Foundation pit support post-dismantling inner support reserved structure
By pre-embedded steel bars and sleeves in the support beams at the overlapping part of the inner support beam and the basement exterior wall, and combined with the design of water-stop steel plates, the problems of insufficient strength of steel bar connections and waterproofing and seepage prevention in deep foundation pit support are solved, thereby improving construction safety and reducing costs.
Patent Information
- Application Number
- CN202423062466.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2034-12-11
AI Technical Summary
In existing technologies, the reinforced concrete internal bracing for deep foundation pit support suffers from insufficient horizontal reinforcement connection strength, poor construction safety, and waterproofing and seepage prevention issues during dismantling. Furthermore, the cost of threaded split sleeves is high.
At the point where the internal support beam overlaps with the basement exterior wall, pre-embedded horizontal and vertical reinforcing bars and sleeves are installed in the pre-reserved support beam. Combined with the design of the water-stop steel plate, the gaps are sealed by welding to achieve effective connection of the reinforcing bars and waterproofing.
It effectively solved the problem of stress connection between horizontal and vertical steel bars in the basement exterior wall, improved construction safety and waterproofing performance, and reduced construction costs.
Smart Images
Figure CN223593376U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the field of building construction technology, especially relates to a foundation pit support post-dismounting inner support reserved structure. BACKGROUND
[0002] With the development of city construction and underground space, deep foundation pit basement has been applied more and more, and deep foundation pit support reinforced concrete inner support needs to be replaced layer by layer and then removed along with the construction of the basement, in order to avoid the influence of the replacement and removal process on the construction of the upper structure, the post-dismounting inner support construction method is adopted.
[0003] CN220225942U discloses a vertical steel bar reserved structure for the conflict position between a foundation pit inner support and a main body structure, which realizes the setting of vertical reserved steel bars through the mechanical connection form of a steel bar connector and a screw sleeve type split sleeve, the steel bar connector at the bottom end of the vertical reserved steel bars is inserted into the foam board at the bottom of the inner support beam to realize pre-burying, which is convenient to install and does not need excessive excavation, and it is convenient to find the steel bar joint in the later stage, meanwhile, the top of the vertical reserved steel bars extends out of the inner support beam, which facilitates the installation of the positioning steel bars, can improve the burying precision of the vertical reserved steel bars, and the vertical reserved steel bars on the two support beams are connected into one through the connecting steel bars and the screw sleeve type split sleeve, which solves the problems that the upper and lower joints cannot be twisted and the connecting steel bars are difficult to install. The deficiency is that: no horizontal reserved steel bar structure is arranged, because the basement outer wall needs to bear a large horizontal load in addition to the vertical load after the earth backfilling, therefore, the connection of the horizontal steel bars is also the key of the structure; in addition, because of the foundation pit excavation and the basement structure construction stage, the exposed steel bars are easy to scratch the hoisted objects, which has a great influence on the construction safety and the protection of the exposed steel bars, and the screw sleeve type split sleeve has a high cost, which increases the construction cost. UTILITY MODEL CONTENTS
[0004] The utility model aims at providing a foundation pit support post-dismounting inner support reserved structure, so as to solve the connection stress of the horizontal steel bars and the vertical steel bars of the basement outer wall, facilitate the construction, and effectively solve the waterproof and anti-leakage problems of the post-dismounting inner support.
[0005] The technical scheme of the utility model discloses a kind of foundation pit support rear dismantling inner support reserved structure, including the reserved support beam in the coincident part of inner support beam and basement outer wall, reserved support beam is equipped with embedded basement outer wall horizontal reinforcement, embedded basement outer wall vertical reinforcement and reserved support beam main reinforcement, the opposite end of the embedded basement outer wall horizontal reinforcement is connected with the horizontal reinforcement sleeve for connecting basement outer wall horizontal reinforcement, the opposite end of the embedded basement outer wall vertical reinforcement is connected with the vertical reinforcement sleeve for connecting basement outer wall vertical reinforcement, the opposite end of the reserved support beam main reinforcement is connected with the main reinforcement sleeve for connecting inner support beam main reinforcement, and the main reinforcement sleeve is located at basement outer wall boundary line;Reserved support beam is equipped with water stop steel plate in vertical direction, a plurality of through holes for the reserved support beam main reinforcement to pass through are formed on the water stop steel plate, the reserved support beam main reinforcement is welded with the water stop steel plate after passing through the through hole, and at least part of the water stop steel plate extends out of the reserved support beam and surrounds the outside of the reserved support beam.
[0006] As preferred, the water stop steel plate is a rectangular water stop ring with an opening in the middle, which includes a first part embedded in the reserved support beam and a second part surrounding the outside of the reserved support beam, and the width of the four edges of the first part is 100-150mm, and the width of the four edges of the second part is 100-150mm.
[0007] As preferred, a plurality of through holes are arranged on the first part, and the number and position of the through holes correspond to the number and position of the reserved support beam main reinforcement, and the aperture of the through hole is 4-5mm larger than the diameter of the reserved support beam main reinforcement.
[0008] As preferred, in the case of diagonal intersection of inner support beam and crown beam, the second part is bent along the boundary line of the reserved support beam to be perpendicular to the construction joint at the opposite ends of the two sides of the reserved support beam.
[0009] As preferred, the water stop steel plate is a galvanized steel plate, and the thickness of the water stop steel plate is 3-5mm.
[0010] As preferred, the total length of the embedded basement outer wall horizontal reinforcement and the horizontal reinforcement sleeve is equal to the horizontal length of the cross section of the reserved support beam, and the total length of the embedded basement outer wall vertical reinforcement and the vertical reinforcement sleeve is equal to the vertical length of the cross section of the reserved support beam.
[0011] As preferred, the horizontal reinforcement sleeve and the vertical reinforcement sleeve are both ordinary first-level sleeves, and the horizontal reinforcement sleeve and the vertical reinforcement sleeve are both filled with foaming agent, which is removed after the concrete pouring of the inner support beam is completed.
[0012] Preferably, the reserved support beam main reinforcement is 10mm shorter than the thickness of the basement outer wall, and the two ends of the reserved support beam main reinforcement are straight threads and are galvanized.
[0013] Preferably, the reserved support beam is provided with a basement outer wall concrete pouring section on both sides, a steel mesh for separating common concrete and anti-permeable concrete is arranged between the basement outer wall concrete pouring section and the inner support beam, and the basement outer wall concrete pouring section is poured with anti-permeable concrete.
[0014] Preferably, a cushion layer is arranged below the inner support beam, the cushion layer below the reserved support beam is thickened, the thickness of the cushion layer is greater than or equal to the width of the water stop steel plate surrounding the outside of the reserved support beam, and a mounting gap for inserting the water stop steel plate is arranged on the cushion layer.
[0015] Compared with the prior art, the utility model has the beneficial effects:
[0016] (1) The basement outer wall horizontal reinforcement and horizontal reinforcement sleeve, the basement outer wall vertical reinforcement and vertical reinforcement sleeve are embedded in the reserved support beam, which facilitates construction and effectively solves the connection stress problem of the horizontal reinforcement and the vertical reinforcement of the basement outer wall.
[0017] (2) The opposite ends of the reserved support beam main reinforcement are threadedly connected with the main reinforcement sleeve for connecting the inner support beam main reinforcement, the main reinforcement sleeve is convenient to remove, the main reinforcement sleeve is located at the basement outer wall boundary line, which is beneficial to the later removal and outer wall surface repair and waterproof construction, the embedded basement horizontal reinforcement and the embedded basement vertical reinforcement are completely embedded in the reserved support beam, which can avoid scratching the hoisted object and improve construction safety and finished product protection.
[0018] (3) The water stop steel plate is embedded in the reserved support beam, at least part of the water stop steel plate extends out of the reserved support beam and surrounds the outside of the reserved support beam, and the gap between the reserved support beam main reinforcement and the water stop steel plate is welded and sealed after the reserved support beam main reinforcement is perforated, which effectively solves the waterproof and anti-leakage problem of the later removed inner support.
[0019] (4) The water stop steel plate adopts a rectangular water stop ring with a middle opening, the water stop ring can ensure the integrity and continuity of the inner support beam structure after the middle opening, so that the inner support beam concrete structure is not isolated or cut off by the water stop steel plate; the water stop steel plate can ensure the continuity of the inner support beam main reinforcement after the hole is opened, so that the inner support beam main reinforcement is not cut off by the water stop steel plate. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 is a foundation pit support section view schematic diagram of the utility model;
[0021] Figure 2 is an inner support beam local plane schematic diagram of the crown beam and the inner support orthogonal working condition;
[0022] Figure 3 is Figure 2 a partial cross-sectional view of the basement outer wall in the basement outer wall;
[0023] Figure 4 is Figure 2 a schematic diagram of the embedded shear wall horizontal steel bar and vertical steel bar in the basement outer wall;
[0024] Figure 5 is Figure 4 a schematic diagram of the horizontal steel bar and vertical steel bar in the basement outer wall;
[0025] Figure 6 is Figure 2 a schematic diagram of the reserved support beam in the basement outer wall;
[0026] Figure 7 is Figure 6 a schematic diagram of the support beam main steel bar in the reserved support beam in the basement outer wall;
[0027] Figure 8 is Figure 6 a schematic diagram of the water stop steel plate in the basement outer wall;
[0028] Figure 9 is Figure 6 a schematic diagram of the water stop steel plate in the basement outer wall;
[0029] Figure 10 is a schematic diagram of the reserved support beam in the basement outer wall;
[0030] Figure 11 is Figure 10 a schematic diagram of the water stop steel plate in the basement outer wall;
[0031] Figure 12 is Figure 10 a schematic diagram of the water stop steel plate in the basement outer wall.
[0032] Main component symbol explanation:
[0033] Reserved support beam 1, embedded basement outer wall horizontal steel bar 11, horizontal steel bar sleeve 111, embedded basement outer wall vertical steel bar 12, vertical steel bar sleeve 121, reserved support beam main steel bar 13, main steel bar sleeve 131, water stop steel plate 14, through hole 141, first part 142, second part 143, reserved support beam edge line 15, construction joint joint 16, inner support beam 2, inner support beam main steel bar 21, inner support beam stirrup 22, basement outer wall 3, basement outer wall horizontal steel bar 31, basement outer wall vertical steel bar 32, basement outer wall edge line 33, basement outer wall concrete pouring section 34, corbel 4, steel mesh 5, cushion 6, installation joint 61. DETAILED DESCRIPTION
[0034] The utility model will be further described in combination with the drawings below:
[0035] Referring to Figures 1 to 3 As shown in the figure, the utility model provides a kind of foundation pit support rear dismantling inner support reserved structure, including the reserved support beam 1 in the coincident part of inner support beam 2 and basement outer wall 3, reserved support beam 1 is equipped with embedded basement outer wall horizontal reinforcement 11, embedded basement outer wall vertical reinforcement 12 and reserved support beam main reinforcement 13, and the opposite ends of embedded basement outer wall horizontal reinforcement 11 are connected with the horizontal reinforcement sleeve 111 for connecting basement outer wall horizontal reinforcement 31, the opposite ends of embedded basement outer wall vertical reinforcement 12 are connected with the vertical reinforcement sleeve 121 for connecting basement outer wall vertical reinforcement 32, and the opposite ends of reserved support beam main reinforcement 13 are connected with the main reinforcement sleeve 131 for connecting inner support beam main reinforcement 21, as Figure 7 As shown in the figure, main reinforcement sleeve 131 is located at basement outer wall boundary line 33, to facilitate later removal and wall repair;Reserved support beam 1 is provided with water stop steel plate 14 in vertical direction, as Figure 9 As shown in the figure, a plurality of through holes 141 are formed in water stop steel plate 14 for reserved support beam main reinforcement 13 to pass through, and reserved support beam main reinforcement 13 is welded with water stop steel plate 14 after passing through through hole 141, at least part of water stop steel plate 14 extends out of reserved support beam 1 and surrounds the outside of reserved support beam 1, further ensuring the waterproof and anti-seepage performance of basement outer wall 3.
[0036] The utility model provides a kind of foundation pit support rear dismantling inner support reserved structure, by embedding basement outer wall horizontal reinforcement and horizontal reinforcement sleeve, basement outer wall vertical reinforcement and vertical reinforcement sleeve in reserved support beam, it is convenient for construction, and can effectively solve the connection stress problem of horizontal reinforcement and vertical reinforcement of basement outer wall;By embedding water stop steel plate in reserved support beam, at least part of water stop steel plate extends out of reserved support beam and surrounds the outside of reserved support beam, and the gap between reserved support beam main reinforcement and water stop steel plate is welded and sealed water stop after reserved support beam main reinforcement is perforated, can effectively solve the waterproof and anti-seepage problem of rear dismantling inner support.
[0037] Referring to Figure 9As shown, the water stop steel plate 14 is a rectangular water stop ring with a middle opening, and the water stop steel plate 14 is made of a 3-5mm thick steel plate. The water stop steel plate 14 is cut and drilled according to the cross section of the reserved support beam 1 and the arrangement of the reserved support beam main reinforcement 13, and needs to be galvanized in advance. The rectangular water stop ring is embedded during the construction of the inner support beam 2, and is installed together with the reserved support beam main reinforcement 13. After the reserved support beam main reinforcement 13 passes through the through hole, the gap between the rectangular water stop ring and the reserved support beam main reinforcement 13 is ring welded and sealed. After welding is completed, the inner support beam main reinforcement 21 is extended through the reserved support beam main reinforcement 13 and the main reinforcement sleeve 131, and the inner support beam stirrup 22 is installed. By making the water stop steel plate 14 into a rectangular water stop ring with a middle opening, the integrity and continuity of the inner support beam structure can be ensured after the middle opening of the water stop ring, so that the inner support beam concrete structure will not be isolated or cut off by the water stop steel plate. After the hole is opened on the water stop steel plate 14, the continuity of the inner support beam main reinforcement 21 can be ensured, so that the inner support beam main reinforcement 21 will not be cut off by the water stop steel plate 14.
[0038] As shown in Figure 6 , Figure 9 As shown, the rectangular water stop ring includes a first part 142 embedded in the reserved support beam 1 and a second part 143 surrounding the outside of the reserved support beam 1. The width d1 of the four edges of the first part 142 is 100-150mm, that is, the width d1 of the four edges of the rectangular water stop ring embedded in the reserved support beam 1 is 100-150mm. The width d2 of the four edges of the second part 143 is 100-150mm, that is, the width d2 of the four edges of the rectangular water stop ring exposed outside the reserved support beam 1 is 100-150mm. A plurality of through holes 141 are arranged on the first part 142, and the number and position of the through holes 141 correspond to the number and position of the reserved support beam main reinforcement 13. The diameter of the through hole 141 is 4-5mm larger than the diameter of the reserved support beam main reinforcement 13, so that the reserved support beam main reinforcement can pass through the through hole smoothly.
[0039] It is worth noting that in the case of the inner support beam 2 being orthogonal to the crown beam 4, as shown in Figure 2 , Figure 8 The rectangular water stop ring is located in the middle of the thickness direction of the basement outer wall 3, and the rectangular water stop ring and the basement outer wall 3 are located in the same vertical plane. In the case of the inner support beam 2 being diagonal to the crown beam 4, as shown in Figures 10 to 12 The rectangular water stop ring is located in the middle of the thickness direction of the basement outer wall 3, and the second part of the rectangular water stop ring is located at the opposite ends on both sides of the reserved support beam 1, which are bent along the reserved support beam edge line 15 to be perpendicular to the construction joint 16, so as to ensure the waterproof and anti-seepage performance of the basement outer wall. In this embodiment, as shown in Figure 12 The reserved support beam edge line 15 is the folding line of the water stop steel plate 14, and the water stop steel plates on both sides of the reserved support beam are bent along the folding line to be perpendicular to the construction joint 16.
[0040] In the embodiment, the water stop steel plate is made of 3-5mm thick steel plate and is galvanized before being embedded. The cutting and hole making are made according to the section of the reserved support beam and the arrangement of the reserved support beam reinforcement. The holes are made at the positions where the reserved support beam reinforcement is located. The number and positions of the through holes correspond to the number and positions of the reserved support beam reinforcement.
[0041] As shown in Figure 4 As shown in
[0042] It should be noted that, as shown in Figure 5 The diameter of the embedded horizontal reinforcement 11 of the basement outer wall is the same as that of the horizontal reinforcement 31 of the basement outer wall, and the diameter of the embedded vertical reinforcement 12 of the basement outer wall is the same as that of the vertical reinforcement 32 of the basement outer wall. The ends of the embedded horizontal reinforcement 11 of the basement outer wall are pre-threaded and connected to the horizontal reinforcement sleeve 111. Similarly, the ends of the embedded vertical reinforcement 12 of the basement outer wall are pre-threaded and connected to the vertical reinforcement sleeve 121. After the horizontal reinforcement 31 of the basement outer wall and the vertical reinforcement 32 of the basement outer wall are connected through the embedded horizontal reinforcement sleeve 111 and the vertical reinforcement sleeve 121, the basement outer wall reinforcement and the reserved support beam reinforcement can be connected to form a complete through reinforcement.
[0043] In the embodiment, the horizontal reinforcement sleeve 111 and the vertical reinforcement sleeve 121 are both ordinary first-level sleeves, so that the strength of the sleeve is higher than that of the horizontal reinforcement of the basement outer wall and the vertical reinforcement of the basement outer wall, to ensure that the connection of the horizontal reinforcement of the basement outer wall and the vertical reinforcement of the basement outer wall in the same section meets the strength requirement. The horizontal reinforcement sleeve 111 and the vertical reinforcement sleeve 121 are both filled with foaming agent to prevent the cement slurry from flowing into the sleeve during the pouring of the inner support beam concrete. The foaming agent is removed after the pouring of the inner support beam concrete is completed. During the subsequent basement outer wall construction stage, the foaming agent is removed and the horizontal reinforcement of the basement outer wall and the vertical reinforcement of the basement outer wall are connected.
[0044] It should be noted that, as shown in Figure 7As shown, the reserved support beam main reinforcement 13 is 10mm shorter than the thickness of the basement outer wall 3, the two ends of the reserved support beam main reinforcement 13 are straight threads and are galvanized, the two ends of the reserved support beam main reinforcement 13 are threadedly connected to the main reinforcement sleeve 131, and the sleeve is convenient for disassembly; after the inner support beam 2 is cut and removed, the threadedly connected main reinforcement sleeve 131 is removed, and the position left by the main reinforcement sleeve 131 is filled with waterproof mortar protection layer, which prevents the steel from rusting from the outside to the inside, and is beneficial to the repair and waterproof construction of the outer wall.
[0045] As shown in Figure 3 As shown, the reserved support beam 1 is formed with a basement outer wall concrete pouring section 34 on both sides, a steel wire mesh 5 for separating ordinary concrete and impermeable concrete is arranged between the basement outer wall concrete pouring section 34 and the inner support beam 2, and the basement outer wall concrete pouring section 34 is poured with impermeable concrete. Because the basement outer wall concrete has impermeability requirements, the strength of the basement outer wall is generally higher than that of the inner support beam concrete. In order to meet the requirements of the basement outer wall concrete, the steel wire mesh 5 is installed on both sides of the basement outer wall boundary line 33 for isolation between the different concretes of the basement outer wall 3 and the inner support beam 2. During concrete pouring, the basement outer wall concrete pouring section 34 is first poured with the same concrete as the basement outer wall, and then the inner support beam part of the concrete pouring section 34 outside the basement outer wall concrete pouring section 34 is poured with the inner support beam concrete.
[0046] As shown in Figure 3 As shown, a cushion layer 6 is arranged below the inner support beam 2, the cushion layer below the reserved support beam 1 is thickened, the thickness is greater than or equal to the width d2 of the second part of the water stop steel plate 14 around the outside of the reserved support beam 1, and the installation slot 61 for inserting the water stop steel plate 14 is arranged on the cushion layer 6.
[0047] In the embodiment, as shown in Figure 3 As shown, the thickness of the cushion layer 6 below the reserved support beam 1 and the depth of the installation slot formed on the cushion layer are equal to the width d2 of the second part of the water stop steel plate 14, so that the exposed part of the water stop steel plate can be completely inserted into the installation slot 61 of the cushion layer, and the installation of the water stop steel plate 14 is facilitated. The cushion layer 6 pouring construction process is as follows: before pouring the cushion layer of the inner support beam, the positions of the basement outer wall 3 and the water stop steel plate 14 are positioned and laid out, the position of the cushion layer of the reserved support beam 1 is excavated and thickened, so that the thickness of the cushion layer 6 is equal to the width d2 of the second part of the water stop steel plate 14 exposed, and in the embodiment, the width d2 of the second part is 100-150mm; when the inner support beam is poured with the cushion layer, the installation slot 61 of the water stop steel plate 14 is left, so that in the subsequent installation process of the water stop steel plate 14, the water stop steel plate 14 can be inserted into the cushion layer 6; after the inner support beam is poured with the cushion layer, the basement outer wall boundary line and the water stop steel plate are accurately positioned and laid out on the cushion layer, so as to be pre-buried subsequently.
[0048] The above merely describes preferred embodiments of the present application, and any changes or modifications made within the scope of the present application should fall within the scope of the present application.
Claims
1. A reserved structure of inner support for back dismantling of a foundation pit support, characterized in that, The reserved support beam includes a reserved support beam located at the coincident position of the inner support beam and the basement outer wall, a pre-buried basement outer wall horizontal steel bar, a pre-buried basement outer wall vertical steel bar and a reserved support beam main bar are arranged in the reserved support beam, opposite ends of the pre-buried basement outer wall horizontal steel bar are connected with horizontal steel bar sleeves for connecting the basement outer wall horizontal steel bar, opposite ends of the pre-buried basement outer wall vertical steel bar are connected with vertical steel bar sleeves for connecting the basement outer wall vertical steel bar, opposite ends of the reserved support beam main bar are connected with main bar sleeves for connecting the inner support beam main bar, the main bar sleeves are located at the basement outer wall boundary line, a water stop steel plate is arranged in the reserved support beam along the vertical direction, a plurality of through holes are formed in the water stop steel plate for the reserved support beam main bar to pass through, the reserved support beam main bar is welded with the water stop steel plate after passing through the through holes, at least part of the water stop steel plate extends out of the reserved support beam and surrounds the outside of the reserved support beam.
2. The reserved structure of the inner support of the rear disassembly of the foundation pit support according to claim 1, characterized in that, The water stop steel plate is a rectangular water stop ring with an opening in the middle, the rectangular water stop ring includes a first part embedded in the reserved support beam and a second part surrounding the outside of the reserved support beam, the four edges of the first part have a width of 100-150 mm, and the four edges of the second part have a width of 100-150 mm.
3. The reserved structure of the inner support of the rear dismounting of the foundation pit support according to claim 2, characterized in that, The plurality of through holes are arranged on the first part in a spaced manner, the number and position of the through holes correspond to the number and position of the reserved support beam main bar, and the diameter of the through holes is greater than the diameter of the reserved support beam main bar by 4-5 mm.
4. The retaining and stripping structure according to claim 2, wherein, In the case that the inner support beam and the crown beam are oblique, the second part is bent along the boundary line of the reserved support beam to be perpendicular to the construction joint at opposite ends of the two sides of the reserved support beam.
5. The reserved structure of the inner support of the rear dismounting of the foundation pit support according to any one of claims 1-4, characterized in that, The water stop steel plate is a galvanized steel plate, and the thickness of the water stop steel plate is 3-5 mm.
6. The post-excavation bracing and pre-reserved structure of the foundation pit support according to claim 1, characterized in that, The total length of the pre-buried basement outer wall horizontal steel bar and the horizontal steel bar sleeve is equal to the horizontal length of the cross section of the reserved support beam, and the total length of the pre-buried basement outer wall vertical steel bar and the vertical steel bar sleeve is equal to the vertical length of the cross section of the reserved support beam.
7. The retaining and stripping structure according to claim 6, wherein, The horizontal steel bar sleeve and the vertical steel bar sleeve are both ordinary first-level sleeves, the horizontal steel bar sleeve and the vertical steel bar sleeve are both filled with foaming agent, and the foaming agent is removed after the concrete pouring of the inner support beam is completed.
8. The post-excavation bracing and pre-reserved structure of the foundation pit support according to claim 1, characterized in that, The length of the reserved support beam main bar is 10 mm shorter than the thickness of the basement outer wall, and the two ends of the reserved support beam main bar are straight threads and are galvanized.
9. The post-excavation bracing and pre-reserved structure of the foundation pit support according to claim 1, characterized in that, The two sides of the reserved support beam form a basement outer wall concrete pouring section, a steel mesh for separating ordinary concrete and impermeable concrete is arranged between the basement outer wall concrete pouring section and the inner support beam, and the basement outer wall concrete pouring section is poured with impermeable concrete.
10. The post-excavation bracing and pre-reserved structure of the foundation pit support according to claim 1, characterized in that, A cushion layer is arranged below the inner support beam, the cushion layer below the reserved support beam is thickened, the thickness of the cushion layer is greater than or equal to the width of the water stop steel plate surrounding the outside of the reserved support beam, and a mounting joint for inserting the water stop steel plate is arranged on the cushion layer.