Breaking-out system and method for shield tunneling through upper-soft and lower-hard stratum

Abstract

The invention relates to the technical field of shield escape, in particular to an escape system and method for a shield to penetrate through an upper-soft-lower-hard stratum, the system comprises a shield tunneling machine and a detection hole, a cutter head is arranged at the top end of the shield tunneling machine, a soil bin and a middle shield are distributed in the shield tunneling machine, a screw conveyor is arranged in the shield tunneling machine, and the middle shield is arranged in the screw conveyor. A grouting tank is arranged in the portion, away from the cutter head, of the shield tunneling machine, a surface passageway of the grouting tank is connected with a conveying pipe, and the conveying pipe is connected with the soil bin and an advanced grouting hole passageway in the top of the shield tunneling machine. The replacement filler and the lubricating material can reduce the friction force between the pebble soil and the cutter head, after the particle size of the muck is further reduced, the damage to mechanical equipment caused by forced escape can be further avoided, and higher safety is achieved; the problems that an existing cutterhead escaping method is low in escaping efficiency, poor in safety and high in construction cost can be effectively solved when the cutterhead escaping method encounters some bedrock stratums which are soft in the upper portion and hard in the lower portion and water-rich sandy gravel stratums.

Description

Technical Field

[0001] The invention relates to the technical field of shield machine escape, and in particular to a shield machine escape system and method for passing through upper soft and lower hard strata. Background Art

[0002] Due to the complexity of geological conditions during shield construction and the shield machine's own failures and improper operation that are often encountered during construction, the shield machine is often trapped underground during subway construction, especially when encountering some soft-on-top-hard-on-bottom, bedrock strata, and water-rich sand and gravel strata. Due to the complexity of the stratum structure, the shield is unevenly stressed in the stratum structure, which can easily lead to collapse. It is also easy for the cutter to wear unevenly or the cutterhead to be locked and unable to rotate due to bedrock or pebble debris, making it more likely to be trapped. Summary of the invention

[0003] The purpose of the present invention is to provide a shield machine escaping from an obstacle by passing through soft upper and hard lower strata, so as to solve the problem proposed in the above background technology that the shield machine is subjected to uneven force in the stratum structure, which easily leads to collapse, and the tool is easily worn eccentrically or the cutter disc is locked and unable to rotate due to bedrock or pebble slag, making it more likely to get into an awkward situation.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a shield machine that escapes from an upper soft and lower hard stratum, comprising a shield machine and a detection hole, a cutter disc is arranged at the top of the shield machine, a soil bin and a middle shield are distributed inside the shield machine, a screw machine is arranged inside the shield machine, a grouting tank is arranged inside the shield machine away from the cutter disc, and a surface passage of the grouting tank is connected to a conveying pipe, and the conveying pipe is respectively connected to the soil bin and the advance grouting hole passage at the top of the shield machine.

[0005] Preferably, the slurry stored in the grouting tank is a lubricating material, and the lubricating material enters the outer surface of the soil bin and the shield machine through the conveying pipe and the advance grouting hole.

[0006] Preferably, a water spray port is provided on the surface of the cutter disc, and the lubricating slurry in the soil bin is sprayed between the cutter disc and the collapse area through the water spray port.

[0007] A shield tunneling method for escaping from an upper soft and lower hard stratum comprises the following steps:

[0008] S1: Preliminary assessment of trapped situation;

[0009] S2: initial escape attempt;

[0010] S3: The cutter disc is reversed and pulled back;

[0011] S4: Escape effectively;

[0012] S5: Normal operation;

[0013] S6: Unable to get out of trouble;

[0014] S7: Drill a hole above the trapped shield tunneling machine;

[0015] S8: Grout through the duct;

[0016] S9: The muck in the soil bin of the shield tunneling machine is discharged by the screw conveyor;

[0017] S10: The slurry in the grouting tank enters the soil bin to complete the replacement;

[0018] S11: The slurry in the soil bin is discharged through the cutter head;

[0019] S12: Make a second attempt to get out of trouble;

[0020] S13: Get out of trouble and carry out overexcavation, and work normally.

[0021] Preferably, the specific operation of S1 is: initially determine the trapped situation of the shield tunneling machine. After personnel enter the bin for inspection, the shield body of the shield tunneling machine is closely attached to the rock surface within the range of 180° above the cutting ring, and the shield body is stuck.

[0022] Preferably, the specific operation of S2 is: the shield stabilizer supports the rock surface, the active articulated cylinder is retracted to make the front shield and the cutter head retreat; at the same time, water is injected into the soil bin to increase the jacking force.

[0023] Preferably, the specific operations of S7 and S8 are: drill a hole at the face of the shield tunneling machine to detect the formation distribution and the size of the collapse cavity, and then backfill the inert slurry according to the size of the collapse cavity and seal the hole.

[0024] Preferably, the specific operation of S10 is: relocate several conveying pipelines located at the shield tail of the shield tunneling machine to the soil bin in the middle shield and the advanced grouting holes at the top of the shield tunneling machine respectively, and continuously inject replacement filler into the soil bin through the conveying pipe until it reaches 3Bar.

[0025] Preferably, the specific operation of S12 is: start the screw conveyor of the shield tunneling machine to discharge the bin, discharge the mixture of the muck in the soil bin and the replacement filler, and simultaneously continuously inject the replacement filler into the soil bin and the advanced grouting holes for muck replacement until the content of pebbles in the discharged muck ≤ 10%, and then start the cutter head of the shield tunneling machine to get out of trouble.

[0026] Preferably, the specific operation of S13 is: after the cutter head of the shield tunneling machine gets out of trouble, stop injecting the replacement filler, relocate the grouting pipeline back to its original position, and after the shield tunneling machine retreats in place, carry out overexcavation work.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] 1. Both replacement fillers and lubricating materials can reduce the friction between the pebble soil and the cutter disc. When the particle size of the slag is further reduced, the damage to the mechanical equipment caused by forced escape can be further avoided, which is safer. Through the mutual coordination of various steps, when encountering some soft upper and hard lower bedrock formations, water-rich sand and gravel formations, the existing cutter disc escape method can effectively solve the problems of low escape efficiency, poor safety and high construction cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the system structure of the present invention;

[0030] Figure 2 It is a schematic diagram of the method steps of the present invention. DETAILED DESCRIPTION

[0031] See also Figure 1-2 , an embodiment provided by the present invention:

[0032] A shield machine for escaping from an upper soft and lower hard stratum comprises a shield machine and a detection hole, wherein a cutter disc is arranged at the top of the shield machine, a soil bin and a middle shield are distributed inside the shield machine, a screw machine is arranged inside the shield machine, a grouting tank is arranged inside the shield machine away from the cutter disc, and a surface passage of the grouting tank is connected with a conveying pipe, which is respectively connected with the soil bin and the advance grouting hole passage at the top of the shield machine, the slurry stored in the grouting tank is a lubricating material, and the lubricating material enters the soil bin and the outer surface of the shield machine through the conveying pipe and the advance grouting hole, a water spraying port is arranged on the surface of the cutter disc, and the lubricating slurry in the soil bin is sprayed between the cutter disc and the collapse area through the water spraying port, and the lubricating material is prepared by mixing sodium bentonite and water in a mass ratio of 1:9; and the plasticized viscosity of the lubricating material is ≥90s.

[0033] A shield tunneling method for escaping from an upper soft and lower hard stratum comprises the following steps:

[0034] S1: Preliminary judgment of the trapped situation. After personnel entered the chamber for investigation, it was found that the shield of the TBM was in close contact with the rock surface within 180° of the upper part of the cut ring, and the shield was stuck;

[0035] S2: Initial escape attempt: the shield stabilizer supports the rock surface, and the active articulated cylinder is retracted to move the front shield and cutterhead backward; at the same time, water is pumped into the soil bin to increase the return force;

[0036] S3: The cutter disc is reversed and pulled back;

[0037] S4: Escape effectively;

[0038] S5: Normal operation;

[0039] S6: Unable to escape;

[0040] S7: The shield was trapped above the drilling hole;

[0041] S8: Through hole grouting, holes are drilled at the tunnel face of the shield machine to detect the stratum distribution and the size of the collapsed cavity, and then the inert slurry is backfilled according to the size of the collapsed hole and the hole is sealed;

[0042] S9: The slag in the shield soil bin is discharged by a screw machine;

[0043] S10: The slurry in the grouting tank enters the soil bin to complete the replacement. Several delivery pipelines located at the tail of the shield machine are moved to the soil bin of the middle shield of the shield machine and the advance grouting holes on the top. The replacement filler is continuously injected into the soil bin through the delivery pipe to 3 Bar.

[0044] S11: The slurry in the soil bin is discharged through the cutter disc;

[0045] S12: Second escape attempt, start the screw machine of the shield machine to discharge the slag and the mixture of replacement filler in the soil bin, and simultaneously continue to inject replacement filler into the soil bin and the advance grouting hole to replace the slag, the components of the replacement filler include water, sand, fly ash and bentonite; wherein: the mass ratio of water, sand, fly ash and bentonite is 480:800:280:320, until the content of pebbles in the discharged slag is ≤10%, start the shield machine cutter head to escape, the escape operation is: rotate the cutter head at a speed of 0.8r / min for one circle, gradually increase the speed of the cutter head to 1.3r / min, and complete the escape when the cutter head torque reaches 3000-4000knm;

[0046] S13: Complete the rescue and expansion, and work normally. After the shield cutter is rescued, stop the injection of replacement filler, and move the grouting pipeline back to its original position. After the shield machine returns to its position, carry out expansion work, and expand the excavation with different cutter heights and gradients, with an expansion volume of 10mm; gradually expand the excavation: 1. After the cutter is installed, the operator manually controls the cutter head, rotates and observes the operation of the cutter head, records the cutter head torque value at this time and uses it as the expansion control value; 2. After confirming that there is no abnormality in the work of the cutter, expand the excavation at a low speed of 0.5-1.0r / min and a low speed of 5mm / min. During the expansion process, focus on the changes in torque, speed, cutter and current ring segment; 3. Every 5-10 centimeters of expansion, personnel enter the warehouse to check the working condition of the cutter, observe whether the cutter is split, whether the rotation is normal, the amount of cutter wear and the expansion of the rock surface.

Claims

1. A shield tunneling escape system for passing through soft upper and hard lower strata, characterized in that, Including: A shield machine and a detection hole. A cutter head is provided at the top of the shield machine. A soil bin and a middle shield are distributed inside the shield machine. A screw conveyor is provided inside the shield machine. A grouting tank is provided inside the shield machine away from the cutter head. A conveying pipe is connected to the surface passage of the grouting tank. The conveying pipe is respectively connected to the soil bin and the advanced grouting holes at the top of the shield machine through passages.

2. A shield tunneling escape system for passing through upper soft and lower hard strata according to claim 1, characterized in that: The slurry stored in the grouting tank is a lubricating material. The lubricating material enters the soil bin and the outer surface of the shield machine through the conveying pipe and the advanced grouting holes.

3. The shield tunneling breakthrough system and method through soft upper and hard lower strata according to claim 1, characterized in that: Spray nozzles are provided on the surface of the cutter head. The lubricating slurry in the soil bin is sprayed between the cutter head and the collapse area through the spray nozzles.

4. A method for a shield to get out of trouble when passing through a soft upper and hard lower stratum, characterized in that, Including the following steps: S1: Preliminary determination of the trapped situation; S2: Preliminary attempt to get out of trouble; S3: Reverse the cutter head and pull the cutter head backward; S4: Effectively get out of trouble; S5: Normal operation; S6: Unable to get out of trouble; S7: Drill a hole above the trapped shield machine; S8: Grout through the hole; S9: The muck in the shield machine soil bin is discharged by the screw conveyor; S10: The slurry in the grouting tank enters the soil bin to complete the replacement; S11: The slurry in the soil bin is discharged through the cutter head; S12: Second attempt to get out of trouble; S13: Complete getting out of trouble and excavation, and normal operation.

5. A method for a shield tunneling machine to get out of trouble when passing through a soft upper and hard lower stratum, characterized in that: The specific operation of S1 is: Make a preliminary determination of the trapped situation of the shield machine. After the personnel enter the bin for investigation, the shield body of the shield machine is closely attached to the rock surface within the range of 180° above the cut ring, and the shield body is stuck.

6. A method for a shield tunneling machine to break through the soft upper and hard lower strata, according to claim 4, characterized in that: The specific operation of S2 is: The shield body stabilizer supports the rock surface, retracts the active hinge cylinder, and makes the front shield and the cutter head retreat; at the same time, water is injected into the soil bin to increase the jacking force.

7. A shield tunneling escape method for passing through upper soft and lower hard strata according to claim 4, characterized in that: The specific operations of S7 and S8 are: Drill a hole at the shield machine face, detect the formation distribution and the size of the collapse cavity, and then backfill the inert slurry according to the size of the collapse hole and seal the hole.

8. A method for a shield to escape from a soft upper and hard lower stratum during tunneling, as claimed in claim 4, wherein: The specific operation of S10 is: Migrate several conveying pipelines located at the shield tail of the shield machine to the soil bin in the middle shield and the advanced grouting holes at the top of the shield machine respectively, and continuously inject replacement filler into the soil bin through the conveying pipe until 3 Bar.

9. A shield tunneling escape method for passing through upper soft and lower hard strata according to claim 4, characterized in that: The specific operation of S12 is: Start the screw conveyor of the shield machine to discharge the bin, discharge the mixture of the muck in the soil bin and the replacement filler, and continuously inject the replacement filler into the soil bin and the advanced grouting holes synchronously for muck replacement until the content of pebbles in the discharged muck ≤ 10%, and then start the cutter head of the shield machine to get out of trouble.

10. A method for a shield tunneling machine to escape from a soft upper and hard lower stratum, according to claim 4, characterized in that: The specific operation of S13 is: After the cutter head of the shield machine gets out of trouble, stop injecting the replacement filler, relocate the grouting pipeline, and after the shield machine retreats in place, carry out the excavation work.

Images