Developed triangular charts; deltaic CPTu-based soil behavior classification using AUT:CPTu-Geo-Marine Database

One of the crucial issues in foundation engineering is subsurface reconnaissance, especially for offshore and onshore structures. The cone and piezocone penetration tests (CPT and CPTu) are one of the most remarkable geotechnical in-situ tests for soil behavior classification (SBC) due to their capability, rapid performance, accuracy, and providing continuous records in depth. Since classifying soils in marine environments is accompanied by more uncertainty sources, the procedures of validation and evaluation for subsoil classification are enhanced by applying CPT and CPTu databases. Regardingly, a marine database of the CPTu soundings and soil profiling in their vicinity from offshore, onshore, and riverine areas was compiled. About sixty cases were considered for performance assessment of eight common soil behavioral classification methods. These methods were evaluated via a parameter introduced as success rate. The probability of successfully classifying various marine deposits was demonstrated through radar charts for the investigated database. It was revealed that the input parameters and the implemented correlations and assumptions have had a key role in soil deposit identification and reducing the embedded uncertainties. Eventually, the recently developed triangular chart was introduced, which implements CPTu soundings and more accurately divides soil deposits into seven zones compared to the investigated SBC methods.