CN204715364U - A kind of foundation pit support device - Google Patents

Abstract

The utility model relates to a support device for a foundation pit, which belongs to the technical field of building structure construction, and comprises crown beam corbels set on peripheral support piles and bottom plate corbels set on the top surface of a basement foundation floor, and crown beam corbels and The double H-shaped steel set between the corbels of the bottom plate, the foundation pit support device is suitable for the construction of non-circular large-area irregular deep foundation pits with support piles around the foundation pit, combining the constructed support piles with the underground The structure (pile + basement floor) forms a "belt" support structure in the pit parallel to the support body, which effectively avoids the disadvantages of high support cost and long construction period of the traditional concrete internal support system, and reduces the cost of the support system , suitable for large-area deep foundation pits in basements with 1 to 2 floors.

Description

A foundation pit support device

technical field

The utility model relates to a support device for foundation pits, which belongs to the technical field of building structure construction, and is especially suitable for large-area irregular deep foundation pit projects with built-up enclosure structures around and requiring internal support.

Background technique

The foundation pit support is to ensure the safety of the underground structure construction and the surrounding environment of the foundation pit, and the support, reinforcement and protection measures are adopted for the side wall of the foundation pit and the surrounding environment. Common foundation pit support types mainly include row pile support, underground diaphragm wall support, cement retaining wall, steel sheet pile, soil nail wall, foundation pit support or a combination of two or more.

For the traditional foundation pit support technology, if the soil quality of the foundation pit is poor and the excavation of the foundation pit is relatively deep, especially when the plane size of the foundation pit is relatively large, if the common concrete internal support form is used, the cost of support measures will be relatively high. High, the construction period is relatively long, and the way of internal support will make the foundation pit densely packed, which is inconvenient for construction. For example, the Chinese utility model patent application whose publication number is CN101892667 discloses a foundation pit support device and a construction method, which comprehensively adopts both of the SMW construction method pile system, the internal support system, the concrete slope protection system and the soil nail wall slope protection system. The combination of the above two is not only suitable for the support of large-area foundation pits, but also effectively reduces the cost and cost of foundation pit support. However, it is not suitable for projects with complex soil stratification and groundwater conditions in the surrounding sites.

Utility model content

The purpose of the utility model is to overcome the above technical problems, provide a project suitable for large-area foundation pit support, and the surrounding soil stratification and site groundwater conditions are complex, and effectively reduce the cost and cost of foundation pit support.

The above-mentioned technical purpose of the utility model is achieved through the following technical solutions:

A support device for a foundation pit, comprising crown beam corbels set at the top of peripheral support piles, steel purlins set below the crown beam corbels near the top, and bottom plate corbels set on the top surface of the basement bottom plate , the bottom plate corbel is anchored into the bottom plate. Insert double H-shaped steel into the support pile, and the length of the inserted steel in the pile body is equal. One end of one pair of H-shaped steel is supported on the steel purlin, and the other end is supported on the corbel of the bottom plate; the other end of the double H-shaped steel is supported on the corbel of the crown beam, and the other end is supported on the corbel of the bottom plate.

Preferably, the pit-facing surface of the crown beam corbel is oblique to the pre-embedded steel plate and reinforcement mesh, and H-shaped steel is arranged perpendicular to the steel plate.

As a preference, the back pit surface of the corbel of the bottom plate is oblique to the pre-embedded steel plate and reinforcement mesh, and H-shaped steel is arranged perpendicular to the steel plate.

Preferably, the floor corbel back pit surface includes a vertical floor section perpendicular to the basement foundation floor and an oblique connecting section obliquely connected to the vertical floor section, and the vertical floor section and the oblique The connecting sections are all vertically provided with H-shaped steel.

In summary, the foundation pit support implementation method carried out using the foundation pit support device described in the utility model is suitable for large-area deep piles that have been constructed in three directions in the surrounding environment and have no support in one direction. The construction of the foundation pit project effectively avoids the disadvantages of high support cost and long construction period of the traditional concrete internal support system, and reduces the cost of the support system. It is suitable for projects with surrounding soil stratification and complex groundwater conditions.

Description of drawings

Fig. 1 is the structural representation of the utility model foundation pit supporting device;

Fig. 2 is the enlarged schematic diagram of crown beam corbel;

Figure 3 is an enlarged schematic view of the base plate corbel;

In the figure, 1. Peripheral support piles; 2. Crown beam corbels; 3. Bottom plate corbels; 4. Steel purlins; 5. Basement foundation floor; 6. Double H-shaped steel; 7. Steel plates; ; 9, H-shaped steel.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described in further detail.

A typical implementation project using this utility model: the project site area is 14,000 square meters, the construction area is 10,300 square meters, the circumference of the foundation pit is about 350 meters, the part including the support pile is 270 meters, the earth excavation is 20,000 cubic meters, and the soil quality is sand. Mainly, it is specifically divided into 6 layers, and the engineering characteristic indexes of foundation soil layered from top to bottom are as follows:

The storey height is 3.8m-6.0m, the foundation form is a piled raft foundation, the thickness of the raft is 400mm-500mm; the thickness of the roof is 150mm-200mm, and there are 25 precipitation wells with a depth of 20m. Supporting piles have been constructed around the foundation pit of this project. The straight-line distance from the foundation pit to the sea is about 100 meters, and the groundwater level is about 1 meter deep. The type of groundwater mainly exists in the sandy soil layer without pressure bearing, and the buried depth of the water head is about 5 meters. It is closely connected with the regional marine water body, and the water volume is abundant, which has a great impact on the construction and maintenance of underground projects.

As shown in Figure 1, a foundation pit support device includes a peripheral support pile 1, a crown beam corbel 2 is provided at the top of the peripheral support pile 1, and a crown beam corbel 2 is provided below the crown beam corbel 2 near the top. There are steel purlins 4, basement corbels 3 are arranged on the top surface of basement base plate 5, and base plate corbels 3 are anchored into the base plate. A pair of H-shaped steel 6 of 500*30*11*28 is inserted in the peripheral support pile 1, and the length of the inserted steel in the pile body is equal; The other end is supported on the corbel 3 of the bottom plate; the other end is supported on the corbel 2 of the crown beam, and the other end is supported on the corbel 3 of the bottom plate.

As shown in FIG. 2 , the pit-facing surface of crown beam corbel 2 obliquely embeds steel plate 7 and steel mesh 8 , and H-shaped steel 9 is arranged perpendicular to said steel plate 7 .

As shown in Fig. 3, the steel plate 7 and steel mesh 8 are embedded obliquely on the back pit surface of the corbel 3 of the floor, including the vertical floor section perpendicular to the foundation floor of the basement and the oblique connecting section connected obliquely to the vertical floor section, and the vertical floor Both the section and the oblique connection section are perpendicular to the steel plate 7 and the H-shaped steel 9 is arranged.

According to the surrounding environment of the above foundation pit, the foundation pit support construction method using the foundation pit support device is as follows:

(1) Basin-type excavation in the central area, using the method of reserved soil to advance layer by layer;

(2) Basement foundation floor 5 and structural construction in the central area;

(3) After the foundation floor 5 and structure construction of the basement in the central area is completed, steel supports shall be built inwards on the surrounding support piles 1 and supported on the basement floor 5 of the basement in the central area;

(4) Excavating the earthwork in the area;

(5) Construction of basement foundation floor 5 and structure in this area;

(6) Remove the steel structure support after the concrete strength of the foundation floor 5 of the basement meets the requirements.

Before constructing the steel support in step 3, the steel support is spliced according to the net size and length of the foundation pit, and then the two lifting point hoisting method is used to hoist it in place as a whole. . The steel support is set as two double H-shaped steel 6 supports, and the horizontal distance between the two double H-shaped steel 6 supports is 9m. After the construction of the steel support is completed, the gap between the support and the waist beam, the crown beam corbel 2 and the floor corbel 3 must be filled with fine stone concrete to ensure that the end faces are fully stressed.

The construction of double H-shaped steel 6 supports in step 3 and the excavation of the earthwork in this area in step 4 are carried out alternately.

The construction of double H-shaped steel 6 supports in step 3 and the construction of basement foundation floor 5 and structure in step 5 are carried out alternately.

This specific embodiment is only an explanation of the utility model, and it is not a limitation of the utility model. After reading this description, those skilled in the art can make modifications to the embodiment without creative contribution according to needs, but as long as it is within the utility model All new claims are protected by patent law.

Claims (4)

1. A support device for a foundation pit, characterized in that: it includes a crown beam corbel (2) provided at the top of the peripheral support pile (1), and a crown beam corbel (2) arranged below the crown beam corbel (2) near the top Steel purlins (4) and bottom plate corbels (3) are set on the top surface of the basement foundation bottom plate (5), the bottom plate corbels (3) are anchored into the bottom plate, and the surrounding support piles (1) There are two double-piece H-shaped steels (6) inserted; one end of the double-piece H-shaped steel (6) is supported on the steel purlin (4), and the other end is supported on the floor corbel (3); the other double One end of the assembled H-shaped steel (6) is supported on the crown beam corbel (2), and the other end is supported on the bottom plate corbel (3). 2. A foundation pit support device according to claim 1, characterized in that: the pit facing surface of the crown beam corbel (2) is obliquely embedded in the steel plate (7) and steel mesh (8), An H-shaped steel (9) is arranged perpendicular to the steel plate (7). 3. A support device for a foundation pit according to claim 1 or 2, characterized in that: the back pit surface of the bottom corbel (3) is obliquely embedded in the steel plate (7) and steel mesh (8), An H-shaped steel (9) is arranged perpendicular to the steel plate (7). 4. A foundation pit supporting device according to claim 3, characterized in that: the back pit surface of the bottom corbel (3) includes a vertical bottom plate section perpendicular to the basement foundation bottom plate (5) and The vertical bottom plate section is an oblique connecting section connected obliquely, and the vertical bottom plate section and the oblique connecting section are both vertically provided with H-shaped steel (9).