TBM (Tunnel Boring Machine) multi-gripper-shoe regulation and control method adapting to state change of broken

Abstract

The invention discloses a TBM (Tunnel Boring Machine) multi-gripper-shoe regulation and control method adapting to the state change of broken surrounding rock, which comprises the following steps of: mounting a vacuum chuck body on the working surface of a gripper shoe, forming a grouting hole in the side edge of the vacuum chuck body, connecting the grouting hole with a grouting machine, supporting the gripper shoe on the surrounding rock in a single-support mode, starting a TBM machine to tunnel, arranging a measuring point on the surrounding rock, and setting the measuring point on the surrounding rock. Judging whether the surrounding rock is in a completely broken state or not according to the displacement rate of the measuring point, if so, performing support grouting on the broken surrounding rock, calculating friction force between the surrounding rock and the gripper shoe, judging whether the friction force is greater than critical friction force or not, if so, continuing construction, otherwise, enabling the vacuum chuck to be adsorbed on the surrounding rock, measuring the displacement rate of the gripper shoe, and if not, stopping construction. And if the displacement rate is larger than the theoretical displacement rate, the front and rear supporting shoes are supported on the top and the two side walls of the tunnel in a multi-point stress mode, then the construction is continued, and the problems that when the TBM supporting shoes are used for complex geology, the TBM supporting shoes are prone to slipping, and the supporting force between the supporting shoes and surrounding rock is insufficient are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of TBM construction, and relates to a TBM multi-support shoe control method adapting to changes in the state of broken surrounding rocks. Background Art

[0002] With the development of my country's water conservancy and society, people's demand for space is growing, especially underground space. As the development of ground space has become increasingly limited, people's demand and development of underground space has become urgent. As an important underground space development equipment, TBM (full-section tunnel boring machine) is particularly important in complex geological conditions. TBM can complete tunnel construction efficiently and accurately, especially in hard rock and soft rock formations. The application of TBM can effectively improve construction efficiency and quality and reduce the impact on the environment. ‌

[0003] The support mechanism is a key sub-component of the TBM continuous excavation operation. During the advancement of the TBM, the support system extends the gripper to tighten the surrounding rock, providing the force required for the cutterhead to advance and the torque required for the cutterhead to rotate. The gripper is a key component of the support mechanism. The gripper is in contact with the tunnel wall to ensure the stability and safety of the tunnel boring machine during the excavation process. The gripper needs to extend from the core to support the entire machine body and can be flexibly adjusted during the excavation process to adapt to the shape and conditions of different tunnel walls. Therefore, the gripper system needs to have strong support, stability and flexibility, but the existing gripper system is prone to uneven force on the surrounding rock, the side wall cannot be supported, and the gripper support is unstable. Especially for highly abrasive formations and complex geological conditions such as karst and fault fracture zones, the gripper is prone to slipping and the tightening force between the gripper and the surrounding rock is insufficient. Summary of the invention

[0004] The purpose of the present invention is to provide a TBM multi-gripper control method that adapts to changes in the state of broken surrounding rock, thereby solving the problems of slipping of existing TBM grippers when used in complex geology and insufficient tightening force between the grippers and the surrounding rock.

[0005] The technical solution adopted by the present invention is a TBM multi-shoe control method that adapts to the change of the state of the broken surrounding rock, comprising the following steps: Step 1: Install a vacuum cup body on the working surface of the TBM support shoe, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, a grouting hole is provided on the side of the vacuum cup body, the vacuum suction nozzle is connected to a vacuum generating system, and the grouting hole is connected to a grouting machine; Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3, arranging measuring points on the surrounding rock and monitoring the displacement rate of the measuring points; Step 4, assess the degree of surrounding rock crushing according to the displacement rate of the measuring point, and determine whether the surrounding rock is in a completely crushed state. If not, proceed to step 5. If so, start the grouting machine, which transports slurry to the grouting hole, supports and grouts the crushed surrounding rock, and then proceed to step 5; Step 5, calculate the friction force F between the surrounding rock and the gripper to determine whether it is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock. Step 6, measure the displacement rate of the single-support support shoe and compare it with the theoretical displacement rate of the support shoe. If the displacement rate of the support shoe is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the support shoe is greater than the theoretical displacement rate, use the front and rear support shoes to support the top and two side walls of the tunnel at multiple points, and then continue construction.

[0006] The grouting hole is connected to the discharge port of the grouting machine through a grouting pipe, and the slurry is transported to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock.

[0007] Step 3 includes arranging multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, using a total station to monitor the displacement of each measuring point, and then calculating the average displacement rate of these measuring points. v .

[0008] In step 4, determine whether the surrounding rock is in a completely broken state or whether there is a partitioned cracking phenomenon. If not, proceed to step 5. If so, start the grouting machine.

[0009] When the average displacement rate of all measuring points v ≤0.1mm / d, it indicates that the surrounding rock is in a stable and complete state. v ≤0.15mm / d, it indicates that the surrounding rock is in a state of micro-fracture. At this time, the monitoring frequency of the displacement of the measuring point is increased. v When the deformation is less than 0.2 mm / d, it indicates that the surrounding rock is in a state of rapid deformation. At this time, the slurry needs to be prepared and the surrounding rock needs to be grouting supported at any time. v When it is greater than 0.20 mm / d, it indicates that the surrounding rock is in a completely broken state.

[0010] When the displacement rate difference between different measuring points exceeds 0.10 mm / d, and v When ≤0.20mm / d, it indicates that the surrounding rock has zonal cracking.

[0011] The first vibrating screen, the second vibrating screen, the third vibrating screen and the storage bin are installed in sequence at the output end of the TBM belt conveyor. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625mm and 2mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2mm and 20mm. The storage bin is used to receive crushed stones with a particle size greater than 20mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration.

[0012] The grouting machine transports the slurry to the grouting hole. The slurry is a quick-setting slurry containing an accelerating agent.

[0013] In step 5, the friction force F between the surrounding rock and the gripper is calculated as follows:

[0014]

[0015] Where μ is the dynamic friction coefficient, F n is the normal pressure on the surface of the shoe, P is the critical friction force, E is the elastic modulus, I is the contact area between the shoe and the surrounding rock, and L is the length from the contact surface between the shoe and the surrounding rock to the end of the compression rod.

[0016] The vacuum suction cup body is arc-shaped and fits with the working surface of the support shoe. A porous rubber striped adhesive pad is attached to the surface of the vacuum suction cup body. The holes of the porous rubber striped adhesive pad correspond one by one to the vacuum suction nozzle on the vacuum suction cup body.

[0017] The beneficial effects of the present invention are as follows: (1) By installing a vacuum suction cup on the working surface of the gripper, when the friction between the surrounding rock and the gripper is less than the critical friction, the vacuum generation system is turned on to make the vacuum suction cup firmly adsorbed on the surrounding rock, thereby increasing the friction between the surrounding rock and the gripper and preventing the gripper from slipping; (2) By arranging measuring points on the surrounding rock, the degree of surrounding rock fragmentation is evaluated according to the displacement rate of the measuring points. If the surrounding rock is in a completely broken state, support grouting is performed on the broken surrounding rock to improve the stability of the surrounding rock. (3) By measuring the displacement rate of the single-support support shoe and comparing it with the theoretical displacement rate, if the displacement rate of the single-support support shoe is greater than the theoretical displacement rate, the front and rear support shoes are supported at the top and side walls of the tunnel at multiple points. This meets the requirements for the stability and reliability of the support shoes, reduces the maintenance cost of the support shoes, and balances the uneven force between the support shoes and the surrounding rock, thereby improving the tunneling efficiency of the tunnel boring machine in broken surrounding rock. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a flow chart of the TBM multi-gripper control method for adapting to the change of the state of the broken surrounding rock according to the present invention; Figure 2 It is a position relationship diagram (side view) between the vibrating screen and the TBM gripper in the TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock of the present invention; Figure 3 It is a structural schematic diagram of the vacuum suction cup body in the TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to the present invention; Figure 4 is a schematic diagram of the working condition in which four support shoes are supported simultaneously in a tunnel in Embodiment 3 of the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the front and rear TBM support shoes subjected to four-point force in Example 6 of the present invention.

[0019] In the figure, 1. TBM support shoe, 2. vacuum suction cup body, 3. vacuum suction nozzle, 4. grouting hole, 5. grouting pipeline, 6. grouting machine, 7. TBM machine, 8. belt conveyor, 9. first vibrating screen, 10. second vibrating screen, 11. third vibrating screen, 12. storage bin. DETAILED DESCRIPTION

[0020] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Example 1 A TBM multi-gripper control method that adapts to the changing state of the broken surrounding rock, see Figure 1 , including the following steps: Step 1: Install a vacuum cup body on the working surface of the TBM support shoe, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, a grouting hole is provided on the side of the vacuum cup body, the vacuum suction nozzle is connected to a vacuum generating system, and the grouting hole is connected to a grouting machine; Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3, arranging measuring points on the tunnel surrounding rock and monitoring the displacement rate of the measuring points; Step 4, assess the degree of surrounding rock crushing according to the displacement rate of the measuring point, and determine whether the surrounding rock is in a completely crushed state. If not, proceed to step 5. If so, start the grouting machine, which transports slurry to the grouting hole, supports and grouts the crushed surrounding rock, and then proceed to step 5; Step 5, calculate the friction force F between the surrounding rock and the gripper, and determine whether it is greater than the critical friction force. If so, continue construction; if not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock to increase the friction and gripping force between the gripper and the surrounding rock; Step 6, measure the displacement rate of the single-support TBM support shoe and compare it with the theoretical displacement rate of the TBM support shoe. If the displacement rate of the TBM support shoe is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM support shoe is greater than the theoretical displacement rate, use the front and rear TBM support shoes to support the top and two side walls of the tunnel at multiple points, and then continue construction.

[0022] Example 2 A TBM multi-gripper control method adapted to changes in the state of broken surrounding rock comprises the following steps: Step 1: Install a vacuum cup body on the TBM support shoe working surface, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, a grouting hole is provided on the side of the vacuum cup body, the vacuum suction nozzle is connected to a vacuum generating system, and the grouting hole is connected to a grouting machine through a grouting pipe; Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3: Arrange multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, use a total station to monitor the displacement of each measuring point, and then calculate the average displacement rate of these measuring points v ; Step 4: Based on the average displacement rate v Assess the degree of surrounding rock fragmentation and determine whether the surrounding rock is in a completely broken state or whether there is a zonal cracking phenomenon. If not, proceed to step 5. If yes, start the grouting machine, which transports the slurry to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock, and then proceed to step 5. Step 5, calculate the friction force F between the surrounding rock and the gripper to determine whether it is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock. Step 6, measure the displacement rate of the single-support TBM support shoe and compare it with the theoretical displacement rate of the TBM support shoe. If the displacement rate of the TBM support shoe is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM support shoe is greater than the theoretical displacement rate, use the front and rear TBM support shoes to support the tunnel top and both side walls in a three-point force manner, and then continue construction.

[0023] Example 3 A TBM multi-gripper control method adapted to changes in the state of broken surrounding rock comprises the following steps: Step 1, see Figure 2 and Figure 3A vacuum cup body 2 is installed on the working surface of the TBM support shoe 1. A plurality of vacuum suction nozzles 3 are provided in the middle of the vacuum cup body 2. Grouting holes 4 are provided on the side of the vacuum cup body 2. The vacuum suction nozzles are connected to a vacuum generating system. The vacuum generating system is arranged at the position where the support shoe and the auxiliary beam are connected. The grouting holes 4 are connected to a grouting machine 6 through a grouting pipe 5. A first vibrating screen 9, a second vibrating screen 10, a third vibrating screen 11 and a storage bin 12 are sequentially installed at the output end of the belt conveyor 8 of the TBM machine 7. The first vibrating screen 9, the second vibrating screen 10 and the third vibrating screen 11 are all tilted to facilitate the crushed stones on the screen to roll onto the next screen. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625 mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625 mm and 2 mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2 mm and 20 mm. The storage bin 12 is used to receive crushed stones with a particle size greater than 20 mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration to achieve the effect of reasonable recycling of crushed rocks.

[0024] Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3: Arrange multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, use a total station to monitor the displacement of each measuring point, and then calculate the average displacement rate of these measuring points v ; Step 4: Based on the average displacement rate v Assess the degree of surrounding rock fragmentation to determine whether the surrounding rock is in a completely broken state or whether there is a partitioned cracking phenomenon. If not, proceed to step 5. If yes, start the grouting machine 6, which transports the slurry to the grouting hole 4 through negative pressure to complete the support grouting of the broken surrounding rock, and then proceed to step 5; Step 5, calculate the friction force F between the surrounding rock and the gripper to determine whether it is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock. Step 6: Measure the displacement rate of the single-support TBM gripper and compare it with the theoretical displacement rate of the TBM gripper. If the displacement rate of the TBM gripper is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM gripper is greater than the theoretical displacement rate, use the front and rear TBM grippers to support the top and side walls of the tunnel at multiple points, and then continue construction. See Figure 4 , four support shoes are put into use at the same time, thereby improving the stability of TBM construction.

[0025] Example 4 A TBM multi-gripper control method adapted to changes in the state of broken surrounding rock comprises the following steps: Step 1: Install a vacuum cup body on the TBM support shoe working surface, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, a grouting hole is provided on the side of the vacuum cup body, the vacuum suction nozzle is connected to a vacuum generating system, and the grouting hole is connected to a grouting machine through a grouting pipe; The vacuum suction cup body is arc-shaped and fits well with the working surface of the support shoe. A porous rubber striped adhesive pad is applied to the surface of the vacuum suction cup body. The holes of the porous rubber striped adhesive pad correspond one by one to the vacuum suction nozzle on the vacuum suction cup body. The porous rubber striped adhesive pad has good elasticity and can fill the tiny gap between the suction cup and the surface of the adsorbed object. When the suction cup fits the object, the porous rubber striped adhesive pad deforms under the action of pressure and fits tightly to the unevenness of the object's surface, effectively preventing air leakage and allowing the vacuum system to work normally.

[0026] The first vibrating screen, the second vibrating screen, the third vibrating screen and the storage bin are installed in sequence at the output end of the TBM belt conveyor. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625mm and 2mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2mm and 20mm. The storage bin is used to receive crushed stones with a particle size greater than 20mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration to achieve the effect of reasonable recycling of crushed rocks.

[0027] Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3: Arrange multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, use a total station to monitor the displacement of each measuring point, and then calculate the average displacement rate of these measuring points v ; Step 4: Based on the average displacement rate v Assess the degree of surrounding rock fragmentation and determine whether the surrounding rock is in a completely broken state or whether there is a zonal cracking phenomenon. If not, proceed to step 5. If yes, start the grouting machine, which transports the slurry to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock, and then proceed to step 5. Step 5, calculate the friction force F between the surrounding rock and the gripper to determine whether it is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock. Step 6, measure the displacement rate of the single-support TBM support shoe and compare it with the theoretical displacement rate of the TBM support shoe. If the displacement rate of the TBM support shoe is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM support shoe is greater than the theoretical displacement rate, use the front and rear TBM support shoes to support the top and two side walls of the tunnel at multiple points, and then continue construction.

[0028] Example 5 A TBM multi-gripper control method adapted to changes in the state of broken surrounding rock comprises the following steps: Step 1: Install a vacuum cup body on the TBM support shoe working surface, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, a grouting hole is provided on the side of the vacuum cup body, the vacuum suction nozzle is connected to a vacuum generating system, and the grouting hole is connected to a grouting machine through a grouting pipe; The vacuum suction cup body is arc-shaped and fits well with the working surface of the support shoe. A porous rubber striped adhesive pad is applied to the surface of the vacuum suction cup body. The holes of the porous rubber striped adhesive pad correspond one by one to the vacuum suction nozzle on the vacuum suction cup body. The porous rubber striped adhesive pad has good elasticity and can fill the tiny gap between the suction cup and the surface of the adsorbed object. When the suction cup fits the object, the porous rubber striped adhesive pad deforms under the action of pressure and fits tightly to the unevenness of the object's surface, effectively preventing air leakage and allowing the vacuum system to work normally.

[0029] The first vibrating screen, the second vibrating screen, the third vibrating screen and the storage bin are installed in sequence at the output end of the TBM belt conveyor. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625mm and 2mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2mm and 20mm. The storage bin is used to receive crushed stones with a particle size greater than 20mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration to achieve the effect of reasonable recycling of crushed rocks.

[0030] Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3: Arrange multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, use a total station to monitor the displacement of each measuring point, and then calculate the average displacement rate of these measuring points v ; Step 4: Based on the average displacement rate vAssess the degree of surrounding rock fragmentation and determine whether the surrounding rock is in a completely broken state or whether there is a zonal cracking phenomenon. If not, proceed to step 5. If yes, start the grouting machine, which transports the slurry to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock, and then proceed to step 5. Step 5, calculate the friction force F between the surrounding rock and the gripper. The calculation process is as follows:

[0031]

[0032] Where μ is the dynamic friction coefficient, F n is the normal pressure on the surface of the shoe, P is the critical friction force, E is the elastic modulus, I is the contact area between the shoe and the surrounding rock, and L is the length from the contact surface between the shoe and the surrounding rock to the end of the compression rod.

[0033] Determine whether the friction force F between the surrounding rock and the gripper is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adhere to the surrounding rock. Step 6, measure the displacement rate of the single-support TBM support shoe and compare it with the theoretical displacement rate of the TBM support shoe. If the displacement rate of the TBM support shoe is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM support shoe is greater than the theoretical displacement rate, use the front and rear TBM support shoes to support the tunnel top and both side walls in a three-point force manner, and then continue construction.

[0034] Example 6 A TBM multi-gripper control method adapted to changes in the state of broken surrounding rock comprises the following steps: Step 1: Install a vacuum cup body on the working surface of the TBM gripper, wherein a plurality of vacuum suction nozzles are provided in the middle of the vacuum cup body, grouting holes are provided on the side of the vacuum cup body, and the grouting holes are located on opposite sides of the TBM gripper. The vacuum suction nozzles are connected to a vacuum generating system, and the grouting holes are connected to a grouting machine through a grouting pipe; The vacuum suction cup body is arc-shaped and fits well with the working surface of the support shoe. A porous rubber striped adhesive pad is applied to the surface of the vacuum suction cup body. The holes of the porous rubber striped adhesive pad correspond one by one to the vacuum suction nozzle on the vacuum suction cup body. The porous rubber striped adhesive pad has good elasticity and can fill the tiny gap between the suction cup and the surface of the adsorbed object. When the suction cup fits the object, the porous rubber striped adhesive pad deforms under the action of pressure and fits tightly to the unevenness of the object's surface, effectively preventing air leakage and allowing the vacuum system to work normally.

[0035] The first vibrating screen, the second vibrating screen, the third vibrating screen and the storage bin are installed in sequence at the output end of the TBM belt conveyor. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625mm and 2mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2mm and 20mm. The storage bin is used to receive crushed stones with a particle size greater than 20mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration to achieve the effect of reasonable recycling of crushed rocks.

[0036] Step 2: Support the TBM support shoe on the tunnel surrounding rock with a single support method, then start the TBM machine to excavate the tunnel, and at this time, the vacuum generating system and the grouting machine are in a closed state; Step 3: Arrange multiple measuring points on the surrounding rock at different locations at the same depth of the tunnel, use a total station to monitor the displacement of each measuring point, and then calculate the average displacement rate of these measuring points v ; Step 4: Based on the average displacement rate v Assess the degree of surrounding rock fragmentation when the average displacement rate v ≤0.1mm / d, it indicates that the surrounding rock is in a stable and complete state. v ≤0.15mm / d, it indicates that the surrounding rock is in a state of micro-fracture. At this time, the monitoring frequency of the displacement of the measuring point is increased. v When the deformation is less than 0.2 mm / d, it indicates that the surrounding rock is in a state of rapid deformation. At this time, the slurry needs to be prepared and the surrounding rock needs to be grouting supported at any time. v When it is greater than 0.20 mm / d, it indicates that the surrounding rock is in a completely broken state.

[0037] The slurry is a quick-setting slurry, which is composed of a mixture of water, cement, quick-setting agent and rocks in a storage barrel and can solidify in a short time.

[0038] When the displacement rate difference between different measuring points exceeds 0.10 mm / d, and v When ≤0.20mm / d, it indicates that the surrounding rock has zonal cracking.

[0039] Determine whether the surrounding rock is in a completely broken state or whether there is a zonal cracking phenomenon. If not, proceed to step 5. If yes, start the grouting machine, which quickly transports the slurry to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock around the grouting hole, effectively avoiding the aggravation of the local surrounding rock crushing effect and the uneven force between the support shoe and the surrounding rock, thereby improving the stability of the support shoe, and then proceed to step 5; Step 5, calculate the friction force F between the surrounding rock and the gripper. The calculation process is as follows:

[0040]

[0041] Where μ is the dynamic friction coefficient, F n is the normal pressure on the surface of the shoe, P is the critical friction force, E is the elastic modulus, I is the contact area between the shoe and the surrounding rock, and L is the length from the contact surface between the shoe and the surrounding rock to the end of the compression rod.

[0042] Determine whether the friction force F between the surrounding rock and the gripper is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adhere to the surrounding rock. Step 6: Measure the displacement rate of the single-support TBM gripper and compare it with the theoretical displacement rate of the TBM gripper. If the displacement rate of the TBM gripper is less than or equal to the theoretical displacement rate, continue construction. If the displacement rate of the TBM gripper is greater than the theoretical displacement rate, use the front and rear TBM grippers to support the tunnel top and both side walls in a four-point force manner, and then continue construction. See Figure 5 The two front support shoes are supported on the top and side wall of the right side of the tunnel, and the two rear support shoes are supported on the top and side wall of the left side of the tunnel, thereby increasing the holding force and improving the excavation efficiency of the tunnel boring machine in the broken surrounding rock.

Claims

1. A TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock, characterized in that: The following steps are involved: Step 1, installing a vacuum suction cup body (2) on the working surface of the TBM support shoe (1), wherein a plurality of vacuum suction nozzles (3) are provided in the middle of the vacuum suction cup body (2), a grouting hole (4) is provided on the side of the vacuum suction cup body (2), the vacuum suction nozzle (3) is connected to a vacuum generating system, and the grouting hole (4) is connected to a grouting machine (6); Step 2, using a single support method to support the TBM support shoe (1) on the tunnel surrounding rock, and then starting the TBM machine to excavate the tunnel, at which time the vacuum generating system and the grouting machine are in a closed state; Step 3, arranging measuring points on the surrounding rock and monitoring the displacement rate of the measuring points; Step 4, evaluating the degree of surrounding rock crushing according to the displacement rate of the measuring point, and determining whether the surrounding rock is in a completely crushed state. If not, proceed to step 5. If so, start the grouting machine (6), which transports slurry to the grouting hole (4) to support and grout the crushed surrounding rock, and then proceed to step 5; Step 5, calculate the friction force F between the surrounding rock and the gripper to determine whether it is greater than the critical friction force. If so, continue construction. If not, start the vacuum generation system to make the vacuum suction cup adsorb on the surrounding rock. Step 6, measure the displacement rate of the single-support support shoe and compare it with the theoretical displacement rate of the TBM support shoe. If the support shoe displacement rate is less than or equal to the theoretical displacement rate, continue construction. If the support shoe displacement rate is greater than the theoretical displacement rate, use the front and rear support shoes to support the top and side walls of the tunnel at multiple points, and then continue construction.

2. The TBM multi-gripper control method adapted to the state change of the broken surrounding rock according to claim 1 is characterized in that: The grouting hole is connected to the discharge port of the grouting machine through a grouting pipe, and the slurry is transported to the grouting hole through negative pressure to complete the support grouting of the broken surrounding rock.

3. The TBM multi-gripper control method adapted to the state change of the broken surrounding rock according to claim 1 is characterized in that: The step 3 includes arranging multiple measuring points on the surrounding rock at different positions at the same depth of the tunnel, using a total station to monitor the displacement of each measuring point, and then calculating the average displacement rate of these measuring points. v .

4. The TBM multi-gripper control method adapted to the state change of the broken surrounding rock according to claim 3 is characterized in that: In step 4, it is determined whether the surrounding rock is in a completely broken state or whether there is a partitioned cracking phenomenon. If not, proceed to step 5. If so, start the grouting machine.

5. The TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to claim 4 is characterized in that: When the average displacement rate of the measuring point v ≤0.1mm / d, it indicates that the surrounding rock is in a stable and complete state. v ≤0.15mm / d, it indicates that the surrounding rock is in a state of micro-fracture. At this time, the monitoring frequency of the displacement of the measuring point is increased. v When the deformation is less than 0.2 mm / d, it indicates that the surrounding rock is in a state of rapid deformation. At this time, the slurry needs to be prepared and the surrounding rock needs to be grouting supported at any time. v When it is greater than 0.20 mm / d, it indicates that the surrounding rock is in a completely broken state.

6. The TBM multi-gripper control method adapted to the state change of the broken surrounding rock according to claim 5 is characterized in that: When the displacement rate difference between different measuring points exceeds 0.10 mm / d, and v When ≤0.20mm / d, it indicates that the surrounding rock has zonal cracking.

7. The TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to claim 6 is characterized in that: The first vibrating screen, the second vibrating screen, the third vibrating screen and the storage bin are installed in sequence at the output end of the TBM belt conveyor. A storage barrel is placed at the bottom of each vibrating screen. The first vibrating screen is used to screen small-sized rocks with a particle size less than 0.0625mm, the second vibrating screen is used to screen medium-sized rocks with a particle size between 0.0625mm and 2mm, and the third vibrating screen is used to screen coarse-sized rocks with a particle size between 2mm and 20mm. The storage bin is used to receive crushed stones with a particle size greater than 20mm. When configuring the slurry, the rocks in the storage barrel are directly used for slurry configuration.

8. The TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to claim 1 or 7, characterized in that: The grouting machine transports the slurry to the grouting hole. The slurry is a quick-setting slurry containing an accelerating agent.

9. The TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to claim 1, characterized in that: In step 5, the friction force F between the surrounding rock and the gripper is calculated, and the calculation process is as follows: Where μ is the dynamic friction coefficient, F n is the normal pressure on the surface of the shoe, P is the critical friction force, E is the elastic modulus, I is the contact area between the shoe and the surrounding rock, and L is the length from the contact surface between the shoe and the surrounding rock to the end of the compression rod.

10. The TBM multi-gripper control method adapted to the change of the state of the broken surrounding rock according to claim 1, characterized in that: The vacuum suction cup body is arc-shaped and fits with the working surface of the support shoe. A porous rubber striped adhesive pad is attached to the surface of the vacuum suction cup body. The holes of the porous rubber striped adhesive pad correspond one by one to the vacuum suction nozzle on the vacuum suction cup body.

Images