A connection structure for the first precast concrete support system of a foundation pit

Abstract

The present invention relates to a connection structure for a first-line precast concrete support system for a foundation pit, wherein the crown beam is a precast crown beam, the first-line concrete support is a precast first-line concrete support, the precast crown beam is connected to the retaining pile, an I-shaped groove with a step is provided on the precast crown beam, the end of the precast first-line concrete support is an I-shaped shape that matches the I-shaped groove, and the end of the precast first-line concrete support is supported in the I-shaped groove and anchored to the precast crown beam. The advantages of the present invention are: the connection of the two components is achieved by using a pre-embedded steel plate on the top of the retaining pile and a precast crown beam pre-embedded steel plate and welding them through a crisscross steel plate; anchor bolts are used to achieve the connection between the precast crown beam and the precast first-line concrete support; the first-line concrete support system for the foundation pit can be quickly installed and dismantled, and the invention has the characteristics of few construction steps, simple process, low cost, and reusability.

Description

Technical Field

[0001] The invention relates to the technical field of foundation pit construction, in particular to a connection structure of a first precast concrete support system of a foundation pit. Background Art

[0002] Prefabrication is a current development trend in the transportation construction industry. It is not only fast, reliable, and highly standardized, but also intelligent and environmentally friendly. The retaining system of the foundation pit is a temporary structure, generally designed to have a service life of no more than two years. During the design and construction of the foundation pit, the retaining pile cap beam and the first concrete support are generally cast-in-place concrete structures. After the main structure of the foundation pit is completed, the cap beam and the first concrete support need to be removed to meet the requirements for laying pipelines above the structure. The main disadvantages of the traditional cast-in-place first concrete support system are as follows:

[0003] 1) The cast-in-place construction process is complicated, the construction period is long, and the construction quality cannot be guaranteed;

[0004] 2) Cast-in-place construction consumes a lot of manpower and material resources, cannot be reused, and is costly;

[0005] 3) The demolition of temporary structures not only wastes materials but also generates a large amount of construction waste. The demolition process is noisy and dusty, and the work efficiency is extremely poor.

[0006] 4) The demolition of temporary structures requires large equipment. If the equipment and garbage are not stacked properly during the demolition process, the main structure and waterproofing will be easily damaged. Summary of the Invention

[0007] The purpose of the present invention is to provide a connection structure for the first precast concrete support system of a foundation pit based on the above-mentioned deficiencies of the prior art. Through the design of the precast assembly structure, the foundation pit retaining piles, precast crown beams and the first precast concrete support can be quickly assembled, while ensuring the reliable connection between the retaining piles, precast crown beams and the first precast concrete support, thereby ensuring the structural strength and stability of the foundation pit retaining system.

[0008] The purpose of the present invention is achieved by the following technical solutions:

[0009] A connection structure of the first precast concrete support system of a foundation pit, comprising retaining piles, a crown beam and a first concrete support, wherein the crown beam is arranged above the retaining piles, and the first concrete support is connected to the crown beam, and is characterized in that: the crown beam is a precast crown beam, the first concrete support is a precast first concrete support, the precast crown beam is connected to the retaining piles, an I-shaped groove with a step is provided on the precast crown beam, the end of the precast first concrete support is an I-shaped groove matching the I-shaped groove, the end of the precast first concrete support is supported in the I-shaped groove and anchored to the precast crown beam.

[0010] The top of the retaining pile is pre-buried with a retaining pile steel plate and connecting steel bars, the connecting steel bars are implanted in the retaining pile, the retaining pile steel plate is connected to the top of the connecting steel bars, and the retaining pile steel plate is connected to the prefabricated crown beam.

[0011] The prefabricated crown beam is preset with a cavity at the position corresponding to the guardrail pile, and a crown beam connecting steel plate is pre-buried in the cavity. Connecting anchor bars are arranged on the periphery of the crown beam connecting steel plate, and the connecting anchor bars are implanted in the prefabricated crown beam. The crown beam connecting steel plate is connected and fixed to the guardrail pile steel plate.

[0012] A cross-shaped steel plate is provided on the inner side of the crown beam connecting steel plate, and the cross-shaped steel plate is connected and fixed to the retaining pile steel plate.

[0013] The crown beam connecting steel plate is annular, and the connecting anchor bars are evenly arranged in a scattered manner on the periphery of the crown beam connecting steel plate along the annular direction of the crown beam connecting steel plate.

[0014] The prefabricated crown beam is provided with a crown beam steel sleeve, which corresponds to the end position of the prefabricated first concrete support. The end of the prefabricated first concrete support is anchored to the crown beam steel sleeve through a connecting anchor bolt.

[0015] The advantages of the present invention are:

[0016] 1) Pre-embedded steel plates on the top of the retaining piles and pre-embedded steel plates on the prefabricated crown beams are used to connect the two components through cross-shaped steel plate welding. Anchor bolts are used to connect the prefabricated crown beams to the prefabricated first concrete support. This allows for rapid installation and removal of the first concrete support system in the foundation pit, with the advantages of fewer construction steps, simple process, low cost, and reusability.

[0017] 2) The retaining piles are connected to the prefabricated crown beams through a cross-shaped steel plate, which can withstand the shear force transmitted from the retaining piles and ensure that the retaining piles form an integral load-bearing structure;

[0018] 3) The first prefabricated support and the prefabricated crown beam are connected by anchor bolts, which can withstand both pressure and tension, meeting the requirements of stability, bearing capacity and deformation resistance of foundation pit excavation;

[0019] 4) It can ensure that the foundation pit retaining structure is stressed, the crown beam and the first concrete support are processed in the prefabrication yard to significantly improve the project quality. The first support system is prefabricated and installed to improve work efficiency. At the same time, the proposed construction method of connecting the retaining piles with the prefabricated crown beam, and the prefabricated support with the prefabricated crown beam can speed up the construction speed. It is suitable for use in various foundation pit projects, has a wide range of applications, and is suitable for promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a plan view of the present invention;

[0021] Figure 2 This is a structural diagram of the connection between the prefabricated I-shaped concrete support and the prefabricated crown beam in the present invention;

[0022] Figure 3 This is a structural diagram of the connection between the retaining piles and the prefabricated crown beam in the present invention. DETAILED DESCRIPTION

[0023] The features of the present invention and other related features are further described in detail below through embodiments in conjunction with the accompanying drawings to facilitate understanding by those skilled in the art:

[0024] like Figure 1-3 As shown in the figure, marks 1-11 respectively represent: precast crown beam 1, precast concrete first support 2, crown beam steel sleeve 3, connecting anchor bolt 4, support steel plate 5, crown beam connecting anchor bar 6, crown beam connecting steel plate 7, cross steel plate 8, guardrail pile 9, guardrail pile steel plate 10, and embedded connecting steel bar 11.

[0025] Example: Figures 1 to 3 As shown, the connection structure of the first precast concrete support system for the foundation pit in this embodiment is used to connect the precast crown beam 1, the precast concrete first support 2, and the retaining piles 9 to form a complete foundation pit retaining system. The retaining piles 9 are arranged at the pit wall, the precast crown beam 1 is installed at the top of several retaining piles 9 to connect them to form a complete structure, and the precast concrete first support 2 is supported between the precast crown beams 1 on opposite sides.

[0026] like Figure 1 As shown, the connection structure of the first precast concrete support system of the foundation pit in this embodiment includes the connection structure between the precast crown beam 1 and the retaining pile 9, and the connection structure between the precast crown beam 1 and the precast concrete first support 2. By designing the two, the support system can be quickly installed and dismantled.

[0027] Specifically, combined Figure 1 and Figure 3 As shown, pre-embedded connecting steel bars 11 are evenly arranged on the top of the retaining pile 9, and each pre-embedded connecting steel bar 11 is implanted inside the pile body of the retaining pile 9. A retaining pile steel plate 10 is welded to the top of each pre-embedded connecting steel bar 11. During the prefabrication process, the prefabricated crown beam 1 is pre-embedded with a ring-shaped crown beam connecting steel plate 7, and the crown beam connecting steel plate 7 is evenly scattered in the annular direction with crown beam connecting anchor bars 6, and the crown beam connecting anchor bars 6 are implanted during the prefabrication process of the prefabricated crown beam 1. The crown beam connecting steel plate 7 of the prefabricated crown beam 1 and the retaining pile steel plate 10 of the retaining pile 9 are fixedly connected by welding a cross steel plate 8, so that the prefabricated crown beam 1 and the retaining pile 9 are fixedly connected to form an integral structure. At this time, the prefabricated crown beam 1 can withstand the shear force transmitted from the retaining pile 9 through the cross steel plate 8, ensuring that a plurality of retaining piles 9 form an integral force-bearing structure.

[0028] Combine Figure 1 and Figure 2 As shown, the precast crown beam 1 is provided with an I-shaped groove with steps, and the end of the precast concrete first support 2 is an I-shaped shape that matches the I-shaped groove; the end of the precast concrete first support 2 can be supported at the step position of the I-shaped groove. At the same time, a crown beam steel sleeve 3 is provided at the I-shaped groove of the precast crown beam 1. When the precast concrete first support 2 is supported in the I-shaped groove, the connection anchor 4 can be passed through the end of the precast concrete first support 2 and anchored to the crown beam steel sleeve 3 to achieve a fixed connection between the precast concrete first support 2 and the precast crown beam 1. At this time, the precast concrete first support 2 connected to the precast crown beam 1 can withstand both pressure and tension, meeting the requirements of stability, bearing capacity and deformation resistance of foundation pit excavation.

[0029] In this embodiment, the I-shaped end of the precast concrete first support 2 extends into the I-shaped groove of the precast crown beam 1, so that the shear force on the precast concrete first support 2 can be borne by the step of the I-shaped groove, while the axial force can be borne by the connecting anchor bolt 4, thereby improving the supporting effect of the precast concrete first support 2. At the same time, through the connection structure between each retaining pile 9 and the precast crown beam 1, the surrounding soil pressure on the precast crown beam 1 and the retaining piles is more effectively and comprehensively transmitted to the precast concrete first support 2, thereby improving the retaining effect and stability of the foundation pit retaining system.

[0030] During construction, this embodiment includes the following steps:

[0031] 1) Prefabricated crown beam 1 and prefabricated concrete first support 2 are manufactured in the factory.

[0032] 2) Transport the prefabricated crown beam 1 and the prefabricated concrete first support 2 to the construction site; hoist the prefabricated crown beam 1 in sections and place them above each retaining pile 9; weld the cross-shaped steel plate 8 to the retaining pile steel plate 10 and the crown beam connecting steel plate 7 to achieve a reliable connection between each retaining pile 9 and the prefabricated crown beam 1.

[0033] 3) After the prefabricated crown beam 1 is installed in place, start hoisting the prefabricated concrete first support 2, support the I-shaped end of the prefabricated concrete first support 2 on the step of the I-shaped groove of the prefabricated crown beam 1, and then anchor it to the crown beam steel sleeve 3 by passing through the connecting anchor bolt 4 of the I-shaped end of the prefabricated concrete first support 2, so as to achieve a reliable connection between the prefabricated crown beam 1 and the I-shaped prefabricated concrete first support 2.

[0034] In the specific implementation of this embodiment: Figure 1 or Figure 2As shown, a support steel plate 5 is provided on the outside of the I-shaped end of the connecting anchor 4 at the precast concrete first support 2. The support steel plate 5 is used to improve the anchoring performance of the connecting anchor 4 and to provide a certain protection effect on the precast concrete first support 2.

[0035] Although the above embodiments have described in detail the concepts and embodiments of the present invention with reference to the accompanying drawings, ordinary technicians in this field can recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, so they are not described in detail here.

Claims

1. A connection structure for the first precast concrete support system of a foundation pit, comprising retaining piles, a crown beam, and a first concrete support, wherein the crown beam is arranged above the retaining piles, and the first concrete support is connected to the crown beam, characterized in that: The crown beam is a prefabricated crown beam, the first concrete support is a prefabricated first concrete support, the prefabricated crown beam is connected to the retaining pile, an I-shaped groove with a step is provided on the prefabricated crown beam, the end of the prefabricated first concrete support is an I-shaped groove that matches the I-shaped groove, and the end of the prefabricated first concrete support is supported in the I-shaped groove and anchored to the prefabricated crown beam; A retaining pile steel plate and connecting steel bars are pre-buried on the top of the retaining pile, the connecting steel bars are embedded in the retaining pile, the retaining pile steel plate is connected to the top of the connecting steel bars, and the retaining pile steel plate is connected to the prefabricated crown beam; The prefabricated crown beam is provided with a cavity at a position corresponding to the retaining pile, a crown beam connecting steel plate is embedded in the cavity, connecting anchor bars are provided on the periphery of the crown beam connecting steel plate, the connecting anchor bars are embedded in the prefabricated crown beam, and the crown beam connecting steel plate is connected and fixed to the retaining pile steel plate; A cross-shaped steel plate is provided on the inner side of the crown beam connecting steel plate, and the cross-shaped steel plate is connected and fixed to the retaining pile steel plate; The crown beam connecting steel plate is annular, and the connecting anchor bars are evenly arranged in a scattered manner on the periphery of the crown beam connecting steel plate along the annular direction of the crown beam connecting steel plate; The cross-shaped steel plate is welded to the retaining pile steel plate and the crown beam connecting steel plate respectively to achieve a reliable connection between each retaining pile and the prefabricated crown beam.

2. The connection structure of the first precast concrete support system of a foundation pit according to claim 1, characterized in that: The prefabricated crown beam is provided with a crown beam steel sleeve, which corresponds to the end position of the prefabricated first concrete support. The end of the prefabricated first concrete support is anchored to the crown beam steel sleeve through a connecting anchor bolt.

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