CN216075159U

CN216075159U - Safety device for local pit of foundation pit

Info

Publication number: CN216075159U
Application number: CN202122662768.3U
Authority: CN
Inventors: 宁晋文; 张会亮
Original assignee: Shanghai Baoye Municipal Engineering Co ltd; Shanghai Baoye Group Corp Ltd
Current assignee: Shanghai Baoye Municipal Engineering Co ltd; Shanghai Baoye Group Corp Ltd
Priority date: 2021-11-02
Filing date: 2021-11-02
Publication date: 2022-03-18
Anticipated expiration: 2031-11-02

Abstract

The utility model discloses a safety device for a local pit of a foundation pit, which comprises: the foundation pit supporting structure comprises a bottom plate, a reinforcing bar cushion layer used for increasing the supporting strength of the bottom plate, shaping pieces used for opening opposite two sides of a local pit and enclosure row piles used for preventing a foundation pit from collapsing, wherein the shaping pieces are pre-buried in the upper portion of the local pit and connected with the reinforcing bar cushion layer, the bottom plate is arranged on the reinforcing bar cushion layer, the reinforcing bar cushion layer is arranged around the periphery of the local pit and connected with the edges of the enclosure row piles, and concrete is poured on the bottom plate. By using the safety device for the local pit of the foundation pit, provided by the utility model, the continuous deformation of deep soil body for enclosing the row piles can be effectively avoided, the earthwork excavation safety of the local pit is ensured, the whole construction sequence and speed of the foundation bottom plate are not influenced, and the safety and construction effect of the earthwork excavation of the local pit can be effectively improved.

Description

Safety device for local pit of foundation pit

Technical Field

The utility model relates to the technical field of house construction, in particular to a safety device for a local pit of a foundation pit.

Background

At present, in the construction of urban building foundation pit engineering, a containment system mainly plays key roles of ensuring the safety and stability of the foundation pit and limiting collapse. In the excavation process of the foundation pit earthwork, displacement disturbance is inevitably generated on the side wall of the foundation pit due to stress release and a cavitation effect. At the moment, the earthwork deformation of the side wall of the foundation pit is limited mainly by the enclosure row piles and the concrete support system. And when the horizontal lateral displacement, the vertical displacement and the like of the enclosure row piles exceed the warning values, the foundation pit is in a danger alarm state. In the excavation process of the earthwork of the large area of the building foundation pit, the foundation pit enclosure deformation mostly tends to increase the state, local pit excavation such as a local elevator shaft and a water collecting well is performed at the moment, especially the local pit around the enclosure row pile will aggravate the deformation rate of the foundation pit undoubtedly, the instability risk of the foundation pit is increased, the excavation opportunity, the excavation condition, the excavation sequence and the like of the local pit earthwork are not properly processed, and the foundation pit will be abnormally dangerous.

Usually, in order to improve the safety of excavation of a local pit of a foundation pit, larsen steel sheet piles are added for temporary enclosure, but when the soil quality of the foundation pit is poor and the horizontal displacement of the deep layer of the enclosure row piles after earthwork excavation is large, the mode cannot ensure the displacement deformation and the safety of the enclosure row piles after the local pit excavation. Moreover, when the local deep pit enclosure is constructed by steel sheet piles such as Larsen steel sheet piles and channel steel, secondary reverse transportation of piling machinery needs to be carried out on the bottom plate of the foundation pit, the Larsen steel sheet piles and the like need to be pulled out after construction is finished, the construction progress of the bottom plate can be influenced, and the coordination quantity of personnel, machinery and material organization is large, and time and labor are wasted.

In summary, how to improve the safety and the construction effect of local pit earthwork excavation is a problem to be solved urgently by those skilled in the art at present.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention is directed to a safety device for a local pit of a foundation pit, which can improve the safety and construction effect of earth excavation of the local pit.

In order to achieve the above purpose, the utility model provides the following technical scheme:

a safety device for a partial pit of a foundation pit, comprising: the bottom plate, be used for the increase the arrangement of reinforcement bed course of the support intensity of bottom plate, the setting member that is used for strutting the relative both sides in local pit and be used for preventing the enclosure campshed that the foundation ditch collapses, the setting member pre-buries in the upper portion in local pit, and with the arrangement of reinforcement bed course is connected, the bottom plate is located on the arrangement of reinforcement bed course, the arrangement of reinforcement bed course centers on week portion setting in local pit, and with the edge connection of enclosure campshed, concrete has been pour on the bottom plate.

Preferably, the reinforcing bar cushion layer comprises double-layer reinforcing bars and concrete for pouring and filling the double-layer reinforcing bars.

Preferably, the thickness of the reinforcing steel cushion layer is not less than 300mm, and the concrete strength of the reinforcing steel cushion layer is not less than C20.

Preferably, the fixed part is H-shaped steel.

Preferably, the reinforcing bar cushion layer is provided with a steel end plate used for being connected with the end part of the H-shaped steel.

Preferably, the steel end plate and the H-shaped steel are welded and fixed.

Preferably, the enclosure gang piles comprise cast-in-situ bored piles and concrete support beams.

Preferably, the outer side of the enclosure row piles is provided with a triaxial mixing pile waterproof curtain.

When the safety device for the local pit of the foundation pit provided by the utility model is used, a layer of reinforcement cushion layer can be laid on the periphery of the local pit in advance, the reinforcement cushion layer and the bottom plate are connected into a whole, and the reinforcement cushion layer at the local pit can be poured to the edge of the enclosure row pile to form a rigid connection support-changing belt with the enclosure row pile. Later, pre-buried the type piece at local pit upper portion to make the type piece be connected with the arrangement of reinforcement bed course, thereby the type piece forms the stable biography power area in local pit, avoids the both sides of local pit to appear warping and collapsing.

After the construction of the reinforcement cushion layer and the shaping piece of the local deep pit is completed and the reinforcement cushion layer and the shaping piece are connected with the enclosure row piles of the foundation pit in an effective rigid support-changing mode, the bottom plate concrete pouring construction near the deep pit can be carried out. In order to ensure the safety of the foundation pit enclosure, when the foundation slab around the pit reaches the design strength of 80%, and the deformation stability of the foundation pit enclosure is detected, the soil body of the local pit can be excavated in layers, the fixed part is not required to be removed during excavation, and the fixed part is removed after the pit excavation is finished. The device can effectively avoid continuous deformation of deep soil bodies of the enclosing row piles, guarantees the earthwork excavation safety of local deep pits, and does not influence the whole construction sequence and speed of the foundation slab.

In conclusion, the safety device for the local pit of the foundation pit provided by the utility model can improve the safety and the construction effect of the local pit earthwork excavation.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a safety device for a local pit of a foundation pit provided by the utility model;

FIG. 2 is a schematic structural view of a base plate and a reinforcing mat;

FIG. 3 is a schematic structural view of the stationary member;

fig. 4 is a schematic structural view of a steel end plate.

In fig. 1-4:

the waterproof curtain comprises a bottom plate 1, a reinforcing mat layer 2, a fixed piece 3, an enclosure row pile 4, a local pit 5, a steel end plate 6 and a triaxial mixing pile 7.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The core of the utility model is to provide a safety device for the local pit of the foundation pit, which can improve the safety and the construction effect of the local pit earthwork excavation.

Referring to fig. 1 to 4, fig. 1 is a schematic structural diagram of a safety device for a local deep pit of a foundation pit according to the present invention; FIG. 2 is a schematic structural view of a base plate and a reinforcing mat; FIG. 3 is a schematic structural view of the stationary member; fig. 4 is a schematic structural view of a steel end plate.

This embodiment provides a safety device of local pit in foundation ditch, includes: the bottom plate 1, a reinforcement cushion 2 for increasing the support intensity of bottom plate 1, a setting member 3 for strutting the relative both sides of local pit 5 and be used for preventing the enclosure campshed 4 that the foundation ditch collapses, setting member 3 pre-buries in the upper portion of local pit 5, and is connected with reinforcement cushion 2, bottom plate 1 is located on reinforcement cushion 2, reinforcement cushion 2 sets up around the week portion of local pit 5, and with the edge connection of enclosure campshed 4, concrete has been pour on the bottom plate 1.

In the actual application process, the shapes, structures, sizes, positions, materials and the like of the bottom plate 1, the reinforcement cushion layer 2, the shaping piece 3 and the enclosure row piles 4 can be determined according to actual conditions and actual requirements.

When the safety device for the local pit of the foundation pit provided by the utility model is used, a layer of reinforcement cushion layer 2 can be laid on the periphery of the local pit 5 in advance, the reinforcement cushion layer 2 and the bottom plate 1 are connected into a whole, and the reinforcement cushion layer 2 at the local pit 5 can be poured to the edge of the enclosure row piles 4 so as to form a rigid connection support-changing belt with the enclosure row piles 4. Afterwards, pre-buried forming element 3 in local pit 5 upper portion to make forming element 3 be connected with arrangement of reinforcement bed course 2, thereby forming the stable biography power area in local pit 5 in forming element 3, avoid local pit 5's both sides to appear deforming and collapsing.

After the construction of the reinforcement cushion layer 2 and the shaping piece 3 of the local deep pit 5 is completed and the effective rigid support-changing connection is formed with the enclosure row piles 4 of the foundation pit, the concrete pouring construction of the bottom plate 1 near the deep pit can be carried out. In order to ensure the safety of the foundation pit enclosure, when the foundation slab 1 around the pit reaches the design strength of 80%, and the deformation stability of the foundation pit enclosure is detected, the soil body of the local pit 5 can be excavated in layers, the fixed part 3 does not need to be removed during excavation, and the fixed part 3 is removed after the pit excavation is finished. The device can effectively avoid continuous deformation of the deep soil body of the enclosing row piles 4, guarantee the earthwork excavation safety of the local deep pit 5 and does not influence the whole construction sequence and speed of the foundation slab 1.

In conclusion, the safety device for the local pit of the foundation pit provided by the utility model can improve the safety and the construction effect of the earth excavation of the local pit 5.

On the basis of the above embodiment, preferably, the reinforcing steel bar cushion layer 2 comprises double-layer steel bars and concrete for pouring and filling the double-layer steel bars, so that the supporting strength of the reinforcing steel bar cushion layer 2 is improved, and construction and manufacturing are facilitated.

Preferably, the thickness of the reinforced cushion layer 2 is not less than 300mm, and the concrete strength of the reinforced cushion layer 2 is not less than C20.

It should be noted that, a reinforcing steel bar layer with a thickness not less than 300mm may be laid around the local pit 5, and then concrete may be poured into the reinforcing steel bar layer to form a reinforced concrete cushion layer, the concrete strength of the cushion layer is not less than C20, the reinforcing steel bar layer may include a double-layer reinforcing steel bar with a diameter of phi 12 and a distance of 150mm, the reinforced concrete cushion layer 2 and the cushion layer of the bottom plate 1 may be connected into a whole, and the reinforced concrete cushion layer 2 at the local pit 5 may be poured to the edge of the enclosure row piles 4 to form a rigid connection support-changing belt with the enclosure row piles 4.

Preferably, the shaping member 3 is H-shaped steel. The H-shaped steel can be embedded in the upper portion of the local pit 5 in a welded mode and embedded in the reinforcement cushion layer 2, and therefore the local pit 5 forms a stable force transmission belt. The H-section steel may be provided as H400 × 13 × 21 section steel, that is, the H-section steel has a width of 400mm, a height of 400mm, a web thickness of 13mm, and a flange thickness of 21 mm.

On the basis of the above embodiment, preferably, the reinforcement mat 2 is provided with a steel end plate 6 connected with the end of the H-shaped steel to ensure that the H-shaped steel is stably fixed in the local pit 5, so as to effectively open opposite sides of the local pit 5 and avoid the collapse and deformation phenomenon in the local pit 5.

Preferably, the steel end plate 6 and the H-shaped steel are welded and fixed, so that the connection effect of the H-shaped steel and the reinforcement cushion layer 2 is ensured, and the H-shaped steel is prevented from moving in the local deep pit 5.

Preferably, the containment raft 4 comprises cast-in-situ bored piles and concrete support beams. The cast-in-situ bored pile is matched with the concrete supporting beam to ensure the safety and stability of the foundation pit and limit collapse. During the excavation of the earthwork of the foundation pit, the deformation of the earthwork on the side wall of the foundation pit can be effectively limited.

Preferably, the outer side of the enclosure row piles 4 is provided with a triaxial mixing pile waterproof curtain 7, and the triaxial mixing pile waterproof curtain 7 can form an integral stress support system with the cast-in-situ bored piles and the concrete support beams so as to ensure the safety and stability of the foundation pit.

In order to further explain the method for using the safety device for the partial pit of the foundation pit provided by the utility model, the following description is given by way of example.

Before excavation operation is carried out, a reinforcement cushion layer 2 is laid on the periphery of a local pit 5 to the side of an enclosure row pile 4 in advance to form a local support-changing force-transmitting belt, H-shaped steel is pre-embedded in the reinforcement cushion layer 2 to enable the upper portion of the local pit 5 to form effective support, after the concrete strength of a peripheral bottom plate 1 reaches 80% of design strength, the local pit 5 on the side of the enclosure row pile 4 is excavated in a layered mode, continuous deformation of a deep soil body of the enclosure row pile 4 is effectively avoided, and earth excavation safety of the local pit 5 is guaranteed. Compared with methods for synchronously excavating local deep pits 5 and constructing and driving Larsen steel sheet pile enclosures and the like, the method has the advantages that the whole construction sequence and speed of the foundation slab 1 are not influenced, the earth excavation safety of the foundation pit is ensured, the whole streamlined construction can be realized, and the secondary scheduling and extra emergency measure cost of the foundation pit caused by the change of the earth excavation sequence is reduced.

After the construction of the additional cushion layer of the local pit 5 and the H-shaped steel is finished, effective rigid support-changing connection can be formed between the additional cushion layer and the enclosure row piles 4 of the foundation pit, and then the construction of the foundation large bottom plate 1 near the pit can be carried out. In order to ensure the safety of foundation pit enclosure, after the foundation slab 1 around the pit reaches the design strength of 80%, and the stability of the foundation pit enclosure deformation is monitored, the soil body of the local pit 5 is excavated in a layered mode, H-shaped steel is not removed during excavation, and after the pit excavation is completed and the concrete pouring operation of a collecting well (elevator shaft) is finished, the H-shaped steel is removed.

It should be noted that the application has been applied to Shanghai Yangxi Zhi Kangfu hospital, and the basement foundation pit area of the Shanghai Yangxi Zhi Kangfu hospital is about 26000m²The perimeter of the foundation pit is about 760m, the excavation depth of the foundation pit is 5.75 m-6.50 m, and the foundation pit enclosure adopts a cast-in-situ bored pile and a triaxial cement soil mixing pile as a soil retaining and water stopping curtain. The excavation depth of the local pit 5 of the fire-fighting water collecting well is 7.8-9.7 m, the depth of the drop depth of the local pit 5 of the fire-fighting water collecting well is 1.9-3.8 m, the form of a support belt is changed by adopting local support and a reinforcement cushion layer 2, and after the concrete strength of the bottom plate 1 reaches 80% of the design strength, excavation of the local pit 5 is carried out, so that the potential safety hazard of a foundation pit caused by construction of the local pit 5 is effectively reduced, and the safety of excavation of the earth is ensured.

It should be noted that the directions and positional relationships indicated in the present application, such as "up and down" and the like, are based on the directions and positional relationships shown in the drawings, and are only for the convenience of simplifying the description and facilitating the understanding, but do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the present invention.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. Any combination of all the embodiments provided by the present invention is within the scope of the present invention, and will not be described herein.

The safety device for the local pit of the foundation pit provided by the utility model is described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims

1. A safety device for a partial pit of a foundation pit, comprising: the foundation pit supporting structure comprises a base plate (1), a reinforcement cushion layer (2) for increasing the supporting strength of the base plate (1), a shaping piece (3) for opening the two opposite sides of a local pit (5) and a support row pile (4) for preventing a foundation pit from collapsing, wherein the shaping piece (3) is pre-embedded in the upper part of the local pit (5) and connected with the reinforcement cushion layer (2), the base plate (1) is arranged on the reinforcement cushion layer (2), the reinforcement cushion layer (2) surrounds the periphery of the local pit (5) and is connected with the edge of the support row pile (4), and concrete is poured on the base plate (1).

2. A safety arrangement for a partial pit of a foundation pit according to claim 1, wherein the reinforcement mat (2) comprises double layers of steel reinforcement and concrete for casting the double layers of steel reinforcement.

3. A safety device for a partial pit of foundation pit according to claim 2, wherein the thickness of the reinforcing mat (2) is not less than 300mm, and the strength of the concrete of the reinforcing mat (2) is not less than C20.

4. A safety device for a partial pit of a foundation pit according to any one of claims 1 to 3, characterized in that the shaped piece (3) is H-section steel.

5. A safety arrangement for a partial pit of a foundation pit according to claim 4, wherein the reinforcement mat (2) is provided with steel end plates (6) for connection with the ends of the H-section steel.

6. A safety device for a partial pit of a foundation pit according to claim 5, characterized in that the steel end plate (6) and the H-beam are welded.

7. A safety device for a foundation pit partial pit according to any one of claims 1 to 3, characterized in that the containment row of piles (4) comprises cast-in-situ bored piles and concrete support beams.

8. A safety device for a partial pit of a foundation pit according to claim 7, wherein the outer side of the enclosure row piles (4) is a triaxial mixing pile waterproof curtain (7).