CPT-based classification of soft organic clays and peat

An updated CPT-based classification system of organic clays and peat is proposed based on an extensive pairwise established database of classification tests and CPT measurements. This new classification system is proposed to supplement the existing dimensionless q_t/p_a-Rf-chart of Robertson (2010). The Robertson (2010) dimensionless classification system is selected for refinement because it appears to perform better than normalized systems for peats with very low stresses (<20 kPa). A combination with Robertson (2009 and 2016) is possible in cases where a stress normalization cut-off is used.