Use of Image Processing Techniques to Investigate the Behaviour of Driven Piles

Abstract

Steel driven piles having either open-ended and closed ends have been used widely in onshore and offshore pile foundations. But the behaviour of open-ended piles is complicated than closed-end piles due to the formation of soil clogging phenomenon. The current work examines the effect of pile dimensions and its related clogging behaviour through image analysis. Solid and hollow half-section aluminium piles of different elastic modulus and dissimilar cross-sectional areas are used for the study. A scaling factor of 10 has been used for modelling the pile. The modelled piles are subjected to Standard Penetration Test (SPT) which simulates the application of impact loads in crushed stones (4.75-2.36 mm) of various soil densities. The experimental progression is grabbed through the digital single-lens reflex camera and sequential pictures captured during the test are analyzed through open-source software GeoPIV which is based on Digital Image Correlation technique (DIC). The GeoPIV software helps in measuring deformation behaviour and strain path over a Region of Interest (ROI). The examination of DIC test results revealed that for hollow piles there is a surge in volumetric shear strain contours about pile shaft region. This could be due to the soil plug formation at the tip of hollow pile irrespective of infill density. For solid piles, strain concentrations are observed closer to pile head due to its greater flexural rigidity than hollow piles.