Vertical diagonal bracing foundation pit supporting structure capable of being rapidly constructed

Abstract

The utility model discloses a vertical diagonal bracing foundation pit supporting structure capable of being rapidly constructed. The vertical diagonal bracing foundation pit supporting structure comprises a soil retaining assembly, a diagonal bracing assembly and a diagonal bracing foundation. The soil retaining assembly comprises a soil retaining support pile and a structural waist beam arranged on the soil retaining support pile; an embedded steel plate is arranged on the structural waist beam; the inclined strut assembly comprises an inclined strut plate, and one end of the inclined strut plate is connected with the embedded steel plate. The inclined strut foundation comprises an inclined strut and an inclined strut support arranged on the inclined strut, and a square steel plate cushion block is arranged on the inclined strut support; relates to the technical field of foundation pit supporting, and solves the problem of displacement control of foundation pit supporting in a limited area of a pulling anchor supporting system by arranging an inclined strut in a foundation pit to replace a traditional pulling anchor supporting system, and meanwhile, supporting can be provided in the excavation process. The vertical diagonal bracing system is made of a large amount of steel, and has the advantages of light dead weight, convenience in mounting and dismounting, immediate support effect after mounting, short maintenance time and construction speed obviously superior to that of concrete braces; and steel can be recycled after supporting is completed, and resource waste is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of foundation pit support, in particular to a fast-constructed vertical diagonal brace foundation pit support structure. Background Art

[0002] With the development of economy and the acceleration of urbanization, the construction requirements for foundation pit engineering are getting higher and higher. In the relevant technology, the displacement of foundation pit is often controlled by anchor support system. The anchor system includes free end and anchor section. The length of anchor cable is more than ten meters, which exceeds the existing construction land and is often prohibited from use due to over-limit. In addition, the construction process of anchor support system is complicated and there are difficulties such as long maintenance period.

[0003] The utility model with patent number CN216948305U discloses a foundation pit diagonal bracing structure, including a base buried in the soil, a bottom plate fixedly connected to the top surface of the base, a bracing plate rotatably connected to the bottom plate, and a bracing rod arranged between the bottom plate and the bracing plate, wherein a rotating assembly is arranged between the bottom plate and the bracing plate, and the rotating assembly includes a rotating shaft, two first rotating blocks fixedly connected to the side wall of the bottom plate, and a second rotating block fixedly connected to the side wall of the bracing plate, the rotating shaft is fixedly connected between the two first rotating blocks, and the second rotating block is rotatably connected to the rotating shaft; two fixing columns 12 are drilled into the soil, and the fixing plate 11 is buried in the soil, and the top surface of the fixing plate 11 is exposed outside the soil. The bottom plate 2 is placed on the fixing plate 11, the embedded bolt 111 passes through the fixing hole 21, and the embedded nut 112 is screwed on the end of the embedded bolt 111 away from the fixing plate 11, so that the bottom plate 2 can be stably installed on the fixing plate 11. Rotate the support plate 3 to adjust the angle between the support plate 3 and the base plate 2, slide the slider 231 and the fixed block 232 in the slide groove 22, and after adjusting the support angle of the diagonal support structure, pass the fastening bolt 234 through the movable groove 2321 and thread it into the connecting hole 24; in this patent, a supporting foundation is provided by drilling the fixed column 12 into the soil to provide a stable support for the support plate 3, but in the process of foundation pit support, the method adopted is to excavate a section and support a section, and the fixed column 12 is fixed in the foundation pit, which affects the excavation of the foundation pit. At the same time, as the soil in the foundation pit is excavated, the supporting capacity of the fixed column 12 decreases, which can easily cause the support plate to slip, thereby causing the foundation pit to collapse. Utility Model Content

[0004] The main purpose of the utility model is to provide a fast-constructed vertical diagonal bracing foundation pit supporting structure, which is used to solve the problem that the supporting capacity of the existing foundation pit supporting device decreases during the supporting process, which easily causes the foundation pit to slide and collapse.

[0005] To achieve the above-mentioned purpose, the utility model provides a fast-constructed vertical diagonal bracing foundation pit support structure, comprising:

[0006] The retaining assembly comprises a plurality of groups of retaining support piles arranged at intervals on the edge of the foundation pit, and a structural waist beam arranged on the retaining support piles; the retaining support piles are provided with a connecting crown beam; the structural waist beam is obliquely arranged on the retaining support piles so that a formwork angle is formed between the structural waist beam and the horizontal plane; the structural waist beam is provided with a pre-buried steel plate;

[0007] The diagonal brace foundation comprises diagonal brace pillars arranged at intervals on the opposite sides of the retaining support piles, and diagonal brace supports arranged on the diagonal brace pillars; the diagonal brace supports connect multiple groups of diagonal brace pillars to form a whole, and a steel plate pad is arranged on the diagonal brace supports;

[0008] The diagonal brace assembly comprises a diagonal brace plate; one end of the diagonal brace plate is connected to the embedded steel plate, and the other end is connected to the steel plate pad; the end of the diagonal brace plate connected to the embedded steel plate is higher than the end connected to the steel plate pad.

[0009] As a further improvement of the utility model, the structural waist beam includes anchor steel bars arranged in the retaining support piles, a steel mesh connected to the anchor steel bars, and a concrete pier cast around the steel mesh; the anchor steel bars are arranged in multiple groups at intervals; and the embedded steel plate is fixedly connected to the steel mesh.

[0010] As a further improvement of the utility model, the top end of the diagonal brace pillar exceeds the bottom end of the foundation pit by more than 1m; the diagonal brace support is close to the diagonal brace pillar.

[0011] As a further improvement of the utility model, the embedded steel plate is fixedly connected to the end face of the structural waist beam facing the foundation pit; the embedded steel plate and the bottom support formwork angle of the structural waist beam.

[0012] As a further improvement of the utility model, the diagonal bracing plates are arranged in groups of two, and the end surfaces where the diagonal bracing plates are connected to the steel plate pads are provided with inclined surfaces.

[0013] The beneficial effects of the utility model are embodied in:

[0014] By setting diagonal braces in the foundation pit to replace the traditional anchor support system, the problem of foundation pit support displacement control in the restricted area of ​​the anchor support system is solved, and support can be provided during the excavation process; the vertical diagonal bracing system uses a large amount of steel, which has the characteristics of light weight, easy installation and dismantling, and immediate support after installation, short maintenance time, and the construction speed is significantly better than concrete bracing; the steel can be recycled and reused after the support is completed, reducing resource waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a front structural schematic diagram of a fast-constructed vertical diagonal bracing foundation pit support structure of the utility model;

[0016] Figure 2It is a top view of a fast-constructed vertical diagonal bracing foundation pit support structure of the utility model;

[0017] Figure 3 It is a schematic diagram of the diagonal brace pillars of a vertical diagonal brace foundation pit support structure for rapid construction according to the utility model;

[0018] Figure 4 It is a schematic diagram of the structural waist beam of a vertical diagonal bracing foundation pit supporting structure for rapid construction of the utility model;

[0019] Description of reference numerals:

[0020] 1. Retaining support piles; 2. Structural waist beam; 201. Anchor steel bars; 202. Steel mesh; 203. Concrete piers; 3. Embedded steel plates; 4. Diagonal brace plates; 5. Diagonal brace pillars; 6. Diagonal brace supports; 7. Steel plate pads; 8. Connecting crown beams; 9. Formwork angle; 10. Reserved soil under the diagonal brace. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0022] In one embodiment, see Figure 1 The utility model discloses a fast-constructed vertical diagonal brace foundation pit supporting structure, which comprises a retaining assembly, a diagonal brace foundation and a diagonal brace assembly.

[0023] Among them, the retaining assembly includes a plurality of groups of retaining support piles 1 arranged at intervals on the edge of the foundation pit, and a structural waist beam 2 arranged on the retaining support piles 1; a connecting crown beam 8 is provided on the retaining support pile 1; the structural waist beam 2 is obliquely arranged on the retaining support pile 1 so that a formwork angle 9 is formed between the structural waist beam 2 and the horizontal plane, and a pre-embedded steel plate 3 is provided on the structural waist beam 2; the diagonal brace foundation includes diagonal brace pillars 5 arranged at intervals on the opposite sides of the retaining support piles 1, and a diagonal brace support 6 arranged on the diagonal brace pillars 5, the diagonal brace support 6 connects a plurality of groups of diagonal brace pillars 5 to form a whole, and a steel plate pad 7 is provided on the diagonal brace support 6; the diagonal brace assembly includes a diagonal brace plate 4, one end of the diagonal brace plate 4 is connected to the pre-embedded steel plate 3, and the other end is connected to the steel plate pad 7, and the end of the diagonal brace plate 4 connected to the pre-embedded steel plate 3 is higher than the end connected to the steel plate pad 7.

[0024] Preferably, the retaining support piles 1 are reinforced concrete cast-in-place piles, and the connecting crown beams 8 are reinforced concrete structures.

[0025] In the above arrangement, rotary drilling or long spiral drilling is used to pre-drill holes at the edge of the foundation pit for constructing retaining support piles 1, and the concrete at the pile head of the retaining support pile 1 is chiseled off. After chiseling off, the pile head elevation is the bottom elevation of the connecting crown beam 8, and the concrete connecting crown beam 8 is constructed. The concrete connecting crown beam 8 is connected to the exposed steel bars at the pile head of the concrete retaining support pile 1 to form a whole.

[0026] For further information, see Figure 4 The structural waist beam 2 includes an anchor steel bar 201 arranged in the retaining support pile 1, a steel mesh 202 connected to the anchor steel bar 201, and a concrete pier 203 cast on the periphery of the steel mesh 202; multiple groups of anchor steel bars 201 are arranged at intervals, and the embedded steel plate 3 is fixedly connected to the steel mesh 202.

[0027] Preferably, four groups of anchor steel bars 201 are arranged on each group of retaining support piles 1 .

[0028] Preferably, the structural waist beam 2 is constructed by planting reinforcement and grouting on the side of the retaining support pile 1 close to the foundation pit.

[0029] Preferably, the embedded steel plate 3 is square, 900mmx900mm, and 20mm thick.

[0030] In the above arrangement, the top part of the retaining support pile 1 is chiseled out to construct the crown beam, the foundation pit is excavated in layers and sections, the structural waist beam 2 is constructed when the structural waist beam 2 is dug, and then the foundation pit is excavated downwards to reserve the soil 10 under the diagonal support; holes are opened on the retaining support pile 1, 4 φ25 steel bars are implanted on each retaining support pile 1, and cement slurry is injected, with a water-cement ratio of 0.5 to 0.55 and a grouting pressure of not less than 0.6MPa. The steel mesh 202 is tied, the embedded steel plate 3 is installed, the formwork is installed, and the concrete is poured.

[0031] For further information, see Figure 3 The top of the diagonal brace support 5 exceeds the bottom of the foundation pit by more than 1m; the diagonal brace support 6 is close to the diagonal brace support 5.

[0032] Preferably, the length of the retaining support is greater than 20 m, and the length of the diagonal support pillar 5 is greater than 12 m.

[0033] Preferably, the diagonal brace pillars 5 and the diagonal brace supports 6 are both made of H-shaped steel.

[0034] In the above arrangement, H-shaped steel is mechanically pressed into the ground as diagonal bracing support 5, a steel beam is arranged in front of the H-shaped steel as diagonal bracing support 6, and the diagonal bracing support 6 and the part of the diagonal bracing support 5 exposed above the ground are fixed by welding.

[0035] For further information, see Figure 4The embedded steel plate 3 is fixedly connected to the end face of the structural waist beam 2 facing the foundation pit, and the bottom support angle between the embedded steel plate 3 and the structural waist beam 2 is 9.

[0036] Preferably, the formwork angle 9 is 114°; when constructing the concrete structure waist beam 2, attention should be paid to the formwork angle at the diagonal support end. The setting of the formwork angle 9 facilitates the subsequent construction of the support plate to ensure the connection stability of the support plate, thereby improving the overall support capacity.

[0037] For further information, see Figure 2 The diagonal bracing plates 4 are arranged in groups of two, and the end faces where the diagonal bracing plates 4 are connected to the steel plate pads 7 are provided with inclined surfaces.

[0038] Preferably, the diagonal brace plate 4 is made of double-jointed H-shaped steel, the diagonal brace plate 4 is welded at intervals of 2m along the joint position, the weld length is 500mm, and the weld length at both ends of the diagonal brace plate 4 is 1m.

[0039] Preferably, the H-shaped steel model is RZ-HN700x300 and the material is Q345.

[0040] Preferably, the steel plate pad 7 has a size of 800mmX800mm and a plate thickness of 10mm.

[0041] Preferably, the arrangement position of the diagonal bracing columns should be adapted to the post-cast zone of the building structure, so as to facilitate the pulling out of the diagonal bracing foundation columns at the end of the foundation pit construction.

[0042] In the above setting, the length of the diagonal brace plate 4 is determined according to the designed foundation pit size and the diagonal brace position, and one end of the diagonal brace plate 4 is cut to form a slope. After the two groups of diagonal brace plates 4 are welded, they are respectively welded to the embedded steel plate 3 and the steel plate pad 7. The diagonal brace plate 4 is located above the soil 10 under the reserved diagonal brace. After the installation of the diagonal brace plate 4 is completed, the soil 10 under the reserved diagonal brace is excavated.

[0043] In this embodiment, the retaining structure adopts support piles, which are drilled by rotary drilling or long spiral. Then the pile head is chiseled off to construct the crown beam diagram, and the foundation pit is excavated in layers and sections. When the structural waist beam 2 is dug, the structural waist beam 2 is constructed. When the foundation pit is excavated downward, the soil 10 under the diagonal brace is reserved. When constructing the diagonal brace foundation, the steel section is pressed into the ground by machinery, and a steel section crossbeam is set in front of the steel section as a diagonal brace support 6. Finally, the diagonal brace member and the square steel plate pad 7 between the diagonal brace support 6 and the diagonal brace are installed, and the reserved diagonal brace soil 10 is excavated. At this point, the foundation pit support structure is completed.

[0044] After the foundation pit site is leveled, a retaining support pile 1 is formed by mechanical drilling, lowering a steel cage, and pouring concrete. The retaining support pile 1 is over-poured beyond the design elevation by 1m to ensure that the quality of the retaining support pile 1 is not affected after the concrete exceeding the design elevation is chiseled out. The concrete connecting crown beam 8 is constructed, and the concrete connecting crown beam 8 is connected to the exposed steel bars of the pile head of the concrete retaining support pile 1 to form a whole.

[0045] When the curing strength of the crown beam reaches the standard, an excavator is used to dig the original soil in the foundation pit to the location of the structural waist beam 2. The drilling and grouting method is used to implant 4 φ25 steel bars on each support pile, and cement slurry is injected with a water-cement ratio of 0.5-0.55 and a grouting pressure of not less than 0.6MPa. Tie the steel bars of the structural waist beam 2, install the embedded steel plate 3, install the formwork, and pour the concrete. When constructing the concrete structural waist beam 2, attention should be paid to the angle of the formwork at the diagonal support end. In this case, 114° is selected.

[0046] During the construction and maintenance of the waist beam, excavation can be carried out in the foundation pit to reserve soil under the diagonal support. When the soil outside the diagonal support pillar 5 is excavated to the bottom of the foundation pit, the diagonal support pillar 5 is constructed, and the H-shaped steel is driven into the soil with a hydraulic vibration hammer. The diagonal support pillar 5 must ensure that it is 1.0m above the bottom of the pit. An H-shaped steel crossbeam is placed on the side of the diagonal support pillar 5 close to the supporting structure to form a diagonal support seat 6.

[0047] After the construction of the diagonal bracing pillars 5 of the entire site is completed, the prepared diagonal bracing plate 4 is installed. The diagonal bracing plate 4 is installed manually with a small crane. Before installation, a 800X800 steel plate pad 7 is placed at the end of the diagonal bracing support 6, and then the diagonal bracing plate 4 is installed. The diagonal bracing plate 4 should ensure that both ends are tight, and one end of the structural waist beam 2 is welded firmly to the diagonal bracing plate 4 with electric welding. After the installation of the diagonal bracing components is completed, the soil below the reserved diagonal bracing can be excavated.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fast-constructed vertical diagonal bracing foundation pit support structure, characterized in that: include: The retaining assembly comprises a plurality of groups of retaining support piles (1) arranged at intervals on the edge of a foundation pit, and a structural waist beam (2) arranged on the retaining support piles (1); the retaining support piles (1) are provided with a connecting crown beam (8); the structural waist beam (2) is arranged obliquely on the retaining support piles (1) so that a formwork angle (9) is formed between the structural waist beam (2) and a horizontal plane; and the structural waist beam (2) is provided with a pre-buried steel plate (3); The diagonal brace foundation comprises diagonal brace pillars (5) arranged at intervals on the opposite sides of the retaining support piles (1), and diagonal brace supports (6) arranged on the diagonal brace pillars (5); the diagonal brace supports (6) connect multiple groups of diagonal brace pillars (5) to form a whole, and a steel plate pad (7) is arranged on the diagonal brace supports (6); The diagonal brace assembly comprises a diagonal brace plate (4); one end of the diagonal brace plate (4) is connected to the embedded steel plate (3), and the other end is connected to the steel plate pad (7); the end of the diagonal brace plate (4) connected to the embedded steel plate (3) is higher than the end connected to the steel plate pad (7).

2. A fast-constructed vertical diagonal bracing foundation pit support structure according to claim 1, characterized in that: The structural waist beam (2) comprises anchor steel bars (201) arranged in the retaining support pile (1), a steel mesh (202) connected to the anchor steel bars (201), and a concrete pier (203) cast on the periphery of the steel mesh (202); a plurality of groups of anchor steel bars (201) are arranged at intervals; and the embedded steel plate (3) is fixedly connected to the steel mesh (202).

3. A fast-constructed vertical diagonal bracing foundation pit support structure according to claim 2, characterized in that: The top end of the diagonal brace support (5) exceeds the bottom end of the foundation pit by more than 1m; the diagonal brace support (6) is close to the diagonal brace support (5).

4. A fast-constructed vertical diagonal bracing foundation pit support structure according to claim 3, characterized in that: The embedded steel plate (3) is fixedly connected to the end surface of the structural waist beam (2) facing the foundation pit; the embedded steel plate (3) and the bottom end formwork angle (9) of the structural waist beam (2) are formed.

5. A fast-constructed vertical diagonal bracing foundation pit support structure according to claim 4, characterized in that: The diagonal support plates (4) are arranged in groups of two, and the end surfaces of the diagonal support plates (4) connected to the steel plate pads (7) are provided with inclined surfaces.

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