Support system and method combining temporary foundation pit support and permanent slope support

Abstract

The present invention belongs to the field of geotechnical engineering technology, and discloses a support system and method combining temporary foundation pit support and permanent slope support, wherein a temporary support pile top crown beam is arranged on the top of the temporary support pile, a permanent support structure pile is arranged on one side of the temporary support pile, a permanent support structure pile top crown beam is arranged on the upper end of the permanent support structure pile, and a permanent surface wall is arranged on the upper end of the permanent support structure pile top crown beam; a permanent cover plate is arranged on the upper end of the permanent surface wall and the upper end of the permanent rib wall; the permanent surface wall and the left side of the permanent support structure pile top crown beam are connected to the basement side wall through a concrete slab, and permanent support rib walls are arranged at regular intervals between the temporary support pile and the permanent support surface wall along the foundation pit edge line. The present invention satisfies the combination of temporary foundation pit support and permanent slope support, and the purpose of greening the environment and improving the ecological environment can be achieved by setting a vegetation hanging net through a reserved connection piece in the permanent surface wall above the basement.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a support system and method combining temporary foundation pit support and permanent slope support. Background Art

[0002] At present, with the emergence of a large number of high-rise, super-high-rise and underground buildings in my country, foundation pit projects have gradually shown the characteristics of wide range, great depth and complex environment. Especially in some areas, when the current ground elevation is much higher than the design elevation of the basement top plate, temporary foundation pit support is required to ensure the smooth excavation of the foundation pit, and permanent slope support is required for the high slope surface above the basement top plate elevation that appears after the foundation pit excavation. The current common practice is to adopt temporary support measures for temporary foundation pits, and then do permanent slope support after the construction of the basement and the main structure. The commonly used support forms of permanent slope support are permanent anchor cables, rubble concrete retaining walls, gravity retaining walls, etc.

[0003] For projects that require both temporary foundation pit support and permanent slope support for the high slope surface above the basement that appears during the excavation of the foundation pit, the current common practice is to use temporary support measures for the temporary foundation pit, and then do permanent slope support after the construction of the basement and the main structure. Temporary foundation pit support measures and permanent slope support measures are often separated, resulting in a long construction period. In addition, permanent slope support usually adopts permanent anchor cables, rubble concrete retaining walls, gravity retaining walls, etc. However, permanent anchor cable support has great limitations. For example, in an environment close to the sea that is susceptible to seawater corrosion, the reliability and durability of permanent anchor cables are often insufficient, or when there are sensitive buildings outside the foundation pit, anchor cables are often unable to be constructed. Rubble concrete retaining walls and gravity retaining walls often have large deformations when the slope is greater than 10m, which does not meet the requirements of the corresponding national specifications. The normal service life of a permanent slope is generally not less than 50 years. Once the slope safety reserve is insufficient, the slope will suffer from adverse geological disasters such as collapse and landslides. Moreover, the slope support adopts simple masonry support structures such as concrete retaining walls, which cannot be greened and does not meet the green ecological requirements.

[0004] Through the above analysis, the problems and defects of the existing technology are: temporary foundation pits adopt temporary support measures, and permanent slope support is carried out after the basement and main structure are constructed. Temporary foundation pit support measures and permanent slope support measures are often separated, which makes the construction period longer.

[0005] Permanent anchor support has great limitations. For example, in an environment close to the sea that is susceptible to seawater corrosion, the reliability and durability of permanent anchors are often insufficient, or when there are sensitive buildings outside the foundation pit, anchor construction is often impossible.

[0006] When the slope is greater than 10m, the deformation of rubble concrete retaining walls and gravity retaining walls is often large and does not meet the requirements of relevant national standards.

[0007] Once the permanent slope safety reserve is insufficient, the slope will suffer from adverse geological disasters such as collapse and landslide; and the slope support adopts simple masonry support structures such as concrete retaining walls, which cannot be greened and does not meet the green ecological requirements.

[0008] The difficulty of solving the above problems and defects is: how to provide a new combined support structure to make full use of the temporary support structure that has been constructed, which is convenient and easy to construct, safe and reliable, and green and environmentally friendly.

[0009] The significance of solving the above problems and defects is: in order to solve the situation that the current temporary foundation pit support and permanent slope support construction measures are separated and the current commonly used permanent slope support forms are limited in use or cannot be greened, the present invention creates a green combined support structure combining temporary foundation pit support and permanent slope support. The structure can be suitable for slope projects with deep foundation pit excavation, clay layer or rock layer exposed at the bottom of the pit, and a height difference of 10 to 25m between the pit top and the basement roof. In the case of high slopes above the basement that need permanent support, the constructed temporary support structure can be fully utilized, which is convenient and easy to construct, safe and reliable, and greening and environmentally friendly. Summary of the invention

[0010] In order to solve the problems existing in the prior art, the present invention provides a support system and method combining temporary foundation pit support and permanent slope support.

[0011] The present invention is implemented in that a support system combining temporary foundation pit support and permanent slope support is provided with: temporary support piles;

[0012] A temporary support pile top crown beam is arranged on the top of the temporary support pile, a permanent support structure pile is arranged on one side of the temporary support pile, a permanent support structure pile top crown beam is arranged on the upper end of the permanent support structure pile, and a permanent surface wall is arranged on the upper end of the permanent support structure pile top crown beam; the permanent cover plate is arranged on the upper end of the permanent surface wall and the upper end of the permanent rib wall;

[0013] The permanent surface wall and the left side of the permanent support structure pile top crown beam are connected to the basement side wall through a concrete slab, and permanent support rib walls are arranged at regular intervals along the foundation pit edge between the temporary support piles and the permanent support surface wall;

[0014] A permanent support structure bottom plate is arranged at the bottom between the top crown beam of the permanent support structure pile and the temporary support pile, a permanent support structure ground beam is arranged on the upper side of the permanent support structure bottom plate, and a permanent support rib wall is arranged on the upper side of the permanent support structure ground beam; backfill soil layers are arranged between the permanent support structure bottom plate and the permanent middle plate, and between the permanent middle plates.

[0015] Furthermore, a permanent rib wall is provided between the temporary support piles and the permanent surface wall;

[0016] The top crown beam of the temporary supporting pile is connected to the upper end of the permanent cover plate.

[0017] Furthermore, a backfill soil layer is provided between the two concrete slabs.

[0018] Furthermore, connecting pieces are reserved on the permanent surface wall above the basement, and vegetation hanging nets are arranged on the reserved connecting pieces.

[0019] Furthermore, the cross section of the temporary support pile is circular, and the pile diameter is determined according to the specific situation, which is 0.6 to 1.2 m, directly resisting the soil pressure;

[0020] A temporary support pile crown beam is arranged on the top of the temporary support pile, and a permanent support structure pile is arranged on one side of the temporary support pile. The cross-section of the permanent support structure pile is circular, the pile diameter is 0.6-1.2m, the pile length is 10-15m to enter the 3 clay layers at the bottom of the pit or 5-10m to enter the rock layer, and the pile spacing is the spacing between the permanent rib walls 12; the permanent support structure pile, as a load-bearing component, bears the dead weight of the permanent face wall, and plays the role of a fixed end by entering the clay layer 10-15m or the rock layer 5-10m at the bottom of the pit to ensure the lateral displacement resistance of the permanent face wall.

[0021] Furthermore, a permanent support structure pile top crown beam is provided at the upper end of the permanent support structure pile, the cross section of the permanent support structure pile top crown beam is square, the width b8=d4+0.2m, d4 is the pile diameter of the permanent support structure pile, the height h8 is taken as 0.8-1.0m, b is the width symbol, and h is the height symbol; as a force transmission layer, the permanent support structure pile top crown beam transmits the deadweight of the permanent face wall to the permanent support structure pile, and at the same time, the permanent face wall, the crown beam and the permanent support structure pile are tightly connected together through the steel bar anchoring action;

[0022] A permanent face wall is arranged at the upper end of the crown beam of the pile top of the permanent support structure, which plays the role of a flange in the combined retaining member of the permanent face wall, permanent rib wall and temporary support pile with an approximate I-shaped cross section; the permanent cover plate is arranged at the upper end of the permanent face wall and the upper end of the permanent rib wall, connecting the top of the permanent face wall, the top of the permanent rib wall and the crown beam of the temporary support pile top, connecting the top of the permanent face wall, the top of the permanent rib wall and the crown beam of the temporary support pile top together, thereby enhancing the integrity of the combined support structure;

[0023] The permanent facing wall and the left side of the permanent supporting structure pile top crown beam are connected to the basement side wall through a concrete slab. The lower end of the left side of the basement side wall is the basement floor slab, and the upper end of the left side of the basement side wall is the basement top slab. Permanent supporting rib walls are set at certain intervals along the edge of the foundation pit between the temporary support piles and the permanent supporting facing wall.

[0024] Furthermore, a permanent support structure bottom plate is provided at the bottom between the permanent support structure pile top crown beam and the temporary support pile, which can bear the weight from the permanent rib wall and the permanent support structure ground beam and evenly transfer it to the foundation;

[0025] A permanent support structure ground beam is arranged on the upper side of the permanent support structure bottom plate to transfer the weight of the upper permanent rib wall to the structure bottom plate; a permanent middle plate is arranged on the upper side of the permanent support structure ground beam, and a permanent rib wall is arranged on the permanent support ground beam. The permanent rib wall is a vertical component arranged at a certain distance along the pit edge, and the permanent middle plate is a horizontal component arranged between the permanent face wall and the temporary support piles at the same elevation as the concrete slab;

[0026] The permanent rib wall, permanent face wall and temporary support piles are connected horizontally to enhance the integrity of the composite support structure. The permanent middle plate has the same elevation as the concrete plate and basement floor, and the slope soil pressure is transmitted to the basement floor, forming a close connection between the basement structure and the composite support structure. The part of the composite support structure within the basement height range is the fixed end, and the part above the basement top plate elevation is the cantilever section.

[0027] Furthermore, a permanent rib wall is arranged between the temporary support piles and the permanent face wall, and is connected with the existing temporary support piles by planting reinforcement bars to form a combined retaining member with an approximately I-shaped cross-section of the permanent face wall, the permanent rib wall, and the temporary support piles, and the permanent rib wall plays the role of a web;

[0028] The crown beam on the top of the temporary support pile is connected to the upper end of the permanent cover plate;

[0029] Backfill soil layers are set between the permanent support structure bottom plate and the permanent middle plate, and between the permanent middle plates to evenly transfer the slope soil pressure to the basement floor;

[0030] A reserved connector is set on the left side of the permanent surface wall. When constructing the permanent surface wall above the basement, steel nails or short steel bar connectors are reserved at a certain distance. One end of the connector goes deep into the permanent surface wall, and the other end extends 10 to 30 cm outside the surface wall. The vegetation hanging net is fixed, stretched and spread on the permanent surface wall, and fixed through the reserved connector as the basis for the growth of green plants;

[0031] The thickness of the concrete slab is 0.7m; the thickness of the bottom slab and the permanent middle slab of the permanent supporting structure is 0.5m; the width of the permanent rib wall is 0.6-0.8m, and the wall height is the distance from the bottom to the top of the pit; the cross-section of the ground beam of the permanent supporting structure is square with a width of 0.8m-1.0m; the width of the permanent face wall is 0.8-1.0m, and the wall height is the distance from the bottom to the top of the pit; the thickness of the permanent cover plate h15 is 0.8m-1.0m;

[0032] The thickness of the concrete slab is 0.7m; the thickness of the bottom plate and the permanent middle plate of the permanent supporting structure are both 0.5m; the width of the permanent rib wall is 0.6~0.8m, and the wall height is the distance from the bottom of the pit to the top of the pit; the cross-section of the ground beam of the permanent supporting structure is square with a width of 0.8m~1.0m; the width of the permanent facing wall is 0.8~1.0m, and the wall height is the distance from the bottom of the pit to the top of the pit; the thickness of the permanent cover plate h15 is 0.8m~1.0m.

[0033] Another object of the present invention is to provide a support method combining temporary foundation pit support and permanent slope support for implementing the support system combining temporary foundation pit support and permanent slope support, the support method combining temporary foundation pit support and permanent slope support comprising: (1) constructing temporary support piles before foundation pit excavation; then supporting first and then excavating, the temporary support forms include internal support or anchor cables, etc., and excavating in layers until the bottom of the foundation pit is excavated; (2) after excavating to the bottom of the pit, permanent support structure piles are arranged along the inner side of the foundation pit, the piles are connected by permanent support crown beams, and the permanent support structure piles are connected by permanent support crown beams. A permanent support structure base plate is constructed between the permanent crown beam and the temporary support piles. On the base plate, permanent support structure ground beams are arranged at preset intervals along the foundation pit edge. After the basement basement is constructed, a concrete slab is set to connect the basement basement and the permanent crown beam. (3) While constructing the basement side walls and basement top plate upwards, the permanent face walls and permanent rib walls are constructed upwards. When an internal support temporary support is set in the foundation pit, it is necessary to remove the internal support while constructing upwards. The permanent face walls and permanent rib walls are cast together, and the permanent rib walls are connected to the temporary support piles by planting reinforcement bars. When the construction reaches the structural slab elevation of each basement floor, backfill the soil between the basement side wall and the permanent surface wall, and between the permanent surface wall and the temporary support piles and compact it to a certain degree. Concrete slabs and permanent middle slabs are constructed above the backfill soil and at the basement structural slab elevation to simply and effectively transfer the foundation pit soil pressure to the basement floor slab. (4) After the basement structure construction is completed, the permanent surface wall and permanent rib wall are constructed to the pit top elevation. At the same time, reserved connectors in the form of steel nails or short steel bars are installed at certain intervals on the permanent surface wall above the basement. One end of the connector The connecting piece is inserted into the permanent surface wall for no less than 40d, where d is the diameter of the connecting piece, and one end extends out of the permanent surface wall 14 by 10 to 30cm; (5) A permanent cover plate is set at the top elevation of the pit to connect the permanent surface wall, permanent rib wall, and temporary support pile crown beam together; (6) After the strength of the supporting structure reaches the designed value, the vegetation hanging net is fixed to the permanent surface wall through the reserved connecting piece, and a concrete sprayer is used to spray the designed thickness of the spraying material onto the permanent surface wall fixed with the vegetation hanging net. The spraying material is a mixture of evenly mixed grass seeds, planting soil, cement and other base materials.

[0034] Another object of the present invention is to provide a combined slope excavation support method, which uses a support system that combines the temporary foundation pit support and the permanent slope support.

[0035] In combination with all the above-mentioned technical solutions, the advantages and positive effects of the present invention are as follows: the present invention combines permanent facing walls, permanent rib walls and existing temporary support piles, and is equipped with permanent support structure piles, backfill soil, permanent middle plates, permanent cover plates, reserved connectors and vegetation hanging nets to form a combined structure with a fixed end below the basement top plate elevation and a cantilever section above the basement top plate elevation. This structure is suitable for situations where temporary foundation pit support is required to ensure smooth excavation of the foundation pit, and permanent slope support is required for the high slope above the basement that appears during the foundation pit excavation. On the one hand, the bending resistance of temporary support piles can be fully utilized, and the discrete temporary support piles can be connected with permanent rib walls and permanent face walls to form a combined structural retaining wall with an I-shaped cross-section, which has a maximum bending section modulus, meets the unity of temporary foundation pit support and permanent slope support, is safe and reliable, and does not need to set anchor rods for permanent slopes in the later stage, shortening the construction period. At the same time, it can avoid the shortcomings of poor durability of permanent anchor cables, inability to construct anchor cables when environmental requirements are high, and large deformation of rough stone concrete retaining walls and gravity retaining walls in high slopes. On the other hand, the vegetation hanging net is fixed to the permanent face wall through the reserved connectors in the permanent face wall above the basement, and then the evenly mixed spraying material is sprayed onto the permanent face wall with the vegetation hanging net using a concrete sprayer, so as to achieve the purpose of greening the environment and improving the ecological environment.

[0036] Comparison between the technology of the present invention and the prior art:

[0037]

[0038] BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 It is a structural schematic diagram of a support system combining temporary foundation pit support and permanent slope support provided by an embodiment of the present invention;

[0041] Figure 2 It is a structural schematic diagram of a support system combining temporary foundation pit support and permanent slope support provided by an embodiment of the present invention;

[0042] Figure 3 is a schematic structural diagram of a permanent support structure pile provided by an embodiment of the present invention;

[0043] In the figure: 1. Temporary supporting piles; 2. Top crown beam of temporary supporting piles; 3. Pit bottom; 4. Permanent supporting structure piles; 5. Basement floor; 6. Basement side walls; 7. Concrete slab; 8. Top crown beam of permanent supporting structure piles; 9. Permanent supporting structure floor; 10. Permanent supporting structure ground beam; 11. Backfill soil; 12. Permanent rib wall; 13. Permanent middle plate; 14. Permanent facing wall; 15. Permanent cover plate; 16. Basement roof; 17. Reserved connectors; 18. Vegetation hanging net. DETAILED DESCRIPTION

[0044] 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 embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] In view of the problems existing in the prior art, the present invention provides a support system and method combining temporary foundation pit support and permanent slope support. The present invention is described in detail below in conjunction with the accompanying drawings.

[0046] like Figures 1 to 3 As shown, the green support structure combining temporary foundation pit support and permanent slope support provided by the present invention includes: temporary support piles 1, temporary support pile top beams 2, pit bottom 3, permanent support structure piles 4, basement floor 5, basement side walls 6, concrete slabs 7, permanent support structure pile top beams 8, permanent support structure floor 9, permanent support structure ground beams 10, backfill soil layer 11, permanent rib wall 12, permanent middle plate 13, permanent surface wall 14, permanent cover plate 15, basement roof 16, reserved connectors 17, and vegetation hanging nets 18.

[0047] The cross section of temporary support pile 1 is circular, and the pile diameter is determined according to the specific situation, generally 0.6 to 1.2 m, which can directly resist the soil pressure and ensure the smooth excavation of the foundation pit;

[0048] A temporary support pile cap beam 2 is arranged on the top of the temporary support pile 1, and a permanent support structure pile 4 is arranged on one side of the temporary support pile 1. The cross section of the permanent support structure pile 4 is circular, the pile diameter is generally 0.6-1.2m, the pile length is 10-15m into the clay layer 3 of the pit bottom or 5-10m into the rock layer, and the pile spacing is the spacing between the permanent rib walls 12. The permanent support structure pile 4, as a load-bearing component, bears the deadweight of the permanent face wall 14. On the other hand, by entering the clay layer 10-15m or the rock layer 5-10m into the pit bottom 3, it plays the role of a fixed end to ensure the anti-lateral displacement capability of the permanent face wall 14.

[0049] A permanent support structure pile top cap beam 8 is arranged at the upper end of the permanent support structure pile 4. The cross section of the permanent support structure pile top cap beam 8 is square, the width b8=d4+0.2m, d4 is the pile diameter of the permanent support structure pile 4, and the height h8 is 0.8-1.0m (b is the width symbol, h is the height symbol). As a force transmission layer, the permanent support structure pile top cap beam 8 transmits the deadweight of the permanent face wall 14 to the permanent support structure pile 4, and at the same time, the permanent face wall 14, the cap beam and the permanent support structure pile 4 are tightly connected together through the steel bar anchoring effect.

[0050] A permanent face wall 14 is arranged at the upper end of the crown beam 8 of the pile top of the permanent support structure, which plays the role of a flange in the combined retaining member with an approximately I-shaped cross-section of the permanent face wall 14-permanent rib wall 12-temporary support pile 1, thereby improving the bending stiffness of the cross-section and meeting the requirements of permanent support of the slope; the permanent cover plate 15 is arranged at the upper end of the permanent face wall 14 and the upper end of the permanent rib wall 12, connecting the top of the permanent face wall 14, the top of the permanent rib wall 12 and the crown beam 2 of the temporary support pile top, and connecting the top of the permanent face wall 14, the top of the permanent rib wall 12 and the crown beam 2 of the temporary support pile top, thereby enhancing the integrity of the combined support structure.

[0051] The left sides of the permanent facing wall 14 and the permanent supporting structure pile top crown beam 8 are connected to the basement side wall 6 through a concrete slab 7. The lower left end of the basement side wall 6 is the basement bottom slab 5, and the upper left end of the basement side wall 6 is the basement top slab 16. Permanent supporting rib walls are arranged at certain intervals along the edge of the foundation pit between the temporary supporting piles and the permanent supporting facing wall.

[0052] Preferably, a permanent support structure bottom plate 9 is provided at the bottom between the permanent support structure pile top crown beam 8 and the temporary support pile 1, which can bear the weight from the permanent rib wall 12 and the permanent support structure ground beam 10 and evenly transfer it to the foundation.

[0053] A permanent support structure ground beam 10 is arranged on the upper side of the permanent support structure bottom plate 9, which transfers the weight of the upper permanent rib wall 12 to the structure bottom plate; a permanent middle plate 13 is arranged on the upper side of the permanent support structure ground beam 10, and the permanent rib wall 12 is arranged on the permanent support ground beam 10. The permanent rib wall 12 is a vertical component arranged at a certain distance along the pit edge. The permanent middle plate 13 is a horizontal component arranged at the same elevation as the concrete slab 7, between the permanent face wall and the temporary support piles.

[0054] The permanent rib wall 12, the permanent face wall 14 and the temporary support pile 1 are connected horizontally to enhance the integrity of the combined support structure. Moreover, the permanent middle plate 13 has the same elevation as the concrete plate 7 and the basement floor, which can well transmit the slope soil pressure to the basement floor, forming a close connection between the basement structure and the combined support structure. The part of the combined support structure within the basement height range can be considered as the fixed end, and the part above the basement top plate 16 elevation is the cantilever section, which can give full play to the role of the basement, reduce the length of the cantilever section, and be safe and reliable.

[0055] Preferably, a permanent rib wall 12 is provided between the temporary support pile 1 and the permanent surface wall 14, and is connected to the existing temporary support pile 1 by embedded reinforcement to form a combined retaining member with an approximately I-shaped cross-section of permanent surface wall 14-permanent rib wall 12-temporary support pile 1, wherein the permanent rib wall 12 plays the role of a web to improve the bending stiffness of the cross-section.

[0056] Preferably, the temporary supporting pile top crown beam 2 is connected to the upper end of the permanent cover plate 15 .

[0057] Preferably, a backfill soil layer is provided between the permanent support structure bottom plate 9 and the permanent middle plate 13 and between the permanent middle plates to evenly transfer the slope soil pressure to the basement floor.

[0058] Preferably, a reserved connector 17 is provided on the left side of the permanent surface wall 14. When constructing the permanent surface wall 14 above the basement, steel nails or short steel bar connectors are reserved at certain intervals. One end of the connector penetrates into the permanent surface wall 14, and the other end extends out of the surface wall by 10 to 30 cm. It is used to fix the vegetation hanging net 18, which is stretched and spread on the permanent surface wall 14 and fixed by the reserved connector 17 to serve as the growth basis of green plants and protect the stability of their root system.

[0059] Preferably, the thickness of the concrete slab 7 is 0.7m; the thickness of the permanent support structure bottom plate 9 and the permanent middle plate 13 are both 0.5m; the wall width of the permanent rib wall 12 is 0.6-0.8m, and the wall height is the distance from the pit bottom 3 to the pit top; the cross-section of the permanent support structure ground beam 10 is square with a width of 0.8m-1.0m; the wall width of the permanent face wall 14 is 0.8-1.0m, and the wall height is the distance from the pit bottom 3 to the pit top; the thickness h15 of the permanent cover plate 15 is 0.8m-1.0m.

[0060] Preferably, the thickness of the concrete slab 7 is 0.7m; the thickness of the permanent support structure bottom plate 9 and the permanent middle plate 13 are both 0.5m; the wall width of the permanent rib wall 12 is 0.6-0.8m, and the wall height is the distance from the pit bottom 3 to the pit top; the cross-section of the permanent support structure ground beam 10 is square with a width of 0.8m-1.0m; the wall width of the permanent face wall 14 is 0.8-1.0m, and the wall height is the distance from the pit bottom 3 to the pit top; the thickness h15 of the permanent cover plate 15 is 0.8m-1.0m.

[0061] The working principle of the present invention is: before excavating the foundation pit, temporary support piles 1 are constructed; then support is provided before excavation, and the temporary support is provided in the form of internal support or anchor cables, etc., and excavation is carried out in layers until the foundation pit bottom 3 is excavated.

[0062] After excavation to the pit bottom 3, the permanent support structure piles 4 are set along the inner side of the foundation pit. The piles are connected by permanent support crown beams. A permanent support structure bottom plate 9 is constructed between the permanent crown beam and the temporary support piles 1. Permanent support structure ground beams 10 are arranged on the bottom plate at preset intervals along the edge of the foundation pit. After the construction of the basement floor 5 is completed, a concrete slab 7 is set to connect the basement floor 5 and the permanent crown beam.

[0063] While constructing the basement side walls 6 and the basement top slab 16 upward, the permanent face walls 14 and permanent rib walls 12 are constructed upward. When temporary internal supports are set up in the foundation pit, it is necessary to remove the internal supports while constructing upward. The permanent face walls 14 and permanent rib walls 12 are cast together, and the permanent rib walls 12 are connected to the temporary support piles 1 through embedded reinforcement. When constructing upward to the structural layer elevation of each basement, backfill soil between the basement side walls 6 and the permanent face walls 14, and between the permanent face walls 14 and the temporary support piles 1 and compact it to a certain degree, and construct concrete slabs 7 and permanent middle plates 13 above the backfill soil and at the basement structural layer elevation, so as to simply and effectively transfer the foundation pit soil pressure to the basement floor.

[0064] After the basement structure construction is completed, continue to construct the permanent surface wall 14 and the permanent rib wall 12 to the pit top elevation. At the same time, reserved connectors 17 in the form of steel nails or short steel bars must be set at certain intervals on the permanent surface wall 14 above the basement. One end of the connector penetrates into the permanent surface wall 14 by no less than 40d (d is the diameter of the connector), and the other end extends out of the permanent surface wall 14 by 10 to 30cm.

[0065] A permanent cover plate 15 is arranged at the pit top elevation to connect the permanent face wall 14, the permanent rib wall 12 and the crown beam of the temporary support pile 1 together.

[0066] After the strength of the supporting structure reaches the designed value, the vegetation net 18 is fixed to the permanent surface wall 14 through the reserved connecting parts 17, and a concrete sprayer is used to spray the designed thickness of the spraying material onto the permanent surface wall 14 fixed with the vegetation net 18. The spraying material is a mixture of evenly mixed grass seeds, planting soil, cement and other base materials.

[0067] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0068] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A support system combining temporary foundation pit support and permanent slope support, characterized in that: The support system combining temporary foundation pit support and permanent slope support is provided with: Temporary support piles; A temporary support pile top crown beam is arranged on the top of the temporary support pile, a permanent support structure pile is arranged on one side of the temporary support pile, a permanent support structure pile top crown beam is arranged on the upper end of the permanent support structure pile, and a permanent surface wall is arranged on the upper end of the permanent support structure pile top crown beam; a permanent rib wall is arranged between the temporary support pile and the permanent surface wall; a permanent cover plate is arranged at the upper end of the permanent surface wall and the upper end of the permanent rib wall; The permanent surface wall and the left side of the permanent support structure pile top crown beam are connected to the basement side wall through a concrete slab, and permanent rib walls are arranged at regular intervals along the foundation pit edge between the temporary support piles and the permanent surface wall; A permanent support structure bottom plate is arranged at the bottom between the permanent support structure pile top crown beam and the temporary support pile, a permanent support structure ground beam is arranged on the upper side of the permanent support structure bottom plate, and a permanent rib wall is arranged on the upper side of the permanent support structure ground beam; a backfill soil layer is arranged between the permanent support structure bottom plate and the permanent middle plate; The top crown beam of the temporary support pile is connected to the upper end of the permanent cover plate; A backfill soil layer is provided between the two concrete slabs; The permanent rib wall is a vertical member arranged at a certain distance along the pit edge, and the permanent middle plate is a horizontal member set at the same elevation of the concrete slab, between the permanent face wall and the temporary support piles; A reserved connector is set on the left side of the permanent surface wall. When constructing the permanent surface wall above the basement, steel nails or short steel bar connectors are reserved at a certain distance. One end of the connector goes deep into the permanent surface wall, and the other end extends 10 to 30 cm outside the surface wall. The vegetation hanging net is fixed, stretched and spread on the permanent surface wall, and fixed through the reserved connector as the basis for the growth of green plants; The temporary support pile has a circular cross section and a pile diameter of 0.6 to 1.2 m, which is determined according to the specific situation, and directly resists the soil pressure; The cross-section of the permanent support structure piles is circular, the pile diameter is 0.6-1.2m, the pile length is 10-15m into the clay layer at the bottom of the pit or 5-10m into the rock layer, and the pile spacing is the spacing between the permanent rib walls; the permanent support structure piles serve as load-bearing components to bear the deadweight of the permanent face wall, and by entering the clay layer 10-15m or 5-10m into the rock layer at the bottom of the pit, they play the role of fixed ends and ensure the lateral displacement resistance of the permanent face wall.

2. The support system combining temporary foundation pit support and permanent slope support as claimed in claim 1 is characterized in that: The cross section of the crown beam on the top of the permanent support structure pile is square, with a width of b8 = d4 + 0.2m, d4 is the pile diameter of the permanent support structure pile, and a height of h8 of 0.8-1.0m, b is the width symbol, and h is the height symbol; as a force transmission layer, the crown beam on the top of the permanent support structure pile transmits the deadweight of the permanent face wall to the permanent support structure pile, and at the same time, the permanent face wall, the crown beam and the permanent support structure pile are tightly connected together through the steel bar anchoring action; A permanent face wall is arranged at the upper end of the crown beam of the pile top of the permanent support structure, which plays the role of a flange in the combined retaining member of the permanent face wall, permanent rib wall and temporary support pile with an approximate I-shaped cross section; the permanent cover plate is arranged at the upper end of the permanent face wall and the upper end of the permanent rib wall, connecting the top of the permanent face wall, the top of the permanent rib wall and the crown beam of the temporary support pile top, connecting the top of the permanent face wall, the top of the permanent rib wall and the crown beam of the temporary support pile top together, thereby enhancing the integrity of the combined support structure; The left side of the permanent facing wall and the permanent supporting structure pile top crown beam are connected to the basement side wall through a concrete slab. The lower left end of the basement side wall is the basement bottom slab, and the upper left end of the basement side wall is the basement top slab.

3. The support system combining temporary foundation pit support and permanent slope support as claimed in claim 1 is characterized in that: The permanent rib wall, permanent face wall and temporary support piles are connected horizontally to enhance the integrity of the composite support structure. The permanent middle plate has the same elevation as the concrete plate and basement floor, and the slope soil pressure is transmitted to the basement floor, forming a close connection between the basement structure and the composite support structure. The part of the composite support structure within the basement height range is the fixed end, and the part above the basement top plate elevation is the cantilever section.

4. The support system combining temporary foundation pit support and permanent slope support as claimed in claim 1 is characterized in that: A permanent rib wall is set between the temporary support piles and the permanent face wall, and is connected with the existing temporary support piles by planting reinforcement to form a combined retaining member with an approximate I-shaped cross-section of the permanent face wall, permanent rib wall, and temporary support piles. The permanent rib wall plays the role of a web. A backfill soil layer is set between the permanent support structure bottom plate and the permanent middle plate, and between the two concrete plates, to evenly transfer the slope soil pressure to the basement floor; The thickness of the concrete slab is 0.7m; the thickness of the bottom plate and the permanent middle plate of the permanent supporting structure are both 0.5m; the width of the permanent rib wall is 0.6~0.8m, and the wall height is the distance from the bottom of the pit to the top of the pit; the cross-section of the ground beam of the permanent supporting structure is square with a width of 0.8m~1.0m; the width of the permanent facing wall is 0.8~1.0m, and the wall height is the distance from the bottom of the pit to the top of the pit; the thickness of the permanent cover plate h15 is 0.8m~1.0m.

5. A method for combining temporary foundation pit support and permanent slope support in implementing the support system combining temporary foundation pit support and permanent slope support as described in any one of claims 1 to 4, characterized in that: The support method combining temporary foundation pit support and permanent slope support includes: (1) constructing temporary support piles before foundation pit excavation; then support first and then excavate, the temporary support form includes internal support, and excavation is carried out in layers until the bottom of the foundation pit is excavated; (2) permanent support structure piles are set along the inner side of the foundation pit after excavation to the bottom of the pit, and the piles are connected by permanent support crown beams. A permanent support structure bottom plate is constructed between the permanent support crown beam and the temporary support piles, and permanent support structure ground beams are arranged on the bottom plate at preset intervals along the edge of the foundation pit. After the basement floor is constructed, a concrete slab is set to connect the basement floor and the permanent support crown beam; (3) while constructing the basement side walls and the basement top plate upwards, permanent face walls and permanent rib walls are constructed upwards. When internal support temporary support is set in the foundation pit, it is necessary to remove the internal support while constructing upwards; the permanent face wall and the permanent rib wall are cast in place together, and the permanent rib wall and the temporary support piles are connected together by embedded reinforcement. When the construction reaches the structural layer plate elevation of each basement floor, the permanent face wall and the permanent rib wall are cast in place together. The ... , backfill soil between the side wall and the permanent surface wall of the basement and between the permanent surface wall and the temporary support piles and compact it to a certain degree, and construct concrete slabs and permanent middle slabs above the backfill soil and at the elevation of the basement structure layer, so as to simply and effectively transfer the soil pressure of the foundation pit to the basement floor slab; (4) After the construction of the basement structure is completed, continue to construct the permanent surface wall and permanent rib wall to the pit top elevation. At the same time, it is necessary to set reserved connectors in the form of steel nails or short steel bars at a certain interval on the permanent surface wall above the basement. One end of the connector penetrates into the permanent surface wall by no less than 40d, d is the diameter of the connector, and the other end protrudes 10 to 30cm outside the permanent surface wall; (5) A permanent cover plate is set at the pit top elevation to connect the permanent surface wall, permanent rib wall, and temporary support pile crown beam together; (6) After the strength of the support structure reaches the design value, the vegetation hanging net is fixed to the permanent surface wall through the reserved connector, and a concrete sprayer is used to spray the designed thickness of spray material on the permanent surface wall fixed with the vegetation hanging net.

6. A slope excavation combined support method, characterized in that: The combined slope excavation support method uses a support system combining the temporary foundation pit support and the permanent slope support as described in any one of claims 1 to 4.

Images