Rapid construction method for excavation of subway stations in dark and dark areas in spring lake areas

Abstract

The invention provides a rapid construction method for excavation of subway stations in spring and lake areas, and relates to the technical field of construction methods.The rapid construction method comprises the following steps that when a main body structure is excavated in an open excavation construction mode, a temporary vertical shaft is excavated in an open excavation mode at a first set position, and a transverse channel is excavated from the temporary vertical shaft to one side of a buckling arch pilot tunnel area to be excavated; an arch buckling pilot tunnel is excavated in advance from the position, right facing the main body structure, of the transverse channel; and after construction of the main body structure is completed, the channel main body is excavated from the position, right facing the to-be-excavated area of the channel main body, of the main body structure, and the buckling arch pilot tunnel communicates with the channel main body to form a connecting channel. Based on the construction scheme, parallel construction of open excavation and underground excavation is achieved through an improved strategy of space dislocation and time superposition, the total construction period is effectively shortened, and the construction efficiency is improved.

Description

Technical Field

[0001] This invention generally relates to the field of construction method technology, and specifically to a rapid construction method for open-cut and cut-and-cover subway stations in the Quanhu area. Background Technology

[0002] With the accelerating pace of urbanization, urban rail transit systems have gradually become an important pillar of urban public transportation systems. However, the construction of subway stations in complex urban environments faces significant technical challenges, especially in special areas like the Quanhu area with multiple geographical constraints.

[0003] While traditional open-cut methods offer advantages such as mature construction techniques and good structural integrity, their inherent limitations, including long construction cycles and the need for a large working area, make them unsuitable for the high-intensity development of urban core areas and the protection requirements of historical districts. Given the unique geological and hydrological conditions and complex construction environment of the Quanhu area, while simple tunneling can effectively avoid surface disturbances, it is prone to water and mud inrushes, incurring high support costs, and significantly increasing potential risks.

[0004] Therefore, to address the challenge of rapid construction of subway stations in the Quanhu area due to geographical constraints, existing technologies employ a combination of open-cut and tunneling methods. Specifically, open-cut excavation is used to create a pit at the designated depth; then, tunneling is carried out laterally along the sidewalls of this pit. This construction method still follows the sequence of open-cut followed by tunneling, and does not fundamentally solve the problem of long construction cycles associated with open-cut methods; it only provides a limited reduction in the overall construction period. Summary of the Invention

[0005] In view of the above-mentioned defects or deficiencies in the existing technology, it is desirable to provide a rapid construction method for open-cut and cut-and-cover subway stations in the Quanhu area.

[0006] This invention provides a rapid construction method for a subway station in the Quanhu area using both open-cut and cut-and-cover methods. The underground structure of the subway station includes: an interconnected main structure and two connecting passages; the two connecting passages are symmetrically arranged on both sides of the main structure, and the axis of the connecting passages extends along a first horizontal direction; the first horizontal direction is the direction of travel of the subway train; the connecting passage includes: an interconnected arched guide tunnel and a passage body; the arched guide tunnel is located directly above the passage body. The method includes: The main structure is excavated vertically using an open-cut method until the first target depth is reached; during the excavation of the main structure, steps Q1 to Q3 are performed simultaneously. Q1: Using open-cut construction, a temporary shaft is excavated vertically at a first predetermined position offset from the main structure along the second horizontal direction; the second horizontal direction is perpendicular to the first horizontal direction. Q2: Using the cut-and-cover method, excavate a transverse passage along the second horizontal direction at the second target depth inside the temporary shaft; the second target depth is the design boundary elevation between the arched guide tunnel and the main body of the passage. Q3: At the position where the transverse passage is directly opposite the main structure, construct the arched guide hole along the first horizontal direction; The main body of the tunnel is excavated using a cut-and-cover method; the arched guide tunnel and the main body of the tunnel form the connecting passage.

[0007] According to the technical solution provided by the present invention, Q1: A temporary shaft is excavated vertically at a first predetermined position offset from the main structure along a second horizontal direction using an open-cut construction method, comprising: Q1-1: Construct a second underground continuous wall and a second water-stop curtain with a second target depth at the first designated location; Q1-2: Using open-cut construction, excavate vertically at the first designated location until the second target depth is reached to obtain an initial temporary shaft; Q1-3: Construct the first sump and the first recharge well within the initial temporary shaft to obtain the temporary shaft.

[0008] According to the technical solution provided by the present invention, Q2: Using a cut-and-cover construction method, a transverse channel is excavated at the second target depth along the second horizontal direction within the inner wall of the temporary shaft, including: Q2-1: At the second target depth of the inner wall of the temporary shaft, a horizontal channel grouting reinforcement layer is constructed along the second horizontal direction on the side close to the main structure; the horizontal channel grouting reinforcement layer is located outside the area to be excavated in the horizontal channel; Q2-2: Insert a support pipe shed at a position near the top of the cross channel excavation area of ​​the grouting reinforcement layer; Q2-3: The cross passage is obtained by excavating in the area to be excavated using a cut-and-cover method.

[0009] According to the technical solution provided by the present invention, Q3: at the position where the transverse passage is directly opposite the main structure, the arched guide hole is constructed along the first horizontal direction, including: Q3-1: Apply a reinforced layer for the arch-guide tunnel on the inner surface of the transverse channel, facing the main structure and located above the outer side of the area to be excavated in the arch-guide tunnel. Q3-2: Divide the area to be excavated in the arched guide tunnel into multiple sub-regions with intervals between them; Q3-3: Excavate multiple sub-regions along the first horizontal direction using a cut-and-cover method; Q3-4: Install support components at multiple of the aforementioned sub-regions; Q3-5: Install a reinforcing beam inside the transverse passage; the reinforcing beam is used to support the transverse passage and the arched guide tunnel; Q3-6: Using a cut-and-cover method, the area between multiple sub-regions is excavated along the first horizontal direction, and the supporting arch lining and the first transverse diaphragm are applied to obtain the arch guide tunnel.

[0010] According to the technical solution provided by the present invention, Q3-4: Support components are installed at the plurality of said sub-regions, including: Multiple edge stakes are installed at the edge of the sub-region; Multiple central piles are constructed in a sub-region located in the middle of the arched guide tunnel; both the side piles and the central piles are inserted vertically into the excavation area of ​​the main tunnel body; An edge support beam is constructed at the edge of the sub-region; the edge support beam extends along a first horizontal direction and is fixedly connected to a plurality of the edge stakes; A top longitudinal beam is constructed at the top of all sub-regions; the top longitudinal beam extends along a first horizontal direction to support the arched guide tunnel.

[0011] According to the technical solution provided by the present invention, the main structure is excavated vertically using an open-cut construction method until the first target depth is reached, and the method further includes: A first underground continuous wall and a first water-stop curtain with a first target depth are constructed outside the area to be excavated in the main structure; the first target depth is the depth of the bottom surface of the area to be excavated in the main structure of the passage.

[0012] According to the technical solution provided by the present invention, the main body of the tunnel is excavated by a cut-and-cover method, including: The first underground continuous wall directly opposite the arched guide tunnel and the main body of the passage to be excavated area is removed to obtain a connecting tunnel that connects the main structure, the arched guide tunnel and the main body of the passage to be excavated area; The tunnel body is excavated along the first horizontal direction from the connecting tunnel using a cut-and-cover method; simultaneously, the tunnel body is excavated vertically from the junction of the arched guide tunnel and the tunnel body; the tunnel body and the arched guide tunnel form the connecting tunnel.

[0013] According to the technical solution provided by the present invention, the main structure is excavated vertically in an open-cut manner until a first target depth is reached, and before excavating the main body of the tunnel in a cut-and-cover manner, the method further includes: A second water collection pit, a second recharge well, and a main structure support beam are constructed within the main structure.

[0014] The beneficial effects of this invention are as follows: This invention achieves spatial misalignment by excavating temporary shafts and transverse passages at a predetermined, offset location from the main structure while simultaneously excavating the main structure, creating an independent working face. Furthermore, by simultaneously carrying out the excavation and support work for the arch-guide tunnel from the transverse passage with the main structure construction, temporal superposition is achieved. Through this improved strategy of spatial misalignment and temporal superposition, this invention enables parallel construction of both open-cut and tunnel excavation operations.

[0015] In terms of construction efficiency, this invention transforms the original sequential construction sequence into a parallel construction method, allowing the construction of the arch guide tunnel to proceed simultaneously with the construction of the main structure, thereby effectively compressing the total construction period.

[0016] In terms of safety and controllability, this invention pre-treats and finely controls the risks of ground disturbance and water inrush during the underground excavation process by using cross-channel grouting, pipe roof support, zoned excavation, and pre-construction of support components such as side piles and center piles. This reduces construction risks and improves the overall safety level of construction. Attached Figure Description

[0017] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram illustrating the simultaneous execution of step Q1 during step S2. Figure 2 This is a schematic diagram illustrating the simultaneous execution of step Q2 during step S2. Figure 3 This is a schematic diagram illustrating the simultaneous execution of step Q3 during step S2. Figure 4 This is a schematic diagram for step S4; Figure 5 A top-down structural diagram of the underground space of a subway station; Figure 6 This is a schematic diagram of the main structure of the horizontal passageway; Figure 7 This is a side view of the arched guide tunnel. Figure 8 This is a side view of the structure on the other side of the arched guide tunnel; Figure 9 A side view of the main structure; Figure 10 A schematic diagram of the main structure of part of the underground space of a subway station; The components are as follows: 1. Main structure; 2. Connecting passage; 3. Arch-mounted guide tunnel; 4. Passage body; 5. Temporary shaft; 6. Horizontal passage; 7. First designated position; 8. Second diaphragm wall; 9. Second water-stop curtain; 10. First sump; 11. First recharge well; 12. Grouting reinforcement layer of horizontal passage; 13. Supporting pipe shed; 14. Arch-mounted guide tunnel reinforcement layer; 15. Reinforcing beam; 16. Arch-mounted secondary lining; 17. First transverse diaphragm; 18. Side pile; 19. Middle pile; 20. Side support beam; 21. Top longitudinal beam; 22. First diaphragm wall; 23. First water-stop curtain; 24. Connecting tunnel; 25. Second sump; 26. Second recharge well; 27. Main structure support beam; 28. Temporary support. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] It should be noted that: since the description of each part of the space in this embodiment includes two states, one is the unexcavated state and the other is the excavated state; in order to distinguish the two states of the same location, the "area to be excavated" referred to in this embodiment is the unexcavated space.

[0021] This invention provides a rapid construction method for cut-and-cover subway stations in the Quanhu area, comprising: The underground structure of the subway station includes: a main structure 1 and two connecting passages 2 that are interconnected; the two connecting passages 2 are symmetrically arranged on both sides of the main structure 1, and the axis of the connecting passage 2 extends along a first horizontal direction; the first horizontal direction is the direction of travel of the subway train; the connecting passage 2 includes: an arched guide tunnel 3 and a passage body 4 that are interconnected; the arched guide tunnel 3 is located directly above the passage body 4; The first and second horizontal directions are mutually perpendicular; the vertical direction is the direction of gravity, and is perpendicular to both the first and second horizontal directions. The first horizontal direction is... Figure 1-4 The middle X direction, the second horizontal direction is Figure 1-4 Center Y direction.

[0022] Figure 1-4 The shaded area in the image represents the working face during construction (the face that is continuously advanced when excavating a tunnel).

[0023] The method includes: S1: Construct a first underground continuous wall 22 and a first water-stop curtain 23 with a first target depth outside the area to be excavated in the main structure 1; the first target depth is the depth of the bottom surface of the area to be excavated in the main body of the channel 4.

[0024] The first diaphragm wall 22 is a commonly used support structure in underground engineering, used to support the surrounding strata and prevent collapse. The first water-stop curtain 23 is a continuous water-stopping system set around the main body of the project. Through the coordinated action of retaining piles, water-stop bodies, and supporting structures, it blocks the seepage of groundwater inside and outside the foundation pit, effectively blocking the seepage path of groundwater in sand layers, fractured zones, or karst development areas, reducing the permeability coefficient to 10. -6 Up to 10 -8 On the order of cm / s.

[0025] In the specific construction process, on the outside of the area to be excavated in the main structure 1, a first diaphragm wall 22 and a matching first water-stop curtain 23 are first constructed. The specific construction process is not detailed here. The depth of the first diaphragm wall 22 and the first water-stop curtain 23 should reach a first target depth, which is determined based on the design elevation of the bottom surface of the area to be excavated in the main structure 4. This ensures that the main structure 1 can be supported in the area at and above the first target depth, and minimizes the infiltration of groundwater.

[0026] S2: Excavate the main structure 1 vertically using open-cut construction until the first target depth is reached; during the excavation of the main structure 1, steps Q1 to Q3 are performed simultaneously. Because the main structure 1 occupies a large space, the excavation process takes a long time. Existing technologies require excavating the main structure first, followed by excavating the connecting passage 2. This method is time-consuming and inefficient. In this embodiment, excavating the connecting passage 2 simultaneously with excavating the main structure 1 significantly improves construction efficiency and shortens construction time.

[0027] Specifically, in this embodiment, during the excavation of the main structure 1, steps Q1 to Q3 are executed simultaneously, wherein: Step Q1 involves excavating a temporary shaft 5 vertically using an open-cut construction method; Step Q2 involves excavating a horizontal passage 6 from the temporary vertical shaft 5 using a cut-and-cover method. Step Q3 is based on the excavation of the arched guide tunnel 3 in the transverse passage 6; At this point, the method of excavating the main tunnel 4 can be selected according to the construction progress of the main structure 1, as shown in the following example: First construction scenario: If the main structure 1 is not excavated when the arch guide tunnel 3 is completed, the main tunnel 4 can be excavated downwards from the arch guide tunnel 3 in advance; The second construction scenario: If the main structure 1 is completed just as the excavation of the arch guide tunnel 3 is finished, then after removing the first underground continuous wall 22 that is directly opposite the main tunnel 4, a part of the main tunnel 4 close to the main structure 1 can be excavated along the first direction, while another part of the main tunnel 4 can be excavated downward from the arch guide tunnel 3. The third construction scenario: If the main structure 1 is completed first, then the main tunnel 4 needs to be excavated in accordance with the second construction scenario after the arch-guide tunnel 3 is completed.

[0028] The above three construction scenarios are merely illustrative examples and do not represent all possible scenarios. In all three scenarios, the main structure 1 and steps Q1 to Q3 can be constructed concurrently, and the construction plan can be freely adjusted according to the actual construction progress to ensure high construction efficiency.

[0029] Specifically, steps Q1 to Q3 are as follows: Q1: Using open-cut construction, a temporary shaft 5 is excavated vertically at a first predetermined position 7 that is offset from the main structure 1 along the second horizontal direction; the second horizontal direction is perpendicular to the first horizontal direction. Specifically, the first designated position 7 is located at a position that is offset from the main structure 1 along the second direction.

[0030] In some implementations, the distance between the first set position 7 and the edge of the main structure 1 near the first set position 7 can be calculated based on the construction time required for the main structure 1.

[0031] The specific process includes: The construction time of the transverse passage 6 and the main structure 1 are estimated. Then, based on the difference between the construction time of the main structure 1 and the transverse passage 6, the product of this difference and the time required to construct the arch guide tunnel 3 is calculated. This yields the distance that the arch guide tunnel 3 can be constructed at the completion of the main structure 1, i.e., the distance between the first predetermined position 7 and the edge of the main structure 1. Finally, the first predetermined position 7 can be obtained based on the position of the main structure 1.

[0032] This allows the transverse passage 6 to avoid interference with the main structure 1 when excavating along the second direction; the transverse passage 6 excavated in this way can be directly aligned with the main structure 1 along the first direction, which facilitates the subsequent excavation of the arch guide tunnel 3.

[0033] In some embodiments, the first designated position 7 is located on one side or directly above the arched guide tunnel 3.

[0034] When the first set position 7 is directly above the arched guide tunnel 3, after the excavation of the temporary shaft 5 is completed, the transverse passage 6 can be excavated simultaneously from both sides of the temporary shaft 5, thereby further improving construction efficiency.

[0035] refer to Figure 1 Step Q1 specifically includes: Q1-1: Construct a second underground continuous wall 8 and a second water-stop curtain 9 with a second target depth at the first designated location; The second diaphragm wall 8 is used to support the side walls of the temporary shaft to prevent collapse; the second water-stop curtain 9 is used to prevent groundwater from seeping into the temporary shaft 5. The second target depth is the depth at the junction of the arched guide tunnel 3 and the main channel 4, and is less than the first target depth; Q1-2: Using open-cut construction, excavate vertically at the first designated location 7 until the second target depth is reached to obtain an initial temporary shaft; Q1-3: Construct the first collection pit 10 and the first recharge well 11 within the initial temporary shaft to obtain the temporary shaft 5.

[0036] The first collection pit 10 is used to store a small amount of infiltrated groundwater; the first recharge well 11 is used to discharge the infiltrated groundwater.

[0037] The initial temporary shaft is located before the construction of the first sump 10 and the first recharge well 11. Because of the absence of these features, groundwater is easily seeped into the shaft, making construction at this stage quite dangerous. The first sump 10 and the first recharge well 11 must be constructed first to collect the seeping groundwater and drain it from the temporary shaft before construction can continue.

[0038] Q2: Using the cut-and-cover method, excavate a transverse passage 6 along the second horizontal direction at the second target depth inside the inner wall of the temporary shaft 5; the second target depth is the design boundary elevation between the arched guide tunnel 3 and the main body of the passage 4. Specifically, the bottom depth of the transverse passage 6 is the second target depth, which is consistent with the design boundary elevation of the arched guide tunnel 3 and the main body of the passage 4. The height of the transverse passage 6 is greater than that of the arched guide tunnel 3, and the length of the transverse passage 6 along the second horizontal direction is greater than the width of the arched guide tunnel 3 along the second horizontal direction. This allows the arched guide tunnel 3 to be completely excavated by using the inner wall of the transverse passage 6 as the starting point for excavation.

[0039] refer to Figure 2 Step Q2 specifically includes: Q2-1: At the second target depth of the inner wall of the temporary shaft 5, a horizontal channel grouting reinforcement layer 12 is constructed along the second horizontal direction on the side close to the main structure 1; the length of the horizontal channel grouting reinforcement layer 12 along the second horizontal direction is equal to the length of the horizontal channel 6 along the second horizontal direction; The transverse channel grouting reinforcement layer 12 is located above and outside the area to be excavated in the transverse channel 6, enclosing the area to be excavated and providing support. After the transverse channel grouting reinforcement layer 12 is completed, a hole is opened to check the grouting effect at this section to see if there is any water flow, ensuring that the soil has solidified and is water-free. Pre-constructing the transverse channel grouting reinforcement layer 12 can prevent the top or sidewalls from collapsing during the construction of the transverse channel 6, thus avoiding potential dangers.

[0040] Q2-2: Insert multiple support pipe sheds 13 at the position of the grouting reinforcement layer 12 of the transverse channel near the top of the excavation area of ​​the transverse channel 6; The supporting pipe shed 13 is made of steel pipe, and multiple supporting pipe sheds 13 are parallel to each other to support the top of the horizontal channel grouting reinforcement layer 12, thereby improving the structural strength of the top and reducing the risk of collapse.

[0041] Q2-3: The cross passage 6 is obtained by excavation in the area to be excavated using the cut-and-cover method.

[0042] Specifically, the cross passage 6 is excavated using the bench method, with bench lengths ranging from 3m to 5m in this embodiment. The bench method is a tunnel construction method primarily applicable to Class I-IV hard rock and Class II-III soft rock strata. Its construction principle involves first excavating the upper section of the tunnel (the upper bench), then advancing the upper bench a certain distance before excavating the lower section, with both upper and lower benches progressing simultaneously. Based on bench length, the bench method can be categorized into short bench method, long bench method, and ultra-short bench method.

[0043] The length of the transverse passage 6 along the second direction is greater than the width of the main passage 4 along the second direction, thus providing sufficient space for movement during the subsequent excavation of the main passage 4, facilitating the underground excavation.

[0044] Q3: At the position where the transverse passage 6 is directly opposite the main structure 1, the arched guide hole 3 is constructed along the first horizontal direction; As the top support of the main channel 4, the stability of the arched guide tunnel 3 is crucial; therefore, sufficient support needs to be added to the arched guide tunnel 3 during the excavation process.

[0045] refer to Figure 3 Step Q3 includes: Q3-1: On the inner surface of the transverse channel 6, facing the main structure 1 and located above the outer side of the area to be excavated in the arched guide tunnel 3, a reinforced layer 14 for the arched guide tunnel is constructed. In this embodiment, constructing the arch-guide tunnel reinforcement layer 14 only within the soil above serves to support the arch-guide tunnel 3 while avoiding interference with the main tunnel body 4. During the construction of the arch-guide tunnel reinforcement layer 14, reinforcing beams are pre-embedded, and after its completion, steel pipes are inserted near the top of the arch-guide tunnel as supports. This further enhances the structural strength of the arch-guide tunnel reinforcement layer 14 and reduces the risk of collapse.

[0046] Q3-2: Divide the area to be excavated in the arched guide tunnel 3 into multiple sub-regions with intervals between them; Q3-3: Excavate multiple sub-regions along the first horizontal direction using a cut-and-cover method; Q3-4: At multiple sub-regions, construct support components; the support components are used to support multiple excavated sub-regions to prevent collapse.

[0047] If continuous underground spaces are excavated by tunneling, there is a high probability of central collapse. Therefore, in this embodiment, the method of excavating interspersed sub-regions is adopted, using the underlying layers between the sub-regions as temporary supports. After the sub-regions are excavated and additional support structures are added, the strata between the sub-regions are then excavated to connect multiple sub-regions and form the arched guide tunnel 3.

[0048] The supporting components include: side piles 18, middle piles 19, side support beams 20, and top longitudinal beams 21.

[0049] refer to Figure 7 Steps Q3-4 include: Multiple edge stakes 18 are installed at the edge of the sub-region; Multiple central piles 19 are constructed in the sub-region located in the middle of the arched guide tunnel 3; both the side piles 18 and the central piles 19 are inserted vertically into the excavation area of ​​the main channel body 4. An edge support beam 20 is constructed at the edge of the sub-region; the edge support beam 20 extends along a first horizontal direction and is fixedly connected to a plurality of the edge stakes 18; A top longitudinal beam 21 is constructed on top of all sub-regions; the top longitudinal beam 21 extends along a first horizontal direction to support the arched guide hole 3.

[0050] Specifically, multiple edge piles 18 are constructed at the edges of the two farthest sub-regions that are far apart from each other; and edge support beams 20 are constructed at the edges of the two farthest sub-regions that are far apart from each other.

[0051] Side piles 18, center piles 19, side support beams 20, and top longitudinal beams 21 are all used to support various parts of the arch-guide tunnel 3. At the same time, the parts inserted into the main body of the tunnel 4 can also provide support when excavating the main body of the tunnel 4, preventing the side walls from collapsing during the excavation of the main body of the tunnel 4.

[0052] Q3-5: Reference Figure 6 A reinforcing beam 15 is installed inside the transverse passage 6; the reinforcing beam 15 is used to support the transverse passage 6 and the arched guide hole 3. In this embodiment, since both sides of the transverse passage 6 are connected to the arched guide tunnel 3, it is necessary to set up reinforcing beams 15 on both sides for support to avoid collapse when excavating the strata between sub-regions.

[0053] Q3-6: Using the method of tunnel excavation, the area between multiple sub-regions is excavated along the first horizontal direction, and the supporting arch lining 16 and the first transverse diaphragm 17 are applied to obtain the arch guide tunnel 3.

[0054] In this embodiment, the area to be excavated in the arch-guide tunnel 3 is divided into multiple sub-regions with intervals between them; and the multiple sub-regions are excavated by cut-and-cover method; the intervals between the sub-regions are used to support the entire arch-guide tunnel to prevent collapse, and support components are installed at the same time. Then, after the support components are installed, the remaining areas between the sub-regions are excavated.

[0055] Construction in the above manner can support the underground structure, prevent the collapse of the arched guide tunnel during the excavation process, and ensure the safety of construction.

[0056] refer to Figure 7-8 The specific excavation method for the arch-guide tunnel is the step method. As the excavation progresses, the arch-guide tunnel grid steel frame is constructed in the completed section. After the first and last ends of the arch-guide tunnel grid steel frame are connected to form a ring, H-beams (i.e., reinforcing beams 15) need to be constructed in a timely manner at the junction of the arch-guide tunnel and the cross passage. The tunnel face is staggered at least 5m along the first direction as a temporary support 28.

[0057] After the support components for the arched guide tunnel are installed, reinforcing beam 15 should be installed in a timely manner to reinforce the transverse passage and prevent it from collapsing.

[0058] According to the construction plan, the construction of the waterproof structure on both sides and the arch lining 16 will be carried out. According to the grouping of the length of the arch lining 16, the temporary support 28 will be removed in sections, each section not exceeding one column span (column span refers to the horizontal distance between two adjacent columns). In order to facilitate the waterproof construction and the arch lining 16 construction, an additional 1m of temporary support 28 will be removed from the original removal range, leaving only the steel support.

[0059] S3: Reference Figure 5 Within the main structure 1, a second water collection pit 25, a second recharge well 26, and a main structure support beam 27 are constructed. The second water collection pit 25 is used to collect groundwater that has seeped into the main structure, the second recharge well 26 is used to discharge the seeping groundwater, and the main structure support beam 27 is installed on the side surface of the main structure 1 to support the side wall of the main structure 1 after excavation and prevent collapse.

[0060] The tunnel body 4 is excavated using a cut-and-cover method; the arched guide tunnel 3 and the tunnel body 4 form the connecting tunnel 2.

[0061] In one implementation plan, the main structure 1 can be excavated first, and then the main tunnel 4 can be excavated simultaneously in both directions, according to the construction schedule. (Reference) Figure 4 and Figure 10 Step S4 includes: S4-1: Reference Figure 9 The first underground continuous wall 22, which is directly opposite the area to be excavated of the arched guide tunnel 3 and the main body of the passage 4, is removed to obtain a connecting tunnel 24 that connects the main structure, the arched guide tunnel 3 and the area to be excavated of the main body of the passage 4; the connecting tunnel 24 connects the main structure 1 and the main body of the passage 4.

[0062] After breaking through the first underground continuous wall 22 between the main structure 1 and the main tunnel 4, the main tunnel 4 can be excavated from one side of the main structure 1 along the first direction; in conjunction with excavating the main tunnel 4 in different directions within the arched guide tunnel 3, the construction progress can be accelerated.

[0063] S4-2: Using the method of tunneling, the main body of the channel 4 is excavated from the connecting tunnel 24 along the first horizontal direction; at the same time, the main body of the channel 4 is excavated vertically from the junction of the arched guide tunnel 3 and the main body of the channel 4; the main body of the channel 4 and the arched guide tunnel 3 form the connecting channel 2.

[0064] In this embodiment, the tunnel body is excavated from multiple locations along different directions. Compared with the method of excavating only along the first horizontal direction, the tunnel body can be excavated more quickly, further improving construction efficiency.

[0065] Specifically, the main body of the tunnel is divided into multiple sections along the first horizontal direction. One section, which is close to the main structure, is excavated by cutting along the first horizontal direction. The other sections are excavated by cutting downwards using the self-locking arch guide tunnel 3.

[0066] After excavation is completed, waterproof and base slab structures should be constructed promptly, followed by the remaining side walls, to ensure the structure is closed circumferentially as soon as possible.

[0067] In another implementation, once the excavation and necessary construction of the arched guide tunnel 3 are completed, the main tunnel body 4 can be excavated vertically downwards from the arched guide tunnel 3 without waiting for the main structure 1 to be excavated. After the main structure 1 is excavated, the first underground continuous wall 22 facing the area to be excavated of the arched guide tunnel 3 and the main tunnel body 4 can be removed to connect the main structure 1 with the arched guide tunnel 3 and the main tunnel body 4.

[0068] Alternatively, based on the actual construction progress of the main structure 1, the following steps may be performed: After the excavation of the arched guide tunnel 3 and the necessary construction are completed, the main body of the passage 4 is divided into sections, including the main body of the passage 4 close to the main structure 1 and the main body of the passage 4 far away from the main structure 1. The self-locking arch guide tunnel 3 is excavated vertically downwards, and the main channel 4 is excavated in a section away from the main structure 1. During this process, the main structure 1 is completed, and then the first underground continuous wall 22 facing the area to be excavated between the self-locking arch guide tunnel 3 and the main channel 4 is removed. Then, the main channel 4 is excavated in the first horizontal direction, and the section close to the main structure 1 is excavated. Finally, the main channel 4 excavated in the two directions can be completed almost simultaneously.

[0069] Based on the above construction plan, the tunnel arch is excavated simultaneously during the open-cut main structure excavation; after the main structure is excavated, only the tunnel main body needs to be excavated. Compared with the method of excavating the main structure first and then excavating the tunnel arch and tunnel main body, this method has higher construction efficiency and effectively shortens the construction cycle.

[0070] At this point, the main structure 1 and connecting passage 2 required for the subway station are obtained; subsequently, the construction of the facilities inside the station can be carried out according to the construction schedule.

[0071] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention is not limited to the specific combination of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A rapid construction method for a cut-and-cover subway station in the Quanhu area, wherein the underground structure of the subway station includes: The main structure (1) and two connecting channels (2) are interconnected; the two connecting channels (2) are symmetrically arranged on both sides of the main structure (1), and the axis of the connecting channel (2) extends along a first horizontal direction; the first horizontal direction is the direction of travel of the subway train; the connecting channel (2) is characterized in that: the connecting channel (2) includes: an arched guide hole (3) and a channel body (4) that are interconnected; the arched guide hole (3) is located directly above the channel body (4); The method includes: The main structure (1) is excavated vertically using an open-cut method until the first target depth is reached; during the excavation of the main structure (1), steps Q1 to Q3 are performed simultaneously. Q1: Using open-cut construction, a temporary shaft (5) is excavated vertically at a first predetermined position (7) that is offset from the main structure (1) along the second horizontal direction; the second horizontal direction is perpendicular to the first horizontal direction. Q2: Using the method of tunnel excavation, a transverse passage (6) is excavated along the second horizontal direction at the second target depth of the inner wall of the temporary shaft (5); the second target depth is the design boundary elevation between the arched guide tunnel (3) and the main body of the passage (4); Q3: At the position of the transverse passage (6) directly opposite the main structure (1), the arched guide hole (3) is constructed along the first horizontal direction. The tunnel body (4) is excavated by tunneling; the arched guide tunnel (3) and the tunnel body (4) form the connecting tunnel (2).

2. The rapid construction method for cut-and-cover subway stations in the Quanhu area according to claim 1, characterized in that, Q1: Using open-cut construction, a temporary shaft (5) is excavated vertically at a first predetermined position (7) offset from the main structure (1) along the second horizontal direction, including: Q1-1: Construct a second underground continuous wall (8) and a second water-stop curtain (9) with a second target depth at the first set position (7); Q1-2: Using open-cut construction, excavate vertically at the first designated position (7) until the second target depth is reached to obtain the initial temporary shaft; Q1-3: Construct the first sump (10) and the first recharge well (11) within the initial temporary shaft to obtain the temporary shaft (5).

3. A rapid construction method for open-cut and cut-and-cover subway stations in the Quanhu area according to claim 1, characterized in that, Q2: using cut-and-cover construction, a transverse passage (6) is excavated along the second horizontal direction at the second target depth of the inner wall of the temporary shaft (5), including: Q2-1: At the second target depth of the inner wall of the temporary shaft (5), a horizontal channel grouting reinforcement layer (12) is constructed along the second horizontal direction on the side close to the main structure (1); the horizontal channel grouting reinforcement layer (12) is located outside the area to be excavated in the horizontal channel (6); Q2-2: Insert a support pipe roof (13) into the grouting reinforcement layer (12) of the transverse channel near the top of the area to be excavated in the transverse channel (6); Q2-3: The cross passage (6) is excavated in the area to be excavated by tunneling to obtain the cross passage (6).

4. The rapid construction method for cut-and-cover subway stations in the Quanhu area according to claim 1, characterized in that, Q3: At the position of the transverse passage (6) directly opposite the main structure (1), the arched guide hole (3) is constructed along the first horizontal direction, including: Q3-1: On the inner surface of the transverse passage (6) facing the main structure (1) and located above the outer side of the area to be excavated in the arch guide tunnel (3), a reinforced layer (14) for the arch guide tunnel is constructed. Q3-2: Divide the area to be excavated in the arched guide tunnel (3) into multiple sub-regions with intervals between them; Q3-3: Excavate multiple sub-regions along the first horizontal direction using a cut-and-cover method; Q3-4: Install support components at multiple of the aforementioned sub-regions; Q3-5: Install a reinforcing beam (15) inside the transverse passage (6); the reinforcing beam (15) is used to support the transverse passage (6) and the arched guide tunnel (3); Q3-6: Using the method of tunneling, the area between multiple sub-areas is excavated along the first horizontal direction, and the supporting arch lining (16) and the first transverse diaphragm (17) are applied to obtain the arch guide tunnel (3).

5. A rapid construction method for open-cut and cut-and-cover subway stations in the Quanhu area according to claim 4, characterized in that, Q3-4: At the multiple sub-regions, construct support components, including: Multiple edge stakes (18) are installed at the edge of the sub-region. Multiple central piles (19) are constructed in the sub-region located in the middle of the arched guide tunnel (3); both the side piles (18) and the central piles (19) are inserted vertically into the excavation area of ​​the main body of the channel (4); An edge support beam (20) is constructed at the edge of the sub-region; the edge support beam (20) extends along a first horizontal direction and is fixedly connected to a plurality of the edge stakes (18); A top longitudinal beam (21) is constructed on top of all sub-regions; the top longitudinal beam (21) extends along a first horizontal direction to support the arched guide hole (3).

6. A rapid construction method for cut-and-cover subway stations in the Quanhu area according to claim 1, characterized in that, The main structure (1) is excavated vertically using an open-cut method until the first target depth is reached, which also includes: A first underground continuous wall (22) and a first water-stop curtain (23) with a first target depth are constructed outside the excavation area of ​​the main structure (1); the first target depth is the depth of the bottom surface of the excavation area of ​​the main channel (4).

7. A rapid construction method for cut-and-cover subway stations in the Quanhu area according to claim 6, characterized in that, The main body of the tunnel (4) is excavated using a cut-and-cover method, including: The first underground continuous wall (22) facing the area to be excavated between the arched guide tunnel (3) and the main body of the passage (4) is removed to obtain a connecting tunnel (24) connecting the main structure (1), the arched guide tunnel (3) and the main body of the passage (4) to be excavated. Using the method of tunnel excavation, the main body of the channel (4) is excavated from the connecting tunnel (24) along the first horizontal direction; at the same time, the main body of the channel (4) is excavated vertically from the junction of the arched guide tunnel (3) and the main body of the channel (4); the main body of the channel (4) and the arched guide tunnel (3) form the connecting channel (2).

8. A rapid construction method for cut-and-cover subway stations in the Quanhu area according to claim 1, characterized in that, The main structure (1) is excavated vertically using open-cut construction until the first target depth is reached. Before excavating the main body of the tunnel (4) using cut-and-cover construction, the following steps are also included: A second water collection pit (25), a second recharge well (26), and a main structure support beam (27) are constructed within the main structure (1).

Images