Construction method for starting tunneling through single-side stress of TBM (Tunnel Boring Machine) at roadway intersection point

Abstract

The invention discloses a construction method of a TBM (Tunnel Boring Machine) for single-side stress starting tunneling at a roadway intersection point. The problem that the single side of a supporting shoe of the TBM is in the air is solved by pouring a concrete stress wall. The invention provides a construction method of TBM (tunnel boring machine) starting tunneling under single-side stress at a roadway intersection point. The construction method comprises the following steps: tunneling construction of a main roadway TBM, retreating of the TBM to a position behind an opening of a crossed roadway and arrangement of a protective wall, paying off at the position of the opening of the crossed roadway, finishing of a starting working face of the crossed roadway by a drilling and blasting method, pouring of a supporting shoe stress wall, TBM propelling starting and dismantling of the supporting shoe stress wall. The construction efficiency of the TBM hard rock heading machine in the starting process of the crossing point of the mine development project is improved, the safety of TBM crossing point starting tunneling construction is guaranteed, manpower and material resources are saved, the working efficiency is improved, the safety of construction workers is guaranteed, and the method is suitable for being widely popularized in TBM mine development project crossing point starting tunneling construction operation.

Description

Technical Field

[0001] The present invention relates to the technical field of underground engineering construction, and in particular to a construction method for a TBM to excavate and advance at a tunnel intersection under single-side force. Background Art

[0002] In traditional underground mining construction, the drill-and-blast method has been gradually replaced by mechanized and intelligent TBM hard rock excavation technology due to high safety risks and low efficiency. TBMs offer advantages such as safety, efficiency, and high-quality construction. However, in the complex environment of underground mines, especially when constructing cross-tunnels, the TBM support shoe has nowhere to bear force on one side, making initial excavation and advancement difficult. Traditional solutions use steel pipe support devices, which have the following drawbacks: cumbersome operation, requiring frequent adjustments to the support device; unstable support force, which can easily cause surrounding rock collapse or flying rocks to injure people; auxiliary personnel need to frequently enter high-risk areas, posing a significant safety hazard; low construction efficiency, and high consumption of manpower and material resources. Summary of the Invention

[0003] The object of the present invention is to solve one of the above-mentioned technical problems at least to a certain extent.

[0004] To this end, the purpose of the present invention is to propose a construction method for TBM to start excavation at the intersection of tunnels with unilateral force, solve the problem of unilateral overhead force by casting support shoe load walls, and significantly improve construction efficiency and safety.

[0005] To achieve the above-mentioned object, one embodiment of the present invention provides a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force, comprising the following steps:

[0006] Step S1, TBM excavation construction of the main tunnel;

[0007] Step S2: The TBM retreats to the rear of the intersection tunnel opening and sets up a protective wall;

[0008] Step S3, laying out the intersection tunnel opening position;

[0009] Step S4, repairing the starting working face of the intersection tunnel by drilling and blasting method;

[0010] Step S5, pouring the support shoe bearing wall;

[0011] Step S6, TBM propulsion starts;

[0012] Step S7: removing the support shoe bearing wall.

[0013] According to one embodiment of the present invention, the main tunnel TBM excavation construction includes:

[0014] Step S11: Use a TBM hard rock tunnel boring machine to excavate and support the main tunnel according to the design requirements. After the excavation and support are completed, it is necessary to ensure that there are safe passages in both the cutter head and the tail of the TBM equipment to facilitate the entry and exit of personnel, equipment, and materials.

[0015] According to one embodiment of the present invention, the step of retreating the TBM to the rear of the intersection tunnel opening and setting up a protective wall includes:

[0016] Step S22: After the excavation and support of the TBM main tunnel are completed, the TBM equipment is retreated to 20 meters behind the opening of the cross tunnel using the TBM's own support shoe changing device, and a stone splash-proof retaining wall is built in front of the machine head using logs.

[0017] According to one embodiment of the present invention, the setting out of the intersection tunnel opening position includes:

[0018] In step S33, after the TBM equipment retreats to the designated position, the surveyor can accurately lay out the opening position of the cross tunnel, and the opening and the center line need to be marked to ensure the accuracy of the opening.

[0019] According to one embodiment of the present invention, the drilling and blasting method for repairing the starting working face of the cross-tunnel includes:

[0020] Step S44: trim the side walls of the intersection tunnel opening according to the intersection tunnel opening position placed by the surveyor. After the trimming is completed, it is necessary to ensure that when the TBM hard rock tunneling equipment advances to the intersection working face, the working face is basically parallel to the cutterhead.

[0021] According to one embodiment of the present invention, the casting of the support shoe bearing wall includes:

[0022] In step S55, according to the tunnel design drawing, the TBM hard rock tunnel boring machine is pushed to the finished cross tunnel working face. Using the equipment shield as the inner formwork, the support shoe cylinder is extended to half its support length, and then the shield body and cutterhead are covered with tarpaulin; the outer formwork is supported by large templates and square timbers, and the wall thickness is 500mm. Whether to add steel bars in the load-bearing wall is determined based on the actual situation on site; C30 concrete is used for pouring to form a TBM starting chamber with uniform force and standard shape to ensure that the support shoes are evenly stressed when the TBM advances forward.

[0023] According to one embodiment of the present invention, the TBM propulsion initiation includes:

[0024] Step S66: After the construction of the gripper bearing wall is completed, the TBM hard rock tunnel boring machine shield can be located in a starting chamber with uniform force on all sides and standard external contours. Because the shield and cutterhead have been covered with tarpaulin before pouring, and the gripper cylinder has been extended to half of its support length, after the pouring is completed, it can be ensured that the gripper has sufficient friction to support the TBM forward when the TBM starts to advance. The gripper can be retracted inward to ensure normal step change of the TBM.

[0025] According to one embodiment of the present invention, when the TBM starts to propel, the friction coefficient between the gripper shoe and the load-bearing wall is not less than 0.6.

[0026] According to one embodiment of the present invention, removing the gripper bearing wall includes:

[0027] Step S77: When the TBM starts successfully and the whole TBM machine has completely advanced into the interior of the cross tunnel, the support shoe bearing wall can be demolished by drilling and blasting or by excavator hammer according to the project needs to restore the original design of the tunnel.

[0028] According to one embodiment of the present invention, the construction method is applicable to TBM initial excavation construction of various types of cross tunnels in underground development projects of metal mines.

[0029] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention.

[0030] Compared with the prior art, the beneficial effects of the embodiments of the present application are:

[0031] The present invention provides a construction method for TBM to start excavation at a tunnel intersection with single-side force. The method combines the flexibility of traditional drilling and blasting construction with the high efficiency of TBM hard rock tunnel boring machines, improves the construction efficiency of TBM hard rock tunnel boring machines in the process of starting excavation at the intersection of mine development projects, and can ensure the safety of TBM excavation construction at the intersection. It saves manpower and material resources, improves work efficiency and ensures the safety of construction workers. The method is suitable for wide promotion in the excavation construction work at the intersection of TBM mine development projects.

[0032] The present invention provides a construction method for TBM to start excavation at a tunnel intersection under single-side force, which can greatly save manpower and material resources, improve the construction efficiency of TBM starting excavation at the intersection of mine development projects, and better ensure the personal safety of construction workers.

[0033] The present invention provides a construction method for TBM to start excavation at a tunnel intersection with single-side force, which effectively reduces the frequency of construction personnel approaching the TBM equipment head during TBM operation, reduces the consumption of manpower and material resources, and greatly improves the construction efficiency of TBM in starting excavation at a mine development intersection.

[0034] The present invention provides a construction method for TBM excavation at a tunnel intersection with single-side load. The method uses concrete cast support shoe load-bearing walls to replace the manual frequent replacement and installation of steel pipe support devices, which not only saves labor consumption but also ensures construction safety.

[0035] The present invention provides a construction method for a TBM to start excavation at a tunnel intersection under unilateral force, thereby forming a starting chamber with a regular shape, ensuring that the force on the support shoe of the TBM is more uniform when the TBM starts excavation, and preventing the starting direction from deviating from the design.

[0036] The present invention provides a construction method for TBM excavation at a tunnel intersection with single-side force. The construction method is simple and the required materials can be obtained from a wide range of sources. The construction method is suitable for wide promotion in the construction of TBM excavation at the intersection of various mine tunnels and engineering tunnels.

[0037] To better understand the technical means of the present invention and to facilitate implementation in accordance with the description, and to make the above-mentioned and other purposes, features, and advantages of the present invention more readily apparent, preferred embodiments are described below in detail with reference to the accompanying drawings. Other features and advantages of the present invention will be explained in the subsequent description and, in part, will become apparent from the description or be demonstrated through the practice of the present invention. The purposes and other advantages of the present invention may be achieved and attained through the structures particularly noted in the description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 This is a flow chart of a construction method for a TBM to initiate excavation at a roadway intersection under single-side force according to one embodiment of the present invention;

[0040] Figure 2 This is another flow chart of a construction method for a TBM to excavate and advance at a roadway intersection under unilateral force provided in accordance with one embodiment of the present invention;

[0041] Figure 3 1. It is a structural schematic diagram of a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force provided by one embodiment of the present invention;

[0042] Figure 4 This is another structural schematic diagram of a construction method for a TBM to initiate excavation at a tunnel intersection under unilateral force provided by one embodiment of the present invention;

[0043] Figure 5 Schematic diagram of a TBM cutterhead for construction at a roadway intersection according to a construction method for initiating excavation at a roadway intersection under unilateral force provided by one embodiment of the present invention;

[0044] Figure 6 This is a schematic diagram of the traditional TBM excavation construction method at a fork point. DETAILED DESCRIPTION

[0045] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0046] Traditional drilling and blasting methods in underground metal mine construction present high safety risks and low efficiency. To address these challenges, my country's mining equipment is gradually evolving towards mechanization, modernization, and intelligentization. In recent years, TBM (Thrust Block Machine) hard rock excavation technology has been gradually introduced into metal mine construction. With the continuous advancement of mine development technology, TBM (Tunnel Boring Machine) hard rock excavation equipment, as a new type of tunnel and roadway excavation equipment, offers advantages such as safety, efficiency, and high-quality cross-section formation, and is gradually being adopted in various tunnel and underground mine construction applications. However, underground mine development differs from conventional tunnel construction due to its complex development design, with a crisscrossing network of various transport lanes, through-vein lanes, and countermeasure lanes. The flexibility of TBM hard rock excavation equipment in such conditions lags significantly compared to conventional drilling and blasting methods. This is because after a TBM excavates a roadway, attempting to construct another intersecting roadway in the middle of the existing roadway presents a problem where the TBM gripper has no support on one side, preventing the TBM from successfully initiating excavation.

[0047] The present invention proposes a construction method for TBM to start excavation at a tunnel intersection with single-side force. The method is suitable for the construction of TBM to start excavation at the intersection opening during the construction of various types of intersection tunnels. The construction method can effectively solve the problem of difficulty in starting when the TBM is in a single-side suspended state during the construction of the intersection tunnel, and greatly saves manpower and material resources, reduces the construction time of TBM tunnel intersection excavation, and better ensures the safety of TBM excavation construction auxiliary personnel. The method is suitable for wide promotion in the construction of TBM excavation at the intersection of various types of mine tunnels and engineering tunnels.

[0048] Specifically, a construction method for a TBM to excavate and advance at a tunnel intersection under single-side force according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0049] Figure 1This is a flow chart of a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force, provided according to one embodiment of the present invention. Figure 2 This is another flow chart of a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force provided by one embodiment of the present invention. Figure 3 1 is a schematic diagram of a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force provided by an embodiment of the present invention. Figure 4 FIG2 is another structural diagram of a construction method for a TBM to excavate and advance at a tunnel intersection under unilateral force provided by an embodiment of the present invention. Figure 5 The diagram is a schematic diagram of a TBM cutterhead for construction according to an embodiment of the present invention, wherein a TBM is subjected to unilateral force to initiate excavation at a tunnel intersection.

[0050] Please refer to Figure 1-Figure 5 This embodiment provides a construction method for a TBM to excavate and advance at a roadway intersection under unilateral force, which includes the following steps:

[0051] Step S1, TBM excavation construction of the main tunnel;

[0052] The main tunnel TBM excavation construction includes:

[0053] Step S11: Use a TBM hard rock tunnel boring machine to excavate and support the main tunnel according to the design requirements. After the excavation and support are completed, it is necessary to ensure that there are safe passages in both the cutter head and the tail of the TBM equipment to facilitate the entry and exit of personnel, equipment, and materials.

[0054] Step S2: The TBM retreats to the rear of the intersection tunnel opening and sets up a protective wall;

[0055] The TBM retreat to the rear of the intersection tunnel opening and the installation of a protective wall include:

[0056] In step S22, after the excavation and support of the TBM main tunnel are completed, the TBM equipment is retreated to 20 meters behind the opening of the cross tunnel using the TBM's own support shoe changing device, and a stone splash-proof retaining wall is built in front of the machine head using logs to prevent subsequent drilling and blasting operations from damaging the TBM equipment.

[0057] Step S3, laying out the intersection tunnel opening position;

[0058] The layout of the intersection tunnel opening position includes:

[0059] In step S33, after the TBM equipment retreats to the designated position, the surveyor can accurately lay out the opening position of the cross tunnel, and the opening and the center line need to be marked to ensure the accuracy of the opening.

[0060] Step S4, repairing the starting working face of the intersection tunnel by drilling and blasting method;

[0061] Among them, the drilling and blasting method for repairing the starting working face of the cross tunnel includes:

[0062] Step S44: trim the side walls of the intersection tunnel opening according to the intersection tunnel opening position placed by the surveyor. After the trimming is completed, it is necessary to ensure that when the TBM hard rock tunneling equipment advances to the intersection working face, the working face is basically parallel to the cutterhead.

[0063] Step S5, pouring the support shoe bearing wall;

[0064] Among them, the cast support shoe bearing wall includes:

[0065] In step S55, according to the tunnel design, the TBM is advanced to the finished cross-tunnel working face. Using the machine shield as the inner formwork, the gripper cylinders are extended to half their span. A tarp is then placed over the shield and cutterhead to prevent concrete from pouring into the machine and potentially damaging it. The outer formwork is supported by large templates and square timbers. The wall thickness is 500mm, and the addition of steel reinforcement within the load-bearing wall will be determined based on site conditions. C30 concrete is used for pouring, ensuring a uniform and properly shaped TBM launch chamber, ensuring even force on the grippers as the TBM advances.

[0066] Step S6, TBM propulsion starts;

[0067] Among them, TBM propulsion and launching include:

[0068] Step S66: After the construction of the gripper bearing wall is completed, the TBM hard rock tunnel boring machine shield can be located in a starting chamber with uniform force on all sides and standard external contours. Because the shield and cutterhead have been covered with tarpaulin before pouring, and the gripper cylinder has been extended to half of its support length, after the pouring is completed, it can be ensured that the gripper has sufficient friction to support the TBM forward when the TBM starts to advance. The gripper can be retracted inward to ensure normal step change of the TBM.

[0069] It should be noted that when the TBM starts to advance, the friction coefficient between the support shoe and the load-bearing wall is not less than 0.6.

[0070] Step S7, removing the support shoe bearing wall;

[0071] Among them, the demolition of the support shoe bearing wall includes:

[0072] Step S77: When the TBM starts successfully and the whole TBM machine has completely advanced into the interior of the cross tunnel, the support shoe bearing wall can be demolished by drilling and blasting or by excavator hammer according to the project needs to restore the original design of the tunnel.

[0073] The embodiment of the present invention provides a construction method for TBM to start excavation and advancement at a tunnel intersection with single-side force. It combines the flexibility of traditional drilling and blasting construction with the high efficiency of TBM hard rock tunnel boring machines, improves the construction efficiency of TBM hard rock tunnel boring machines in the process of starting excavation and advancement at the intersection of mine development projects, and ensures the safety of TBM excavation and advancement construction at the intersection. It saves manpower and material resources, improves work efficiency and ensures the safety of construction workers. It is suitable for wide promotion in the excavation and advancement construction work at the intersection of TBM mine development projects.

[0074] It should be noted that Figure 6 This is a diagram of the traditional TBM tunneling construction method at a fork point. Figure 6 The traditional TBM construction method of single-sided force excavation at the intersection of tunnels is as follows: When the TBM hard rock tunnel boring machine is constructing an intersection tunnel, the traditional construction method is: ① TBM excavation construction in the main tunnel, ② TBM retreat operation, ③ TBM installation of seamless steel pipe support device on the aerial side, ④ TBM eccentric load advancement, ⑤ repeating steps ③ and ④ every time the advancement is 20-30cm, ⑥ TBM head is excavated into the surrounding rock as a whole, and ⑦ TBM traditional excavation method. This traditional eccentric loading tunneling method is extremely cumbersome to operate, and the overhead support device needs to be adjusted frequently. In addition, the force of the support device is unstable, the support area is small, the support effect is poor, and auxiliary personnel are often required to go deep into the head position to adjust and install it. This operation mode consumes a lot of manpower and material resources and has extremely high safety risks. Because the surrounding rock of the tunnel at the head is generally in a bare tunnel that has just been excavated and has not been inspected or supported, there is a risk of spalling and roof collapse. The support device is squeezed by the support shoe and is in a high stress state with the tunnel wall for a long time. As the equipment moves forward, the support device will gradually tilt due to the friction between the equipment and the surrounding rock. If the support force between the equipment and the surrounding rock is too large and the surrounding rock is broken, the support force between the equipment and the surrounding rock can easily squeeze and crack the surrounding rock, causing flying rocks to injure people. Therefore, the traditional TBM eccentric loading tunneling method can no longer meet the requirements of modern mine safety construction. Therefore, there is an urgent need for a construction method that can ensure construction safety, speed up excavation efficiency, and reduce manpower and material consumption to solve the construction and safety problems of the above TBM intersections.

[0075] As can be seen from the above, there are many problems with traditional construction methods. To this end, the present invention provides a construction method for TBM excavation at a tunnel intersection with unilateral force. The construction method consists of seven parts: step S1, TBM excavation construction in the main tunnel; step S2, TBM retreating to the rear of the intersection tunnel opening and setting up a protective wall; step S3, laying out the position of the intersection tunnel opening; step S4, drilling and blasting to repair the starting working face of the intersection tunnel; step S5, casting the support shoe force wall; step S6, TBM advancing and starting; step S7, removing the support shoe force wall. The construction method that combines the traditional drilling and blasting method with the new TBM tunnel excavation construction method perfectly solves the problems of low construction efficiency of the traditional drilling and blasting method and high difficulty and danger of unilateral force excavation at the intersection of TBM tunnels.

[0076] Specifically, the construction method of the present invention is as follows: using a TBM hard rock tunnel boring machine to excavate and support the main tunnel according to the design requirements, and after the excavation and support are completed, it is necessary to ensure that there are safe passages leading to the surface in both the cutter head and the tail of the TBM equipment to facilitate the lowering of personnel, equipment, and materials; after the excavation of the main tunnel of the TBM is completed, the TBM equipment is retreated to 20 meters behind the opening of the cross tunnel using the TBM's own support shoe changing device, and a stone splash-proof retaining wall is made of logs in front of the machine head to prevent subsequent drilling and blasting operations from damaging the TBM equipment; After the equipment retreats to the designated position, the surveyor can accurately lay out the position of the intersection tunnel opening, and mark the center and waist lines of the opening to ensure the accuracy of the opening; according to the intersection tunnel opening position placed by the surveyor, the side walls of the intersection tunnel opening are trimmed. After the trimming is completed, it is necessary to ensure that when the TBM hard rock tunneling equipment is pushed to the intersection working face, the working face is basically parallel to the cutterhead; according to the tunnel design drawing, the TBM hard rock tunneling machine is pushed to the trimmed intersection tunnel working face, and the equipment shield is used as the inner template, and the support shoe cylinder is extended to half of its support distance. length, and then cover the shield and cutterhead with tarpaulin to prevent concrete from pouring into the equipment and damaging it. The outer formwork is supported by large templates and square timber, and the wall thickness is 500mm. Whether to add steel bars in the load-bearing wall is determined according to the actual situation on site. C30 concrete is used for pouring to form a TBM starting chamber with uniform force and standard shape, ensuring that the support shoe is evenly stressed when the TBM moves forward. After the construction of the support shoe load-bearing wall is completed, the TBM hard rock tunnel boring machine shield can be in a starting chamber with uniform force on all sides and standard outline. Because the shield and cutterhead have been covered with tarpaulin before pouring, and the support shoe cylinders have been extended to half the length of their support distance, after pouring is completed, the TBM support shoes are pushed outward to increase the pressure between the support shoes and the surrounding rock and the load-bearing wall, ensuring that the support shoes have sufficient friction to support the TBM forward when it starts to advance forward, and the support shoes are retracted inward to ensure normal step change of the TBM; when the TBM starts smoothly and the entire TBM machine is completely excavated into the interior of the cross tunnel, the support shoe load wall can be demolished by drilling and blasting or by excavator hammer according to project needs to restore the original design of the tunnel.

[0077] The beneficial effects of the construction method of the present invention in which a TBM is subjected to unilateral force and begins excavation at a tunnel intersection are as follows:

[0078] This construction method combines the flexibility of traditional drilling and blasting construction with the high efficiency of TBM hard rock tunnel boring machines, improving the construction efficiency of TBM hard rock tunnel boring machines in the starting process of intersection points in mine development projects, and ensuring the safety of TBM excavation construction at intersection points. It saves manpower and material resources, improves work efficiency and ensures the safety of construction workers. It is suitable for wide promotion in the excavation construction operations at the starting points of TBM mine development projects.

[0079] This construction method can greatly save manpower and material resources, improve the efficiency of excavation at the intersection of TBM mine development projects, and better ensure the personal safety of construction workers.

[0080] This construction method effectively reduces the frequency of construction workers approaching the TBM equipment head during TBM operations, reduces the consumption of manpower and material resources, and greatly improves the construction efficiency of TBM excavation and advancement construction at the intersection of mine development.

[0081] This construction method uses concrete cast support shoe load-bearing walls to replace the frequent manual replacement and installation of steel pipe support devices, which not only saves labor consumption but also ensures construction safety.

[0082] This construction method forms a starting chamber with a regular shape, ensuring that the support shoes are more evenly stressed when the TBM starts excavating and advancing, and is less likely to cause the starting direction to deviate from the design.

[0083] This construction method is simple and the required materials are widely available. It is suitable for widespread promotion in the initial excavation and construction of TBM intersections in various types of mine tunnels and engineering tunnels.

[0084] The above description is merely a preferred embodiment of the present invention and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of disclosure involved in the present invention is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also includes other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the above-mentioned disclosed concepts. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in the present invention.

[0085] In addition, although adopting specific order to describe each operation, this should not be interpreted as requiring these operations to be executed in the specific order shown or in sequential order.Under certain environment, multitasking and parallel processing may be advantageous.Similarly, although comprising some specific implementation details in the above discussion, these should not be interpreted as limiting the scope of the present invention.Some features described in the context of independent embodiment can also be implemented in single embodiment in combination.On the contrary, the various features described in the context of independent embodiment also can be implemented in multiple embodiments individually or in the mode of any suitable subcombination.

[0086] Although the subject matter has been described in language specific to structural features and / or methodological logical acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are merely example forms of implementing the claims.

[0087] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be encompassed by the scope of the pending claims.

Claims

1. A construction method for TBM excavation at a roadway intersection with unilateral force, characterized in that: The steps include: Step S1, TBM excavation construction of the main tunnel; Step S2: The TBM retreats to the rear of the intersection tunnel opening and sets up a protective wall; Step S3, laying out the intersection tunnel opening position; Step S4, repairing the starting working face of the intersection tunnel by drilling and blasting method; Step S5, pouring the support shoe bearing wall; Step S6, TBM propulsion starts; Step S7: removing the support shoe bearing wall.

2. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 1 is characterized in that: The main tunnel TBM excavation construction includes: Step S11: Use a TBM hard rock tunnel boring machine to excavate and support the main tunnel according to the design requirements. After the excavation and support are completed, it is necessary to ensure that there are safe passages in both the cutter head and the tail of the TBM equipment to facilitate the entry and exit of personnel, equipment, and materials.

3. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 2, characterized in that: The TBM retreats to the rear of the intersection tunnel opening and sets up a protective wall, including: Step S22: After the excavation and support of the TBM main tunnel are completed, the TBM equipment is retreated to 20 meters behind the opening of the cross tunnel using the TBM's own support shoe changing device, and a stone splash-proof retaining wall is built in front of the machine head using logs.

4. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 3 is characterized in that: The cross tunnel opening position setting out includes: In step S33, after the TBM equipment retreats to the designated position, the surveyor can accurately lay out the opening position of the cross tunnel, and the opening and the center line need to be marked to ensure the accuracy of the opening.

5. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 4 is characterized in that: The drilling and blasting method for repairing the starting working face of the cross tunnel includes: Step S44: trim the side walls of the intersection tunnel opening according to the intersection tunnel opening position placed by the surveyor. After the trimming is completed, it is necessary to ensure that when the TBM hard rock tunneling equipment advances to the intersection working face, the working face is basically parallel to the cutterhead.

6. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 5, characterized in that: The casting support shoe bearing wall comprises: In step S55, according to the tunnel design drawing, the TBM hard rock tunnel boring machine is pushed to the finished cross tunnel working face. Using the equipment shield as the inner formwork, the support shoe cylinder is extended to half its support length, and then the shield body and cutterhead are covered with tarpaulin; the outer formwork is supported by large templates and square timbers, and the wall thickness is 500mm. Whether to add steel bars in the load-bearing wall is determined based on the actual situation on site; C30 concrete is used for pouring to form a TBM starting chamber with uniform force and standard shape to ensure that the support shoes are evenly stressed when the TBM advances forward.

7. The construction method of TBM excavation at a tunnel intersection with single-side force according to claim 6, characterized in that: The TBM propulsion initiation includes: Step S66: After the construction of the gripper bearing wall is completed, the TBM hard rock tunnel boring machine shield can be located in a starting chamber with uniform force on all sides and standard external contours. Because the shield and cutterhead have been covered with tarpaulin before pouring, and the gripper cylinder has been extended to half of its support length, after the pouring is completed, it can be ensured that the gripper has sufficient friction to support the TBM forward when the TBM starts to advance. The gripper can be retracted inward to ensure normal step change of the TBM.

8. The construction method of TBM excavation at a tunnel intersection with unilateral force according to claim 7, characterized in that: When the TBM starts to advance, the friction coefficient between the support shoe and the load-bearing wall is not less than 0.

6.

9. The construction method of TBM excavation at a tunnel intersection with single-side force according to claim 7, characterized in that: The dismantling of the support shoe bearing wall comprises: Step S77: When the TBM starts successfully and the whole TBM machine has completely advanced into the interior of the cross tunnel, the support shoe bearing wall can be demolished by drilling and blasting or by excavator hammer according to the project needs to restore the original design of the tunnel.

10. The construction method of a TBM excavating at a roadway intersection under single-side force according to any one of claims 1 to 9, characterized in that: The construction method is applicable to TBM initial excavation and construction of various cross tunnels in underground development projects of metal mines.

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