Automatic drainage and improved muck recycling system and working method for preventing blowouts in tunnel boring machine screw conveyors

Abstract

This invention discloses an automatic drainage and modified soil recycling system and its working method for preventing blowouts in shield tunneling screw conveyors, belonging to the field of shield tunneling technology. The automatic drainage and modified soil recycling system for preventing blowouts in shield tunneling screw conveyors includes a screw conveyor, a high-pressure automatic drainage system, and a modified soil recycling system. The high-pressure automatic drainage system includes four water pressure relief valves evenly spaced along the axial direction of the screw conveyor on its upper side. These valves are connected to drainage pipelines and are uniformly regulated by a drainage integrated system. The modified soil recycling system includes a transfer box, a transverse conveying device, a return conveying device, and a soil conditioner injection system. Through the coordinated operation of the high-pressure automatic drainage system and the modified soil recycling system, real-time intelligent control of the water pressure within the screw conveyor and efficient recycling of the modified soil are achieved, effectively reducing the risk of blowouts, improving the soil conditioner effect, and reducing the use of chemical agents.

Description

Technical Field

[0001] This invention relates to an automatic drainage and improved slag recycling system and working method for preventing blowouts in a shield tunneling screw conveyor, belonging to the field of shield tunneling technology. Background Technology

[0002] In urban rail transit, water conservancy and hydropower infrastructure construction, tunnel boring machine (TBM) technology is widely used due to its high efficiency and safety. However, when earth pressure balance TBMs are excavating in water-rich sandy strata, the abundant groundwater, high water pressure, and high permeability of the excavated soil often lead to blowouts in the screw conveyor. During a blowout, high-pressure water forms a concentrated seepage flow in the coarse-grained soil, carrying excavated soil and ejecting it from the discharge port. This not only affects the efficiency of excavation but can also cause fluctuations in the soil chamber pressure, leading to instability at the excavation face, seriously threatening construction safety and increasing project costs.

[0003] Currently, the main engineering approach to address the blowout problem in screw conveyors is soil amendment technology, which involves adding foaming agents, polymers, and other amendments to improve the fluidity and water-stopping properties of the soil. However, single amendments have limited effectiveness under high water pressure conditions, and the extensive use of chemical agents poses environmental hazards. For example, the concentration of chemical agents in shield tunnel soil can reach over 5000 mg / kg, and direct dumping of untreated soil can have long-term impacts on the ecological environment and human health. Furthermore, existing mechanical modification methods for screw conveyors are outdated, lacking real-time automatic control of water pressure within the soil chamber and screw conveyor, and hindering the efficient recycling of amended soil.

[0004] As tunnel boring machine (TBM) construction faces increasingly complex geological challenges, such as mud cake formation in cohesive soils and cutter wear in hard rock formations, the shortcomings of traditional technologies in waste soil treatment are becoming increasingly apparent. Existing waste soil separation technologies and recycling processes are not systematic, and the processing equipment suffers from low levels of intelligence and poor adaptability to different geological formations, leading to insufficient mud circulation and resource waste. Particularly in water-rich sandy strata, effectively reducing the water pressure inside the screw conveyor, improving the physical properties of the waste soil, and achieving recycling have become urgent technical challenges that need to be addressed. Summary of the Invention

[0005] The purpose of this invention is to provide an automatic drainage and improved slag circulation system for preventing blowouts in a tunnel boring machine (TBM) screw conveyor, in order to solve the above-mentioned problems, achieve automatic control of water pressure inside the screw conveyor and improve the efficient circulation of slag, thereby enhancing the safety and environmental friendliness of TBM construction.

[0006] This invention is achieved through the following technical solution: an automatic drainage and improved slag recycling system for preventing blowouts in a tunnel boring machine screw conveyor, characterized in that it comprises:

[0007] The screw conveyor pumps the slag from the soil chamber of the tunnel boring machine and transports it to the outside. The screw conveyor includes a cylinder, in which a screw rotor is rotatably installed. A slag outlet is provided on the lower rear side of the cylinder, and a flow meter and a water pressure gauge are provided on the lower side of the slag outlet.

[0008] The high-pressure automatic drainage system includes four water pressure relief valves evenly spaced along the axial direction of the screw conveyor on the upper side of its cylinder. The water pressure relief valves are connected to the drainage pipeline and are uniformly regulated by the drainage integrated system.

[0009] An improved slag recycling system includes a conversion box, a transverse conveying device, a return conveying device, and an amendment injection system. The conversion box has an upper gate at its upper end and a lower gate at its lower end. The upper gate of the conversion box is fixedly connected to the slag outlet of a screw conveyor. The transverse conveying device is located outside the conversion box. The feed end of the transverse conveying device is connected to a return port located on the lower side wall of the conversion box. The feed end of the return conveying device is connected to the discharge end of the transverse conveying device. The discharge end of the return conveying device is connected to the tunnel boring machine's soil chamber. The feed end of the return conveying device is connected to the amendment injection system. A separation baffle is located inside the conversion box corresponding to the return port. The separation baffle is hinged to the lower side wall of the conversion box. A drive mechanism for opening and closing the separation baffle is located outside the conversion box.

[0010] In this invention, the screw conveyor transports excavated soil through the rotation of its screw rotor. Its discharge port is connected to the improved excavated soil recycling system, providing basic transportation conditions for excavated soil improvement and recycling. The main function of the high-pressure automatic drainage system is to monitor the water pressure inside the screw conveyor in real time through the water pressure relief valve, automatically drain water when the water pressure exceeds the standard, and work with the drainage integration system to achieve dynamic control of the water pressure inside the screw conveyor, avoiding high water pressure causing gushing. The main function of the improved excavated soil recycling system is to regulate the flow rate of excavated soil through the separation baffle of the conversion box, and send the returned excavated soil back to the shield machine soil chamber through the transverse conveying device and the longitudinal conveying device. When the excavated soil is returned, the improver is injected into the returned excavated soil through the improver injection system, realizing efficient improvement and recycling of excavated soil, reducing the amount of improver used at one time and environmental pollution.

[0011] Furthermore, the water pressure relief valve is a solid-liquid separation type automatic pressure relief valve, which opens to drain water and control water pressure when the water pressure reaches the set value.

[0012] Furthermore, both the transverse conveying device and the return conveying device are screw conveying devices, and their driving devices are both geared motors.

[0013] Furthermore, for ease of control, both the upper gate and the lower gate are gates with adjustable opening.

[0014] Furthermore, to ensure the effectiveness of the modifier injection, the upper side wall of the return conveying device is connected to the modifier injection system via a one-way valve.

[0015] Furthermore, a circulating slag discharge gate is installed at the connection between the return conveying device and the tunnel boring machine's soil chamber.

[0016] Furthermore, the driving mechanism for opening and closing the separation partition includes a hydraulic cylinder and a connecting rod. The connecting rod is fixedly connected to the hinge shaft of the separation partition on the outside of the conversion box, and the hydraulic cylinder is hinged to the side wall of the conversion box and hinged to the connecting rod.

[0017] This invention also provides a working method for the above-mentioned automatic drainage and improved slag circulation system for preventing blowouts in a tunnel boring machine screw conveyor. The system is characterized by real-time monitoring of water pressure at corresponding locations within the screw conveyor via various water pressure relief valves, and automatic drainage when water pressure exceeds the standard. The integrated drainage system acquires real-time water pressure at various locations within the screw conveyor and automatically regulates drainage. It also adjusts the upper gate, lower gate, separation baffle, and circulating slag discharge gate based on the water pressure and flow rate within the screw conveyor, thereby achieving dynamic control of water pressure within the screw conveyor and preventing blowouts caused by high water pressure. The slag flow rate is adjusted via the separation baffle of the conversion box, and the slag is transported back to the tunnel boring machine's soil chamber via a transverse conveying device and a return conveying device. During slag return, an amendment is injected into the returned slag through an amendment injection system, and the returned slag enters the tunnel boring machine's soil chamber to improve the soil within the chamber.

[0018] Furthermore, the operation method of the high-pressure automatic drainage system is as follows: the drainage integration system acquires the water pressure and flow rate at each point in real time, and the water pressure relief valve is set to an automatic drainage pressure of 10 kPa; when the flow rate at the slag outlet of the screw conveyor is less than 1 cm³, the system will automatically drain the water. 3 When the flow rate is less than 10 kPa or the water pressure is less than 10 kPa, all water pressure relief valves are closed; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3 When the water pressure is less than 10 kPa, open the first and second water pressure relief valves near the soil chamber; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3 When the water pressure is greater than 10 kPa but less than 20 kPa, a slight jetting occurs in the tunnel boring machine. All water pressure relief valves are opened, and the upper gate opening is controlled to 70% via the integrated drainage system. When the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3 When the water pressure is greater than 20 kPa, the shield tunneling machine experiences severe gushing. At this time, all water pressure relief valves are opened, the lower gate is closed through the drainage integrated system, the separation baffle and the circulating slag discharge gate are fully opened, the improved slag circulation system is put into operation, the pressure balance in the shield tunneling machine is stabilized, and the ratio of the improver injection is automatically adjusted according to the water pressure and water flow to improve the slag.

[0019] The beneficial effects of this invention are as follows: By working in concert with the high-pressure automatic drainage system and the improved slag recycling system, this invention achieves real-time intelligent control of the water pressure inside the screw conveyor and efficient recycling of the improved slag, which can effectively reduce the risk of gushing, improve the effect of slag improvement, reduce the use of chemical agents and slag discharge, and more effectively prevent gushing disasters in shield tunneling construction, fundamentally prevent gushing disasters, and improve the safety and environmental protection of shield tunneling construction. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the automatic drainage and improved slag recycling system for preventing blowouts in the shield tunnel screw conveyor in this invention;

[0021] Figure 2 This is a schematic diagram of the improved slag and soil recycling system in this invention;

[0022] In the diagram, 1. Tunnel boring machine soil chamber; 2. Circulating slag discharge gate; 3. Water pressure relief valve; 4. Drainage pipeline; 5. Spiral rotor; 6. Cylinder; 7. Spiral conveyor drive unit; 8. Drainage integrated system; 9. Upper gate; 10. Slag outlet; 11. Modifier injection system; 12. Transfer box; 13. Lower gate; 14. Lateral conveying drive unit; 15. Lateral conveying device; 16. Return conveying drive unit; 17. Check valve; 18. Separation baffle; 19. Flow meter and water pressure gauge; 20. Return conveying device; 21. Return outlet; 22. Hydraulic cylinder; 23. Connecting rod. Detailed Implementation

[0023] The invention will be further described below through non-limiting embodiments and in conjunction with the accompanying drawings:

[0024] As shown in the attached figure, an automatic drainage and improved spoil circulation system for preventing blowouts in a tunnel boring machine (TBM) screw conveyor includes a screw conveyor, a high-pressure automatic drainage system, and an improved spoil circulation system, wherein:

[0025] A screw conveyor is used to pump slag from the soil chamber 1 of a tunnel boring machine and transport it to the outside. The screw conveyor includes a cylinder 6, in which a screw rotor 5 is rotatably installed. A screw conveyor drive device 7 is installed at the rear of the cylinder 6, which drives the screw rotor 5 to rotate. A slag outlet 10 is installed on the lower rear side of the cylinder 6. A flow meter and a water pressure gauge 19 are installed on the cylinder 6 below the slag outlet 10 to monitor the flow rate and water pressure near the slag outlet 10. The monitored flow rate and water pressure signals are fed back to the drainage integrated system 8 of the high water pressure automatic drainage system. The flow meter can be an ultrasonic flow meter.

[0026] The high-pressure automatic drainage system includes four water pressure relief valves 3 evenly spaced along the axial direction of the screw conveyor on the upper side of its cylinder 6. The first water pressure relief valve is located near the soil chamber 1 of the tunnel boring machine, and the others are arranged in sequence as the second, third, and fourth water pressure relief valves. The water pressure relief valves 3 are connected to the drainage pipeline 4. The water pressure relief valves 3 are preferably solid-liquid separation type automatic pressure relief valves. When the water pressure reaches the set value, they open to control the drainage water pressure. Each water pressure relief valve 3 is uniformly regulated by the drainage integration system 8. The opening and closing of each water pressure relief valve 3 can be controlled through the drainage integration system 8.

[0027] An improved slag recycling system includes a conversion box 12, a transverse conveying device 15, a return conveying device 20, and an amendment injection system 11. The conversion box 12 has a box-shaped structure, with an upper gate 9 at its upper end and a lower gate 13 at its lower end. The upper gate 9 of the conversion box 12 is fixedly connected to the slag outlet 10 of the screw conveyor, and the interface is sealed with rubber gaskets and screws to prevent mud and water leakage. Both the upper gate 9 and the lower gate 13 are adjustable gates, and their operation is driven by a drive device, which can be an electromagnetic push rod or a hydraulic cylinder. The drive device is controlled by the drainage integration system 8 of the high-pressure automatic drainage system, and the opening and closing degree of the upper gate 9 and the lower gate 13 can be controlled according to the high-pressure automatic drainage system. The transverse conveying device 15 is located outside the conversion box 12. The transverse conveying device 15 is a screw conveying device. The screw rotor of the transverse conveying device 15 is driven to rotate by the transverse conveying drive device 14, which is a geared motor. The feed end of the transverse conveying device 15 is connected to the return port 21 provided on the lower side wall of the conversion box 12. A separation partition 18 is provided inside the conversion box 12 corresponding to the return port 21. The separation partition 18 is hinged to the lower side wall of the conversion box 12 through a hinge shaft 21. A drive mechanism for opening and closing the separation partition 18 is provided on the outside of the conversion box 12. When the separation partition 18 is opened or closed, the return port 21 can be opened or closed. In this embodiment, the driving mechanism for opening and closing the separation partition 18 includes a hydraulic cylinder 22 and a connecting rod 23. One end of the hinge shaft 21 extends out of the outside of the conversion box 12. The connecting rod 23 is fixedly connected to the end of the hinge shaft 21 extending out of the conversion box 12 on the outside of the conversion box 12. The hydraulic cylinder 22 is hinged to the side wall of the conversion box 12, and its piston rod is connected to the connecting rod 23. When the piston rod of the hydraulic cylinder 22 extends or retracts, it can drive the separation partition 18 to open and close through the connecting rod 23 and the hinge shaft 21. The hydraulic cylinder 22 is supplied with oil by a hydraulic station, and the oil circuit is controlled by a solenoid valve. The high-pressure automatic drainage system can control the opening of the separation baffle 18 through the solenoid valve. The return conveying device 20 is a screw conveyor, driven by a return conveying drive device 16, which is also a geared motor. The feed end of the return conveying device 20 is connected to the discharge end of the transverse conveying device 15, and the discharge end of the return conveying device 20 is connected to the tunnel boring machine's soil chamber 1. The feed end of the return conveying device 20 is also connected to the improver injection system 11. A pipeline connected to the improver injection system 11 is provided on the upper side wall of the return conveying device 20 cylinder. To prevent high pressure inside the return conveying device 20 from affecting the injection of the improver, a one-way valve 17 is provided on the pipeline.When the improved slag recycling system is in operation, the slag discharged by the screw conveyor can be transported to the return conveyor 20 via the transverse conveyor 15, and then the slag is returned to the tunnel boring machine's soil chamber 1 via the return conveyor 20. During the slag return, an amendment is injected into the returned slag through the amendment injection system 11 to improve the soil properties within the tunnel boring machine's soil chamber 1. In this embodiment, a circulating slag discharge gate 2 is provided at the connection between the return conveyor 20 and the tunnel boring machine's soil chamber 1. The circulating slag discharge gate 2 is closed when the improved slag recycling system is not in operation, and the screw conveyor operates normally to discharge slag. When the improved slag recycling system is in operation, the circulating slag discharge gate 2 is opened, allowing the improved slag to circulate into the tunnel boring machine's soil chamber 1, improving the soil properties within the soil chamber. The opening and closing control of the circulating slag discharge gate 2 is controlled by the drainage integrated system 8.

[0028] The automatic drainage and improved slag circulation system for preventing blowouts in shield tunnel screw conveyors of the present invention integrates a high-pressure automatic drainage system and an improved slag circulation system to achieve real-time control of water pressure inside the screw conveyor and efficient circulation of improved slag, thereby fundamentally preventing blowout disasters and improving the safety and environmental protection of shield tunneling construction.

[0029] The working method of the automatic drainage and improved slag circulation system for preventing blowouts in the shield tunnel screw conveyor is as follows: the water pressure at the corresponding position in the screw conveyor is monitored in real time by each water pressure relief valve 3, and automatic drainage is performed when the water pressure exceeds the standard; the water pressure at each position in the screw conveyor is obtained in real time by the drainage integration system 8 and the drainage is automatically regulated, and the upper gate 9, lower gate 13, separation baffle 18 and circulation slag discharge gate 2 are regulated according to the water pressure and water flow in the screw conveyor, so as to realize the dynamic regulation of the water pressure in the screw conveyor and avoid blowouts caused by high water pressure; the slag flow is regulated by the separation baffle 18 of the conversion box, and the slag is transported back to the shield machine soil chamber 1 through the transverse conveying device 15 and the return conveying device 20, and the improver is injected into the returned slag through the improver injection system 11 during the slag return, and the returned slag enters the shield machine soil chamber 1 to improve the soil properties in the soil chamber.

[0030] The operation method of the high-pressure automatic drainage system is as follows: the drainage integration system 8 acquires the water pressure and flow rate at each point in real time, and the water pressure relief valve 3 is set to an automatic drainage water pressure of 10 kPa; when the flow rate at the slag outlet of the screw conveyor is less than 1 cm³, the system will automatically drain the water. 3 When the flow rate is less than 10 kPa or the water pressure is less than 10 kPa, all water pressure relief valves are closed; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3 When the water pressure is less than 10 kPa and the water flow rate is relatively large, open the first and second water pressure relief valves near the soil chamber; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3When the water pressure is greater than 10 kPa but less than 20 kPa, a slight jetting occurs in the tunnel boring machine. All water pressure relief valves are opened, and the upper gate is opened to 70% via the integrated drainage system. When the flow rate at the slag outlet of the screw conveyor is greater than 1 cm³ / s... 3 When the water pressure is greater than 20 kPa, the shield tunnel experiences severe gushing. All water pressure relief valves are opened, and the lower gate 13 is closed through the drainage integrated system. The separation baffle 18 and the circulating slag discharge gate 2 are fully opened to enable the improved slag circulation system to work, stabilize the pressure balance in the shield tunnel, and automatically adjust the ratio of the improver injection according to the water pressure and water flow to improve the slag.

[0031] The other parts in this embodiment are all existing technologies and will not be described in detail here.

Claims

1. A working method of an automatic drainage and improved spoil recycling system for preventing gushing of a shield screw conveyor, characterized in that, The application relates to a spiral conveyor, a high-water-pressure automatic drainage system and a modified sludge circulating system. The spiral conveyor comprises a barrel (6), a spiral rotor (5) arranged in the barrel (6) and rotating, a sludge outlet (10) arranged at the lower side of the rear part of the barrel (6), and a flowmeter and a water pressure gauge arranged at the lower side of the sludge outlet. The high-water-pressure automatic drainage system comprises four water pressure relief valves (3) arranged on the upper side of the barrel of the spiral conveyor in an axial direction and uniformly spaced, the water pressure relief valves (3) are communicated with a drainage pipeline (4), and the water pressure relief valves (3) are uniformly controlled by a drainage integrated system (8). The modified sludge circulating system comprises a conversion box (12), a transverse conveying device (15), a return conveying device (20) and a modifier injection system (11), the upper end of the conversion box (12) is provided with an upper gate (9), the lower end of the conversion box (12) is provided with a lower gate (13), the upper gate (9) of the conversion box (12) is fixedly connected with the sludge outlet (10) of the spiral conveyor, the transverse conveying device (15) is arranged outside the conversion box (12), the feeding end of the transverse conveying device (15) is connected with the return port arranged at the lower part of the side wall of the conversion box (12), the feeding end of the return conveying device (20) is connected with the discharging end of the transverse conveying device (15), the discharging end of the return conveying device (20) is connected with the earth chamber of the shield machine, the feeding end of the return conveying device (20) is connected with the modifier injection system (11), the inside of the conversion box (12) is provided with a separation partition plate (18) corresponding to the return port, the separation partition plate (18) is hingedly connected with the lower side wall of the conversion box (12), and a driving mechanism for driving the opening and closing of the separation partition plate (18) is arranged outside the conversion box (12). The water pressure of the corresponding position in the spiral conveyor is monitored in real time through the water pressure relief valves, and the automatic drainage is carried out when the water pressure exceeds the standard; the drainage integrated system (8) obtains the water pressure of each position in the spiral conveyor in real time and automatically controls the drainage, and controls the upper gate (9), the lower gate (13), the separation partition plate (18) and the circulating sludge discharge gate (2) according to the water pressure and water flow in the spiral conveyor, so that the dynamic control of the water pressure in the spiral conveyor is realized, and the gushing caused by high water pressure is avoided; the sludge flow is adjusted through the separation partition plate of the conversion box, the sludge is conveyed back to the earth chamber of the shield machine through the transverse conveying device (15) and the return conveying device (20), and the modifier is injected into the return sludge through the modifier injection system (11) when the sludge is returned, so that the return sludge enters the improved earth chamber to improve the soil in the earth chamber of the shield machine. The operation method of the high water pressure automatic drainage system is: the drainage integrated system obtains the water pressure and flow rate of each point in real time, the water pressure relief valve is set to 10 kPa as the automatic drainage water pressure; when the flow rate at the slag outlet of the screw conveyor is less than 1 cm 3 / s or the water pressure is less than 10 kPa, all the water pressure relief valves are in the closed state; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm 3 / s and the water pressure is less than 10 kPa, the first and second water pressure relief valves close to the soil bin are opened; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm 3 / s and the water pressure is greater than 10 kPa but less than 20 kPa, at this time, the shield occurs slight gushing, all the water pressure relief valves are opened, and the opening degree of the upper gate (9) is controlled to 70% through the drainage integrated system; when the flow rate at the slag outlet of the screw conveyor is greater than 1 cm 3 / s and the water pressure is greater than 20 kPa, at this time, the shield occurs serious gushing, all the water pressure relief valves are opened, the lower gate (13) is closed through the drainage integrated system, the separation baffle (18) and the circulating slag discharge gate (2) are completely opened, the improved slag soil circulating system works, the pressure balance in the shield is stabilized, and the improved agent injection ratio is automatically adjusted according to the water pressure and flow rate to improve the slag soil.

2. The method of claim 1, wherein the method further comprises: The water pressure relief valve (3) is a solid-liquid separation type automatic pressure relief valve, which opens the drainage to control the water pressure when the water pressure reaches the set value.

3. The method according to claim 1 or 2, wherein, The transverse conveying device (15) and the return conveying device (20) are both spiral conveying devices, and the driving devices of the transverse conveying device (15) and the return conveying device (20) are both speed reduction motors.

4. The method of claim 3, wherein the shield jacking conveyor jetting prevention, automatic drainage and improved spoil recycling system is characterized by, The upper gate (9) and the lower gate (13) are both gates with adjustable opening degrees.

5. The method of claim 4, wherein the shield jacking conveyor jetting prevention, automatic drainage and improved spoil recycling system is characterized by, The upper side wall of the barrel of the return conveying device (20) is connected with the modifier injection system (11) through a one-way valve.

6. The method of claim 5, wherein the shield jacking conveyor jetting prevention, automatic drainage and improved spoil recycling system is characterized by, The recycling conveying device (20) is provided with a circulating deslagging gate (2) at the connection with the earth chamber of the shield machine.

7. The method according to claim 6, wherein the shield jacking conveyor jetting prevention, automatic drainage and improved spoil recycling system is characterized in that, The drive mechanism for driving the opening and closing of the separation partition (18) comprises a hydraulic oil cylinder and a connecting rod, the connecting rod is fixedly connected with the hinge shaft of the separation partition outside the conversion box, and the hydraulic oil cylinder is hingedly connected to the side wall of the conversion box and hingedly connected with the connecting rod.

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