静压桩挤土效应及防治措施研究

静压桩在沉桩过程中产生的挤土效应十分明显。沉桩时产生巨大的挤压作用使桩区及附近相当范围内的土体产生向上隆起和水平位移,桩体上抬、偏位、折断时有发生。本文介绍了静压桩的贯入机理以及沉桩挤土效应研究的发展及现状,分析了土体位移机理,并就挤土效应所涉及的几个力学问题进行了较详细地分析,总结了现有的减少沉桩挤土效应的设计和施工两方面的工程措施。结合工程实例,说明采取综合预防措施的有效性,并提出一些合理化建议。

Research on Soil Squeezing Effect of Static Pressure Pile and Protective Measures

As a type of soil compaction piling,static piling often causes negative effects.During piles driving,soil horizontal displacement and excess pore pressure will be developed around the piles.As a result,the phenomena of soil squeezing in pile-sinking will do harm to the latter construction and the environment.The soil squeezing effect of the static pressure pile in pile-sinking is very distinctive.The large extrusion effect in pile-sinking drives the soil in pile area to heave and move horizontally,and the pile body to lift,to deviate,and to be broken off.This paper makes a simple analysis of the compacting effect by static piling and the development of the study of compacting effect at first;then analyzes the mechanism of soil displacement briefly,also,several mechanical problems concerning the compacting effect are studied in detail;in the end of the paper,the author sorts out and summarizes several popular engineering measures in design and construction for reducing the effect of soil squeezing of the static pressure pile at present,and proposes appropriate suggestions.