PHC tubular pile pile-sinking device used for penetrating deep and dense sand (gravel) layer

Abstract

A PHC tubular pile pile-sinking device used for penetrating a deep and dense sand (gravel) layer comprises a PHC tubular pile (2), wherein both the upper part and the lower part of the PHC tubular pile (2) are provided with a pile cap (1) and a pile shoe (3) respectively in a connecting manner; a slurry inlet pipe (4), an air inlet pipe (6) and an air exhaust pipe (5) penetrate holes in the pile caps (1) to be mounted in inner holes of the PHC tubular pile (2). The PHC tubular pile pile-sinking device used for penetrating the deep and dense sand (gravel) layer has the advantages of: 1, guaranteeing successful overflow of returned slurry, 2, preventing excessive washing, 3, controlling placement positions of the slurry inlet pipe, the air inlet pipe and the air exhaust pipe quantitatively and guaranteeing penetration effect and quality, 4, changing traditional water washing into slurry washing, ensuring phenomena of hole collapse and quicksand not to happen easily in the sand (gravel) layer washing process as the slurry is made of traditional drilling slurry, cement of about 5%-10% and a retarding agent of 0.2%, avoiding excessive washing, and guaranteeing side friction of the PHC tubular pile and quality of guided holes, and 5, achieving rational design, simple structure, installation and operation convenience, reliable sealing performance and good penetration effects, and being economic and practical.

Description

technical field [0001] The invention relates to the technical field of foundation engineering, in particular to a novel PHC pipe pile sinking device for passing through deep and dense sand (gravel) layers. Background technique [0002] Compared with bored piles, PHC pipe piles have many advantages such as low cost, short construction period, environmental protection and easy guarantee of project quality, and are widely used in high-rise buildings and industrial plants. Especially in some industrial plants, it is used to place precision instruments and equipment. During the use of the plant, the requirements for foundation settlement are very high. Therefore, the depth of PHC pipe piles must be increased to pass through deep and dense sand (gravel) layers to achieve a more stable foundation. Bearing layers, and these deep and dense sand (gravel) layers generally have more than 50 hits in standard penetration. No matter whether it is static pressure or hammering pile sinking,...

AI Technical Summary

Problems solved by technology

Especially in some industrial plants, it is used to place precision instruments and equipment. During the use of the plant, the requirements for foundation settlement are very high. Therefore, the depth of PHC pipe piles must be increased to pass through deep and dense sand (gravel) layers to achieve a more stable foundation. Bearing layers, and these deep and dense sand (gravel) layers generally have more than 50 hits in standard penetration, and the pile sinking cannot be penetrated by static pressure or hammering.

[0003] The solution is generally to use water blasting and air lift to drive the pile, but the traditional pile sinking equipment encounters the following problems in the process of use: 1. There is no sealing and fixing device and exhaust pipe at the pile head, such as the new PHC pile and water The static pressure pile sinking method with air-lifting (patent number: 200410061106.9), without sealing and fixing devices and exhaust pipes, during the construction process, the pressure of water injection and air injection is not easy to guarantee and control, and sometimes the pressure is too high, resulting in excessive erosion, construction The quality cannot be guaranteed, and the returned slurry at the pile head splashes everywhere, burying potential safety hazards; the pistons of the return hole and outlet hole of the pile shoe may not be opened normally if the pressure is too small, resulting in failure to flush, or large pieces of gravel cannot be returned together with the slurry; For example, a flushing device for reinforced concrete prefabricated pile sinking (patent number: 02278050.5), which is composed of a water inlet pipe, an air inlet pipe, a cavity, a casing and an outlet pipe, and has no exhaust pipe. Although the patent mentions The upper sealing device has not been described in detail, and it is not clear whether it can play a sealing role; 2. During the flushing process, the sand (gravel) layer is prone to collapse holes and quicksand, and even if adjacent holes are also sunk by this method When piles are piled, the sand (gravel) layer will be hollowed out and connected, which will cause problems such as unstable bearing capacity after construction and difficult control of construction quality.

Images