Construction method of shield tunneling machine tunneling type through subsurface excavation tunnel

Abstract

The invention relates to the field of underground excavation tunnels, in particular to a construction method of a shield tunneling machine tunneling type through underground excavation tunnel, which comprises the following steps: S1, site investigation: according to site boundary conditions, carrying out detailed investigation on an underground excavation crossing section to ensure construction safety; and S2, then underground excavation is conducted on the crossing section along the left line, and shield excavation is started from the first underground excavation starting point, the second underground excavation starting point, the third underground excavation starting point and the fourth underground excavation starting point. According to the method, a transverse channel is arranged, after the strength of backfill mortar meets the design requirement, a shield tunneling machine continues to conduct tunneling into a subsurface tunnel till the backfill mortar completely passes through the subsurface tunnel, then the shield tunneling machine enters a next shield interval for accumulated snow tunneling, and M5 mortar is backfilled in the whole section of the subsurface tunnel; after solidification, the strength can provide soil pressure during tunneling of a shield tunneling machine and counter force during segment assembly, meanwhile, due to the fact that filling is dense, collapse risks do not need to be worried about in the shield tunneling process, the working procedures of receiving, translation, secondary starting and the like of the shield in the subsurface tunnel are successfully skipped through the construction method, and the shield tunneling machine can safely pass through the subsurface tunnel.

Description

Technical Field

[0001] The invention belongs to the field of dark-cut tunnels, and in particular relates to a construction method for a dark-cut tunnel driven by a shield machine. Background Art

[0002] With the acceleration of urbanization, urban traffic pressure is increasing. As an important means to solve the problem of urban congestion, the construction scale of rail transit systems such as subways is constantly expanding. In the construction process of subway tunnels, the shield method has become one of the main construction methods due to its advantages such as high efficiency, safety, and little impact on ground traffic. However, in actual projects, it is often necessary to cross existing dark tunnels or areas with complex geological conditions, which poses a higher challenge to the excavation construction of shield machines. In the construction of subway tunnels, dark tunnels are usually used in local crack defense sections.

[0003] At present, the size of the vertical shaft for dark-excavated tunnel construction is usually small, which makes it very difficult to transport and install the bracket when the shield machine is received. At the same time, the shield machine is often not hoisted out after dismantling because the space is small and effective hoisting operations cannot be carried out. The inner diameter of the dark-excavated tunnel is close to the outer diameter of the shield machine, which makes the construction space for the shield machine to move horizontally extremely limited, increasing the construction risk, especially in small-radius curve sections, the translation of the shield machine becomes more difficult and even difficult to implement. When the shield machine is started again in the dark-excavated tunnel, due to space limitations, the conventional reaction force system cannot be installed, which will affect the normal operation of the shield machine and increase the difficulty and risk of construction.

[0004] Therefore, a shield machine-driven tunnel construction method is proposed, which can solve the problems of difficulty in transporting brackets and inability to use large machinery in traditional solutions, and the time-consuming translation of shield machines in traditional solutions. The shield machine-driven tunnel construction method has high construction efficiency and can also solve the problems of difficulty in translation of shield machines and high construction risks in traditional solutions. The shield machine-driven tunnel construction method is basically the same as normal tunneling, and has a high safety factor. Summary of the invention

[0005] In order to overcome the problem that the size of the vertical shaft for dark-excavated tunnel construction is usually small, the bracket transportation, installation and lifting out when receiving the shield machine are difficult, and the translation of the shield machine becomes more difficult. When the shield machine is started again in the dark-excavated tunnel, due to space limitations, a conventional reaction force system cannot be installed.

[0006] In order to solve the above technical problems, the present invention provides a shield machine excavation type through-dark excavation tunnel construction method, the steps of which are as follows:

[0007] S1: On-site survey: Conduct detailed survey of the dark excavation crossing section according to the on-site boundary conditions to ensure construction safety;

[0008] S2: Then, along the left line dark excavation crossing section, shield excavation starts from the first dark excavation starting point, the second dark excavation starting point, the third dark excavation starting point and the fourth dark excavation starting point;

[0009] S21: After excavation, continue to excavate grooves along the side walls of the channel, with the excavation depth less than ten centimeters, and build small mileage tunnel gate ring beams along the inside of the excavated grooves;

[0010] S22: Strengthen the small mileage door ring beam, install stainless steel columns on the side walls of the small mileage door ring beam, thread the ring sleeve on the stainless steel column, fix the support plate on the tunnel side wall with long screws, and then use a welding gun to quickly weld the ring sleeve and the support plate;

[0011] S3: Continue excavation and build a large mileage tunnel gate ring beam in the passage;

[0012] S31: repeat the steps of S21-S22 to reinforce the ring beam of the large mileage portal;

[0013] S4: Excavate a transverse passage between the ring beam of the large-mileage tunnel gate and the ring beam of the small-mileage tunnel gate;

[0014] S5: Install an arch support mechanism on the inner wall of the excavated tunnel, tie a steel cage on the arch support mechanism, and backfill mortar on the steel cage;

[0015] S51: pouring concrete sand and gravel mortar layers in the first dark excavation backfill section, the second dark excavation backfill section, the third dark excavation backfill section and the fourth dark excavation backfill section;

[0016] S52: shaping the poured concrete sand-gravel slurry layer by using a formwork method;

[0017] S6: After the backfill mortar strength meets the design requirements, the shield machine continues to excavate into the dark excavation tunnel until it completely passes through and then enters the next shield section for snow excavation. During the excavation process, the shield machine is kept stable to avoid accidents caused by changes in ground conditions. The shield machine excavates until it completely passes through the dark excavation tunnel section until the shield tail is out of the dark excavation backfill section;

[0018] S7: M5 mortar is backfilled across the entire section of the dark-excavated tunnel. After solidification, its strength can provide the soil pressure during shield excavation and the reaction force during segment assembly.

[0019] S8: excavate the right tunnel, the excavation steps are the same as S1-S7, and then test the strength of the backfill mortar;

[0020] S9: After the strength of the backfill mortar reaches the design requirements again and is fully tested and confirmed to be correct, the subsequent segment assembly work can be carried out. The segment assembly must be carried out strictly in accordance with the design drawings and technical specifications to ensure the installation accuracy and flatness of each ring of segments to ensure the overall stability and sealing of the tunnel structure;

[0021] S10: During the segment assembly process, grouting is carried out simultaneously. Cement slurry or other grouting materials are injected into the gaps between the segments and the soil through the grouting holes on the segments to fill the gaps, reduce ground settlement, and further enhance the bearing capacity and stability of the tunnel structure.

[0022] S11: With the continuous excavation of the shield machine and the continuous assembly of the segments, it is necessary to regularly inspect and monitor the quality of the completed tunnel sections, including the deviation of the tunnel axis, the misalignment of the segments, leakage, etc., to ensure that the tunnel construction quality meets the design requirements. For any problems found, remedial measures should be taken in a timely manner;

[0023] S12: When the shield machine completely passes through the current shield section and enters the next shield section for excavation, the above steps (S6 to S11) should be repeated until the entire tunnel project is completed. During this process, special attention should be paid to the maintenance and care of the shield machine to ensure that it maintains a good working condition and excavation performance under long-term and continuous working conditions;

[0024] S13: After the tunnel is completed, it is necessary to carry out the installation and commissioning of the tunnel interior decoration, lighting, ventilation, drainage and other ancillary facilities, as well as the final acceptance and performance test of the tunnel structure to ensure that the tunnel can be put into use safely and smoothly;

[0025] S14: Finally, according to the monitoring data and actual conditions during the operation of the tunnel, timely maintenance and care work should be carried out to ensure the long-term stability and safety of the tunnel structure, including regular inspection of the operation status of the tunnel structure, drainage system, ventilation system and other facilities, timely repair of damaged parts, and taking corresponding preventive maintenance measures.

[0026] Furthermore, the horizontal curve of the shield tunnel crossing section is a 360-meter right-turn circular curve section, and the vertical curve is a downhill slope of 25.5‰.

[0027] Furthermore, the top view of the transverse passage is cross-shaped.

[0028] Furthermore, the ring beams of the large-mileage tunnel portal and the small-mileage tunnel portal are both assembled after being cast with high-strength reinforced concrete.

[0029] Furthermore, an upper step dark excavation backfill section and a lower step dark excavation backfill section are set at the end point of the left line, and the level elevation of the upper step dark excavation backfill section is greater than the level elevation of the lower step dark excavation backfill section.

[0030] Furthermore, the slope between the upper step dark excavation backfill section and the lower step dark excavation backfill section is less than thirty degrees.

[0031] Furthermore, the transverse length of the transverse passage is less than three hundred meters, and the bottom of the transverse passage is cast with a reinforced concrete base, the thickness of the base being greater than half a meter.

[0032] Furthermore, the arcs of the left and right line excavations are both less than thirty degrees.

[0033] Furthermore, the center of the transverse passage is a frame-shaped well body, and the frame-shaped well body extends upward to above the ground.

[0034] Beneficial effects of the present invention:

[0035] 1. By setting up a cross channel, after the strength of the backfill mortar meets the design requirements, the shield machine continues to excavate into the dark tunnel until it passes through completely and then enters the next shield section for snow excavation. The entire section of the dark tunnel is backfilled with M5 mortar. After solidification, its strength can provide the soil pressure during shield excavation and the reaction force during segment assembly. At the same time, due to the dense filling, there is no need to worry about the risk of collapse during shield excavation;

[0036] 2. By adopting the above-mentioned construction method, the shield machine can successfully skip the processes of receiving, moving, and starting again in the dark tunnel, and the shield machine can safely pass through the dark tunnel;

[0037] 3. Compared with the traditional dark excavation construction method, shield tunneling through dark excavation tunnels can save construction time. The shield direct excavation method can reduce 2 times of bracket transportation and installation, 1 time of machine dismantling, 1 time of machine installation and commissioning, 1 time of reaction system installation and 1 time of shield machine translation and supporting equipment compared with the traditional construction method, thus reducing the loss of manpower and material resources;

[0038] 4. Safe and reliable: Traditional construction methods face the situation of narrow working space, difficult turning and easy injury to personnel when constructing in dark excavated tunnels with small radius curves. The shield method is a complete and mature process, which is safe and reliable and can be easily constructed in small radius curves. Under the premise of ensuring safety and quality, it has achieved faster construction efficiency and provided experience accumulation for similar engineering construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of each construction area in the shield machine excavation type dark excavation tunnel construction method provided by the present invention;

[0040] Figure 2 A schematic diagram of full-section backfilling in a dark-cut tunnel in the shield machine-driven dark-cut tunnel construction method provided by the present invention. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0042] Embodiment 1

[0043] This specific implementation method is a shield machine excavation type through dark excavation tunnel construction method, the steps are as follows:

[0044] S1: On-site survey: Conduct detailed survey of the dark excavation crossing section according to the on-site boundary conditions to ensure construction safety;

[0045] S2: Then, along the left line dark excavation crossing section, shield excavation starts from the first dark excavation starting point, the second dark excavation starting point, the third dark excavation starting point and the fourth dark excavation starting point;

[0046] S21: After excavation, continue to excavate grooves along the side walls of the channel, with the excavation depth less than ten centimeters, and build small mileage tunnel gate ring beams along the inside of the excavated grooves;

[0047] S22: Strengthen the small mileage door ring beam, install stainless steel columns on the side walls of the small mileage door ring beam, thread the ring sleeve on the stainless steel column, fix the support plate on the tunnel side wall with long screws, and then use a welding gun to quickly weld the ring sleeve and the support plate;

[0048] S3: Continue excavation and build a large mileage tunnel gate ring beam in the passage;

[0049] S31: repeat the steps of S21-S22 to reinforce the ring beam of the large mileage portal;

[0050] S4: Excavate a transverse passage between the ring beam of the large-mileage tunnel gate and the ring beam of the small-mileage tunnel gate;

[0051] S5: Install an arch support mechanism on the inner wall of the excavated tunnel, tie a steel cage on the arch support mechanism, and backfill mortar on the steel cage;

[0052] S51: pouring concrete sand and gravel mortar layers in the first dark excavation backfill section, the second dark excavation backfill section, the third dark excavation backfill section and the fourth dark excavation backfill section;

[0053] S52: shaping the poured concrete sand-gravel slurry layer by using a formwork method;

[0054] S6: After the backfill mortar strength meets the design requirements, the shield machine continues to excavate into the dark excavation tunnel until it completely passes through and then enters the next shield section for snow excavation. During the excavation process, the shield machine is kept stable to avoid accidents caused by changes in ground conditions. The shield machine excavates until it completely passes through the dark excavation tunnel section until the shield tail is out of the dark excavation backfill section;

[0055] S7: M5 mortar is backfilled across the entire section of the dark-excavated tunnel. After solidification, its strength can provide the soil pressure during shield excavation and the reaction force during segment assembly.

[0056] S8: excavate the right tunnel, the excavation steps are the same as S1-S7, and then test the strength of the backfill mortar;

[0057] S9: After the strength of the backfill mortar reaches the design requirements again and is fully tested and confirmed to be correct, the subsequent segment assembly work can be carried out. The segment assembly must be carried out strictly in accordance with the design drawings and technical specifications to ensure the installation accuracy and flatness of each ring of segments to ensure the overall stability and sealing of the tunnel structure;

[0058] S10: During the segment assembly process, grouting is carried out simultaneously. Cement slurry or other grouting materials are injected into the gaps between the segments and the soil through the grouting holes on the segments to fill the gaps, reduce ground settlement, and further enhance the bearing capacity and stability of the tunnel structure.

[0059] S11: With the continuous excavation of the shield machine and the continuous assembly of the segments, it is necessary to regularly inspect and monitor the quality of the completed tunnel sections, including the deviation of the tunnel axis, the misalignment of the segments, leakage, etc., to ensure that the tunnel construction quality meets the design requirements. For any problems found, remedial measures should be taken in a timely manner;

[0060] S12: When the shield machine completely passes through the current shield section and enters the next shield section for excavation, the above steps (S6 to S11) should be repeated until the entire tunnel project is completed. During this process, special attention should be paid to the maintenance and care of the shield machine to ensure that it maintains a good working condition and excavation performance under long-term and continuous working conditions;

[0061] S13: After the tunnel is completed, it is necessary to carry out the installation and commissioning of the tunnel interior decoration, lighting, ventilation, drainage and other ancillary facilities, as well as the final acceptance and performance test of the tunnel structure to ensure that the tunnel can be put into use safely and smoothly;

[0062] S14: Finally, according to the monitoring data and actual conditions during the operation of the tunnel, timely maintenance and care work should be carried out to ensure the long-term stability and safety of the tunnel structure, including regular inspection of the operation status of the tunnel structure, drainage system, ventilation system and other facilities, timely repair of damaged parts, and taking corresponding preventive maintenance measures.

[0063] Furthermore, the horizontal curve of the shield tunnel crossing section is a 360-meter right-turn circular curve section, and the vertical curve is a downhill slope of 25.5‰.

[0064] Furthermore, the top view of the transverse passage is cross-shaped.

[0065] Furthermore, the ring beams of the large-mileage tunnel portal and the small-mileage tunnel portal are both assembled after being cast with high-strength reinforced concrete.

[0066] Furthermore, an upper step dark excavation backfill section and a lower step dark excavation backfill section are set at the end point of the left line, and the level elevation of the upper step dark excavation backfill section is greater than the level elevation of the lower step dark excavation backfill section.

[0067] Furthermore, the slope between the upper step dark excavation backfill section and the lower step dark excavation backfill section is less than thirty degrees.

[0068] Furthermore, the transverse length of the transverse passage is less than three hundred meters, and the bottom of the transverse passage is cast with a reinforced concrete base, the thickness of the base being greater than half a meter.

[0069] Furthermore, the arcs of the left and right line excavations are both less than thirty degrees.

[0070] Furthermore, the center of the transverse passage is a frame-shaped well body, and the frame-shaped well body extends upward to above the ground.

[0071] When using the construction method of this technical solution, the steps are as follows:

[0072] S1: On-site survey: Conduct detailed survey of the dark excavation crossing section according to the on-site boundary conditions to ensure construction safety;

[0073] S2: Then, along the left line dark excavation crossing section, shield excavation starts from the first dark excavation starting point, the second dark excavation starting point, the third dark excavation starting point and the fourth dark excavation starting point;

[0074] S21: After excavation, continue to excavate grooves along the side walls of the channel, with the excavation depth less than ten centimeters, and build small mileage tunnel gate ring beams along the inside of the excavated grooves;

[0075] S22: Strengthen the small mileage door ring beam, install stainless steel columns on the side walls of the small mileage door ring beam, thread the ring sleeve on the stainless steel column, fix the support plate on the tunnel side wall with long screws, and then use a welding gun to quickly weld the ring sleeve and the support plate;

[0076] S3: Continue excavation and build a large mileage tunnel gate ring beam in the passage;

[0077] S31: repeat the steps of S21-S22 to reinforce the ring beam of the large mileage portal;

[0078] S4: Excavate a transverse passage between the ring beam of the large-mileage tunnel gate and the ring beam of the small-mileage tunnel gate;

[0079] S5: Install an arch support mechanism on the inner wall of the excavated tunnel, tie a steel cage on the arch support mechanism, and backfill mortar on the steel cage;

[0080] S51: pouring concrete sand and gravel mortar layers in the first dark excavation backfill section, the second dark excavation backfill section, the third dark excavation backfill section and the fourth dark excavation backfill section;

[0081] S52: shaping the poured concrete sand-gravel slurry layer by using a formwork method;

[0082] S6: After the backfill mortar strength meets the design requirements, the shield machine continues to excavate into the dark excavation tunnel until it completely passes through and then enters the next shield section for snow excavation. During the excavation process, the shield machine is kept stable to avoid accidents caused by changes in ground conditions. The shield machine excavates until it completely passes through the dark excavation tunnel section until the shield tail is out of the dark excavation backfill section;

[0083] S7: M5 mortar is backfilled across the entire section of the dark-excavated tunnel. After solidification, its strength can provide the soil pressure during shield excavation and the reaction force during segment assembly.

[0084] S8: excavate the right tunnel, the excavation steps are the same as S1-S7, and then test the strength of the backfill mortar;

[0085] S9: After the strength of the backfill mortar reaches the design requirements again and is fully tested and confirmed to be correct, the subsequent segment assembly work can be carried out. The segment assembly must be carried out strictly in accordance with the design drawings and technical specifications to ensure the installation accuracy and flatness of each ring of segments to ensure the overall stability and sealing of the tunnel structure;

[0086] S10: During the segment assembly process, grouting is carried out simultaneously. Cement slurry or other grouting materials are injected into the gaps between the segments and the soil through the grouting holes on the segments to fill the gaps, reduce ground settlement, and further enhance the bearing capacity and stability of the tunnel structure.

[0087] S11: With the continuous excavation of the shield machine and the continuous assembly of the segments, it is necessary to regularly inspect and monitor the quality of the completed tunnel sections, including the deviation of the tunnel axis, the misalignment of the segments, leakage, etc., to ensure that the tunnel construction quality meets the design requirements. For any problems found, remedial measures should be taken in a timely manner;

[0088] S12: When the shield machine completely passes through the current shield section and enters the next shield section for excavation, the above steps (S6 to S11) should be repeated until the entire tunnel project is completed. During this process, special attention should be paid to the maintenance and care of the shield machine to ensure that it maintains a good working condition and excavation performance under long-term and continuous working conditions;

[0089] S13: After the tunnel is completed, it is necessary to carry out the installation and commissioning of the tunnel interior decoration, lighting, ventilation, drainage and other ancillary facilities, as well as the final acceptance and performance test of the tunnel structure to ensure that the tunnel can be put into use safely and smoothly;

[0090] S14: Finally, according to the monitoring data and actual conditions during the operation of the tunnel, timely maintenance and care work should be carried out to ensure the long-term stability and safety of the tunnel structure, including regular inspection of the operation status of the tunnel structure, drainage system, ventilation system and other facilities, timely repair of damaged parts, and taking corresponding preventive maintenance measures.

[0091] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. A shield machine tunneling method for tunnel construction, characterized in that: The steps are as follows: S1: On-site survey: Conduct detailed survey of the dark excavation crossing section according to the on-site boundary conditions to ensure construction safety; S2: Then, along the left line dark excavation crossing section, shield excavation starts from the first dark excavation starting point, the second dark excavation starting point, the third dark excavation starting point and the fourth dark excavation starting point; S21: After excavation, continue to excavate grooves along the side walls of the channel, with the excavation depth less than ten centimeters, and build small mileage tunnel gate ring beams along the inside of the excavated grooves; S22: Strengthen the small mileage door ring beam, install stainless steel columns on the side walls of the small mileage door ring beam, thread the ring sleeve on the stainless steel column, fix the support plate on the tunnel side wall with long screws, and then use a welding gun to quickly weld the ring sleeve and the support plate; S3: Continue excavation and build a large mileage tunnel gate ring beam in the passage; S31: repeat the steps of S21-S22 to reinforce the ring beam of the large mileage portal; S4: Excavate a transverse passage between the ring beam of the large-mileage tunnel gate and the ring beam of the small-mileage tunnel gate; S5: Install an arch support mechanism on the inner wall of the excavated tunnel, tie a steel cage on the arch support mechanism, and backfill mortar on the steel cage; S51: pouring concrete sand and gravel mortar layers in the first dark excavation backfill section, the second dark excavation backfill section, the third dark excavation backfill section and the fourth dark excavation backfill section; S52: shaping the poured concrete sand-gravel slurry layer by using a formwork method; S6: After the backfill mortar strength meets the design requirements, the shield machine continues to excavate into the dark excavation tunnel until it completely passes through and then enters the next shield section for snow excavation. During the excavation process, the shield machine is kept stable to avoid accidents caused by changes in ground conditions. The shield machine excavates until it completely passes through the dark excavation tunnel section until the shield tail is out of the dark excavation backfill section; S7: M5 mortar is backfilled across the entire section of the dark-excavated tunnel. After solidification, its strength can provide the soil pressure during shield excavation and the reaction force during segment assembly. S8: excavate the right tunnel, the excavation steps are the same as S1-S7, and then test the strength of the backfill mortar; S9: After the strength of the backfill mortar reaches the design requirements again and is fully tested and confirmed to be correct, the subsequent segment assembly work can be carried out. The segment assembly must be carried out strictly in accordance with the design drawings and technical specifications to ensure the installation accuracy and flatness of each ring of segments to ensure the overall stability and sealing of the tunnel structure; S10: During the segment assembly process, grouting is carried out simultaneously. Cement slurry or other grouting materials are injected into the gaps between the segments and the soil through the grouting holes on the segments to fill the gaps, reduce ground settlement, and further enhance the bearing capacity and stability of the tunnel structure. S11: With the continuous excavation of the shield machine and the continuous assembly of the segments, it is necessary to regularly inspect and monitor the quality of the completed tunnel sections, including the deviation of the tunnel axis, the misalignment of the segments, leakage, etc., to ensure that the tunnel construction quality meets the design requirements. For any problems found, remedial measures should be taken in a timely manner; S12: When the shield machine completely passes through the current shield section and enters the next shield section for excavation, the above steps (S6 to S11) should be repeated until the entire tunnel project is completed. During this process, special attention should be paid to the maintenance and care of the shield machine to ensure that it maintains a good working condition and excavation performance under long-term and continuous working conditions; S13: After the tunnel is completed, it is necessary to carry out the installation and commissioning of the tunnel interior decoration, lighting, ventilation, drainage and other ancillary facilities, as well as the final acceptance and performance test of the tunnel structure to ensure that the tunnel can be put into use safely and smoothly; S14: Finally, according to the monitoring data and actual conditions during the operation of the tunnel, timely maintenance and care work should be carried out to ensure the long-term stability and safety of the tunnel structure, including regular inspection of the operation status of the tunnel structure, drainage system, ventilation system and other facilities, timely repair of damaged parts, and taking corresponding preventive maintenance measures.

2. The shield machine driven tunnel construction method according to claim 1, characterized in that: The horizontal curve of the shield tunneling section is a 360-meter right-turn circular curve section, and the vertical curve is a downhill slope of 25.5‰.

3. The shield machine tunneling method according to claim 1 is characterized in that: The top view of the cross passage is cross-shaped.

4. The shield machine driven tunnel construction method according to claim 1, characterized in that: The ring beams of large-mileage tunnel portals and small-mileage tunnel portals are both assembled after being cast with high-strength reinforced concrete.

5. The shield machine driven tunnel construction method according to claim 1, characterized in that: The upper step dark excavation backfill section and the lower step dark excavation backfill section are set at the end point of the left line. The level elevation of the upper step dark excavation backfill section is greater than the level elevation of the lower step dark excavation backfill section.

6. The shield machine driven tunnel construction method according to claim 5, characterized in that: The slope between the upper step dark excavation backfill section and the lower step dark excavation backfill section is less than thirty degrees.

7. The shield machine driven tunnel construction method according to claim 1, characterized in that: The horizontal length of the cross passage is less than three hundred meters, and the bottom of the cross passage is cast with reinforced concrete, and the thickness of the base is more than half a meter.

8. The shield machine driven tunnel construction method according to claim 1, characterized in that: The arcs of the left and right line excavations are both less than thirty degrees.

9. The shield machine driven tunnel construction method according to claim 1, characterized in that: The center of the transverse passage is a frame-shaped well body, which extends upward to above the ground.

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