Construction technique for preventing hole collapse of bored cast-in-place pile

Abstract

The invention discloses a construction technique for preventing hole collapse of a bored cast-in-place pile. The construction technique for preventing the hole collapse of the bored cast-in-place pile is characterized in that the construction technique comprises the steps that (1) a pile casing is buried in a soil layer according to a pile position control line, and a drilling machine is started to drill after a mud circulating system and the drilling machine are well prepared; (2) normal drilling is carried out in the soil layer, and drilling is stopped and a drill bit is lifted when the drill bit is located in a soft soil layer and it is difficult to continue to drill downwards for the drilling machine; (3) the drilling machine is moved after drilling is stopped, concrete is poured into a drill hole rapidly till the surface of the concrete is higher than the set upper surface of the soft soil layer, and a rigid protective wall is formed after the concrete is solidified; (4) the drill bit is replaced with a rock drill bit; (5) the rock drill bit is replaced with the original excavating drill bit after the rock drill bit penetrates through the concrete located in the soft soil layer to enable rapid drilling to be carried out continuously till a hole is formed. The construction technique for preventing the hole collapse of the bored cast-in-place pile has the advantages that the problem that the lateral supporting force, in the soft soil layer, of a protective wall which is formed only by slurry is insufficient is solved, the hole collapse of soil layers with strong flow plasticity is prevented, and drilling success rate is improved.

Description

technical field [0001] The invention relates to a concrete pouring technique, in particular to a construction technique for preventing bored piles from collapsing when low-grade concrete is poured. Belongs to the field of civil engineering. Background technique [0002] At present, when the bored pile is drilled into the hole, the mud wall protection method is generally adopted to prevent the hole wall from collapsing. [0003] The main process of traditional bored piles includes: 1. Measurement and setting out; 2. Hole forming; 3. Reinforcement cage hanging; Steps: ⑴mud preparation; ⑵casing burial; ⑶drilling rig in place; ⑷drilling; [0004] In the drilling, the mud is circulated in the mud pool, slow slurry pool, and pile holes to play the role of wall protection, sand carrying, and cooling of the drill bit. When drilling into the mud layer, it is mainly to control the drilling speed. That is: when the collapse is small, you can sweep the hole first, and then continue d...

AI Technical Summary

Problems solved by technology

However, when the above-mentioned construction procedures run into weak soil layers such as strong flow plastic and soft plastic silt layers, because the retaining wall has insufficient lateral support in the weak soil layer, the hole wall collapses easily;

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