(1. School of Civil and Transportation Engineering，Guangdong University of Technology，Guangzhou，Guangdong 510006，China； 2. Shenzhen Graduate School，Harbin Institute of Technology，Shenzhen，Guangdong 518055，China；3. School of Civil Engineering，Hefei University of Technology，Hefei，Anhui 230009，China；4. College of Civil Engineering and Mechanics， Lanzhou University，Lanzhou，Gansu 730000，China)
Abstract：A hydraulic gradient test device was used to conduct a model experiment and to study the pile-soil interaction. In this model test，the seepage field and gravity field simulate the in-situ stress field，the deformation pictures of soil are captured with the use of a high resolution camera，and the soil displacements are obtained using the particle image velocimetry technique. The mechanical properties of the model pile and the distribution characteristics of the displacement field of soil around the laterally loaded pile are visually studied. The laterally loaded pile was studied at the hydraulic gradient of i = 0，i = 5 and i = 10. As the hydraulic gradient increases，the displacements of the pile and the sand particles decreased，the influence zone of the pile shrank，and the depth of the rotation point of the pile was uplifted. The underlying reason for the changes is that the seepage increased the stiffness of the soil. As a result，the relative stiffness ratio between soil and pile increased，leading to a stronger pile-soil interaction.
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2016, Vol. 35 
