construction; such as underground pipeline construction; in the past, a method of excavating and embedding on the ground is generally adopted, and at present, the method of excavating on the ground is mostly replaced by pipe jacking construction.

The pipe-jacking construction is a pipe burying construction technology without excavation or with less excavation, working wells and receiving wells are excavated at two ends of a project, main jacking equipment is arranged in the working wells, the friction force between the pipes and the surrounding soil is overcome through the thrust of the main jacking equipment, the pipes are jacked into the receiving wells according to the designed gradient, and earthwork is transported away in the excavation process; after the pipe of one section is pushed into the soil layer, the pipe of the second section is pushed into the soil layer continuously; the following problems occur in the existing construction process:

1) when the pipe top reaches the bottom of the river bed and the height difference is small, the soil pressure cannot be reached, the machine head is easy to deflect upwards in the jacking process, the self-carrying deviation rectification of the equipment cannot be solved, and the jacking construction requirement cannot be met;

2) large-particle-size isolated rock blocks and shale layers exist in the stratum, so that the pipe jacking machine is difficult to drill and low in construction efficiency;

3) when the pipe jacking machine head is used for correcting deviation, water seepage or uneven stress caused by local staggered opening of pipeline connection can occur.

Disclosure of Invention

Aiming at overcoming the defects in the prior art, the invention provides the mud balanced push bench, which strengthens the number of shell cutters on a cutter head aiming at the encryption of a quicksand rock mixed layer and improves the drilling capability; the deformed steel bars are connected in series with the connecting steel pipes, so that the possibility of interface water seepage during deviation correction is reduced;

in order to achieve the purpose, the invention adopts the technical scheme that:

a muddy water balance type pipe jacking machine comprises a machine head, a main jacking mechanism, a hydraulic station, a deviation rectifying oil cylinder, a control cabinet and a laser theodolite; the machine head comprises a cutter head, a drilling cutter holder, an adjusting hoop, a center cutter, a fixed hoop, a material guiding hole, a front bin and a driving part; the hydraulic station, the deviation-rectifying oil cylinder and the control cabinet are positioned in a front bin of the machine head; the cutter head is fixed at the top end of the front bin; the drilling tool apron and the central tool are fixed on the cutter head; the fixed hoop and the adjusting hoop are fixed on the outer wall of the front bin and are positioned on one side of the cutter head; the driving part is positioned in the front bin and on one side of the cutter head; the material guiding port is positioned on one side of the driving part, and the driving part is provided with a driving motor.

The cutter head is provided with a cutter groove I and a cutter groove II; the drilling tool apron and the central tool are respectively fixed in the tool groove I and the tool groove II; the drilling and milling cutter seat is provided with a plurality of drilling and milling cutters and shell cutters, the drilling and milling cutters are positioned on two sides of the drilling and milling cutter seat and have opposite drilling directions, and the shell cutters and the drilling and milling cutters are fixed in a staggered manner; and (5) encrypting and strengthening the number of the shell knives.

The adjusting hoop comprises a fixing ring and an adjusting plate; two rows of mounting grooves are circumferentially arranged on the outer wall of the fixing ring and are arranged in a staggered manner; the adjusting plate is fixed in the mounting groove; guide grooves I are formed in two ends of the mounting groove; the adjusting plate comprises a blocking plate I, a blocking plate II, a guide rod III, a spring I and a spring II; the baffle plate I is internally provided with a cavity, one end of the outer part of the baffle plate I is provided with a guide block I, the other end of the baffle plate I is provided with a fixed block, a guide rod I is arranged in the cavity, and the outer side surface of the baffle plate I is provided with a guide block II; the guide rod III is fixed on the fixed block; the spring I is sleeved with a guide rod III; the inner part of the baffle plate II is a cavity and is sleeved with the baffle plate I, a guide rod II is fixedly arranged in the baffle plate II, a guide groove II matched with a guide block II is formed in the side wall of the baffle plate II, two ends of the spring II are respectively sleeved with the guide rod II and the guide rod I, and one end of the baffle plate II is provided with a guide block III; the adjusting plate is pushed to slide along the guide groove I through the elasticity of the spring I, and the guide block III and the guide block I are arranged in the guide groove I; when the adjusting plate is stressed and retracted, the spring II is extruded and contracted by the blocking plate I and the blocking plate II, and the guide block II slides along the guide groove II; the fixed hoop is positioned on one side of the adjusting hoop.

The driving motor of the driving part provides power to drive the cutter head to rotate for drilling movement; guiding and measuring the drilling advancing direction of the machine head through a laser theodolite; a plurality of deviation rectifying oil cylinders are circumferentially arranged in the front bin, and the deviation rectifying oil cylinders in corresponding positions and directions are controlled to eject out to adjust the drilling directions through a hydraulic station when the deviation occurs in different drilling directions.

The slurry stirring mechanism comprises a stirring pump, a sludge conveying pump and a sludge conveying pipe; the mud feeding pipe is connected with a feed inlet; the mud sedimentation mechanism comprises a mud pump and a mud pipe, and the mud pipe is connected with the feed inlet.

A track, a supporting steel sheet pile and a main jacking mechanism are arranged in the working well; the track supports the pipeline, and the pipeline top is pushed into the culvert through the main top mechanism; the pipeline is internally provided with a steel belt, and the pipeline is connected with the deformed steel bar into a whole by welding through the steel belt in series connection.

A construction process of a muddy water balance type pipe jacking machine in a quicksand stratum comprises the steps of early construction preparation; debugging and installing equipment; jacking construction; dismantling equipment; a water-closing test; the method comprises the following specific steps:

1. preparation in the early stage of construction: comprises the steps of customizing a pipeline; building a receiving well and a construction well; the machine head is improved; wherein the pipeline adopts an autonomously improved customized pipe; constructing reinforced concrete back walls at the bottoms of the receiving well and the construction well, and constructing support steel sheet piles at the middle upper part; in addition, the number of the shell knives is encrypted and strengthened.

2. Equipment debugging and installation: the laser theodolite, the track, the main jacking equipment and the machine head are fixedly arranged; a guardrail enclosure is additionally arranged on a construction site, an upper escalator and a lower escalator are arranged in a construction well, and a mud preparation pool, a material equipment and pipe storage warehouse, a construction temporary access way, a construction rest area and the like are arranged on the periphery of the construction well; sequentially installing various devices and systems; the system comprises a main jacking system, a grouting and discharging system, a power supply arrangement and the like, wherein after all equipment systems are installed, trial operation debugging and safety inspection before hole exit are carried out until jacking operation is carried out after the equipment systems are qualified.

3. And (3) jacking construction:

after all the equipment is completely checked, firstly, a first section of pipe is hung, a water outlet pipe, a mud pipe and other various water circuit lines are connected, after the first section of pipe is jacked in until the first section of pipe is finished, the jack is retracted, various pipelines and water and power circuits are disassembled, then, a section of pipe is hung down, various water pipes, mud pipes and other water and power circuits are reconnected, jacking is continued, and circulation is performed according to examples; grouting the head and the side wall through a grouting pump and a pipeline in the jacking process, forming a complete annular slurry lubricating sleeve between the outer wall of the pipe and a soil layer, changing the original dry friction state into a liquid friction state, synchronously grouting the head end and the tail end of the pipe jacking machine along with the jacking of the pipeline in the process, and tracking and supplementing the slurry at a proper position of a concrete pipeline; measuring and correcting deviation according to design requirements in the jacking process; when the construction section passes through a river channel, the pressure of the soil body reaches the requirement of a jacking pipe by adopting a cofferdam soil body prepressing mode; internal thread steel in the range of 18mm-25mm is welded and connected with the pipe in series while the pipe is pushed; and after the pipe jacking is finished, sequentially disassembling the construction equipment according to the construction rules and then transporting the construction equipment out of the construction site.

1) Establishing a ground and underground measurement control system according to a set pipeline central line and a set working pit position; setting a temporary level point introduced from a ground level point in the jacking pit, correcting and adjusting the elevation of an instrument during shift switching, introducing a jacking axis into the pit from the center of a designed pipeline through a theodolite, and then performing centering observation; the initial jacking working well enters the soil layer, and the measurement is not less than 1 time when the initial jacking working well is jacked for 30 cm; during normal jacking, the measurement is not less than 1 time per 1m of jacking; and the measurement should be increased 30m before entering the receiving working well, and the measurement should not be less than 1 time for every 30cm of jacking.

2) Grouting: grouting the machine head and the side wall through a grouting pump and a pipeline, forming a complete annular slurry lubricating sleeve between the outer wall of the pipe and a soil layer, and changing the original dry friction state into a liquid friction state; in the process, the mud jacking at the tail end of the pipe jacking machine head is synchronously mud jacking along with the jacking of the pipeline, and tracking and mud supplementing are carried out at a proper position of the concrete pipeline.

The mud components comprise bentonite, alkaline inorganic matters, polyacrylamide and water; wherein, the mass ratio of bentonite: basic inorganic substances: polyacrylamide: water (300-; the alkaline inorganic substance is sodium carbonate or sodium hydroxide or a compound of the sodium carbonate and the sodium hydroxide; among them, preferred is the bentonite: the alkaline inorganic substance: the polyacrylamide: 380kg of water, 6kg of water, 1.3kg of water and 810kg of water; the mud stirring time is 150-200s, the stirring speed is 280-320r/min, and the grouting pressure is 0.2-0.4 MPa; in the present invention, it is preferable that the stirring time is 180s, the stirring rate is 300r/min, and the grouting pressure is 0.35 MPa.

3) Cofferdam soil body pre-compaction: when the height difference from the machine head to the bottom of the river bed is lower or less than 1 m; piling and covering soil above the pipeline along the way by an excavator; the soil body overburden thickness is 1.5-2m, the width is 1.5-2m larger than the diameter of the pipe material of the jacking pipe, and two sides are evenly distributed by taking the central axis of the jacking pipe as a reference; in the cofferdam soil body compaction process, a half cofferdam construction mode is adopted, namely after the construction is finished on the left side of the river channel, soil body prepressing and pipe jacking construction are carried out on the right side of the river channel, and then the prepressed soil body on the left side is removed to ensure the smoothness of the river channel;

4) entering a hole: when the pipe jacking machine head enters the hole, a pillow and a roller are pre-arranged in the receiving pit, and when the front part of the pipe jacking machine is close to the outer edge of the receiving pit, a sealing door is removed; the length of the reserved pipe joint is considered after the pipe joint is jacked into the receiving pit, so that pipe disassembly is avoided as much as possible, construction of a connector is facilitated, and the length of the exposed pipe section is less than one third of the length of the pipe.

5) Pipeline concatenation and waterproof: uniformly coating a liquid lubricant on the inner surface of the socket, then respectively sleeving rubber rings on the sockets, coating the liquid lubricant, and welding and connecting the pipes into a whole by adopting internal thread steel in a range of 18-25mm through a series connection steel belt, wherein the preferred threaded steel is 20 mm; and (3) taking water stopping measures at a pipeline interface in the jacking process: firstly, sealing a rubber ring at the connecting position of a steel socket port interface; secondly, a river-crossing special pipeline is customized, and a groove sealing interface is reserved at the position of the socket; thirdly, after the pipe jacking is finished, the inner side of the interface is processed by adopting asbestos cement to prepare an interface pipe belt; if there is some water seepage after three-layer water-proofing treatment, the leakage-stopping quick-setting agent without water leakage is used to quickly stop water.

4. Water-closing test: cleaning up the inspection well before irrigation; for the reserved holes, the pre-buried pipe orifices, the inlet and the outlet and the like are temporarily plugged, and meanwhile, the water filling and draining gate openings must be strictly checked, so that the leakage phenomenon cannot occur; a water source fills water into a water tank at the upstream of the test pipe section from a site construction water taking point; starting timing when the test water head reaches a specified water head, and observing the water seepage amount of the pipeline until the observation is finished; during observation, the water level is measured by using corresponding special equipment within a specified time.

Compared with the prior art, the invention has the beneficial effects that:

1) the invention adopts the customized pipe, the steel belt is arranged in the pipe, and the pipe can be connected in series by welding the steel belt with the deformed steel bar; the pipe explosion caused by water seepage or uneven stress due to local staggered joints during deviation correction is avoided;

2) the construction process aims at the conditions that when the height difference from the top of the pipe jacking machine to the bottom of a river bed is low, the soil pressure cannot meet the requirement, the head is easy to incline upwards in the jacking process, and the self-carrying deviation rectification of equipment cannot be solved; carrying out prepressing construction by adopting a cofferdam soil body prepressing method so as to increase the pressure above the pipeline and ensure that jacking is carried out smoothly;

3) according to the invention, the cutter discs are improved, the number of shell cutters is strengthened by encryption, large-particle-size isolated rock blocks and shale layers in the stratum can be effectively cut up, blockage is prevented, and the adaptability to different geological layers is improved;

4) according to the invention, the fixed hoop and the adjusting hoop are arranged at the front cabin of the machine head, and contact friction is carried out between the cabin wall and the rock stratum wall before the cabin wall, so that the abrasion degree of the cabin wall of the machine head is reduced, and the slurry can be prevented from flowing back.

Drawings

FIG. 1 is a schematic diagram of the overall construction structure of a muddy water balanced push bench of the invention;

FIG. 2 is a schematic structural view of a machine head, a pipeline and the inner part of a working well in the muddy water balanced type pipe jacking machine;

FIG. 3 is a schematic diagram of a mounting structure of a hydraulic station, a deviation-rectifying oil cylinder, a control cabinet and a laser theodolite in the muddy water balance type push bench;

FIG. 4 is a schematic diagram of the internal structure of a middle front bin of the muddy water balance type push bench of the invention;

FIG. 5 is a schematic structural view of a cutter head and a front bin in the muddy water balanced push bench of the invention;

FIG. 6 is a structural schematic view of a cutter head in a muddy water balance type pipe jacking of the invention;

FIG. 7 is a schematic view of a drilling tool apron in the muddy water balanced type push bench of the present invention;

FIG. 8 is a schematic view of a pipeline structure in the muddy water balanced type push bench of the present invention;

FIG. 9 is a schematic structural view of a fixing ring and an adjusting plate in the muddy water balanced push bench of the present invention;

FIG. 10 is a schematic structural view of an adjusting plate in the muddy water balanced push bench of the present invention;

FIG. 11 is a schematic cross-sectional view of a fixing ring in a muddy water balanced push bench of the present invention;

FIG. 12 is a schematic structural view of a baffle II in the muddy water balanced push bench of the present invention;

FIG. 13 is a schematic sectional view of an adjusting plate in the muddy water balanced push bench of the present invention;

in the figure: 1. a machine head; 101. a cutter head; 1011. a cutter groove I; 1012. a cutter groove II; 102. drilling a cutter holder; 1021. drilling and milling a cutter; 1022. a shell knife; 103. adjusting the hoop; 1031. a fixing ring; 10310. mounting grooves; 103101, and a guide groove I; 1032. an adjusting plate; 10321. a resistance plate I; 103211, a guide block I; 103212, guide block II; 103213, fixing blocks; 103214, a guide rod I; 10322. a resistance plate II; 103221, guide block III; 103222, a guide groove II; 103223, a guide rod II; 10323. a guide rod III; 10324. a spring I; 10325. a spring II; 104. a center knife; 105. fixing the hoop; 106. a material introducing port; 107. a front bin; 108. a drive section; 1081. a drive motor; 2. a pipeline; 21. a steel belt; 3. a main jacking mechanism; 4. a slurry stirring mechanism; 41. a stirring pump; 42. a mud pump; 43. a mud conveying pipe; 5. a slurry precipitation mechanism; 51. a sludge discharge pump; 52. a sludge discharge pipe; 6. a hydraulic station; 7. a deviation rectifying oil cylinder; 8. a control cabinet; 9. a laser theodolite; 10. a track; 11. supporting steel sheet piles; 12. deformed steel bar; 13. a geological formation; 14. and (4) working wells.

Detailed Description

For the convenience of understanding of those skilled in the art, the technical scheme of the present invention is further specifically described below with reference to fig. 1 to 13;

a muddy water balance type pipe jacking machine comprises a machine head 1, a main jacking mechanism 3, a hydraulic station 6, a deviation rectifying oil cylinder 7, a control cabinet 8 and a laser theodolite 9; the machine head 1 comprises a cutter head 101, a drilling cutter seat 102, an adjusting hoop 103, a central cutter 104, a fixed hoop 105, a material guiding port 106, a front bin 107 and a driving part 108; the hydraulic station 6, the deviation rectifying oil cylinder 7 and the control cabinet 8 are positioned in a front bin 107 of the machine head 1; the cutter head 101 is fixed at the top end of the front bin 107; the drilling tool holder 102 and the center tool 104 are fixed on the cutter head 101; the fixed hoop 105 and the adjusting hoop 103 are fixed on the outer wall of the front bin 107 and are positioned on one side of the cutter head 101; the driving part 108 is positioned inside the front bin 107 and on one side of the cutter head 101; the material introducing port 106 is located on one side of the driving part 108, and the driving part 108 is provided with a driving motor 1081.

A cutter groove I1011 and a cutter groove II 1012 are arranged on the cutter head 101; the drilling tool holder 102 and the central tool 104 are respectively fixed in the tool groove I1011 and the tool groove II 1012; the drilling tool holder 102 is provided with a plurality of drilling and milling tools 1021 and shell tools 1022, the drilling and milling tools 1021 are positioned at two sides of the drilling tool holder 102, the drilling directions are opposite, and the shell tools 1022 and the drilling and milling tools 1021 are fixed in a staggered manner; in order to improve the adaptability of the cutter head 101 to various stratum environments and improve the drilling efficiency, the number of the shell cutters 1022 is encrypted and strengthened, and large-particle-size isolated rock blocks and shale layers in the stratum can be effectively chopped, so that the pipeline is prevented from being blocked.

The adjustment band 103 comprises a fixing ring 1031 and an adjustment plate 1032; two rows of mounting grooves 10310 are circumferentially arranged on the outer wall of the fixing ring 1031 and are arranged in a staggered manner; the adjusting plate 1032 is fixed in the mounting groove 10310; guide grooves I103101 are formed in two ends of the mounting groove 10310; the adjusting plate 1032 comprises a resistance plate I10321, a resistance plate II 10322, a guide rod III 10323, a spring I10324 and a spring II 10325; the baffle I10321 is internally provided with a cavity, one end of the outer part of the baffle I10321 is provided with a guide block I103211, the other end of the baffle I10321 is provided with a fixed block 103213, a guide rod I103214 is arranged in the cavity, and the outer side surface of the baffle I10321 is provided with a guide block II 103212; the guide rod III 10323 is fixed on the fixed block 103213; the spring I10324 is sleeved with a guide rod III 10323; the inner part of the resistance plate II 10322 is a cavity and is sleeved with the resistance plate I10321, a guide rod II 103223 is fixedly arranged in the resistance plate II 10322, a guide groove II 103222 is formed in the side wall of the resistance plate II 10322 and is matched with the guide block II 103212, the two ends of the spring II 10325 are respectively sleeved with the guide rod II 103223 and the guide rod I103214, and one end of the resistance plate II 10322 is provided with the guide block III 103221; the adjusting plate 1032 is pushed to slide along the guide groove I103101 by the elastic force of the spring I10324, and the guide block III 103221 and the guide block I103211 are arranged in the guide groove I103101 to play a guiding role; when the adjusting plate 1032 is stressed to retract, the spring II 10325 is extruded and contracted by the resistance plate I10321 and the resistance plate II 10322, the guide block II 103212 slides along the guide groove II 103222, and when the adjusting plate 1032 is stressed to reduce the ejection, the resistance plate I10321 and the resistance plate II 10322 are expanded by the elastic force of the spring II 10325 to expand a blocking surface; the fixed hoop 105 is positioned on one side of the adjusting hoop 103; when the pipe jacking machine head 1 performs drilling and tunneling work, the fixed hoop 105 contacts the surface of the geological layer 13 before the outer wall of the front bin, so that the wear rate of the front bin and a sandstone layer can be reduced, and mud can be prevented from flowing back; because the geological formation is complicated changeable so the regulation band 103 can be forced to pop out when meeting soft sand layer and increase the face of stopping to mud, improve and stop sealed effect.

The driving motor 1081 of the driving part 108 provides power to drive the cutter head 101 to rotate for drilling movement; the drilling advancing direction of the machine head 1 is guided and measured through a laser theodolite 9; a plurality of deviation-correcting oil cylinders 7 are circumferentially arranged in the front bin 107, and when deviations occur in different drilling directions, the deviation-correcting oil cylinders 7 in corresponding positions and directions are controlled to be ejected out through the hydraulic station 6 to adjust the drilling directions;

the slurry stirring mechanism 4 comprises a stirring pump 41, a sludge conveying pump 42 and a sludge conveying pipe 43; the sludge feeding pipe 43 is connected to the feed opening 106. The stirring pump 41 stirs the slurry, and then the slurry is pumped by the slurry pump 42 and is fed into the drilling area of the feed port 106 and the cutter head 101 along the slurry pipe 43 to lubricate drilling; the mud sedimentation mechanism 5 comprises a mud pump 51 and a mud pipe 52, the mud pipe 52 is connected with a material guiding port 106, and the crushed material mixed mud generated after drilling is pumped by the mud pump 51 and enters the sedimentation tank for sedimentation treatment through the mud pipe 52.

A track 10, a supporting steel sheet pile 11 and a main jacking mechanism 3 are arranged in the working well 14; the track 10 supports the pipeline 2, and the pipeline 2 is pushed into the culvert through the main jacking mechanism 3; the steel belt 21 is arranged in the pipeline 2 body, the pipeline 2 is welded and connected into a whole by the deformed steel bar 12 through the steel belt 21 in series connection, and water seepage or uneven stress caused by local staggered joints during deviation correction is avoided; if pipe explosion occurs, the front and rear pipelines of the burst pipe section can be welded and connected through the tandem steel belt 21 by adopting a steel plate, so that the continuous jacking construction is ensured.

A construction process of a muddy water balance type pipe jacking machine in a quicksand stratum comprises the steps of early construction preparation; debugging and installing equipment; jacking construction; dismantling equipment; waterproof and antiseptic treatment; a water-closing test; the method comprises the following specific steps:

1. preparation in the early stage of construction:

1) customizing a pipeline, wherein the project adopts a self-improved pipe special for a quicksand/rock abrupt stratum grade III DN 1500; compared with the common pipe jacking pipe, the steel pipe jacking pipe is characterized in that a steel belt is arranged in the middle of the inner side of the pipeline, and the steel belt is connected in series by adopting deformed steel bars and is connected with a pipeline steel reinforcement framework into a whole by welding.

2) Constructing a receiving well and a construction well in a construction site; constructing a support steel sheet pile by adopting an IV-type 9m long dense buckling Larsen steel sheet pile; the Larsen steel sheet pile is driven by a crawler excavator with a vibration hammer; before piling, the steel sheet piles are checked one by one, the steel sheet piles which are rusted and seriously deformed at the locking openings are removed, unqualified steel sheet piles can be used after being trimmed, and grease is coated in the locking openings of the steel sheet piles, so that the steel sheet piles can be conveniently driven and pulled out; measuring and monitoring the inclination of each pile at any time in the inserting and driving process to be not more than 2%, and pulling and re-driving when the inclination is too large and cannot be adjusted by a pulling and aligning method; in construction, the driving sequence is changed according to specific conditions, and one or more driving sequences are adopted to drive the sheet piles to the designed elevation gradually.

3) The original machine head needs to be improved, the number of the machine heads is mainly encrypted by the improved content, and the number of the machine heads comprises 8 shells on the cutter head.

3. And (3) jacking construction:

1) preparing slurry: and stirring and preparing the slurry by a slurry preparation machine and carrying out slurry introduction and discharge along with jacking of a pipe jacking machine.

2) And (4) hole forming: before going out of a hole, all equipment is comprehensively checked, whether operating systems such as hydraulic pressure, electricity, mud jacking, air pressure, water pressure, illumination, communication and ventilation can work normally or not, whether various electric meters, pressure gauges, reversing valves, sensors, flowmeters and the like can correctly display that the equipment enters a working state or not is judged, then linkage debugging is carried out, and after the situation that no fault exists is confirmed, the equipment can be ready to go out of the hole, and if the equipment has a problem, the equipment needs to be adjusted, maintained or replaced in time.

Checking whether the precipitation effect of the outer section of the hole opening meets the requirement or not through the water level observation hole; the annular gap between the water stop ring at the opening and the shell of the machine head is uniform, sealed and free of slurry inflow; after the ground outside the tunnel has no obvious settlement, the sealing door can be removed; firstly, removing a brick wall, and then removing a combined steel seal door outside a well; after the sealing door is removed, on the premise of ensuring personal safety, obstacles such as metal objects or large hard blocks and the like possibly existing outside the opening are immediately removed, and then the machine head is immediately cut into the soil layer, so that the soil body in front is prevented from loosening and collapsing.

3) Jacking: the method comprises the following steps that before a tunneling system is started, sufficient hydraulic oil in a hydraulic pump set is ensured; each joint of the hydraulic oil hose and the slurry pipeline is reliable, and the number of the joints is matched; all control switches on the control console are in neutral positions or stop positions; all cables and electric wires are firmly connected; the power supply meets the specified value; the rotation direction of the motor is correct.

In the initial stage of jacking after the pipeline is out of the hole, the direction of the machine head is mainly controlled by the installation direction of the guide rail, on one hand, the pushing speed of the main jack is reduced, and on the other hand, the deviation correction of the oil cylinder and the deviation correction of the machine head are continuously adjusted; strictly controlling the jacking deviation of a pipeline with the length of 5m, wherein the left deviation, the right deviation and the elevation deviation can not exceed 5 mm; and in the jacking process, the relay ring is timely placed according to the jacking force calculation and the actual jacking force condition so as to reduce the working load of the rear jack and reduce the equipment abrasion.

After one jacking stroke is finished, the jack and the annular sizing block are withdrawn, and then a pipe can be placed in the working well; before the pipe is hung into a working well, the quality of the pipe is checked, after the pipe is qualified, a wedge-shaped rubber ring is arranged at the front end opening of the pipe, silicone oil is smeared on the surface of the rubber ring, and the friction force between joints and the joint is small.

4) Measurement: establishing a ground and underground measurement control system according to a set pipeline central line and a set working pit position, and arranging a control point in a place which is not easy to disturb, clear in sight line and convenient to check, and protecting; setting a temporary level point introduced from a ground level point in the jacking pit, correcting and adjusting the elevation of an instrument during shift switching, introducing a jacking axis into the pit from the center of a designed pipeline through a theodolite, and then performing centering observation; the measuring instrument is erected at the rear part of the pit; the initial jacking working well enters the soil layer, and the measurement is not less than 1 time when the initial jacking working well is jacked for 30 cm; during normal jacking, the measurement is not less than 1 time per 1m of jacking; measuring should be added 30m before entering the receiving working well, and measuring should not be less than 1 time per 30cm of jacking; after each jacking process is finished, the horizontal axis and the elevation of each jacking process must be retested in a full line, a pipeline jacking track diagram is drawn, and construction quality monitoring personnel check and recheck the track diagram.

5) Rectifying deviation: the jacking deviation correction can be carried out by adopting a method of adjusting deviation correcting jacks, if the pipeline deviates to the left, the jacks adopt a left stretching and right retracting method, and vice versa; if the elevation and direction deviation exists, correcting the surface with large deviation; and (5) analyzing the development trend when a large deviation occurs, and performing frequent correction step by step and frequent fine adjustment and correction.

6) Grouting: grouting is carried out by the machine head and the side wall through a grouting pump and a pipeline, a complete annular slurry lubricating sleeve is formed between the outer wall of the pipe and the soil layer, the original dry friction state is changed into a liquid friction state, and jacking resistance can be greatly reduced; the operation rules of pipe jacking grouting must be strictly executed by special persons, and quality personnel check the quality of the pipe jacking grouting strictly.

The slurry is discharged into a slurry processor and a sedimentation tank for processing through the suction of a recovery pump and the pipeline transmission; in the process, the mud jacking at the tail end of the pipe jacking machine head is synchronously mud jacking along with the jacking of the pipeline, and the mud is tracked and supplemented at a proper position of the concrete pipeline so as to supplement the mud loss in the jacking process.

7) Cofferdam soil body pre-compaction: when the height difference from the machine head to the bottom of the river bed is lower or less than 1 m; piling and covering soil above the pipeline along the way by an excavator; the soil body overburden thickness is 1.5m, the width is larger than the diameter of the pipe material of the jacking pipe by 2m, and the two sides are evenly distributed by taking the central axis of the jacking pipe as a reference; a half-width cofferdam construction mode is adopted in the cofferdam soil body compaction process, namely, after construction is completed on the left side of the river channel, soil body prepressing and pipe jacking construction are carried out on the right side of the river channel, and then the left prepressing soil body is removed to guarantee the smoothness of the river channel.

8) Entering a hole: when the pipe jacking machine head enters the hole, a pillow and a roller are pre-arranged in the receiving pit, and when the front part of the pipe jacking machine is close to the outer edge of the receiving pit, a sealing door is removed; the length of the reserved pipe joint is considered after the pipe joint is jacked into the receiving pit, so that pipe disassembly is avoided as much as possible, construction of a connector is facilitated, and the length of the exposed pipe section is less than one third of the length of the pipe.

9) Pipeline concatenation and waterproof: the inner surface of the socket is uniformly coated with a liquid lubricant, then the rubber rings are respectively sleeved on the sockets and coated with the liquid lubricant, and the pipes are welded and connected into a whole by adopting 20mm deformed steel strips in series.

The slurry balance pipe jacking machine head adopts a special machine head, and a pipeline interface in the jacking process adopts water stopping measures: firstly, the rubber ring seal at the connecting position of the steel bell mouth interface prevents underground water from entering the pipeline; secondly, a river-crossing special pipeline is customized, a groove closed connector is reserved at the position of the receiving port, so that underground water is effectively prevented from permeating, thirdly, after the pipe-jacking is completed, the inner side of the connector is treated by asbestos cement, so that the pipe belt can be effectively prevented from cracking, the underground water is prevented from permeating, and three layers of waterproof and anti-permeability measures can effectively prevent the underground water from permeating into the pipeline and have a good water-stopping effect; if there is some water seepage after three-layer water-proofing treatment, the leakage-stopping quick-setting agent without water leakage is used to quickly stop water.

4. Water shut-off experiment: test method

1) Preparation work: before irrigation, cleaning up the inspection well to prevent floating of scum in the inspection well on the water surface after water filling so as to influence the testing precision; temporary plugging is carried out on a reserved hole, an embedded pipe opening, an inlet and an outlet and the like, meanwhile, a water filling gate and a water discharging gate must be strictly checked, a leakage phenomenon cannot occur, a designed water head elevation is calculated after the work is finished, and then the selection of a test water head is determined according to the result of comparing the designed water head with the pipe top inner wall and the well head elevation of an upstream inspection well; then, an irrigation water amount observation scale can be arranged for observing the water seepage amount reached by the water amount during irrigation.

2) And (3) irrigation: a water source fills water into the water tank at the upstream of the test pipe section from a site construction water taking point, but because the pipe diameter of the site water taking point is small, a water spraying tank car is adopted to fill water into the water tank at the upstream of the test pipe section while water is filled from the water taking point; starting timing when the test water head reaches a specified water head, observing the water seepage amount of the pipeline, and if serious seepage occurs until the observation is finished, continuously supplementing water into the test pipe section to keep the water head of the test section constant so as to better find a seepage place and mark the seepage place; the observation time of the seepage amount is not less than half an hour.

3) And (3) water level observation:

a. the water level when irrigating water can be measured by a water level scale;

b. when the water is irrigated to the designed water level for water seepage measurement, a water level measuring needle is adopted to measure the water level; the reading precision of the water level measuring needle is 1/10 mm;

c. the interval time from the water irrigation to the designed water depth to the beginning of the water seepage determination is 26 hours;

d. the interval time between the initial reading and the unread number of the measured water level is 24 h.

The foregoing is merely exemplary and illustrative of the present invention and various modifications, additions and substitutions may be made by those skilled in the art to the specific embodiments described without departing from the scope of the present invention as defined in the accompanying claims.

Claims

1. A muddy water balance type pipe jacking machine comprises a machine head, a main jacking mechanism, a hydraulic station, a deviation rectifying oil cylinder, a control cabinet and a laser theodolite; the machine head comprises a cutter head, a drilling cutter holder, an adjusting hoop, a center cutter, a fixed hoop, a material guiding hole, a front bin and a driving part; the hydraulic station, the deviation-correcting oil cylinder and the control cabinet are positioned in a front cabin of the machine head; the cutter head is fixed at the top end of the front bin; the drilling tool apron and the central tool are fixed on the cutter head; the fixed hoop and the adjusting hoop are fixed on the outer wall of the front bin and are positioned on one side of the cutter head; the driving part is positioned in the front bin and on one side of the cutter head; the material guiding port is positioned on one side of the driving part, and the driving part is provided with a driving motor;

the adjusting hoop comprises a fixing ring and an adjusting plate; two rows of mounting grooves are circumferentially arranged on the outer wall of the fixing ring and are arranged in a staggered manner; the adjusting plate is fixed in the mounting groove; guide grooves I are formed in two ends of the mounting groove; the adjusting plate comprises a blocking plate I, a blocking plate II, a guide rod III, a spring I and a spring II; the baffle plate I is internally provided with a cavity, one end of the outer part of the baffle plate I is provided with a guide block I, the other end of the baffle plate I is provided with a fixed block, a guide rod I is arranged in the cavity, and the outer side surface of the baffle plate I is provided with a guide block II; the guide rod III is fixed on the fixed block; the spring I is sleeved with a guide rod III; the inner part of the baffle plate II is a cavity and is sleeved with the baffle plate I, a guide rod II is fixedly arranged in the baffle plate II, a guide groove II matched with a guide block II is formed in the side wall of the baffle plate II, two ends of the spring II are respectively sleeved with the guide rod II and the guide rod I, and one end of the baffle plate II is provided with a guide block III; the adjusting plate is pushed to slide along the guide groove I through the elasticity of the spring I, and the guide block III and the guide block I are arranged in the guide groove I; when the adjusting plate is stressed and retracted, the spring II is extruded and contracted by the blocking plate I and the blocking plate II, and the guide block II slides along the guide groove II; the fixed hoop is positioned on one side of the adjusting hoop;

the cutter head is provided with a cutter groove I and a cutter groove II; the drilling tool apron and the central tool are respectively fixed in the tool groove I and the tool groove II; the drilling and milling cutter seat is provided with a plurality of drilling and milling cutters and shell cutters, the drilling and milling cutters are positioned on two sides of the drilling and milling cutter seat and have opposite drilling directions, and the shell cutters and the drilling and milling cutters are fixed in a staggered manner;

the driving motor of the driving part provides power to drive the cutter head to rotate for drilling movement; guiding and measuring the drilling advancing direction of the machine head through a laser theodolite; a plurality of deviation-correcting oil cylinders are circumferentially arranged in the front bin, and the deviation-correcting oil cylinders in corresponding positions and directions are controlled to eject out to adjust the drilling direction through a hydraulic station when the deviation occurs in different drilling directions; the slurry stirring mechanism comprises a stirring pump, a sludge conveying pump and a sludge conveying pipe; the mud feeding pipe is connected with a feed inlet; the mud sedimentation mechanism comprises a mud pump and a mud pipe, and the mud pipe is connected with the feed inlet; a track, a supporting steel sheet pile and a main jacking mechanism are arranged in the working well; the track supports the pipeline, and the pipeline top is pushed into the culvert through the main top mechanism; the pipeline is internally provided with a steel belt, and the pipeline is connected with the deformed steel bar into a whole by welding through the steel belt in series connection.

2. A construction process of a muddy water balance type pipe jacking machine in a quicksand stratum comprises the steps of early construction preparation; debugging and installing equipment; jacking construction; dismantling equipment; a water-closing test; the method is characterized by comprising the following specific steps:

1) preparation in the early stage of construction: comprises the steps of customizing a pipeline; building a receiving well and a construction well; the machine head is improved; wherein the pipeline adopts an autonomously improved customized pipe; constructing reinforced concrete back walls at the bottoms of the receiving well and the construction well, and constructing support steel sheet piles at the middle upper part; additionally, the number of the shell knives is encrypted and strengthened;

2) equipment debugging and installation: the laser theodolite, the track, the main jacking equipment and the machine head are fixedly arranged; a guardrail enclosure is additionally arranged on a construction site, an upper escalator and a lower escalator are arranged in a construction well, and a mud preparation pool, a material equipment and pipe storage warehouse, a construction temporary access way and a construction rest area are arranged on the periphery of the construction well; sequentially installing various devices and systems; the system comprises a main jacking system, a grouting and discharging system and a power supply arrangement, wherein after all equipment systems are installed, test run debugging and safety inspection before hole exit are carried out until jacking operation is carried out after the equipment systems are qualified;

3) and (3) jacking construction: after all the equipment is completely checked, firstly, a first section of pipe is hung, a water outlet pipe, a mud pipe and other various water circuit lines are connected, after the first section of pipe is jacked in until the first section of pipe is finished, the jack is retracted, various pipelines and water and power circuits are disassembled, then, a section of pipe is hung down, various water pipes, mud pipes and other water and power circuits are reconnected, jacking is continued, and circulation is performed according to examples; grouting the head and the side wall through a grouting pump and a pipeline in the jacking process, forming a complete annular slurry lubricating sleeve between the outer wall of the pipe and a soil layer, changing the original dry friction state into a liquid friction state, synchronously grouting the head end and the tail end of the pipe jacking machine along with the jacking of the pipeline in the process, and tracking and supplementing the slurry at a proper position of a concrete pipeline; measuring and correcting deviation according to design requirements in the jacking process; when the construction section passes through a river channel, the pressure of the soil body reaches the requirement of a jacking pipe by adopting a cofferdam soil body prepressing mode; internal thread steel in the range of 18mm-25mm is welded and connected with the pipe in series while the pipe is pushed; after the pipe jacking is finished, sequentially disassembling each construction device according to the construction rules and then transporting out of the construction site;

4) water-closing test: cleaning up the inspection well before irrigation; for the reserved holes, the pre-buried pipe orifices and the inlet and outlet are temporarily plugged, and meanwhile, the water filling and draining gate orifices must be strictly checked, so that the leakage phenomenon cannot occur; a water source fills water into a water tank at the upstream of the test pipe section from a site construction water taking point; starting timing when the test water head reaches a specified water head, and observing the water seepage amount of the pipeline until the observation is finished; during observation, the water level is measured by using corresponding special equipment within a specified time.

3. The construction process of the muddy water balanced type pipe push bench in the quicksand stratum as claimed in claim 2, characterized in that in the pipe jacking process in step 3), a ground and underground measurement control system is established according to the set pipeline central line and the working pit position; setting a temporary level point introduced from a ground level point in the jacking pit, correcting and adjusting the elevation of an instrument during shift switching, introducing a jacking axis into the pit from the center of a designed pipeline through a theodolite, and then performing centering observation; the initial jacking working well enters the soil layer, and the measurement is not less than 1 time when the initial jacking working well is jacked for 30 cm; during normal jacking, the measurement is not less than 1 time per 1m of jacking; and the measurement should be increased 30m before entering the receiving working well, and the measurement should not be less than 1 time for every 30cm of jacking.

4. The process of claim 2, wherein the slurry composition of step 3) comprises bentonite, alkaline minerals, polyacrylamide and water; wherein, the mass ratio of bentonite: basic inorganic substances: polyacrylamide: water (300-; the alkaline inorganic substance is sodium carbonate or sodium hydroxide or a compound of the sodium carbonate and the sodium hydroxide; the mud stirring time is 150-200s, the stirring speed is 280-320r/min, and the grouting pressure is 0.2-0.4 MPa.

5. The construction process of the muddy water balanced type pipe push bench in the quicksand stratum as claimed in claim 4, characterized in that bentonite: basic inorganic substances: polyacrylamide: 380kg of water, 6kg of water, 1.3kg of water and 810kg of water; the stirring time of the slurry is 180s, the stirring speed is 300r/min, and the grouting pressure is 0.35 MPa.

6. The construction process of the muddy water balanced push bench in the quicksand stratum as claimed in claim 2, characterized in that in step 3), the cofferdam soil body prepressing process: when the height difference from the machine head to the bottom of the river bed is lower or less than 1 m; piling and covering soil above the pipeline along the way by an excavator; the soil body overburden thickness is 1.5-2m, the width is 1.5-2m larger than the diameter of the pipe material of the jacking pipe, and two sides are evenly distributed by taking the central axis of the jacking pipe as a reference; the method of half cofferdam construction is adopted in the cofferdam soil body compaction process, namely, after construction is completed on the left side of the river channel, soil body prepressing and pipe jacking construction are carried out on the right side, and then the left side prepressing soil body is removed.

7. The construction process of the muddy water balanced type pipe push bench in the quicksand stratum as claimed in claim 2, characterized in that the hole entering process in step 3): when the pipe jacking machine head enters the hole, a pillow and a roller are pre-arranged in the receiving pit, and when the front part of the pipe jacking machine is close to the outer edge of the receiving pit, a sealing door is removed; the length of the reserved pipe joint is considered after the pipe joint is jacked into the receiving pit, so that pipe disassembly is avoided as much as possible, construction of a connector is facilitated, and the length of the exposed pipe section is less than one third of the length of the pipe.

8. The construction process of the muddy water balanced type pipe push bench in the quicksand stratum as claimed in claim 2, characterized in that step 3) pipeline concatenation and waterproof measures are adopted: uniformly coating a liquid lubricant on the inner surface of the socket, then respectively sleeving the rubber rings on the sockets, coating the liquid lubricant, and welding the pipes into a whole by adopting internal thread steel in a range of 18-25mm through a series connection steel belt; and (3) taking water stopping measures at a pipeline interface in the jacking process: firstly, sealing a rubber ring at the connecting position of a steel socket port interface; secondly, a river-crossing special pipeline is customized, and a groove sealing interface is reserved at the position of the socket; thirdly, after the pipe jacking is finished, the inner side of the interface is processed by adopting asbestos cement to prepare an interface pipe belt; if there is some water seepage after three-layer water-proofing treatment, the leakage-stopping quick-setting agent without water leakage is used to quickly stop water.

9. The process of claim 8, wherein the screw steel is 20 mm.

10. The construction process of the muddy water balanced type pipe pushing jack in the quicksand stratum as claimed in claim 2, characterized in that the customized pipe in step 1) is a special grade III DN1500 pipe for quicksand/rock abrupt stratum, and a steel belt is arranged inside the pipe.