Hole forming method for ultra-deep large-diameter bored pile

Abstract

The invention relates to a hole forming method for an ultra-deep large-diameter bored pile. The hole forming method is characterized by comprising the following steps: 1, a pile casing guide frame ismanufactured; 2, the pile casing guide frame is positioned; 3, a steel pipe casing is inserted and driven; 4, a tapping drilling machine is in place; 5, a slurry circulating system is arranged, and slurry is prepared; 6, a hole is opened; 7, primary broaching is conducted; 8, secondary broaching is conducted;9, third-stage broaching is conducted; and 10, hole-forming detection is conducted. Hole forming of the large-diameter ultra-deep bored pile can be completed under the condition without a special drilling machine for the ultra-deep large-diameter bored pile, the hole forming precision is high, the hole forming period is short, safety can be guaranteed, and the cost is reduced.

Description

technical field [0001] The invention relates to bridge engineering, in particular to a method for forming holes for ultra-deep and large-diameter bored piles. Background technique [0002] The design and construction level of large-diameter bored piles for bridges in my country are in the forefront of the world. For large bridge projects, bored piles are generally used as the preferred foundation form. At present, the largest recorded diameter of bored piles in China is Wuhan Tianxingzhou Bridge. The pile length is 76m, and the diameter has reached 3.4m. It is a rock-socketed pile. The largest pile length of a single pile is the North Channel Bridge of the Hangzhou Bay Cross-sea Bridge. The pile length has exceeded 125m, and the pile diameter is 2.8m. It is a friction pile. At present, only the KTY-3000 gas lift reverse circulation drilling rig of China Railway Bridge Bureau can drill in place at one time in China, and the conventional single drilling equipment and constru...

AI Technical Summary

Problems solved by technology

[0003] CN 104047543A discloses "a construction method for forming holes with large-diameter bored piles in high-strength rock formations". By adopting multiple coring methods and using drill bits of different diameters, multiple cores are taken from high-strength rock formations , and finally completed the drilling of the bored pile embedded in the rock, which effectively solved the problems of low construction efficiency and large vibration interference in the existing technology, improved the quality of the hole, reduced the construction risk, etc., and has the advantages of fast construction speed and environmental protection The characteristics of small impact and high economic benefit

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