Green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports

Abstract

The present invention relates to the technical field of deep and large foundation pit excavation, and discloses a green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports, comprising the following construction steps: 1) constructing a retaining pile structure, and driving a plurality of core piles into the middle of the foundation pit; 2) excavating a soil body of a set depth in the foundation pit; 3) forming a side groove, and constructing a waist beam in the side groove; 4) splicing assembled longitudinal beams with core piles, with an assembly interval between the core piles and the waist beam; 5) arranging assembled composite plates, and the retaining piles, waist beams, composite plates, core piles and longitudinal beams form an integrated assembled internal support; 6) repeating construction steps 3) to 5) until the foundation pit is excavated to the bottom of the foundation pit; avoiding the removal of traditional cast-in-place internal supports, thereby significantly reducing construction waste and resource waste, reducing construction safety risks and improving construction efficiency, and promoting sustainable, mechanized and high-quality earthwork excavation transformation and the establishment of a waste-free city.

Description

Technical Field

[0001] The patent of this invention relates to the technical field of deep and large foundation pit excavation methods, specifically, to a green and low-carbon excavation method for deep and large foundation pits based on prefabricated internal supports. Background Art

[0002] At present, deep and large foundation pit excavation mostly uses bored cast-in-place piles as retaining structures, and uses steel supports or concrete supports to form internal supports. Among them, the retaining structure is prone to problems such as exposed reinforcement and honeycomb surface, which will cause quality and safety risks; secondly, the internal support needs to be removed later, which is difficult to remove and has high risks of high-altitude operations, high construction risks, high resource waste rate, and low construction efficiency.

[0003] In addition, in order to facilitate the transportation of the bottom layer of earth and affected by the internal supports at both ends of the foundation pit, the earth transportation road is usually set in the middle of the long side of the foundation pit, and a large number of steel supports or concrete supports are cancelled to facilitate the movement of earth transport vehicles. This location is exactly in the bending weak zone of the foundation pit retaining structure, which greatly increases the risk of foundation pit collapse. Summary of the invention

[0004] The purpose of the present invention is to provide a deep and large foundation pit excavation method based on an assembled composite structure system as an internal support, aiming to solve the problems of high resource waste rate and low construction efficiency in deep and large foundation pit excavation in the prior art.

[0005] The present invention is implemented in this way: a green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports comprises the following construction steps:

[0006] 1) According to the scope of foundation pit excavation, a closed and assembled retaining pile structure is constructed on the periphery of the foundation pit, and the retaining pile structure is closed and surrounded along the periphery of the foundation pit; a plurality of assembled and spaced core piles are driven into the middle of the foundation pit, and the retaining pile structure and the core piles penetrate the soil layer and are embedded in the hard rock layer;

[0007] 2) The foundation pit is in a rectangular shape, having two oppositely arranged long sides and two oppositely arranged short sides, and a soil body of a set depth is excavated in the foundation pit;

[0008] 3) Excavating soil of a set depth on the two long sides of the foundation pit to form side grooves, and the side grooves are arranged along the length direction of the long sides; constructing a waist beam in the side grooves, and the waist beam is connected to the retaining pile structure;

[0009] 4) Excavate the soil between the two side grooves to form a hollow area, and hoist the assembled longitudinal beam in the hollow area. The longitudinal beam is spliced ​​with the core pile, and there is a mounting interval between the core pile and the waist beam;

[0010] 5) Arrange assembled composite plates in the erection interval, the retaining pile structure, waist beam, composite plates, core piles and longitudinal beams form an integrated assembled inner support, and continue to excavate the soil to a set depth downward;

[0011] 6) Repeat construction steps 3) to 5) until the foundation pit is excavated to the bottom of the foundation pit.

[0012] Furthermore, in the construction step 1), the foundation pit is laid out and measured to determine the excavation range of the foundation pit.

[0013] Furthermore, in the construction step 1), multiple assembly pile holes arranged at intervals are drilled outside the foundation pit, and the multiple assembly pile holes are arranged around the outer circumference of the foundation pit at intervals, and the assembly pile holes pass through the soil layer and extend into the hard rock layer; assembled square piles are driven into the assembly pile holes, and there is a pile interval between adjacent square piles;

[0014] Jet-jet piles are constructed in the pile intervals, and the jet-jet piles are integrated with the square piles to form the retaining pile structure.

[0015] Furthermore, in the construction step 1), after the square pile is driven into the assembly pile hole, the assembly pile hole is filled with concrete to form a concrete layer wrapped around the outer periphery of the square pile, and the jet-jet pile is combined with the concrete layer to form a whole.

[0016] Furthermore, in the construction step 3), transverse steel bars are provided in the waist beam, the transverse steel bars are implanted in the square piles and integrated with the square piles, and the transverse steel bars extend out of the top of the waist beam to form transverse reserved steel bars.

[0017] Furthermore, in the construction step 4), both sides of the longitudinal beam extend outward to form a receiving platform, and the longitudinal beam is provided with longitudinal steel bars, which are implanted in the core piles and integrated with the core piles; the longitudinal steel bars extend out of the top of the receiving platform to form longitudinal reserved steel bars.

[0018] Furthermore, in the construction step 7), plate reserved steel bars are respectively extended from both ends of the composite plate, one end of the composite plate abuts on the waist beam, the plate reserved steel bars at one end of the composite plate are fixedly connected to the transverse reserved steel bars, the other end of the composite plate abuts on the receiving platform, and the plate reserved steel bars at the other end of the composite plate are fixedly connected to the longitudinal reserved steel bars.

[0019] Furthermore, an inclined plate is arranged in the foundation pit and is used by a soil transport vehicle to transport soil. The upper end of the inclined plate is butted against the retaining pile structure and extends to the ground, and the lower end of the inclined plate is butted against the soil.

[0020] The inclined plate and the retaining pile structure enclose a support area, in which an inclined outer steel pipe is provided. The lower end of the outer steel pipe is butted against the retaining pile structure, and the upper end of the outer steel pipe is butted against the middle of the inclined plate.

[0021] Furthermore, a steel plate is provided in the middle of the inclined plate and on the retaining pile structure, and an outer tube hole is provided inside the outer steel tube, and the outer tube hole passes through the two ends of the outer steel tube respectively to form an outer end opening; the middle of the outer tube hole is concave outward to form a positioning groove arranged in an annular manner, and the positioning groove is arranged around the circumference of the outer tube hole;

[0022] A movable elastic disk is embedded in the positioning groove, and an outer annular space is provided between the outer periphery of the elastic disk and the outer periphery of the positioning groove; two inner steel tubes are sleeved in the outer steel tube, the inner ends of the inner steel tubes are fixedly docked with the elastic disk, and the outer ends of the inner steel tubes extend out of the outer end opening;

[0023] When the two ends of the outer steel pipe are fixedly docked on the two steel plates respectively, the outer end of the inner steel pipe is movably docked on the steel plate, the inner steel pipe is pressed to move toward the inside of the outer steel pipe, and the elastic disk is compressed and deformed toward the outer annular interval until the outer periphery of the elastic disk abuts against the outer periphery of the positioning groove.

[0024] Furthermore, elastic columns are respectively extended on both sides of the elastic disk, and an inner tube hole is provided in the inner steel tube, and the inner tube hole penetrates both ends of the inner steel tube to form an inner end opening; the elastic column is inserted into the inner tube hole and extends out of the inner end opening, and an inner annular gap is provided between the outer periphery of the elastic column and the inner side wall of the inner tube hole;

[0025] When the two ends of the outer steel tube are fixedly docked on two steel plates respectively, the end of the elastic column abuts on the steel plate, and the elastic column is compressed and moves toward the inner tube hole until the outer periphery of the elastic column abuts on the inner wall of the inner tube hole.

[0026] Compared with the prior art, the green and low-carbon excavation method for deep and large foundation pits based on prefabricated internal supports provided by the present invention utilizes a retaining pile structure as the peripheral support of the foundation pit, and forms an integrated prefabricated internal support through prefabricated composite plates, retaining pile structures, waist beams, composite plates, core piles and longitudinal beams, thereby reducing quality problems caused by cast-in-place construction. Secondly, during the subsequent demolition of the internal support, concrete can be avoided from being chiseled out, thereby reducing construction risks, reducing resource waste and improving construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the process of the green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports provided by the present invention;

[0028] Figure 2It is a schematic diagram of the construction structure of the green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports provided by the present invention;

[0029] Figure 3 It is a top view schematic diagram of the foundation pit retaining pile structure provided by the present invention;

[0030] Figure 4 It is a top view schematic diagram of the side trench of the foundation pit excavation provided by the present invention;

[0031] Figure 5 is a front view schematic diagram of a longitudinal beam provided by the present invention;

[0032] Figure 6 It is a front view schematic diagram of the cooperation between the inclined plate and the outer steel pipe provided by the present invention;

[0033] Figure 7 It is a cross-sectional schematic diagram of the outer steel pipe and the inner steel pipe provided by the present invention in an unsupported state;

[0034] Figure 8 It is a cross-sectional schematic diagram of the outer steel pipe and the inner steel pipe provided by the present invention in a supporting state. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] The implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0037] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] Reference Figure 1-8 The figure shows a preferred embodiment of the present invention.

[0039] The green and low-carbon excavation method for deep and large foundation pits based on prefabricated internal supports includes the following construction steps:

[0040] 1) According to the excavation range of the foundation pit 200, a closed and assembled retaining pile structure 100 is constructed on the periphery of the foundation pit 200, and the retaining pile structure 100 is closed and surrounded along the periphery of the foundation pit 200; a plurality of assembled and spaced core piles 303 are driven into the middle of the foundation pit 200, and the retaining pile structure 100 and the core piles 303 penetrate into the soil layer and are embedded in the hard rock layer;

[0041] The above-mentioned retaining pile structure 100 is arranged in a closed manner to form a continuous water-stopping curtain, which can form an enclosure support for the outer periphery of the foundation pit 200.

[0042] 2) The foundation pit 200 is in a rectangular shape, and has two oppositely arranged long sides 201 and two oppositely arranged short sides 202. A soil body of a set depth is excavated in the foundation pit 200;

[0043] 3) Excavate soil of a set depth on the two long sides 201 of the foundation pit 200 to form side grooves 203, which are arranged along the length direction of the long sides 201; construct a waist beam 301 in the side groove 203, and the waist beam 301 is connected to the retaining pile structure 100;

[0044] By forming the side groove 203, the working space of the cast-in-place waist beam 301 is ensured, and the excavation speed is ensured at the same time; in addition, no less than two earthwork excavation machines can be used to excavate the earthwork along the long side 201 of the foundation pit 200 and close to the retaining pile structure 100, and the excavation width is preferably 3-5 meters;

[0045] 4) Excavate the soil between the two side grooves 203 to form a hollow area, hoist the assembled longitudinal beam 304 in the hollow area, splice the longitudinal beam 304 with the core pile 303, and there is a mounting interval between the core pile 303 and the waist beam 301; after the concrete strength of the waist beam 301 reaches the requirement, use multiple earthwork excavation machines to uniformly excavate from one short side 202 of the foundation pit 200 toward the other short side 202 in parallel;

[0046] 5) Arrange the assembled composite plate 302 in the assembly interval, the retaining pile structure 100, the waist beam 301, the composite plate 302, the core pile 303 and the longitudinal beam 304 to form an integrated assembled inner support 300, and continue to excavate the soil to a set depth downward;

[0047] 6) Repeat construction steps 3) to 5) until the foundation pit 200 is excavated to the bottom of the foundation pit 200.

[0048] The green and low-carbon excavation method for deep and large foundation pits based on prefabricated internal supports provided above utilizes the retaining pile structure 100 as the peripheral support of the foundation pit 200, and forms an integrated prefabricated internal support 300 through the prefabricated composite plate 302, the retaining pile structure 100, the waist beam 301, the composite plate 302, the core pile 303 and the longitudinal beam 304, thereby reducing the quality problems caused by cast-in-place. Secondly, during the subsequent demolition process of the internal support 300, the concrete can be avoided from being chiseled off, thereby reducing the construction risk and improving the construction efficiency.

[0049] In this embodiment, the assembled components can be prefabricated components, that is, they are prefabricated according to the size of the deep and large foundation pit. The prefabricated components are innovatively assembled as internal supports for earth excavation, which realizes the simultaneous development of earth excavation and assembled construction, avoids the removal of traditional cast-in-place internal supports, and thus significantly reduces construction waste, resource waste, reduces construction safety risks, and improves construction efficiency, promotes the transformation of sustainable, mechanized and high-quality earth excavation and the establishment of a waste-free city, and embodies the characteristics of green and low-carbon construction.

[0050] In this embodiment, in construction step 1), the foundation pit 200 is laid out and measured to determine the excavation range of the foundation pit 200.

[0051] In this embodiment, in the construction step 1), a plurality of assembly pile holes arranged at intervals are drilled outside the foundation pit 200, and the plurality of assembly pile holes are arranged around the periphery of the foundation pit 200 at intervals, and the assembly pile holes pass through the soil layer and extend into the hard rock layer;

[0052] The assembled square piles 101 are driven into the assembled pile holes, with pile gaps between adjacent square piles 101; the jet grouting piles 102 are constructed in the pile gaps, and the jet grouting piles 102 are integrated with the square piles 101 to form the above-mentioned retaining pile structure 100.

[0053] In the process of forming the assembly pile hole, a large-diameter long spiral high-efficiency drilling machine is used to drill holes in the soil layer, and a cluster pneumatic down-the-hole hammer drilling machine is used to drill holes in the hard rock layer. In addition, arranging assembled square piles 101 in the assembly pile hole can greatly reduce the quality problems caused by cast-in-place and improve the utilization efficiency of underground space.

[0054] In this embodiment, in construction step 1), after the square pile 101 is driven into the assembly pile hole, concrete is filled in the assembly pile hole to form a concrete layer wrapped around the outer periphery of the square pile 101, and the jet-jet pile 102 is integrated with the concrete layer.

[0055] In this embodiment, in construction step 3), transverse steel bars are provided in the waist beam 301, the transverse steel bars are implanted in the square piles 101, and are integrated with the square piles 101, and the transverse steel bars extend out of the top of the waist beam 301 to form transverse reserved steel bars.

[0056] The transverse reinforcement of the waist beam 301 is connected with the assembled square piles 101 through embedded reinforcement. During the construction of the waist beam 301, after the transverse reinforcement is tied, the concrete can be cast in situ to form the waist beam 301. The transverse reserved reinforcement formed by the extension of the transverse reinforcement does not need to be cast in situ, but is used for later splicing with the assembled composite plate 302.

[0057] In this embodiment, in construction step 4), both sides of the longitudinal beam 304 extend outwards to form a receiving platform 3041. The longitudinal beam 304 has longitudinal steel bars, which are implanted in the core pile 303 and integrated with the core pile 303. The longitudinal steel bars extend out of the top of the receiving platform 3041 to form longitudinal reserved steel bars. The arrangement of the longitudinal reserved steel bars facilitates the later splicing with the assembled composite plate 302, so as to cast the whole.

[0058] In this embodiment, in construction step 7), reserved plate steel bars are extended from both ends of the composite plate 302 respectively, one end of the composite plate 302 abuts against the waist beam 301, the reserved plate steel bars at one end of the composite plate 302 are fixedly connected to the transverse reserved steel bars, the other end of the composite plate 302 abuts against the receiving platform 3041, and the reserved plate steel bars at the other end of the composite plate 302 are fixedly connected to the longitudinal reserved steel bars.

[0059] In this way, the reserved steel bars at both ends of the composite plate 302 are respectively fixedly connected to the transverse reserved steel bars and the longitudinal reserved steel bars, so that the formed inner support 300 forms an integrated structure.

[0060] In this embodiment, an inclined plate 400 is arranged in the foundation pit 200 for earth transport trucks to transport earth. The upper end of the inclined plate 400 is connected to the retaining pile structure 100 and extends to the ground, and the lower end of the inclined plate 400 is connected to the soil. The inclined plate 400 and the retaining pile structure 100 form a support area 401, and an outer steel pipe 402 is arranged in an inclined manner in the support area 401. The lower end of the outer steel pipe 402 is connected to the retaining pile structure 100, and the upper end of the outer steel pipe 402 is connected to the middle of the inclined plate 400.

[0061] As the excavation depth increases, the above-mentioned inclined plate 400 is set up in the reserved earthwork transportation space to form an earthwork transportation channel, avoiding the disadvantage that the earthwork transportation channel is set at the weakest bending position of the foundation pit 200 under the previous concrete support.

[0062] The inclined plate 400 can be constructed by using prefabricated concrete plates or cast-in-place concrete to ensure that the inclined plate 400 has a certain bearing capacity and is easy to dismantle later.

[0063] In this embodiment, a steel plate 403 is provided in the middle of the inclined plate 400 and on the retaining pile structure 100, respectively. An outer tube hole is provided inside the outer steel tube 402, and the outer tube hole passes through both ends of the outer steel tube 402 to form an outer end opening; the middle of the outer tube hole is concave outward to form a ring-shaped positioning groove, and the positioning groove is arranged around the circumference of the outer tube hole;

[0064] A movable elastic disk 503 is embedded in the positioning groove, and an outer annular spacer 502 is provided between the outer periphery of the elastic disk 503 and the outer periphery of the positioning groove; two inner steel tubes 500 are sleeved in the outer steel tube 402, and the inner ends of the inner steel tubes 500 are fixedly docked with the elastic disk 503, and the outer ends of the inner steel tubes 500 extend out of the outer end opening;

[0065] When the two ends of the outer steel tube 402 are fixedly docked on the two steel plates 403 respectively, the outer end of the inner steel tube 500 is movably docked on the steel plate 403, and the inner steel tube 500 is pressed to move toward the inside of the outer steel tube 402, and the elastic disk 503 is compressed and deformed toward the outer annular spacer 502, until the outer periphery of the elastic disk 503 abuts against the outer periphery of the positioning groove.

[0066] In this way, the elastic disk 503 is in a compressive deformation state, which applies reverse pressure to the inner steel tube 500, so that the inner steel tube 500 is firmly abutted against the steel plate 403, and the inner steel tube 500 and the outer steel tube 402 form a double-layer abutment with the steel plate 403, which greatly improves the supporting strength. The elastic deformation of the elastic disk 503 can be used to adjust the abutment position of the inner steel tube 500, and it can also play a shock-absorbing role.

[0067] In this embodiment, elastic columns 504 extend from both sides of the elastic disk 503, and the inner steel tube 500 has an inner tube hole, which passes through both ends of the inner steel tube 500 to form an inner end opening; the elastic column 504 is inserted into the inner tube hole and extends out of the inner end opening, and an inner annular spacer 501 is provided between the outer periphery of the elastic column 504 and the inner side wall of the inner tube hole;

[0068] When the two ends of the outer steel tube 402 are fixedly docked on the two steel plates 403 respectively, the end of the elastic column 504 abuts against the steel plate 403, and the elastic column 504 is compressed and moves toward the inner tube hole until the outer periphery of the elastic column 504 abuts against the inner wall of the inner tube hole.

[0069] By arranging to form an elastic column 504, the elastic column 504 is in compression deformation and abuts against the steel plate 403, thereby improving the support strength, and the elastic column 504 is in elastic support, which can play a shock-absorbing role. In this way, the outer steel tube 402, the inner steel tube 500, the elastic disk 503 and the elastic column 504 form multi-position abutment with the steel plate 403, and multi-layer elastic abutment can be achieved, which can enhance the support strength and achieve shock absorption.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports, characterized in that: The construction steps include: 1) According to the scope of foundation pit excavation, a closed and assembled retaining pile structure is constructed on the periphery of the foundation pit, and the retaining pile structure is closed and surrounded along the periphery of the foundation pit; a plurality of assembled and spaced core piles are driven into the middle of the foundation pit, and the retaining pile structure and the core piles penetrate the soil layer and are embedded in the hard rock layer; 2) The foundation pit is in a rectangular shape, having two oppositely arranged long sides and two oppositely arranged short sides, and a soil body of a set depth is excavated in the foundation pit; 3) Excavating soil of a set depth on the two long sides of the foundation pit to form side grooves, and the side grooves are arranged along the length direction of the long sides; constructing a waist beam in the side grooves, and the waist beam is connected to the retaining pile structure; 4) Excavate the soil between the two side grooves to form a hollow area, and hoist the assembled longitudinal beam in the hollow area. The longitudinal beam is spliced ​​with the core pile, and there is a mounting interval between the core pile and the waist beam; 5) Arrange assembled composite plates in the erection interval, the retaining pile structure, waist beam, composite plates, core piles and longitudinal beams form an integrated assembled inner support, and continue to excavate the soil to a set depth downward; 6) Repeat construction steps 3) to 5) until the foundation pit is excavated to the bottom of the foundation pit.

2. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 1 is characterized in that: In the construction step 1), the foundation pit is laid out and measured to determine the excavation range of the foundation pit.

3. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 1 is characterized in that: In the construction step 1), multiple assembly pile holes are drilled outside the foundation pit to form a plurality of assembly pile holes arranged at intervals, the plurality of assembly pile holes are arranged around the outer circumference of the foundation pit at intervals, the assembly pile holes pass through the soil layer and extend into the hard rock layer; assembled square piles are driven into the assembly pile holes, with pile intervals between adjacent square piles; Jet-jet piles are constructed in the pile intervals, and the jet-jet piles are integrated with the square piles to form the retaining pile structure.

4. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 3 is characterized in that: In the construction step 1), after the square pile is driven into the assembly pile hole, the assembly pile hole is filled with concrete to form a concrete layer wrapped around the outer periphery of the square pile, and the jet-jet pile is integrated with the concrete layer.

5. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 3 is characterized in that: In the construction step 3), transverse steel bars are provided in the waist beam, the transverse steel bars are implanted in the square piles and integrated with the square piles, and the transverse steel bars extend out of the top of the waist beam to form transverse reserved steel bars.

6. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 5 is characterized in that: In the construction step 4), both sides of the longitudinal beam extend outward to form a receiving platform, and the longitudinal beam has longitudinal steel bars, which are implanted in the core piles and integrated with the core piles; the longitudinal steel bars extend out of the top of the receiving platform to form longitudinal reserved steel bars.

7. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 6 is characterized in that: In the construction step 7), reserved plate steel bars are respectively extended from both ends of the composite plate, one end of the composite plate abuts on the waist beam, the reserved plate steel bars at one end of the composite plate are fixedly connected to the transverse reserved steel bars, the other end of the composite plate abuts on the receiving platform, and the reserved plate steel bars at the other end of the composite plate are fixedly connected to the longitudinal reserved steel bars.

8. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports according to any one of claims 1 to 7, characterized in that: An inclined plate is arranged in the foundation pit and is used by a soil transport vehicle to transport soil. The upper end of the inclined plate is butted against the retaining pile structure and extends to the ground, and the lower end of the inclined plate is butted against the soil. The inclined plate and the retaining pile structure enclose a support area, in which an inclined outer steel pipe is provided. The lower end of the outer steel pipe is butted against the retaining pile structure, and the upper end of the outer steel pipe is butted against the middle of the inclined plate.

9. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports as claimed in claim 8, characterized in that: A steel plate is provided in the middle of the inclined plate and on the retaining pile structure, respectively; an outer tube hole is provided inside the outer steel tube, and the outer tube hole passes through both ends of the outer steel tube to form an outer end opening; the middle of the outer tube hole is concave outward to form a ring-shaped positioning groove, and the positioning groove is arranged around the circumference of the outer tube hole; A movable elastic disk is embedded in the positioning groove, and an outer annular space is provided between the outer periphery of the elastic disk and the outer periphery of the positioning groove; two inner steel tubes are sleeved in the outer steel tube, the inner ends of the inner steel tubes are fixedly docked with the elastic disk, and the outer ends of the inner steel tubes extend out of the outer end opening; When the two ends of the outer steel pipe are fixedly docked on the two steel plates respectively, the outer end of the inner steel pipe is movably docked on the steel plate, the inner steel pipe is pressed to move toward the inside of the outer steel pipe, and the elastic disk is compressed and deformed toward the outer annular interval until the outer periphery of the elastic disk abuts against the outer periphery of the positioning groove.

10. The green and low-carbon excavation method for deep and large foundation pits based on assembled internal supports according to claim 9, characterized in that: Elastic columns extend from both sides of the elastic disk, and an inner tube hole is provided in the inner steel tube, and the inner tube hole penetrates both ends of the inner steel tube to form an inner end opening; the elastic column is inserted into the inner tube hole and extends out of the inner end opening, and an inner annular space is provided between the outer periphery of the elastic column and the inner side wall of the inner tube hole; When the two ends of the outer steel tube are fixedly docked on two steel plates respectively, the end of the elastic column abuts on the steel plate, and the elastic column is compressed and moves toward the inner tube hole until the outer periphery of the elastic column abuts on the inner wall of the inner tube hole.

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