Thin soil layer detection by VisCPT and FEM simulations

A comprehensive approach for locating, characterizing the dominant grain size and estimating the strength of thin anomalous layers in a cohesionless soil stratigraphy is presented. The approach utilizes the results of finite element simulations of cone penetration across thin layers of anomalous strength and identification of their location and thickness using the Vision Cone Penetrometer (VisCPT). Through developed image processing algorithms based on wavelet decomposition, the dominant grain size in soil images is obtained. FEM simulations utilizing adaptive remeshing reveal the changes in CPT tip resistance across thin layers. Field data confirms the VisCPT’s ability to detect thin layers that are often missed by the conventional CPT. RÉSUMÉ Une approche globale de la localisation, la caractérisation de la taille des grains dominante et l'estimation de la force de couches minces anormale dans un sol cohesionless stratigraphie est présenté. L'approche utilise les résultats de simulations par éléments finis de la pénétrabilité au cône à travers des couches minces de force et de l'identification des anomalies de leur emplacement et de l'épaisseur à l'aide du cône Pénétromètre Vision (VisCPT). Grâce à des algorithmes de traitement d'image développé repose sur la décomposition en ondelettes, la dominante la taille des grains dans le sol, les images obtenues. FEM simulations utilisant remaillage adaptatif révèlent les changements dans CPT pointe à travers la résistance des couches minces. Les données de terrain confirme l'VisCPT de la capacité de détecter des couches minces qui sont souvent manqués par l'conventionnel CPT.

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