Drilling grout pile end follow-up grouting construction method

Abstract

The invention relates to a post-grouting construction method for ends of bored cast-in-place piles, in specific to steps as follows: (1) Grouting depth determination and grouting device maunfaucturing; (2) Grout fluid configuration; (3) Grouting. Kernel devices for the invented post-grouting construction method, such as grouting pipelines and etc, are characterized in simple structure and convenient execution; the method can take duplicated reinforcement effects for pile-earth boundary around pile bodies and pile ends in both physical reinforcement and chemical reinforcement; the solidified sludge can take the effect of diameter expansion for the pile ends, so as to change properties of bearing stratums; meanwhile, upwelled grout fluid can solidify the sludge skin around piles, in order to take effects in increasing pile side friction resistance. Since the invented method can well resolves defects in construction of boundaries between cast-in-place piles and earth; unit pile bearing capacity of cast-in-place piles adopting the pile end post-grouting construction method, in soft earth area like Shanghai, is fundamentally improved by 20 percent to 30 percent higher than that of routine cast-in-place piles, and several examples can even reach 70 percent extremely.

Description

technical field [0001] The invention relates to a grouting method in building construction, in particular to a post-grouting method for pile ends of bored piles. Background technique [0002] Since the 1980s, bored piles have been widely used in high-rise buildings and municipal construction because of their advantages such as simple construction, no soil extrusion, no vibration, and low noise. However, due to the formation of overly thick pile bottom sediment and pile side mud skin in the drilling process of the mud retaining wall, the hole wall is easily affected by disturbance and soaking in water, etc., resulting in the failure of pile quality and single pile bearing capacity. Discrete phenomena. Especially in the typical soft soil area of ​​Shanghai, if the bored pile passes through a thicker sand layer, and the diameter is larger and the pile length is longer, the quality of the pile is more difficult to guarantee. [0003] Post-grouting technology at pile tip is a n...

AI Technical Summary

Problems solved by technology

In the initial stage of application in Shanghai, the post-grouting technology was often unable to form a unified and effective construction method due to differences in grouting equipment, grout materials, and construction techniques

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