A laboratory study of cone penetration resistance in dry sand using a miniature solid cone

Abstract

This research has been conducted as a preliminary study to develop a miniature cone and its applicability for future use with special attention to liquefaction susceptibility. Previous studies have shown that Static Cone Penetration Test (CPT) results. can be used successfully to derive information on soil types and strength. Owing to this fact, this research is performed to try to correlate the cone penetration resistance with the density of the sand and to check the validity of formulas derived from previous works related to prediction of cone tip bearing resistance qc , in normally consolidated sand. For this purpose, a large sample of sand is prepared in a box of (.61mx.61m) and 4'(1.22 m) high using a funnel with adjustable diameter and dropping height as to produce diferent densities of the sand. The CPT is performed using two solid miniature cones, one with 0.625 in (15.875 mm) diameter (Cone 1) and the other with the same diameter shaft but with enlarged tip of .825 in. (20.955 mm) (Cone 2). The results are compared to predicted values of qc or angle of internal friction using the available theories. From the comparison, it is concluded that Schmertmann's experimental equation best fitted the data and that the angle of internal friction varies with depth. In addition, review on the factors influencing the cone penetration resistance are presented to help anticipate the predictions and understanding of the penetration test phenomena.