Construction method of prefabricated assembly type foundation pit support replacing blade wall

Abstract

In order to solve the problems of low construction efficiency and poor stability of the existing support, the application provides a construction method of prefabricated assembly type foundation pit support replacement knife wall, which comprises the following steps: first step: the construction personnel first carries out relevant construction work on the structure bottom plate cushion layer arranged at the bottom layer of the foundation pit, binds the steel bars of the structure bottom plate to be constructed to finally form a steel framework, then binds a pre-buried screw rod on the steel framework according to the design drawing requirements, installs the pre-buried part, adjusts the elevation of the pre-buried part to the specified position through the nut according to the design drawing, and finally pours the structure bottom plate concrete. The construction method has reasonable overall design, simple steps and convenient operation. The prefabricated assembly type knife wall unit is used to form an overall effective force transmission, prestress can be applied to effectively control the deformation of the foundation pit, the construction efficiency of the support replacement is improved, the overall foundation pit construction speed is accelerated, the influence of the foundation pit excavation on the surrounding environment is reduced, and the purpose of safe production is achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of building construction of bracing blade wall, and particularly relates to a construction method of prefabricated assembly type bracing blade wall of foundation pit. BACKGROUND

[0002] Bracing is a commonly used technique in foundation pit engineering, which principle is to let the support pile generate partial stress due to the removal of internal support, which is transmitted to the third party with sufficient bearing capacity through the force transmission member, so as to achieve new stress balance. The bracing technique can be applied to various situations, including but not limited to the support of foundation pit, the construction of basement structure, etc. There are various methods of bracing, including inclined bracing, horizontal rigid member bracing, and using backfill or special materials, etc.

[0003] With the development of building construction technology, various large deep foundation pits are increasing, and there are construction conditions of foundation pit bracing in soft soil conditions. During the construction of underground structure, the design of foundation pit bracing directly affects the quality, safety, efficiency and cost of the project.

[0004] The existing bracing system is mainly cast-in-place reinforced concrete bracing and steel bracing. Although the cast-in-place reinforced concrete bracing has high stiffness, small deformation and safety, its main disadvantage is long construction period, difficult to remove, and materials cannot be reused. Although the steel bracing has the advantages of easy installation, convenient disassembly and recycling and reuse, the steel bracing has the disadvantage of small stiffness and easy instability, which brings great inconvenience to the construction personnel in the construction of foundation pit bracing. SUMMARY

[0005] In order to effectively improve the construction efficiency and stability of bracing, the present application provides a construction method of prefabricated assembly type bracing blade wall of foundation pit.

[0006] The technical scheme of the construction method of prefabricated assembly type bracing blade wall of foundation pit of the present application is as follows:

[0007] A construction method of prefabricated assembly type bracing blade wall of foundation pit, characterized in that the construction method comprises the following steps:

[0008] The first step: the construction personnel first carries out relevant construction work on the structure bottom plate cushion layer arranged at the bottom layer of the foundation pit, binds the steel bars of the structure bottom plate to be constructed to finally form a steel reinforcement cage, then binds a pre-buried screw rod on the steel reinforcement cage according to the design drawing requirements, installs the pre-buried part and adjusts the elevation to the specified position through the nut according to the design drawing, and finally pours the structure bottom plate concrete;

[0009] Second step: after the first step, after the structure bottom plate concrete reaches the strength requirement, the blade wall hoisting construction is carried out, and during the hoisting process, the protrusions arranged at the lower end of the blade wall are aligned with the grooves of the embedded parts one by one, the blade wall and the embedded parts are fixed through the embedded screw rods, and the perpendicularity of the blade wall is adjusted;

[0010] Third step: force transmission connection is performed between the side of the blade wall close to the ground wall and the ground wall;

[0011] Fourth step: after the installation between the blade wall and the ground wall is completed and qualified, the last support for supporting the foundation pit bottom layer is removed;

[0012] Fifth step: after the last support is removed and cleaned, the scaffolding and formwork are erected, and relevant preparation work is carried out for the pre-embedded installation of the embedded parts of the adjacent upper blade wall;

[0013] Sixth step: during the floor formwork process, the embedded part area replaces the floor formwork to install the floor bottom clamping steel plate, the embedded bolt and the embedded part are installed during the steel bar binding process, the horizontal degree of the embedded part is adjusted through the nut of the embedded bolt, and finally the floor concrete is poured;

[0014] Seventh step: after the floor concrete reaches the strength requirement, the blade wall hoisting construction is carried out, and during the hoisting process, the protrusions arranged at the lower end of the blade wall are aligned with the grooves of the embedded parts one by one, the blade wall and the embedded parts are fixed through the embedded screw rods, and the perpendicularity of the blade wall is adjusted;

[0015] Eighth step: force transmission connection is performed between the side of the blade wall close to the ground wall and the ground wall;

[0016] Ninth step: after the installation between the blade wall and the ground wall is completed and qualified, the last support for supporting the layer is removed;

[0017] Tenth step: the relevant work of the fifth step to the ninth step is repeated, and the construction is carried out to the top plate. After the underground structure construction is completed and the maintenance reaches the design strength, the blade walls of each layer are removed and recycled layer by layer, and thus the entire foundation pit support replacement construction is completed.

[0018] Further, the blade wall has two types, namely, a general prefabricated assembled blade wall and a prestressed prefabricated assembled blade wall.

[0019] Further, the ordinary prefabricated assembled blade wall adopts the grouting mode to transmit force with the ground wall, after the ordinary prefabricated assembled blade wall is hoisted, the ordinary prefabricated assembled blade wall is provided with a tetrafluoroethylene friction-reducing plate on the side close to the ground wall, the ordinary formwork is used to seal the gap between the tetrafluoroethylene friction-reducing plate and the ground wall to prevent grouting leakage, and then the gap between the tetrafluoroethylene friction-reducing plate and the ground wall is poured, and thus the construction of the structure bottom plate force transmission structure is completed.

[0020] Further, the prestressed prefabricated assembled blade wall adopts the hydraulic jack to apply prestress to transmit force with the ground wall, after the prestressed prefabricated assembled blade wall is hoisted, the foot, the hydraulic jack and the I-beam are sequentially installed between the prestressed prefabricated assembled blade wall and the ground wall, the I-beam connected with the hydraulic jack and the ground wall is ensured to be stable, the foot of the hydraulic jack and the prestressed prefabricated assembled blade wall are ensured to be in contact, and then the hydraulic jack is started to make the axial force between the ground wall and the blade wall reach the same axial force as the supporting servo jack.

[0021] Further, the embedded part of the blade wall is rigidly connected through the embedded screw rod and the bottom plate steel bar, the vertical height of the embedded part can be adjusted vertically through the embedded screw rod before pouring concrete, so that the overall levelness of the embedded part is ensured, and the blade wall is arranged on both sides of each ground wall supporting beam at a horizontal distance of 2m from the supporting beam.

[0022] Further, two screw rod lifting lugs are welded at the upper end of the blade wall, and the two screw rod lifting lugs are used as lifting points for hoisting construction.

[0023] Further, during the embedding of the embedded part, the embedded part and the bottom clamping plate are fixed on the floor through bolts, and the size of the bottom clamping plate is 4000mm in length, 540mm in width and 20mm in thickness.

[0024] The construction method of the prefabricated assembled blade wall for foundation pit support replacement is reasonable in overall design, simple in steps and convenient to operate, the prefabricated assembled blade wall unit is used to form overall effective force transmission, prestress can be applied to effectively control the deformation of the foundation pit, the construction efficiency of support replacement is improved, the overall foundation pit construction speed is improved, the influence of foundation pit excavation on the surrounding environment is reduced, the purpose of safe production is achieved, destructive demolition is not required in the later period, the damage to the bottom plate is avoided, the blade wall area is easily cleaned during rapid demolition, the construction quality of the underground structure is ensured, the reuse of the foundation pit support replacement temporary measure structure is realized, the material waste of the foundation pit temporary measure is reduced, the construction waste is reduced, and the carbon emission amount during the foundation pit construction process is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1It is the plane arrangement drawing of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0026] Figure 2 It is the elevation arrangement drawing of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0027] Figure 3 It is the structural schematic diagram of the blade wall of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0028] Figure 4 It is the left view of the blade wall of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0029] Figure 5 It is the bottom plate construction schematic diagram of the bottom layer of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0030] Figure 6 It is the hoisting construction schematic diagram of the blade wall of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0031] Figure 7 It is the pre-buried installation construction schematic diagram of the pre-buried part of the blade wall of the adjacent upper layer of the bottom layer of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0032] Figure 8 It is the hoisting construction schematic diagram of the blade wall of the adjacent upper layer of the bottom layer of embodiment 1 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0033] Figure 9 It is the plane arrangement drawing of embodiment 2 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0034] Figure 10 It is the elevation arrangement drawing of embodiment 2 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0035] Figure 11 It is the structural schematic diagram of the blade wall of embodiment 2 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0036] Figure 12 It is the left view of the blade wall of embodiment 2 of a prefabricated assembly type foundation pit support replacing blade wall construction method of the application.

[0037] Figure 13is a bottom plate construction schematic view of a foundation bottom layer of embodiment 2 of a construction method of a prefabricated assembly type foundation support replacement blade wall of the present application.

[0038] Figure 14 is a hoisting construction schematic view of a blade wall of embodiment 2 of a construction method of a prefabricated assembly type foundation support replacement blade wall of the present application.

[0039] Figure 15 is a pre-embedded installation construction schematic view of a pre-embedded part of a blade wall of an adjacent upper layer of a bottom layer of embodiment 2 of a construction method of a prefabricated assembly type foundation support replacement blade wall of the present application.

[0040] Figure 16 is a hoisting construction schematic view of a blade wall of an adjacent upper layer of a bottom layer of embodiment 2 of a construction method of a prefabricated assembly type foundation support replacement blade wall of the present application. DETAILED DESCRIPTION

[0041] The present application will be further described below in conjunction with the drawings and specific embodiments. The advantages and features of the present application will be more apparent according to the following description and claims. It should be noted that the drawings are all very simplified and use non-precise proportions, only to facilitate, clearly assist in the purpose of explaining the embodiments of the present application.

[0042] Embodiment 1

[0043] Reference Figures 1 to 8 The construction method of a prefabricated assembly type foundation support replacement blade wall of the present embodiment is characterized in that the construction method comprises the following steps:

[0044] The first step: the construction personnel first perform relevant construction work on the structural bottom plate cushion layer 104 arranged at the foundation bottom layer, bind the steel bars of the structure bottom plate 103 to be constructed to finally form a steel bar framework, then bind the pre-embedded screw rod 3 on the steel bar framework according to the design drawing requirements, install the pre-embedded part 2 and adjust the elevation thereof to the specified position through the nut according to the design drawing, and finally pour the structural bottom plate concrete.

[0045] The standard size of the pre-embedded part 2 of the common prefabricated assembly type blade wall 1 is 4000 mm in length and 540 mm in width, and 10 grooves 8 are arranged thereon, the standard size of the groove 8 is 300 mm in length, 200 mm in width, and 100 mm in depth. The pre-embedded screw rod 3 is 20 mm in diameter, and the embedded depth thereof is not less than 1 / 3 of the thickness of the structural bottom plate 103, and the pre-embedded screw rod 3 is bound and fixed with the steel bars of the structural bottom plate 103.

[0046] Second step: after the first step, the ordinary prefabricated assembled blade wall 1 is hoisted and constructed after the concrete of the structure bottom plate 103 reaches the strength requirement. During hoisting, the protrusions 9 arranged at the lower end of the ordinary prefabricated assembled blade wall 1 are aligned with the grooves 8 of the embedded parts 2 one by one, the ordinary prefabricated assembled blade wall 1 and the embedded parts 2 are fixed through the embedded screw rods 3, and the perpendicularity of the ordinary prefabricated assembled blade wall 1 is adjusted;

[0047] There are 40 groups of embedded screw rods 3 on the embedded parts 2 of the ordinary prefabricated assembled blade wall 1. The embedded parts 2 are arranged on the bottom plate reinforcement cage and connected with the bottom plate reinforcement cage plate through the embedded screw rods 3. The horizontal degree of the embedded parts 2 is adjusted through the embedded screw rods 3 and the nuts arranged at the bottom of the embedded parts 2.

[0048] The protrusions 9 of the ordinary prefabricated assembled blade wall 1 are aligned with the grooves 8 of the embedded parts 2 one by one. There are 10 protrusions 9 corresponding to the embedded parts 2 for each ordinary prefabricated assembled blade wall 1. The ground wall 101 transmits force to the structure bottom plate 103 through the engagement of the protrusions 9 of the ordinary prefabricated assembled blade wall 1 and the grooves 8 of the embedded parts 2.

[0049] The standard size of the ordinary prefabricated assembled blade wall 1 is 4000 mm in length, 300 mm in width and 2500 mm in height. The wing plates 7 and the corner codes 6 with a width of 100 mm are arranged on both sides. The ordinary prefabricated assembled blade wall 1 is matched through the protrusions 9 and the grooves 8 and is rigidly connected through the embedded screw rods 3. The horizontal stability of the ordinary prefabricated assembled blade wall 1 is ensured through the wing plates 7 and the corner codes 6 on both sides.

[0050] Third step: the ordinary prefabricated assembled blade wall 1 is connected with the ground wall 101 through force transmission on the side close to the ground wall 101. The ordinary prefabricated assembled blade wall 1 is connected with the ground wall 101 through grouting. After the hoisting of the ordinary prefabricated assembled blade wall 1 is completed, the side of the ordinary prefabricated assembled blade wall 1 close to the ground wall 101 is provided with a tetrafluoroethylene wear plate 4. The gap between the tetrafluoroethylene wear plate 4 and the ground wall 101 is sealed on both sides by using the ordinary formwork to prevent grouting leakage during grouting. Then, the gap between the tetrafluoroethylene wear plate 4 and the ground wall 101 is poured, and the construction of the force transmission structure of the structure bottom plate 103 is completed.

[0051] Fourth step: after the installation between the ordinary prefabricated assembled blade wall 1 and the ground wall 101 is completed and detected to be qualified, the last support 102 for supporting the bottom layer of the foundation pit is removed.

[0052] Fifth step: after the removal and cleaning of the last support 102 are completed, the scaffolding and formwork are erected, and the preparation work for the embedded installation of the embedded parts 2 of the ordinary prefabricated assembled blade wall 1 of the adjacent upper layer is carried out.

[0053] Sixth step: In the process of floor formwork, the embedded part area replaces the floor formwork with the floor bottom clamping steel plate for installation, the embedded screw rod 3 and the embedded part 2 are installed in the process of steel bar binding, the horizontal degree of the embedded part 2 is adjusted through the nut of the embedded screw rod 3, and finally the floor concrete is poured;

[0054] Seventh step: After the floor concrete reaches the strength requirement, the hoisting construction of the ordinary prefabricated assembled blade wall 1 is carried out, the convex teeth 9 arranged at the lower end of the ordinary prefabricated assembled blade wall 1 are aligned with the grooves 8 of the embedded part 2 one by one in the hoisting process, the ordinary prefabricated assembled blade wall 1 and the embedded part 2 are fixed through the embedded screw rod 3, and the perpendicularity of the ordinary prefabricated assembled blade wall 1 is adjusted.

[0055] Eighth step: The force transmission connection is carried out between the side of the ordinary prefabricated assembled blade wall 1 close to the ground wall 101 and the ground wall 101, after the hoisting of the ordinary prefabricated assembled blade wall 1 is completed, the tetrafluoroethylene wear-reducing plate 4 is installed on the side of the ordinary prefabricated assembled blade wall 1 close to the ground wall 101, the gap between the tetrafluoroethylene wear-reducing plate 4 and the ground wall 101 is sealed on both sides by using the ordinary formwork to prevent grouting leakage in the grouting process, and then the gap between the tetrafluoroethylene wear-reducing plate 4 and the ground wall 101 is poured, thus completing the construction of the force transmission structure of the structure bottom plate 103;

[0056] Ninth step: After the installation between the ordinary prefabricated assembled blade wall 1 and the ground wall 101 is completed and the detection is qualified, the last support 102 for supporting the layer is removed.

[0057] Tenth step: The related work of the fifth step to the ninth step is repeated, and the construction is carried out to the top plate, after the underground structure construction is completed and the maintenance reaches the design strength, the ordinary prefabricated assembled blade wall 1 of each layer is removed and recycled layer by layer, thus completing the whole support replacement construction of the foundation pit.

[0058] As a preferred embodiment, the embedded part 2 of the ordinary prefabricated assembled blade wall 1 is rigidly connected through the embedded screw rod 3 and the bottom plate steel bar, the horizontal height of the embedded part 2 can be vertically adjusted before pouring the concrete through the embedded screw rod 3, so as to ensure the overall horizontal degree of the embedded part 2, and the ordinary prefabricated assembled blade wall 1 is arranged on both sides of each ground wall support beam with a horizontal distance of 2m from the support beam.

[0059] As a preferred embodiment, two screw rod lifting lugs 15 are welded at the upper end of the ordinary prefabricated assembled blade wall 1, the two screw rod lifting lugs 15 are used as hoisting points for hoisting construction, and this structure can more conveniently hoist the blade wall to the required position.

[0060] As a preferred embodiment, during the embedding process of the embedded part 2, the embedded part 2 and the bottom clamping plate are fixed on the floor 106 through the embedded screw rod 3. The size of the bottom clamping plate is 4000 mm in length, 540 mm in width, and 20 mm in thickness.

[0061] Embodiment 2

[0062] Reference Figures 9 to 16 The embodiment provides a construction method of a prefabricated and assembled foundation pit support-changing blade wall, and the construction method comprises the following steps:

[0063] In the first step, a construction worker first performs relevant construction work on a structural floor mat layer 104 arranged at the bottom of a foundation pit, binds steel bars of a to-be-constructed structural floor 103 to finally form a steel reinforcement cage, then binds embedded screw rods 3 on the steel reinforcement cage according to a design drawing, installs embedded parts 2, and adjusts the elevations of the embedded parts 2 to specified positions through nuts according to the design drawing, and finally pours structural floor concrete.

[0064] The embedded part 2 of the prestressed prefabricated and assembled blade wall 11 has a standard size of 4000 mm in length and 540 mm in width, and 10 grooves 8 are arranged on the embedded part 2. The standard size of each groove 8 is 300 mm in length, 200 mm in width, and 100 mm in depth. The embedded screw rod 3 has a diameter of 20 mm, and the embedded depth of the embedded screw rod 3 is not less than 1 / 3 of the thickness of the structural floor 103. The embedded screw rod 3 is fixedly bound with the steel bars of the structural floor 103.

[0065] In the second step, after the first step is completed and the structural floor 103 concrete reaches the strength requirement, the hoisting construction of the prestressed prefabricated and assembled blade wall 11 is performed. During the hoisting process, the protruding teeth 9 arranged at the lower end of the prestressed prefabricated and assembled blade wall 11 are aligned with the grooves 8 of the embedded part 2 one by one, the ordinary prefabricated and assembled blade wall 1 and the embedded part 2 are fixed through the embedded screw rod 3, and the perpendicularity of the ordinary prefabricated and assembled blade wall 1 is adjusted.

[0066] There are 40 groups of embedded screw rods 3 on the embedded part 2 of the prestressed prefabricated and assembled blade wall 11. The embedded part 2 is arranged on the bottom plate steel reinforcement cage and is bound with the bottom plate steel reinforcement cage through the embedded screw rods 3. The levelness of the embedded part 2 is adjusted through the embedded screw rods 3 and the nuts arranged at the bottom of the embedded part 2.

[0067] The protruding teeth 9 of the prestressed prefabricated and assembled blade wall 11 are aligned with the grooves 8 of the embedded part 2 one by one. There are 10 protruding teeth 9 corresponding to the embedded part 2 for each fan of the prestressed prefabricated and assembled blade wall 11. The ground wall 101 transmits force to the structural floor 103 through the engagement of the protruding teeth 9 of the ordinary prefabricated and assembled blade wall 1 and the grooves 8 of the embedded part 2.

[0068] The standard size of the prestressed prefabricated assembled blade wall 11 is 4000mm in length, 300mm in width, and 2500mm in height, 100mm wing plates 7 and angle codes 6 are arranged on both sides, the prestressed prefabricated assembled blade wall 11 is matched through the protrusions 9 and the grooves 8, and is rigidly connected through the embedded screw rods 3, and the horizontal stability of the ordinary prefabricated assembled blade wall 1 is ensured through the wing plates 7 and the angle codes 6 on both sides.

[0069] The third step is to connect the force between the side of the prestressed prefabricated assembled blade wall 11 close to the ground wall 101 and the ground wall 101, and the prestressed prefabricated assembled blade wall 11 is connected to the ground wall 101 through the hydraulic jack 13 in the prestressed manner, after the prestressed prefabricated assembled blade wall 11 is hoisted, the foot 12, the hydraulic jack 13, and the I-beam 14 are sequentially installed between the prestressed prefabricated assembled blade wall 11 and the ground wall 101, the I-beam 14 connected with the ground wall 101 contacted by the hydraulic jack 13 is stably connected, the foot 12 of the hydraulic jack 13 is in contact with the prestressed prefabricated assembled blade wall 11, and then the hydraulic jack 13 is opened, so that the axial force between the ground wall 101 and the prestressed prefabricated assembled blade wall 11 reaches the same axial force as the supporting servo jack;

[0070] The fourth step is to remove the last support 102 for supporting the bottom layer of the foundation pit after the installation between the prestressed prefabricated assembled blade wall 11 and the ground wall 101 is completed and the detection is qualified.

[0071] The fifth step is to start to erect the scaffold and the formwork after the last support 102 is removed and cleaned, and to make relevant preparation work for the embedded installation of the embedded part 2 of the prestressed prefabricated assembled blade wall 11 of the adjacent upper layer.

[0072] The sixth step is that in the process of supporting the floor, the floor bottom clamping steel plate is installed instead of the floor formwork in the embedded part area, the embedded screw rod 3 and the embedded part 2 penetrating through the floor are installed in the process of reinforcing steel bar binding, the horizontal degree of the embedded part 2 is adjusted through the nut of the embedded screw rod 3, and finally the floor concrete is poured.

[0073] The seventh step is to hoist the prestressed prefabricated assembled blade wall 11 after the floor concrete reaches the strength requirement, the protrusions 9 arranged at the lower end of the prestressed prefabricated assembled blade wall 11 are aligned with the grooves 8 of the embedded part 2 one by one in the hoisting process, the prestressed prefabricated assembled blade wall 11 and the embedded part 2 are fixed through the embedded screw rod 3, and the perpendicularity of the prestressed prefabricated assembled blade wall 11 is adjusted.

[0074] The eighth step is to connect the prestressed prefabricated assembled blade wall 11 close to the side of the ground wall 101 and the ground wall 101, and after the prestressed prefabricated assembled blade wall 11 is hoisted, the foot 12, the hydraulic jack 13 and the I-beam 14 are sequentially installed between the prestressed prefabricated assembled blade wall 11 and the ground wall 101, the I-beam 14 connected with the ground wall 101 contacted by the hydraulic jack 13 is ensured to be stable, and the foot 12 of the hydraulic jack 13 is in contact with the prestressed prefabricated assembled blade wall 11, then the hydraulic jack 13 is opened, and the axial force between the ground wall 101 and the prestressed prefabricated assembled blade wall 11 reaches the same axial force as the supporting servo jack;

[0075] The ninth step is to remove the last support 102 for supporting the layer after the prestressed prefabricated assembled blade wall 11 and the ground wall 101 are installed and detected to be qualified.

[0076] The tenth step is to repeat the related work of the fifth step to the ninth step, and the construction is stopped until the top plate is reached, and after the underground structure construction is completed and the maintenance reaches the design strength, the prestressed prefabricated assembled blade wall 11 of each layer is removed and recycled layer by layer, and the whole foundation pit support replacement construction is completed.

[0077] The construction method of the prefabricated assembled foundation pit support replacement blade wall of the embodiment is reasonable in overall design, simple in steps and convenient to operate, the prestressed prefabricated assembled blade wall unit is used to form an overall effective force transmission, prestress can be applied to effectively control the deformation of the foundation pit, the support replacement construction efficiency is accelerated, the overall foundation pit construction speed is accelerated, the influence of the foundation pit excavation on the surrounding environment is reduced, the purpose of safe production is achieved, in addition, destructive demolition is not required in the later period, damage to the bottom plate is avoided, the blade wall area is easily cleaned during rapid demolition, the construction quality of the underground structure is ensured, the reuse of the foundation pit support replacement temporary measure structure is realized, the material waste of the foundation pit temporary measure and the construction waste are reduced, and the carbon emission amount during the foundation pit construction process is reduced.

[0078] The above description is only a description of the preferred embodiment of the application, and does not limit the scope of the application, and any modification and modification made by a person skilled in the art according to the above disclosure is within the protection scope of the claims.

Claims

1. A construction method of a prefabricated assembled bracing blade wall of a foundation pit, characterized in that, The construction method comprises the following steps: First step: the construction personnel first perform relevant construction work on the structure bottom plate cushion layer (104) arranged at the bottom layer of the foundation pit, bind the steel bars of the structure bottom plate (103) to be constructed to finally form a steel bar framework, then bind the embedded screw rod (3) on the steel bar framework according to the design drawing requirements, install the embedded part (2) and adjust the elevation of the embedded part (2) to the specified position through the nut according to the design drawing, and finally pour the structure bottom plate concrete; Second step: after the first step is completed, after the structure bottom plate (103) concrete reaches the strength requirement, the hoisting construction of the blade wall is performed, and during the hoisting process, the protrusions (9) arranged at the lower end of the blade wall are aligned with the grooves (8) of the embedded part (2) one by one, the blade wall and the embedded part (2) are fixed through the embedded screw rod (3), and the perpendicularity of the blade wall is adjusted; Third step: the side of the blade wall close to the ground wall (101) is connected in force with the ground wall (101); Fourth step: after the installation between the blade wall and the ground wall (101) is completed and is detected to be qualified, the last support (102) for supporting the bottom layer of the foundation pit is removed; Fifth step: after the last support is removed and cleaned, the scaffold and the formwork are erected, and relevant preparation work is performed for the pre-embedded installation of the embedded part (2) of the blade wall of the adjacent upper layer; Sixth step: during the formwork supporting process of the floor slab, the floor slab bottom clamping steel plate is installed instead of the floor slab formwork in the embedded part area, the embedded screw rod (3) and the embedded part (2) penetrating through the floor are installed during the steel bar binding process, the horizontal degree of the embedded part (2) is adjusted through the nut of the embedded screw rod (3), and finally the floor slab concrete is poured; Seventh step: after the floor slab concrete reaches the strength requirement, the hoisting construction of the blade wall is performed, and during the hoisting process, the protrusions (9) arranged at the lower end of the blade wall are aligned with the grooves (8) of the embedded part (2) one by one, the blade wall and the embedded part (2) are fixed through the embedded screw rod (3), and the perpendicularity of the blade wall is adjusted; Eighth step: the side of the blade wall close to the ground wall (101) is connected in force with the ground wall (101); Ninth step: after the installation between the blade wall and the ground wall (101) is completed and is detected to be qualified, the last support (102) for supporting the layer is removed; Tenth step: the relevant work of the fifth step to the ninth step is repeated, and the construction is performed to the top plate, after the underground structure construction is completed and the maintenance reaches the design strength, the blade walls of the layers are removed and recycled layer by layer, and thus the whole support replacement construction of the foundation pit is completed.

2. The construction method of a precast assembled bracing blade wall of a foundation pit according to claim 1, wherein, The blade wall has two types, namely, a common prefabricated assembled blade wall (1) and a prestressed prefabricated assembled blade wall (11).

3. The construction method of a precast assembled bracing blade wall of a foundation pit according to claim 2, wherein, The ordinary prefabricated assembled blade wall (1) transmits force between the ground wall (101) by grouting, and after the ordinary prefabricated assembled blade wall (1) is hoisted, a tetrafluoroethylene friction-reducing plate (4) is installed on the side of the ordinary prefabricated assembled blade wall (1) close to the ground wall (101), the gap between the tetrafluoroethylene friction-reducing plate (4) and the ground wall (101) is blocked on both sides by using a common formwork to prevent grouting leakage during grouting, and then the gap between the tetrafluoroethylene friction-reducing plate (4) and the ground wall (101) is poured, thereby completing the construction of the structure bottom plate force transmission structure.

4. The construction method of a precast assembled bracing blade wall of a foundation pit according to claim 2, wherein, The prestressed prefabricated assembled blade wall (11) transmits force between the ground wall (101) by applying prestress by a hydraulic jack (13), and after the prestressed prefabricated assembled blade wall (11) is hoisted, the foot (12), the hydraulic jack (13), and the I-beam (14) are sequentially installed between the prestressed prefabricated assembled blade wall (11) and the ground wall (101), the I-beam (14) in contact with the ground wall (101) is stably connected to the hydraulic jack (13), the foot (12) of the hydraulic jack (13) is in flat contact with the prestressed prefabricated assembled blade wall (11), and then the hydraulic jack (13) is turned on, so that the axial force between the ground wall (101) and the blade wall reaches the same axial force as the supporting servo jack.

5. The construction method of a precast fabricated bracing blade wall of a foundation pit according to claim 1, wherein, The embedded part (2) of the blade wall is rigidly connected by the embedded screw rod (3) and the bottom plate reinforcement, the horizontal height of the embedded part (2) can be vertically adjusted by the embedded screw rod (3) before pouring concrete, so as to ensure the overall levelness of the embedded part (2), and the blade wall is arranged on both sides of each ground wall supporting beam with a horizontal distance of 2m from the supporting beam.

6. The construction method of a precast fabricated bracing blade wall of a foundation pit according to claim 1, wherein, Two screw rod lifting lugs (15) are welded at the upper end of the blade wall, and the two screw rod lifting lugs (15) are used as hoisting points for hoisting construction.

7. The construction method of a precast fabricated bracing blade wall of a foundation pit according to claim 1, wherein, During the embedding process of the embedded part (2), the embedded part (2) and the bottom clamping plate are fixed on the floor (106) by bolts, and the size of the bottom clamping plate is 4000mm in length, 540mm in width, and 20mm in thickness.

Images