(1. Faculty of Architectural，Civil Engineering and Environment，Ningbo University，Ningbo 315211，China；2. Geotechnical Research Institute，Hohai University，Nanjing 210098，China；3. Department of Civil Engineering，Zhejiang University City
College，Hangzhou，Zhejiang 310015，China；4. Geotechnical Engineering Research Center，Tianjin Research
Institute for water transport engineering，M.O.T.，Tianjin 300456，China)
Abstract：A small-scale 1-g physical modeling under unconfined condition，using transparent soil，was employed to observe the complete curves of buckling of fully embedded slender piles with different constraint types. Meanwhile，the soil deformations caused by buckling of slender pile were measured non-intrusively by combining particle image velocimetry(PIV) and close-range photogrammetry. The transparent soil was made of fused quartz and correspondingly refractive index matched blended oil. Transparent soil model was sliced using a laser light sheet，and digital images of soil deformations，caused by buckling of slender pile，were recorded. PIV was utilized to obtain the generated displacement fields. Analysis of test results shows that the relative buckling length increases with the increasing of pile strength and decreasing of slenderness ratio；the effect of end constraint types of pile on buckling curves is dependent on the variations of pile strength and slenderness ratio；the movements of soil elements agree well with the classic Rankine?s earth pressure theory.
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2015, Vol. 34 
