夯扩桩半模夯扩试验及夯扩机理探讨

设计了夯扩桩半模夯扩试验，采用读数显微镜直接测读上体质点位移，获得了不同密度的均匀砂土中砂粒的位移，由此确定土体的位移场和密度场。借鉴魏西克（Ｖｅｓｉｃ）球形孔穴膨胀理论和梅耶霍夫（Ｍｅｙｅｒｈｏｆ）塑性剪切理论，结合模型试验成果，对夯扩机理作了探讨，并定性地提出了夯扩机理模式。

Half Pile Model Tests of Compacted Base-enlarged Pile and the Analysis of the Action Mechanism

Half pile model tests of compacted base-enlarged pile are carried out in laboratory. The researchwork is Performed in uniform sandy soils with various density. The displacement field and the density field ofthe soil body are acquired through the soil particle's displacements measured directly with coordinate micro scope. On the basis of Vesic's spherical cavity expansion theory and Meyerhof's plastic shear theory, themodel of compacted base-enlarged action mechanism is proposed and analysed qualitatively, with the modeltests results taken into account.