Anti-skid drill cast-in-place pile foundation in high-sensitivity soft soil area and construction method thereof

Abstract

The invention discloses an anti-skid drill cast-in-place pile foundation in a high-sensitivity soft soil area and a construction method thereof. The anti-skid drill cast-in-place pile foundation comprises novel steel protecting cylinders, a steel protecting cylinder installing device and a drill cast-in-place pile main body. The drill cast-in-place pile main body comprises common steel protectingcylinders, a steel reinforcement cage and concrete. All the novel steel protecting cylinders and all the common steel protecting cylinders are sequentially connected in a sealed manner from bottom totop. The steel protecting cylinder installing device comprises a suction barrel and a magnetic installing ejection cap. According to the anti-skid drill cast-in-place pile foundation, the novel steelprotecting cylinders with automatic hole pressure adjusting systems are adopted, and thus during the operation stage of the anti-skid drill cast-in-place pile foundation in the high-sensitivity soft soil area, hole water pressure in a periphery soil body of the pile foundation can be adjusted automatically. The suction barrel technology is adopted for installing the steel protecting cylinders, itis ensured that in the construction process, the soil body on the periphery of an anti-skid drill cast-in-place pile is reduced as much as possible, and the liquefaction risk of the soil body on the periphery of the pile foundation during the construction period is effectively reduced. The construction method is safe, reliable, convenient and rapid, and has a wide project application prospect.

Description

technical field [0001] The invention relates to the technical field of bored pile foundations, in particular to an anti-skid bored pile foundation in a highly sensitive soft soil area and a construction method thereof. Background technique [0002] With the rapid advancement of my country's urbanization process, a large number of cross-river / river bridges, sea-crossing bridges, river / river roads, coastal roads, and a series of water (river / river or sea) viewing platforms and other engineering projects have emerged. Pile-like foundations (especially underwater bored pile foundations) have played an important role in the smooth construction and normal operation of the above-mentioned projects. [0003] High-sensitivity soft soils with large porosity, low shear strength, and easily disturbed are widely distributed on river alluvial plains, river estuaries, and continental shelves, and underwater high-sensitivity soft soil slopes are formed in areas extending from land to rivers ...

AI Technical Summary

Problems solved by technology

In fact, under the action of construction load, wave load, vibration of the structure itself and its upper working load, storm surge, earthquake and other natural disasters, not only the microstructure of the highly sensitive soft soil will be destroyed and its strength softened after being disturbed, but also The excess static pore water pressure will gradually form in the soft soil layer around the foundation of the underwater anti-sliding bored pile. According to the principle of effective stress, as the pore water pressure in the soft soil layer increases, the effective stress will decrease, resulting in The shear strength of the soil also decreases, which may cause landslides on highly sensitive soft soil slopes underwater, and then induce slippage or fracture of the underwater anti-slide bored pile foundation, and even cause underwater anti-slide The overall overturning damage of the bored pile foundation and its superstructure may cause casualties and huge property losses

[0004] At present, the common installation of the steel casing of the underwater bored pile is to penetrate into the underwater soft soil by means of shock vibration or hammering. This kind of traditional installation method of the steel casing will seriously disturb the soft soil around the steel casing. , to soften the strength of the soil; on the other hand, it will also form an excess static pore water pressure in the soft soil around the steel casing. If the accumulated excess static pore water pressure is not dissipated in time, it will make the highly sensitive soft soil area anti-skid Liquefaction damage occurs in the soil around the bored pile foundation, which adversely affects the stability of the underwater anti-slide bored pile foundation during construction and operation

In a coastal landscape platform construction project, the steel casing installed by the traditional shock vibration method was broken, the underwater bored pile could not be piled, and even the highly sensitive soft soil slope around the steel casing landslides in a large area, resulting in the entire The Accident of the Construction Platform Collapse of Underwater Grouting Pile

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