Pile foundation construction method in high fill foundation

Abstract

The invention discloses a pile foundation construction method in a high fill foundation, which can reduce the hole collapse phenomenon, improve the installation efficiency of a reinforcement cage, prevent the reinforcement cage from floating upwards and improve the construction efficiency while enabling the concrete quality of a pile body of the pile foundation to meet the design requirement. The method comprises the steps of field leveling, pile position lofting, pile casing manufacturing, pile casing burying, drilling machine in-place, slurry circulation, drilling, hole cleaning, steel reinforcement framework placing, guide pipe installing, concrete pouring, pile casing pulling out and pile head breaking.

Description

technical field [0001] The invention relates to the technical field of engineering construction, in particular to a pile foundation construction method in a high fill foundation. Background technique [0002] According to the "National Standards of the People's Republic of China High Fill Foundation Technical Specifications" (GB 51254-2017), high fill foundation refers to, in order to solve the land for engineering construction, it is filled in layers manually and adopts dynamic compaction, vibration rolling, impact Sites or foundations formed by compaction or other technical treatment measures with a filling thickness greater than 20m. [0003] The pile foundation construction process is complex, the construction period is long, and multiple key construction steps are prone to conflicts, resulting in the failure of the final pile foundation to meet the design requirements. For example, during the drilling process, if there are many sand-bearing layers, the drilling liquid ...

AI Technical Summary

Problems solved by technology

[0003] The pile foundation construction process is complex, the construction period is long, and multiple key construction steps are prone to conflicts, resulting in the final pile foundation failing to meet the design requirements

For example, during the drilling process, if there are many sand-bearing layers, the drilling liquid level changes rapidly, resulting in an imbalance of formation pressure and accidents such as hole collapse.

When carrying out pile foundation construction on high fill foundation, in order to ensure that the pile foundation is firm, the drilling depth is usually larger. Therefore, the length of the pile foundation reinforcement cage is longer. On the one hand, it is difficult to connect multi-section reinforcement cages while maintaining the structural strength. Realize quick docking

Moreover, due to the long length of the reinforcement cage, it is easy to cause impact deformation of the reinforcement cage during hoisting into the hole

In the process of underwater concrete pouring, it often occurs that the slurry surface sinks too much, which leads to the imbalance of the static column pressure in the hole and the hole phenomenon.

In addition, because the poured concrete was pulled out from the conduit, the pressure from bottom to top was high, which lifted the steel cage to float up, resulting in the failure of the final foundation pile to meet the design requirements

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