Steel cofferdam anti-overturning structure

Abstract

The utility model relates to an anti-overturning structure of a steel cofferdam, the steel cofferdam comprises cofferdam piles, enclosing purlins are arranged on the inner walls of the cofferdam piles, anti-overturning piles are inserted into the inner sides and the outer sides of a plurality of cofferdam piles at certain intervals, and the insertion depth of the anti-overturning piles is larger than that of the cofferdam piles. The upper ends of the anti-overturning piles are higher than the top elevation of the cofferdam pile, the anti-overturning piles on the inner side are tightly attached to surrounding purlins on the inner wall of the cofferdam pile, a certain distance is formed between the anti-overturning piles on the outer side and the cofferdam pile, and the upper ends of the two opposite anti-overturning piles on the inner side and the outer side of the cofferdam pile are tensioned through a pull rod. The whole anti-overturning performance of the cofferdam can be guaranteed under the condition that the cofferdam piles cannot reach the designed buried depth.

Description

Technical Field

[0001] This utility model belongs to the field of bridge construction technology, and relates to a steel cofferdam for the construction of bridge deep foundation pit piers, specifically a steel cofferdam anti-overturning structure. Background Technology

[0002] During the excavation of bridge pier foundation pits, to prevent pit collapse, it is necessary to construct a cofferdam around the pit using Larssen sheet piles or interlocking steel pipe piles. To meet the overturning resistance requirements of the cofferdam, the penetration depth of the sheet piles (or steel pipe piles) should not be less than the design value. However, in actual cofferdam construction, rock strata are frequently encountered during the driving of sheet piles (or steel pipe piles), making driving difficult. Continuing to drive the piles under these circumstances not only results in a very slow driving progress but also a significant increase in construction costs; stopping driving the piles prevents the cofferdam from reaching the design depth, making it difficult to guarantee the overturning resistance of the cofferdam. Summary of the Invention

[0003] The purpose of this invention is to address the above-mentioned problems by providing a steel cofferdam anti-overturning structure that ensures the overall anti-overturning performance of the cofferdam even when the cofferdam piles are not deeply embedded in the soil, thus ensuring the safety of cofferdam construction.

[0004] The technical solution of this utility model is as follows:

[0005] An anti-overturning structure for a steel cofferdam, comprising multiple cofferdam piles connected in a ring by interlocking fasteners, with walers installed on the inner walls of the cofferdam piles, characterized in that: an anti-overturning pile is driven at regular intervals on the inner and outer sides of the multiple cofferdam piles, the driving depth of the anti-overturning pile is greater than the driving depth of the cofferdam pile, and the upper end of the anti-overturning pile is higher than the top elevation of the cofferdam pile, wherein the inner anti-overturning pile is in close contact with the walers on the inner wall of the cofferdam pile, and the outer anti-overturning pile is at a certain distance from the cofferdam pile, and a connecting beam is respectively installed on the outer side of the upper end of two opposite anti-overturning piles on the inner and outer sides of the cofferdam pile, and the two connecting beams are tightened at both ends by tie rods.

[0006] This invention involves installing anti-overturning piles inside and outside the cofferdam. The driving depth of the anti-overturning piles is greater than that of the cofferdam piles. The anti-overturning piles inside and outside the cofferdam are connected by tie rods to ensure the overall anti-overturning performance of the cofferdam even when the cofferdam piles cannot reach the designed driving depth. The number of anti-overturning piles is relatively small, significantly reducing construction costs compared to driving all cofferdam piles to the designed depth. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the elevation structure of this utility model;

[0008] Figure 2 This is a schematic diagram of the planar structure of this utility model. Detailed Implementation

[0009] like Figure 1 , Figure 2 As shown, the steel cofferdam includes multiple cofferdam piles 1 connected in a ring by interlocking fasteners. A waler 2 is provided on the inner wall of the cofferdam piles. An anti-overturning pile 3 is driven into the inner and outer sides of the multiple cofferdam piles at certain intervals. The driving depth of the anti-overturning pile 3 is greater than the driving depth of the cofferdam pile 1. The upper end of the anti-overturning pile 3 is higher than the top elevation of the cofferdam pile 1. The inner anti-overturning pile 3 is close to the waler 2 on the inner wall of the cofferdam pile, and the outer anti-overturning pile 3 is at a certain distance from the cofferdam pile 1. A connecting beam 4 is provided on the outer side of the upper end of two anti-overturning piles 3 that are opposite to each other on the inner and outer sides of the cofferdam pile. The two connecting beams 4 are tightened at both ends by tie rods 5.

[0010] This invention is applicable to situations where there is hard rock strata in the soil below the cofferdam. During the excavation of the foundation pit, after the upper layer is excavated, cofferdam piles 1 are first driven around the foundation pit to a certain depth. If hard rock strata are encountered, driving can be stopped, and the cofferdam piles can be connected to form a cofferdam. However, at this time, the cofferdam piles have poor overturning resistance because the soil penetration depth has not reached the design depth. To ensure construction safety, an anti-overturning pile 3 is driven at regular intervals on both the inner and outer sides of the cofferdam. The inner anti-overturning pile is driven close to the inner wall of the cofferdam pile waler 2, while the outer anti-overturning pile 3 is driven at a certain designed distance from the cofferdam pile 1. The anti-overturning pile 3 is driven to a depth greater than that of the cofferdam pile 1. Tie rods 5 are then installed between the inner and outer anti-overturning piles, and the foundation pit is then excavated to the design depth.

[0011] During the excavation of the foundation pit, the cofferdam pile 1 is squeezed by the outer soil and bears inward lateral pressure. The lateral pressure is transmitted to the inner anti-overturning pile 3, which in turn transmits the lateral pressure to the outer anti-overturning pile 3 through the tie rod 5. Since the outer anti-overturning pile 3 is located in the soil and rock strata outside the foundation pit and is blocked by the soil and rock strata, it has a strong anti-overturning capacity. Therefore, it ensures that the cofferdam pile will not tilt inward under the pressure of the outer soil layer, thus ensuring the safety of the cofferdam construction.

Claims

1. A steel cofferdam anti-overturning structure, the steel cofferdam comprising a plurality of cofferdam piles connected in a ring by interlocking fasteners, wherein walers are provided on the inner wall of the cofferdam piles, characterized in that: An anti-overturning pile is driven at regular intervals on the inner and outer sides of multiple cofferdam piles. The driving depth of the anti-overturning pile is greater than that of the cofferdam pile, and the upper end of the anti-overturning pile is higher than the top elevation of the cofferdam pile. The inner anti-overturning pile is close to the waler on the inner wall of the cofferdam pile, while the outer anti-overturning pile is at a certain distance from the cofferdam pile. A connecting beam is set on the outer side of the upper end of two opposite anti-overturning piles on the inner and outer sides of the cofferdam pile, and the two connecting beams are tightened by tie rods at both ends.

Images