Pile foundation hole forming construction process under large-particle-size cobble sandy soil and severe water seepage geological condition

Abstract

The invention discloses a pile foundation hole forming construction process under the large-particle-size cobble sandy soil and severe water seepage geological condition. Holes are formed through a follow-up process that rotary drilling rig drilling is matched with a steel casing. The pile foundation hole forming construction process comprises the specific construction steps that 1, site formation is conducted, specifically, site formation of a pioneer road and site formation within a construction area range are conducted; 2, pile position lofting is conducted, specifically, on the basis of technical disclosure data, surveying and setting out are conducted through a total station, the specific position of a pile is determined, and a marker is made in the center of the pile in the mode of coating a short steel bar with paint; and 3, outer-side steel casing inserting and beating are conducted, specifically, an outer-side steel casing is inserted and beat to the position 4-6 m under the river bed ground with a crawler crane being matched with a hydraulic vibration hammer, the wall thickness of the outer-side steel casing is not less than 10 mm, and the diameter of the outer-side steel casing is 40 cm larger than that of the actual drilled pile. According to the pile foundation hole forming construction process under the large-particle-size cobble sandy soil and severe water seepage geological condition, the problem that drilling is difficult due to the fact that a rotary drilling rig encounters large-particle-size cobbles during construction is solved, the amount of drill slag after the holes are formed is decreased, the problem that the holes are not cleaned thoroughly is solved, accordingly, the drilling time is shortened, and the formed hole quality is improved.

Description

technical field [0001] The invention relates to a construction technique for pile foundation hole forming under the geological conditions of large particle size pebble sand and serious water seepage, mainly used in the hole forming construction of pile foundation rotary drilling rig, and overcomes the problem of large particle size in the construction of rotary drilling rig. Difficult drilling of diameter pebbles, avoiding the problem of hole collapse during the drilling process under the condition of severe water seepage and difficult mud protection, reducing the amount of drilling slag after hole formation, avoiding the problem of incomplete hole cleaning, thereby reducing drilling time and improving hole quality . Background technique [0002] Drilling a hole with a rotary drilling rig is a common hole-forming process for pile foundations, and is widely used in the construction of pile foundations for railways, highways, bridges and large buildings. [0003] In the hole-...

AI Technical Summary

Problems solved by technology

However, under the geological conditions of sandy soil with large particle size pebbles and severe water seepage, the large particle size pebbles will wear the drill bit greatly, which will affect the drilling progress; under the influence of severe penetration of water flow, the mud will not be able to play the role of protecting the wall, which will lead to collapse. holes, increasing the quality and safety hazards in the hole making process