Construction method of air shaft cast-in-situ bored pile

Abstract

The invention discloses a construction method of an air shaft cast-in-situ bored pile. The construction method comprises the following steps of (1) setting out and positioning, (2) pile casing burying, (3) drilling machine in-place, (4) drilling hole forming, (5) primary hole cleaning, (6) hole forming detection, (7) reinforcement cage placement, (8) guide pipe lowering, (9) secondary hole cleaning and (10) concrete pouring and pile casing pulling. The water level in the hole is higher than the water level of underground water in the drilling process; after the drilling machine drills to the designed hole depth, a drill bit is lifted 300-500 mm away from the bottom of the hole, slow rotation is performed, primary hole cleaning is performed, and the time is 2-3.5 h; when pebbles or gravelswith the diameter smaller than 10 cm exist at the bottom of the hole, a reverse circulation method is adopted for hole cleaning; and when the size of pebbles or gravels existing at the bottom of the hole is larger than 10 cm, a pumping reverse circulation method is adopted for secondary cleaning in the hole. According to the construction method, the drill hole is effectively prevented from collapsing, and drilling tool clamping and burying and main winch steel rope breakage are avoided.

Description

technical field [0001] The invention belongs to the technical field of construction, and in particular relates to a construction method of bored piles for wind shafts. Background technique [0002] Bored cast-in-place pile is a technology commonly used in foundation construction. Cast-in-situ pile is a kind of pile made by pouring concrete or reinforced concrete after forming a hole in place. Commonly used methods include rotary drilling bored pile and immersed tube cast-in-place pile. and explosive expansion of cast-in-place piles. [0003] However, due to the different engineering geological structures in the specific construction, the construction platform is often unstable, the drilling hole collapses, the drilling tool is stuck, and the main hoisting steel rope breaks, etc., which seriously affect the construction progress and construction quality. security cannot be effectively guaranteed. Contents of the invention [0004] In view of this, the object of the presen...

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Problems solved by technology

[0003] However, due to the different engineering geological structures in the specific construction, the construction platform is often unstable, the drilling hole collapses, the drilling tool is stuck, and the main hoisting steel rope breaks, etc., which seriously affect the construction progress and construction quality. The safety of the