Rapid tunneling construction method of TBM earth pressure balance double-mode double-shield shield tunneling machine in water-rich fault zone stratum

Abstract

The invention discloses a rapid tunneling construction method of a TBM earth pressure balance dual-mode dual-shield shield tunneling machine in a water-rich fault zone stratum, and belongs to the technical field of tunnel construction, and the rapid tunneling construction method comprises the following steps: S1, geological exploration and fault zone solidification are carried out in advance, and grouting holes are formed in the periphery of a fault zone to complete solidification; s2, advanced geological exploration and grouting; s3, mode switching and muddy water treatment; and S4, tunneling is conducted in soft rock of the water-rich fault zone stratum. According to the method, detailed geological exploration is carried out in advance, information of a fracture layer is comprehensively excavated, the fracture zone is solidified, the stability of the fracture zone is improved, and favorable conditions are created for subsequent tunneling construction; advanced grouting is conducted through the proportioned grouting liquid, rapid solidification can be achieved, the strength is high, a waterproof curtain is formed, and underground water inrush and stratum collapse are effectively prevented; by conducting fault zone solidification and advanced grouting in advance, broken stone falling in the shield tunneling process is reduced, frictional resistance caused by surrounding rock to a shield shell is reduced, and the whole shield can be propelled forwards conveniently.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a method for fast excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum. Background Art

[0002] In tunnel construction, the water-rich fault zone stratum is a typical large fault with the characteristics of large fault zone width, complex rock properties, low surrounding rock strength, and abnormal ground stress. Affected by the structure, the rock mass is relatively broken, and it is very easy to cause problems such as arch collapse, water and mud gushing, and large deformation during construction.

[0003] Conventional top half excavation method and segmented excavation method are inefficient, have limited application scenarios, and are not suitable for complex geological conditions. With the rapid development of underground engineering, TBM method has made great progress in tunnel engineering. Among them, the earth pressure balance dual-mode dual-shield shield machine has two excavation modes and has a wider range of strata adaptability compared to open TBM and single-shield TBM.

[0004] However, when the earth pressure balance shield machine encounters water-rich fault zone strata, due to the complex geological conditions, there will be risks of landslides, machine jams, and water gushing, which will seriously restrict the construction progress and even cause damage to machinery and equipment, casualties, and bring huge challenges to tunnel construction.

[0005] Therefore, it is of great practical significance to develop a construction method for rapid excavation of an earth pressure balance shield machine in water-rich fault zone strata. Summary of the invention

[0006] The object of the present invention is to provide a method for rapid excavation construction of a TBM earth pressure balance dual-mode dual-shield shield machine in a water-rich fault zone stratum, so as to solve the problems existing in the background technology.

[0007] The objective of the present invention is achieved through the following technical solutions: A method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield shield machine in a water-rich fault zone stratum comprises the following steps: S1: advance geological exploration and fracture zone solidification; Step S1 includes sub-steps S11 and S12; S11: Obtain accurate geological information through detection equipment and analyze exploration data with geological analysis software; S12: Based on the data from S11, targeted grouting holes were arranged around the fault zone, and sleeve valve tube grouting was used to complete the solidification.

[0008] S2: advance geological exploration and grouting; Step S2 includes sub-steps S21-S23; S21: Install an advanced electrical geological detector on the dual-mode dual-shield TBM to predict the geological conditions ahead of the tunnel face in real time; S22: According to the detection results of S21, the central grouting hole is first determined, and then a grouting hole is made every 2m in an umbrella-shaped layout. The grouting depth exceeds the depth of the unfavorable geological body from the tunnel face by 1~2m. The grouting materials are sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6~0.61: 0.11~0.12: 0.08~0.1: 0.1~0.11: 0.8~0.1, the water-cement ratio is 0.22~0.25, the water reducer content is 1.05%~1.2% of the total mass, the thickener content is 0.03%~0.05% of the total mass, and the grouting pressure ranges from 1~3MPa; S23: After the grouting liquid solidifies, an inspection hole is made between every two adjacent grouting holes to check the consolidation effect of the poor stratum.

[0009] S3: Mode switching and adding weak mud water device, switch the shield machine mode to earth pressure balance shield mode, adjust the soil bin pressure, cutter head speed, thrust and propulsion speed according to geological conditions and previous detection results, realize earth pressure balance control and avoid soil collapse; in terms of mud water treatment, by adding weak mud water device, the mud water generated during excavation is quickly separated and treated, and the treated mud water is recycled, which not only saves water resources but also reduces pollution to the environment; S4: Excavation in soft rock in water-rich fault zone formations.

[0010] Furthermore, the detection equipment in step S11 is a geological radar, a seismic wave detector, etc., and the geological analysis software is FLAC3D, PLAXIS, etc.

[0011] Further, in step S12, the sleeve valve pipe grouting adopts multi-component slurry grouting, and the slurry adopts sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6~0.61: 0.11~0.12: 0.08~0.1: 0.1~0.11: 0.8~0.1, the water reducer content is 1.05%~1.2% of the total mass, and the thickener content is 0.03%~0.05% of the total mass. The drilling holes are arranged in a plum blossom shape, with a hole spacing of 2m×2m and a hole diameter of 100mm. The sleeve valve pipe is buried in the drilling holes. The device is constructed by a screw grouting device, and active bentonite and early-setting and early-strength cement are poured as casing materials between the outer side of the sleeve valve tube device and the wall of the drilled hole. After 48 hours of grouting of the casing material, a double-plug tube is placed along the inner side of the sleeve valve tube, and the double-plug tube is fixed to the inner wall of the sleeve valve tube device by pressurizing. First, grouting is carried out along the lower end of the sleeve valve tube. The grouting pressure of the first grouting hole in the skip hole construction is 0.2-0.3MPa, and the grouting pressure of the subsequent supplementary grouting holes is 0.3-0.4MPa. The interval time of grouting of adjacent holes is greater than 24 hours.

[0012] Furthermore, in step S22, if there are both a water-rich area and a weak fracture zone in front of the tunnel face, a grouting hole is made every 1 m.

[0013] Furthermore, in step S3, for deep groundwater-rich strata, the shield machine soil bin pressure control is calculated according to the groundwater pressure, and the calculation formula is P=ρgh; Where: P is pressure; ρ is liquid density; g is gravitational acceleration; h is the height difference from the groundwater level to the middle of the tunnel.

[0014] Further, step S4 includes sub-steps S41 and S42; S41: The active mixing technology in the silo is used to fully mix and stir the slag in the silo, improve the fluidity and uniformity of the slag, and thus facilitate the discharge of the slag; S42: According to the soft rock characteristics of the strata in the water-rich fault zone and the excavation requirements, engineering debris is added to the foaming agent for immersion tests, and the dispersion effect of foaming agents with different proportions on the mud cake is analyzed to obtain the best dispersant dilution multiple that meets the excavation control requirements.

[0015] Furthermore, in step S42, a calcium-magnesium ion resistant earth pressure balance shield foaming agent is used, and its formula is: 46.1% to 64.2% of a surfactant, 8.6% to 13.9% of a foam stabilizer, 6.7% to 9.8% of a thickener, 11.9% to 21.8% of a sodium phosphate buffer, 3.7% to 5.3% of a preservative, and the balance is water.

[0016] Furthermore, step S4 also includes sub-S43, selecting the air pressure auxiliary mode, using the air compressor to inject compressed air into the soil chamber to balance the excavation surface together with the slag in the chamber that has not yet filled up.

[0017] The beneficial effects of the present invention are: 1) Carry out detailed geological surveys in advance, comprehensively identify the specific location, characteristics and other information of the fault layer, and solidify the fault zone to improve the stability of the fault zone and create favorable conditions for subsequent excavation construction.

[0018] 2) The grouting liquid of the present invention can be used for advanced grouting, which can solidify quickly and has high strength, forming a water-proof curtain to effectively prevent the influx of groundwater and the collapse of the stratum.

[0019] 3) According to the geological conditions and preliminary exploration results, adjust the shield machine mode switching to achieve earth pressure balance control and avoid soil collapse. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flow chart of a method for rapid excavation construction of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0022] See also Figure 1 , the present invention provides a technical solution: like Figure 1 A method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield shield machine in a water-rich fault zone stratum comprises the following steps: S1: advance geological exploration and fracture zone solidification; Step S1 includes sub-steps S11 and S12; S11: Obtain accurate geological information through detection equipment and analyze exploration data with geological analysis software; Furthermore, the detection equipment in step S11 is a geological radar, a seismic wave detector, etc., and the geological analysis software is FLAC3D, PLAXIS, etc.

[0023] S12: Based on the data from S11, targeted grouting holes were arranged around the fault zone, and sleeve valve tube grouting was used to complete the solidification.

[0024] Specifically, the sleeve valve pipe grouting adopts multi-component slurry grouting, and the slurry adopts sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6-0.61: 0.11-0.12: 0.08-0.1: 0.1-0.11: 0.8-0.1, the water reducer content is 1.05%-1.2% of the total mass, and the thickener content is 0.03%-0.05% of the total mass. The drilling holes are arranged in a plum blossom shape, with a hole spacing of 2m×2m and a hole diameter of 100mm. The sleeve valve pipe device is buried in the drilling holes, and active bentonite and early setting and early strength cement are poured between the outer side of the sleeve valve pipe device and the drilling hole wall as casing materials through screw grouting equipment. 48 hours after the grouting of the shell material is completed, a double plug tube is placed along the inside of the sleeve valve tube, and the double plug tube is fixed to the inner wall of the sleeve valve tube device by pressurizing. First, grouting is carried out along the lower end of the sleeve valve tube. The grouting pressure of the first grouting hole in the skip hole construction is 0.2~0.3MPa, and the grouting pressure of the subsequent supplementary grouting holes is 0.3~0.4MPa. The interval time between grouting of adjacent holes is greater than 24 hours.

[0025] Through step S1, a detailed geological survey is carried out in advance to comprehensively survey the specific location, characteristics and other information of the fault layer. For the corresponding area of ​​the fault layer, the pumping and drainage work is strengthened to reduce the water content in the stratum. On the ground, high-strength grouting materials are used to solidify the fault zone in the corresponding position area. Through sleeve valve pipe grouting, a multi-component slurry grouting method is adopted. The drilling holes are arranged in a plum blossom shape, with a hole spacing of 2m×2m and a hole diameter of 100mm. Through sleeve valve pipe grouting, the stability of the fault zone can be improved, creating favorable conditions for subsequent excavation construction.

[0026] S2: advance geological exploration and grouting; Step S2 includes sub-steps S21-S23; S21: Install an advanced electrical geological detector on the dual-mode dual-shield TBM to predict the geological conditions ahead of the tunnel face in real time; S22: According to the detection results of S21, first determine the central grouting hole, and then make a grouting hole every 2m in an umbrella-shaped layout. If there are both water-rich areas and weak fracture zones in front of the tunnel face, make a grouting hole every 1m, and the grouting depth exceeds the depth of the unfavorable geological body from the tunnel face by 1~2m; S23: After the grouting liquid solidifies, an inspection hole is made between every two adjacent grouting holes to check the consolidation effect of the poor stratum.

[0027] Through step S2, when the shield machine approaches the corresponding fault layer, high-strength grouting material with accurate and fast time setting is used for advanced grouting. This grouting material can solidify in a short time to form a water-proof curtain, effectively preventing the influx of groundwater and the collapse of the stratum.

[0028] The advanced electrical geological detector can detect the geological changes ahead in advance, including the distribution of rock layers, the location of faults, the conditions of groundwater, etc. By analyzing the detection data, construction personnel can adjust the construction plan in time and take corresponding measures to ensure the safety and smooth progress of the construction.

[0029] At the same time, in step S22, the ratio of grouting materials and grouting pressure are strictly controlled to ensure the best grouting effect. The main materials are sulphoaluminate cement, polyacrylate emulsion, fly ash, mineral powder, and on-site abandoned concrete slag, wherein the solid content of polyacrylate emulsion is 55%. Through field tests, the optimal ratio of grouting materials is studied, and the strength, fluidity, and setting time curves of the grouting consolidation body under different ratios are obtained. The optimal ratio is determined by the entropy weight method of the multi-index optimization algorithm. The grouting material under the optimal ratio has the excellent characteristics of controllable setting time and high strength. The final grouting material is sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6~0.61: 0.11~0.12: 0.08~0.1: 0.1~0.11: 0.8~0.1, the water-cement ratio is 0.22~0.25, the water reducer content is 1.05%~1.2% of the total mass, the thickener content is 0.03%~0.05% of the total mass, and the grouting pressure ranges from 1~3MPa.

[0030] S3: Mode switching and adding weak mud water device, switch the shield machine mode to earth pressure balance shield mode, adjust the soil bin pressure, cutter head speed, thrust and propulsion speed according to the geological conditions and previous detection results, realize earth pressure balance control and avoid soil collapse. Specifically, for deep strata with abundant groundwater, the shield machine soil bin pressure control is generally calculated with reference to the groundwater pressure, and the calculation formula is P=ρgh; Where: P is pressure; ρ is liquid density; g is gravitational acceleration; h is the height difference from the groundwater level to the middle of the tunnel.

[0031] Taking h=40m as an example, P=4.0bar is obtained. Generally, 0.2bar additional pressure is added on this basis, that is, the shield machine soil bin pressure control value is P=4.2bar. The main parameters are controlled as follows: soil bin pressure 4.1~4.3bar; total thrust 3000~3600t; cutter head speed 1.0~1.2r / min; cutter head torque 5.5~6.3MN·m; excavation speed 20~25mm / min.

[0032] The weak mud water device is a prior art. Refer to the Chinese patented mud water TBM and mud water balance shield machine and control method thereof with authorization announcement number CN109252871A, in which the mobile weak mud water device includes a mud water storage tank, a pumping system, a filtering system and a control system. The mud water storage tank is used to store the prepared mud water, the pumping system is responsible for transporting the mud water to the excavation face of the shield machine, and the filtering system is used to filter and purify the discharged mud water to realize the recycling of the mud water. The control system can realize the automatic control of the entire device to ensure the stability and reliability of its operation.

[0033] By adding a weak mud and water device, the mud and water generated during the excavation process can be quickly separated and treated, and the treated mud and water can be recycled.

[0034] S4: Excavation in soft rock of water-rich fault zone formation; When excavating in the water-rich fault zone, due to the complex geological conditions, the crushed stones will cause great friction between the shield shell and the surrounding rock, making it impossible for the shield to move forward as a whole. This solution solidifies the fault zone in advance and performs advanced grouting to bond and solidify the crushed stones to a certain extent, thereby reducing the falling of crushed stones during the shield excavation process, reducing the friction caused by the surrounding rock to the shield shell, and facilitating the overall forward movement of the shield.

[0035] Further, step S4 includes sub-steps S41 and S42, S41: The active mixing technology in the silo is used to fully mix and stir the slag in the silo, improve the fluidity and uniformity of the slag, and thus facilitate the discharge of the slag; S42: According to the soft rock characteristics of the strata in the water-rich fault zone and the excavation requirements, engineering debris is added to the foaming agent for immersion tests, and the dispersion effect of foaming agents with different proportions on the mud cake is analyzed to obtain the best dispersant dilution multiple that meets the excavation control requirements.

[0036] Furthermore, in step S42, a calcium-magnesium ion resistant earth pressure balance shield foaming agent is used, and its formula is: 46.1% to 64.2% of a surfactant, 8.6% to 13.9% of a foam stabilizer, 6.7% to 9.8% of a thickener, 11.9% to 21.8% of a sodium phosphate buffer, 3.7% to 5.3% of a preservative, and the balance is water.

[0037] By using appropriate foaming agents, the viscosity and friction of the slag can be effectively reduced and the excavation efficiency can be improved.

[0038] Furthermore, step S4 also includes sub-S43, selecting the air pressure auxiliary mode, using the air compressor to inject compressed air into the soil chamber to balance the excavation surface together with the slag in the chamber that has not yet filled up.

[0039] Through the above technical solution, there is a part of the open surface on the upper part of the excavation face during the excavation process, and the air pressure can penetrate into the pores of the rock and soil. When the air pressure occupies the water space in the pores of the rock and soil, it can control the influx of groundwater into the soil compartment to achieve the balance of water pressure on the excavation face. According to the surface environment, propulsion parameters and other conditions, the half-chamber, under-pressure air pressure-assisted mode is selected for propulsion. This air pressure-assisted mode can effectively reduce the propulsion resistance of the shield machine, increase the excavation speed, and at the same time reduce the disturbance to the stratum.

[0040] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield shield machine in a water-rich fault zone stratum, characterized in that: The following steps are involved: S1: advance geological exploration and fracture zone solidification; Step S1 includes sub-steps S11 and S12; S11: Obtain accurate geological information through detection equipment and analyze exploration data with geological analysis software; S12: Combined with the data from S11, targeted grouting holes were arranged around the fault zone, using sleeve valve pipe grouting method; S2: advance geological exploration and grouting; Step S2 includes sub-steps S21-S23; S21: Install an advanced electrical geological detector on the dual-mode dual-shield TBM to predict the geological conditions ahead of the tunnel face in real time; S22: According to the detection results of S21, the central grouting hole is first determined, and then a grouting hole is made every 2m in an umbrella-shaped layout. The grouting depth exceeds the depth of the unfavorable geological body from the tunnel face by 1~2m. The grouting materials are sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6~0.61: 0.11~0.12: 0.08~0.1: 0.1~0.11: 0.8~0.1, the water-cement ratio is 0.22~0.25, the water reducer content is 1.05%~1.2% of the total mass, the thickener content is 0.03%~0.05% of the total mass, and the grouting pressure ranges from 1~3MPa; S23: After the grouting liquid solidifies, an inspection hole is made between every two adjacent grouting holes to check the consolidation effect of the poor stratum; S3: Mode switching and adding weak mud water device, switch the shield machine mode to earth pressure balance shield mode, adjust the soil bin pressure, cutter head speed, thrust and propulsion speed according to geological conditions and previous detection results, realize earth pressure balance control and avoid soil collapse; add weak mud water device to quickly separate and treat the mud water generated during excavation, and recycle the treated mud water; S4: Excavation in soft rock in water-rich fault zone formations.

2. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1 is characterized in that: The detection equipment in step S11 is a geological radar, a seismic wave detector, etc., and the geological analysis software is FLAC3D, PLAXIS, etc.

3. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1, characterized in that: In step S12, the sleeve valve pipe grouting adopts multi-component slurry grouting, and the slurry adopts sulphoaluminate cement: ordinary silicate cement: fly ash: mineral powder: concrete soil residue = 0.6~0.61: 0.11~0.12: 0.08~0.1: 0.1~0.11: 0.8~0.1, the water reducer content is 1.05%~1.2% of the total mass, and the thickener content is 0.03%~0.05% of the total mass. The drilling holes are arranged in a plum blossom shape, with a hole spacing of 2m×2m and a hole diameter of 100mm. The sleeve valve pipe device is buried in the drilling holes. , active bentonite and early-setting and early-strength cement are poured as casing materials between the outer side of the sleeve valve tube device and the wall of the drilled hole through screw grouting equipment. 48 hours after the grouting of the casing material is completed, a double plug tube is placed along the inner side of the sleeve valve tube, and the double plug tube is fixed to the inner wall of the sleeve valve tube device by pressurizing. First, grouting is carried out along the lower end of the sleeve valve tube. The grouting pressure of the first grouting hole in the skip hole construction is 0.2-0.3MPa, and the grouting pressure of the subsequent supplementary grouting holes is 0.3-0.4MPa. The interval time between grouting of adjacent holes is greater than 24 hours.

4. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1, characterized in that: In step S22, if there are both a water-rich area and a weak fracture zone in front of the tunnel face, a grouting hole is made every 1 m.

5. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1, characterized in that: In step S3, for deep strata with abundant groundwater, the shield machine soil bin pressure control is calculated according to the groundwater pressure, and the calculation formula is P=ρgh; Where: P is pressure; ρ is liquid density; g is gravitational acceleration; h is the height difference from the groundwater level to the middle of the tunnel.

6. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1, characterized in that: Step S4 includes sub-steps S41 and S42; S41: Adopt active mixing technology in the silo to fully mix and stir the slag in the silo, thus improving the fluidity and uniformity of the slag; S42: According to the soft rock characteristics of the strata in the water-rich fault zone and the excavation requirements, engineering debris is added to the foaming agent for immersion tests, and the dispersion effect of foaming agents with different proportions on the mud cake is analyzed to obtain the best dispersant dilution multiple that meets the excavation control requirements.

7. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 4, characterized in that: In step S42, a calcium-magnesium ion resistant earth pressure balance shield foaming agent is used, and its formula is: 46.1% to 64.2% of a surfactant, 8.6% to 13.9% of a foam stabilizer, 6.7% to 9.8% of a thickener, 11.9% to 21.8% of a sodium phosphate buffer, 3.7% to 5.3% of a preservative, and the balance is water.

8. The method for rapid excavation of a TBM earth pressure balance dual-mode dual-shield tunnel boring machine in a water-rich fault zone stratum according to claim 1, characterized in that: Step S4 also includes sub-S43, selecting the air pressure auxiliary mode, using the air compressor to inject compressed air into the soil chamber to balance the excavation surface together with the slag in the chamber that is not yet full.

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