Cone angle influence on dynamic light cone penetrability and its effect on tip resistance prediction

Dynamic cone penetration test has numerous advantages over commonly adopted static cone penetration test for ground characterisation. However, the major setback of the test is being unable to sorely characterise the ground. Currently, the test is used for strata boundary identification. The current focus of researchers is on the correlation within the dynamic cone tests (such as dynamic light cone penetration test (DPL) versus standard cone penetration test (SPT)) or between dynamic cone tests (DPL) and static cone penetration test (CPT). The influence of the cone angle among these correlations is overlooked. Diversification from standardised equipment (especially on the cone angle) affects the effort rendered to the interpretation of the DPL. The article aims to unveil the existence of the cone angle and soil shear parameters interaction for consideration among researchers and practitioners. A columnar square chamber of 0.9 m × 0.9 m and height of 10 m was used, together with the 35.7 mm and 24.7 mm cone diameters, each with a set of four cone angles (30°, 45°, 60° and 90°) that were adopted. Cone penetration through slightly/none-cohesive and cohesive SAND soils was assessed. The experimental results reveal that cone angle and soil cohesiveness affect the cone penetrability. The cone angles to shear soil parameters for none-cohesive soil are prognostic, contrarily to cohesive soil. The Weisner equation provided in the standards such that BS EN ISO 22476–2:2005 for tip resistance prediction is modified to include cone angle influence.