Construction method for efficiently breaking down enclosure structure shared by underground engineering main body and accessory structure

Abstract

The invention belongs to the technical field of constructional engineering, provides a construction method for efficiently breaking an enclosure structure shared by an underground engineering main body and an accessory structure, and aims to solve the problems of low efficiency and serious pollution caused by breaking the underground engineering in a mode of combining rope saw cutting and an air pick machine. The first area and the third area of the enclosure structure are subjected to static expansion breaking through the expanding agent, the second area with the large area is subjected to cutting breaking through the rope saw, the breaking efficiency can be improved, and meanwhile noise pollution and flying dust pollution generated when the maintenance structure is broken are reduced. The underground engineering can be entirely and comprehensively capped, and underground water is prevented from entering the underground engineering; and meanwhile, the influence on the existing underground engineering is eliminated.

Description

Technical Field

[0001] This invention belongs to the field of building engineering technology, specifically relating to a construction method for efficiently breaking down the retaining structure shared by the main body and auxiliary structures of underground engineering projects. Background Technology

[0002] The demand for urban underground space development is increasing, and the intersections between subway lines and between subway lines and real estate developments have created many challenges for engineers: such as how to ensure that the two lines do not conflict and can achieve the best functional use when they intersect, safety and construction efficiency during the construction process, environmental protection issues, and cost optimization issues.

[0003] For example, regarding the enclosure structure between a subway ventilation shaft (auxiliary structure) and the main structure (main project), current technology typically uses a combination of wire saw cutting and pneumatic drills to demolish the enclosure structure where the auxiliary structure and the main project share a wall. This method has the following problems in actual construction:

[0004] (1) Currently, wire saw cutting is carried out according to the set modules, that is, the enclosure structure is pre-divided into multiple modules, water drill holes are made at the four corners of each module to form cutting holes, and then the wire saw cutting machine is used to cut each module in sequence. This method has too many cutting holes drilled, resulting in low efficiency of enclosure structure demolition.

[0005] (2) When using a pneumatic hammer for demolition, there is not only a lot of noise and dust pollution, but also a problem of low demolition efficiency. Summary of the Invention

[0006] This invention addresses the problems of low efficiency and severe pollution associated with existing methods that combine wire saws and pneumatic drills to demolish the shared walls of underground engineering structures. It provides a highly efficient construction method for demolishing these shared walls, employing different demolition methods for structures at different heights to improve demolition efficiency and reduce noise and dust pollution. More importantly, by rapidly demolishing the shared walls between the main structure and auxiliary structures, the entire underground project can be completely sealed, preventing groundwater from entering and eliminating any impact on the existing underground structure (main structure and auxiliary structures).

[0007] To solve the technical problem, the technical solution adopted by this invention is as follows:

[0008] A construction method for efficiently breaking down the retaining structure shared by the main body and auxiliary structures of an underground engineering project includes:

[0009] (1) After the main construction of the underground project is completed, the auxiliary structure is constructed; when constructing the top and bottom slabs of the auxiliary structure, a reserved space is reserved between the top and bottom slabs of the auxiliary structure and the enclosure structure of the main project for the pouring of the post-pouring strip;

[0010] (2) The enclosure structure at the point where the main structure and the ancillary structure share a wall shall be demolished, including the following:

[0011] (2.1) The enclosure structure is divided according to its height position. The enclosure structure above the upper surface of the top plate of the auxiliary structure is called the first area, the enclosure structure between the bottom plate and the top plate of the auxiliary structure is called the second area, and the enclosure structure below the upper surface of the bottom plate of the auxiliary structure is called the third area. The bottom end of the third area is spaced from the lower end of the bottom plate so as to expose part of the main reinforcement in the enclosure structure.

[0012] (2.2) Static expansion is used to break up the first and third areas of the enclosure structure using an expansion agent, and wire saw is used to break up the second area of ​​the enclosure structure. During the process of breaking up the enclosure structure, the first, second and third areas are broken up in sequence.

[0013] In some embodiments, after the enclosure structure is demolished, post-cast strips are poured in the spaces reserved in the bottom and top slabs of the auxiliary structure so that the bottom and top slabs of the auxiliary structure are connected to the structural frame columns of the main project; when pouring the post-cast strip at the bottom slab of the auxiliary structure, the main reinforcement bars after the third area of ​​the enclosure structure is demolished are anchored into the bottom slab so that the enclosure structure below the bottom slab that has not been demolished forms an integral whole with the bottom slab.

[0014] In some embodiments, when breaking down the first and third regions of the enclosure structure in step (2.2), vertical holes are first drilled downwards to form plum blossom-shaped holes, and a prepared expanding agent is placed into the holes. The plum blossom-shaped holes include a row of holes close to the structural frame columns of the main project and arranged along the length of the enclosure structure, and other rows of holes further away from the structural frame columns of the main project. The distance between the quadrant point of the structural frame column closer to the main project in the row of holes and the outer side of the structural frame column close to the main project on the enclosure structure is X. X is less than the radius R of the hole and greater than half of the radius R of the hole.

[0015] In some embodiments, when statically expanding and breaking the first region of the enclosure structure with an expanding agent, segmented breaking is adopted, and when performing segmented breaking, pre-crack holes or pre-cracks are opened on the exposed side of the enclosure structure, the positions of the pre-crack holes or pre-cracks corresponding to the positions of the upper surface of the top plate.

[0016] In some embodiments, when breaking the second region of the enclosure structure in step (2.2), circumferential water drill holes are evenly opened around the perimeter of the second region, and a row of vertical water drill holes is opened in the middle of the length direction of the second region of the enclosure structure. The wire saw cutter divides the second region of the enclosure structure into several blocks along the layout of the circumferential water drill holes and performs block cutting in the direction from top to bottom.

[0017] In some embodiments, when breaking down the third region of the enclosure structure in step (2.2), before opening the plum blossom-shaped openings in the vertical direction, the upper surface of the third region is first cut to form an open surface, and then static expansion is carried out using the openings and the prepared expansion agent.

[0018] In some embodiments, segmented demolition is employed when static expansion demolition of the third region of the enclosure structure is carried out using an expansion agent, while retaining the main reinforcement bars within the enclosure structure.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention uses an expanding agent for static expansion and demolition in the first and third regions, while using a wire saw for demolition in the larger second region. Compared with the existing technology that uses pneumatic picks and wire saws for demolition, this invention can improve demolition efficiency while reducing noise and dust pollution during the demolition of the maintenance structure.

[0021] This invention optimizes the placement of the expansion holes. When the expansion agent in a row of expansion holes statically expands and breaks through the enclosure structure, the enclosure structure side near the main structure's structural frame columns can quickly rupture and release the expansion force, reducing the squeezing impact on the main structure's structural frame columns during enclosure structure demolition and avoiding the structural impact on the main structure caused by static expansion demolition.

[0022] This invention guides the retaining structure to fracture and collapse along its length using pre-cracked holes or cracks, further reducing the impact of compression on the main structure. Simultaneously, the use of segmented fracture to statically expand and fracture the first region of the retaining structure ensures that each segment can have pre-cracked holes or cracks, thereby guiding each segment of the first region to expand and fracture along the length of the retaining structure, further reducing the impact of compression on the main structure and ensuring its safety.

[0023] This invention utilizes a combination of circumferential and vertical water-drilled holes for wire saw cutting. Compared to existing technologies that distribute water-drilled holes at the four corners of each segment, this method not only completes segmented cutting but also significantly reduces the number of water-drilled holes, thereby reducing construction time and costs.

[0024] This invention utilizes an expanding agent to statically expand and break up the third region of the enclosure structure, which avoids the vibration impact of the pneumatic drill on the main structure. At the same time, by optimizing the drilling site and adopting a segmented breaking method, the impact on the main structure (the structural frame columns of the main structure) can be reduced, ensuring the structural safety of the main structure.

[0025] In summary, this invention employs different demolition methods for the retaining structure at different heights, which improves the demolition efficiency and reduces noise and dust pollution during the entire demolition process. More importantly, because it can quickly demolish the retaining structure at the shared wall between the main structure and the auxiliary structures, it can expedite the overall capping of the underground project, preventing groundwater from entering the underground project; at the same time, it eliminates the impact on the existing underground project (main structure and auxiliary structures). Attached Figure Description

[0026] Figure 1 This is a plan view of the main structure and auxiliary structure according to an embodiment of the present invention, wherein only a portion of the main structure near the auxiliary structure is shown.

[0027] Figure 2 for Figure 1 The schematic diagram of the cross section at point AA shows that, in order to show the location of the reserved space, a post-cast strip for the top slab is added within the reserved space of the top slab of the auxiliary structure, and a post-cast strip for the bottom slab is shown within the reserved space of the bottom slab of the auxiliary structure.

[0028] Figure 3 for Figure 1 A schematic cross-sectional view at point BB;

[0029] Figure 4 A schematic diagram showing the arrangement of pre-cracks, pre-splitting holes, or pre-cracks in the first area of ​​the enclosure structure;

[0030] Figure 5 This is a schematic diagram of the enclosure structure (i.e., the second area of ​​the enclosure structure) between the top and bottom plates of the auxiliary structure using a wire saw cutting machine.

[0031] Markings in the diagram: 1. Main structure, 11. Main structure top slab, 12. Structural frame column, 13. Main structure bottom slab, 2. Auxiliary structure, 21. Auxiliary structure top slab, 22. Auxiliary structure bottom slab, 23. Top slab post-cast strip, 24. Bottom slab post-cast strip, 3. Enclosure structure, 31. Main reinforcement, 32. Circumferential water drill hole, 33. Vertical water drill hole, 34. Cutting line, 35. Chemical hole, 36. Pre-crack hole or pre-crack. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are some, but not all, of the embodiments of the present invention. The following embodiments are only for specific illustration of the implementation methods of the present invention and do not limit the scope of protection of the present invention.

[0033] Combined with appendix Figure 1 To be continued Figure 3 The underground project includes the main structure 1 and the auxiliary structure 2. The main structure includes the main structure top slab 11, structural frame columns 12, and main structure bottom slab 13. The auxiliary structure 2 includes structural frame columns, auxiliary structure top slab 21, and auxiliary structure bottom slab 22. The elevations of the main structure top slab 11 and auxiliary structure top slab 21 are compatible, and the elevations of the main structure bottom slab 13 and auxiliary structure bottom slab 22 are compatible. The retaining structure 3 to be demolished is located between the structural frame columns 12 of the main structure and the auxiliary structure 2. Therefore, it is necessary to demolish the retaining structure 3 and connect the auxiliary structure 2 and the main structure 1 together to form a whole through the post-cast top slab post-cast strip 23 and post-cast bottom slab post-cast strip 24. The reason for the existence of the retaining structure 3 between the main structure 1 and the auxiliary structure 2 is that the excavation and construction times of the foundation pits of the main structure 1 and the auxiliary structure 2 are different. Therefore, the retaining structure 3 needs to be demolished between the post-cast top slab strip 23 and the post-cast bottom slab strip 24. The specific structures of the main project 1 and the auxiliary structure 2 of the underground project are clear and understandable to those skilled in the art, and will not be described in detail here.

[0034] Combined with appendix Figure 2 To indicate the location of the reserved space, a post-cast strip 23 is added within the reserved space of the top slab 21 of the auxiliary structure, and a post-cast strip 24 is shown within the reserved space of the bottom slab 22 of the auxiliary structure. Therefore, when the enclosure structure is not demolished, Figure 2 The areas at the locations of the top slab post-cast strip 23 and the bottom slab post-cast strip 24 are blank areas.

[0035] Combined with appendix Figure 1 To be continued Figure 5 The present invention provides a construction method for efficiently breaking down the retaining structure shared by the main body and auxiliary structures of underground engineering projects, comprising:

[0036] (1) After the main project 1 of the underground project is completed, the auxiliary structure 2 is constructed. When constructing the top and bottom slabs of the auxiliary structure 2 (i.e., when constructing the top slab 21 and the bottom slab 22 of the auxiliary structure), a reserved space is reserved between the top and bottom slabs of the auxiliary structure and the enclosure structure 3 of the main project for the pouring of the post-pouring strip. The reserved space at the top slab 21 of the auxiliary structure will form the top slab post-pouring strip 23 after the later pouring, and the reserved space at the bottom slab 22 of the auxiliary structure will form the bottom slab post-pouring strip 24 after the later construction.

[0037] (2) The enclosure structure 3 at the location where the main structure 1 and the auxiliary structure 2 share a wall shall be demolished, specifically including the following:

[0038] (2.1) The enclosure structure 3 is divided according to its height. The enclosure structure 3 above the upper surface of the auxiliary structure top plate 21 is called the first region, the enclosure structure between the bottom plate and the top plate is called the second region, and the enclosure structure below the upper surface of the bottom plate is called the third region. The bottom of the third region is spaced from the lower surface of the bottom plate to expose part of the main reinforcement bars inside the enclosure structure. Since the elevation of the main structure top plate 11 is the same as the elevation of the auxiliary structure top plate 22, and the elevation of the main structure bottom plate 13 is the same as the elevation of the auxiliary structure bottom plate 22, the bottom plate and the top plate are used directly for ease of description, which will be understood by those skilled in the art.

[0039] (2.2) Static expansion is used to break the first and third regions of the enclosure structure 3 using an expansion agent, and wire saw is used to break the second region of the enclosure structure 3. During the process of breaking the enclosure structure, the first, second and third regions are broken in sequence.

[0040] This invention uses an expanding agent for static expansion and demolition in the first and third regions. Compared with the existing technology that uses a pneumatic hammer for demolition, this method can improve demolition efficiency while reducing noise and dust pollution during the demolition of the maintenance structure.

[0041] Combined with appendix Figure 2In some embodiments, after the enclosure structure 3 is demolished, post-cast strips are poured in the reserved spaces of the bottom and top slabs of the auxiliary structure to connect the bottom and top slabs of the auxiliary structure to the structural frame columns of the main structure. That is, a post-cast strip 23 is poured in the reserved space of the top slab 21 of the auxiliary structure (including the space after the enclosure structure is demolished), and a post-cast strip 24 is poured in the reserved space of the bottom slab 22 of the auxiliary structure (including the space after the enclosure structure is demolished). When pouring the post-cast strip at the bottom slab of the auxiliary structure (i.e., when pouring the post-cast strip of the bottom slab), the main reinforcement 31 of the enclosure structure 3 after the third region is demolished is anchored into the bottom slab, so that the enclosure structure 3 below the bottom slab that has not been demolished forms an integral whole with the bottom slab. The retaining structure 3 is pre-embedded with steel bars. Therefore, when the third area of ​​the retaining structure is broken, the main steel bars 31 in the retaining structure 3 are retained, and the grout is injected into the bottom slab post-cast strip 24, so that the retaining structure below the auxiliary structure bottom slab 22 that has not been broken and the bottom slab form a whole, thereby improving the structural strength of the bottom slab.

[0042] In the specific implementation process, the distance between the lower end face of the third region and the lower end face of the auxiliary structure base plate 22 is greater than the thickness of the auxiliary structure base plate 22, so as to improve the structural strength between the undamaged enclosure structure 3 and the auxiliary structure base plate 22.

[0043] However, in existing technologies, when demolishing the retaining structure 3 below the upper surface of the auxiliary structural base slab 22, only a pneumatic drill is used to demolish it down to the lower surface of the auxiliary structural base slab 22, and the main reinforcement 31 of the retaining structure 3 is not preserved. As a result, the later-cast base slab post-tensioning strip 24 forms a whole with the auxiliary structural base slab 22, rendering the undemolished retaining structure 3 completely ineffective. This invention addresses this by, on the one hand, lowering the lower surface of the third region below the lower surface of the auxiliary structural base slab 22, and on the other hand, embedding the main reinforcement 31 of the retaining structure 3 into the base slab post-tensioning strip 24. This allows the undemolished retaining structure 3 below the lower surface of the auxiliary structural base slab 22 to connect with the auxiliary structural base slab 22 through the base slab post-tensioning strip 24, forming a whole. This fully utilizes the function of the undemolished retaining structure 3 to improve the structural strength of the entire underground project.

[0044] Combined with appendix Figure 4In some embodiments, when breaking down the first and third regions of the enclosure structure in step (2.2), vertical holes are first drilled downwards to form plum blossom-shaped holes 35, and a prepared expanding agent is placed into the holes 35. The plum blossom-shaped holes 35 include a row of holes close to the structural frame column 12 of the main project 1 and arranged along the length of the enclosure structure 3, and other rows of holes further away from the structural frame column 12 of the main project 1. The distance between the quadrant point of the structural frame column 12 closer to the main project 1 in the row of holes and the outer side of the structural frame column 12 close to the main project on the enclosure structure 3 is X (in mm). X is less than the radius R of the hole (where the radius R of the hole is in mm) and greater than half of the radius R of the hole. Because the row of expansion holes is closer to or more closely adheres to the structural columns of the main structure, this invention optimizes the placement of these expansion holes. When the expanding agent in one row of expansion holes statically expands and breaks down the enclosure structure, the enclosure structure side closest to the main structure's structural columns can quickly rupture and release the expansion force, reducing the squeezing impact on the main structure's structural columns during enclosure demolition. This avoids the structural impact on the main structure caused by static expansion demolition methods.

[0045] In this invention, one row of eyelets and other rows of eyelets are arranged along the length of the enclosure structure 3, while the other rows of eyelets are arranged along the width of the enclosure structure 3. That is to say, one row of eyelets is closer to the structural frame column 12 of the main project 1 along the width of the enclosure structure, while the other rows of eyelets are farther away from the main project 1 along the width of the enclosure structure 3.

[0046] The expanding agent used in static expansion demolition is existing technology, which is understood by those skilled in the art. In existing technologies, when using expanding agents to demolish engineering structures, the quincunx-shaped expansion holes are evenly distributed throughout the structure. However, since the enclosure structure is generally close to or even adjacent to the structural columns of the main structure, the expanding agent can significantly impact the structural columns during static expansion demolition, potentially severely affecting the structural safety of the main structure in extreme cases. Therefore, existing static expansion demolition methods using expanding agents have not been applied to demolishing enclosure structures adjacent to the structural columns of the main structure. This invention, by optimizing the expansion hole placement, enables static expansion demolition of the enclosure structure above the top slab using expanding agents while avoiding the structural impact on the main structure caused by static expansion demolition.

[0047] In some embodiments, when statically expanding and breaking the first region of the enclosure structure 3 using an expanding agent, segmented breaking is employed. During segmented breaking, pre-cracks or pre-slits 36 are created on the exposed side of the enclosure structure 3. The positions of these pre-cracks or pre-slits 36 correspond to the positions of the upper surfaces of the top plate (attached structure top plate 21). The pre-cracks or pre-slits 36 guide the enclosure structure to fracture and collapse along its length, further reducing the impact of compression on the main structure 1. Simultaneously, the segmented breaking method for static expansion and breaking the first region of the enclosure structure ensures that each segment can have pre-cracks or pre-slits, thereby guiding each segment of the first region to expand and fracture along the length of the enclosure structure, further reducing the impact of compression on the main structure and ensuring its safety.

[0048] Combined with appendix Figure 4 In this schematic diagram, the vertical lines at the pre-crack holes or pre-cracks 36 represent segmentation lines. During implementation, when statically expanding and breaking the first segment of the first region of the retaining structure 3, pre-crack holes or pre-cracks 36 can be simultaneously constructed from the side of the retaining structure at the upper end of the top slab of the auxiliary structure while constructing the quincunx-shaped holes 35. The pre-crack holes or pre-cracks 36 extend 50-100mm into the retaining structure 3 along its length. After the static expansion and breaking of the first segment of the retaining structure in the first region, and after cleaning the broken concrete blocks, pre-crack holes or pre-cracks are constructed from the side of the retaining structure. This cyclical operation ensures that pre-crack holes or pre-cracks can be constructed in every segment of the first region of the retaining structure, thus guiding the breaking of each segment.

[0049] In existing technologies, when using expansion agents to statically expand and demolish building projects, there is no design to create pre-crack holes or pre-cracks. Since the expansion and rupture occurs when the expansion occurs in all directions, the enclosure structure can have a significant impact on the main structure when it is in close contact with the main structure.

[0050] Combined with appendix Figure 5 In some embodiments, when breaking the second region of the enclosure structure 3 in step (2.2), circumferential water drill holes 32 are evenly opened around the second region, and a row of vertical water drill holes 33 is opened in the middle of the length direction of the second region of the enclosure structure 3. The wire saw cutting machine divides the second region of the enclosure structure into several blocks along the layout of the circumferential water drill holes 32 and performs block cutting in the direction from top to bottom.

[0051] This invention utilizes a combination of circumferential and vertical water-drilled holes for wire saw cutting. Compared to existing technologies that distribute water-drilled holes at the four corners of each segment, this method not only completes segmented cutting but also significantly reduces the number of water-drilled holes, thereby reducing construction time and costs.

[0052] Combined with appendix Figure 5 In the specific implementation process, the second area of ​​the retaining structure 3 can be divided into blocks at a spacing of 2.5m x 1.5m. That is to say, the horizontal spacing of the circumferential water drill holes is 2.5m, while the vertical spacing of the circumferential water drill holes is 1.5m. Cutting lines 33 are drawn, and the wire saw cutting machine cuts the second area into 2.5m x 1.5m blocks along the cutting lines 33. When using the wire saw for cutting, the blocks are cut from top to bottom, and a method of cutting one block and hoisting it away is adopted to ensure the safety of construction.

[0053] In some embodiments, when breaking down the third region of the enclosure structure in step (2.2), before opening the plum blossom-shaped openings in the vertical direction, the upper surface of the third region is first cut to form an open surface, and then static expansion is carried out using the openings and the prepared expansion agent.

[0054] In some embodiments, when using an expanding agent to statically expand and break down the third region of the retaining structure, segmented breaking is employed. This involves segmented static expansion breaking along the length of the retaining structure to reduce the impact of compression on the main structure 1 and ensure the structural safety of the underground project. Furthermore, the main reinforcing bars 31 within the retaining structure are retained. During the pouring of the post-pouring strip 24 of the base slab, the main reinforcing bars 31 are connected to the reinforcing steel skeleton within the post-pouring strip, thereby forming a unified whole between the unbroken retaining structure and the post-pouring strip 24 of the base slab, fully utilizing the function of the unbroken retaining structure.

[0055] In existing technologies, the enclosure structure below the upper surface of the base plate is typically demolished using pneumatic drills due to space constraints. This method significantly impacts the main structure with vibrations. This invention utilizes an expanding agent for static expansion demolition, avoiding the vibration impact of pneumatic drills on the main structure. Furthermore, by optimizing the drilling site and employing a segmented demolition method, the impact on the main structure (its structural frame columns) is reduced, ensuring the structural safety of the main structure.

[0056] In summary, this invention employs different demolition methods for the retaining structure at different heights, which improves the demolition efficiency and reduces noise and dust pollution during the entire demolition process. More importantly, because it can quickly demolish the retaining structure at the shared wall between the main structure and the auxiliary structures, it can expedite the overall capping of the underground project, preventing groundwater from entering the underground project; at the same time, it eliminates the impact on the existing underground project (main structure and auxiliary structures).

[0057] It should be understood that the above description of the preferred embodiments is quite detailed, but it should not be considered as a limitation on the scope of protection of this invention. Those skilled in the art, under the guidance of this invention, can make substitutions or modifications without departing from the scope of protection of the claims of this invention, and all such substitutions or modifications fall within the scope of protection of this invention. The scope of protection of this invention should be determined by the appended claims.

Claims

1. A construction method for efficiently breaking down the retaining structure shared by the main body and auxiliary structures of an underground engineering project, characterized in that, include: (1) After the main construction of the underground project is completed, the auxiliary structure is constructed; when constructing the top and bottom slabs of the auxiliary structure, a reserved space is reserved between the top and bottom slabs of the auxiliary structure and the enclosure structure of the main project for the pouring of the post-pouring strip; (2) The enclosure structure at the point where the main structure and the ancillary structure share a wall shall be demolished, specifically including the following: (2.1) The enclosure structure is divided according to its height position. The enclosure structure above the upper surface of the top plate of the auxiliary structure is called the first area, the enclosure structure between the bottom plate and the top plate of the auxiliary structure is called the second area, and the enclosure structure below the upper surface of the bottom plate of the auxiliary structure is called the third area. The bottom end of the third area is spaced from the lower end of the bottom plate so as to expose part of the main reinforcement in the enclosure structure. (2.2) Static expansion is used to break up the first and third areas of the enclosure structure using an expansion agent, and wire saw is used to break up the second area of ​​the enclosure structure. During the process of breaking up the enclosure structure, the first, second and third areas are broken up in sequence.

2. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of underground engineering projects according to claim 1, characterized in that, After the enclosure structure is demolished, post-cast strips are poured in the spaces reserved in the bottom and top slabs of the auxiliary structure so that the bottom and top slabs of the auxiliary structure are connected to the structural frame columns of the main project. When pouring the post-cast strips at the bottom slab of the auxiliary structure, the main reinforcement bars after the third area of ​​the enclosure structure is demolished are anchored into the bottom slab so that the enclosure structure below the bottom slab that has not been demolished forms an integral whole with the bottom slab.

3. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of underground engineering projects according to claim 1, characterized in that, When breaking down the first and third areas of the enclosure structure in step (2.2), first drill vertically downwards to form plum blossom-shaped holes, and put the prepared expansion agent into the holes. The plum blossom-shaped holes include a row of holes close to the structural frame columns of the main project and arranged along the length of the enclosure structure, and other rows of holes further away from the structural frame columns of the main project. The distance between the quadrant point of the structural frame column closer to the main project in the row of holes and the outer side of the structural frame column close to the main project on the enclosure structure is X. X is less than the radius R of the hole and greater than half of the radius R of the hole.

4. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of underground engineering projects according to claim 3, characterized in that, When statically expanding and breaking the first area of ​​the enclosure structure with an expanding agent, segmented breaking is adopted. During segmented breaking, pre-cracks or pre-slits are opened on the exposed side of the enclosure structure. The positions of the pre-cracks or pre-slits correspond to the positions of the upper surface of the top plate.

5. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of underground engineering projects according to claim 1, characterized in that, When breaking down the second area of ​​the enclosure structure in step (2.2), circumferential water drill holes are evenly opened around the perimeter of the second area, and a row of vertical water drill holes is opened in the middle of the length direction of the second area of ​​the enclosure structure. The wire saw cutting machine divides the second area of ​​the enclosure structure into several blocks along the layout of the circumferential water drill holes and cuts them in blocks from top to bottom.

6. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of underground engineering projects according to claim 5, characterized in that, When breaking down the third area of ​​the enclosure structure in step (2.2), before opening the plum blossom-shaped holes vertically, the upper surface of the third area is first cut to form an open surface, and then static expansion is carried out using the holes and the prepared expansion agent.

7. The construction method for efficiently demolishing the retaining structure shared by the main body and auxiliary structures of an underground engineering project according to claim 6, characterized in that, When using an expansion agent to statically expand and break down the third zone of the enclosure structure, segmented breaking is adopted, while retaining the main reinforcement bars within the enclosure structure.

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