Rotary excavating hole-forming construction method for building pile foundation

Abstract

The invention discloses a rotary excavating hole-forming construction method for a building pile foundation. A pile hole is excavated, and a pile shell with steel bars and a steel bar cage are manufactured. An accumulated soil fall stopping device is arranged on an outer side surface of the pipe shell. The pipe shell with the accumulated soil fall stopping device and the steel bar cage at the bottom end of the pile shell are placed in the pile hole. Dregs at the bottom of the hole and on the wall of the hole are cleaned. Concrete is poured in the pile shell with the steel bars, the building pile foundation is obtained, and a gap between the outer side of the pile shell with the steel bars and a pile hole wall is backfilled. According to the rotary excavating hole-forming construction method for the building pile foundation, the pile shell and the accumulated soil fall stopping device are adopted, and a loose soil layer is effectively prevented from dropping to the bottom in the pile hole and a formed pile, so that quality of the formed pile is improved. High safe assurance is provided to a worker to clean the dregs at the bottom. The dregs on the bottom and the side wall of the pile hole are eliminated through a pouring and discharging device, the pouring and discharging device is convenient to operate, almost all dregs can be cleaned, and cleaning effect is much better than the engineering standard. The pile hole is excavated through rotary excavating mechanical equipment, the efficiency of construction is high, a large amount of labor is saved, and the construction is safe.

Description

technical field [0001] The invention relates to a construction method for building pile foundations, in particular to a construction method for rotary digging and forming holes for building pile foundations. Background technique [0002] The pile hole of the pile foundation of the building is traditionally excavated by hand, and the diameter is enlarged at the bottom of the artificially dug hole pile, which is called the artificially dug hole expanded bottom pile. Due to its reliable mechanical performance, this type of pile does not require large machinery and equipment The construction operation process is simple, and the rock and soil conditions at the bottom of the pile can be directly checked. The single pile has a high bearing capacity and no environmental pollution, so it is widely used in various places. However, this type of pile hole has the following disadvantages: the labor intensity in digging the hole is relatively high, the construction speed of the single pil...

AI Technical Summary

Problems solved by technology

However, this type of pile hole has the following disadvantages: the labor intensity in digging the hole is relatively high, the construction speed of the single pile is slow, especially the safety is poor, and dangers such as landslides are prone to occur. When scattered into the hole, a large amount of toxic gas will be deposited at the bottom of the pile hole, which will bring safety hazards to construction safety

However, the existing rotary excavation pile technology cannot adapt to the construction of a large number of backfill soil layers such as Chongqing and other hills and mountains, that is, the upper part of the construction ground is a loose soil layer (backfill soil layer), and the lower part is a rock layer: the main reason It is the following two points: 1. When the upper layer of the pile hole has a loose soil layer such as backfill soil, during the process of lowering the reinforcement cage and concrete pouring in the rotary excavation pile hole, the loose soil layer or concrete pouring process will continue to be rubbed with the lowering of the reinforcement cage. Part of the soil in the loose soil layer will fall into the bottom of the pile hole or the concrete and exist in the solidified concrete pile body, reducing the quality of the concrete pile body, reducing the bearing capacity of the pile foundation, or even significantly reducing it. Larger or serious safety hazards; second, the sediment at the bottom of the rotary excavation pile (the loose soil layer or the stone powder formed by the friction between the rotary excavation pile head and the rock) cannot be removed, so that it cannot meet the engineering standard (the thickness of the soft layer at the bottom of the pile hole is less than 5cm)

Third, when digging holes, if there is a deviation in the pile hole of the rotary excavation, the poured concrete pile will also have a deviation, which cannot be corrected, resulting in the position of the concrete pile not meeting the design requirements, and there is also a large potential safety hazard

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