An experimental study of high strain-rate properties of clay under high consolidation stress

Abstract

A split Hopkinson pressure bar (SHPB) combined with high pressure consolidation apparatus and high speed camera was used to obtain dynamic compressive stress-strain curves of clay whose over consolidation stress state in the process of formation was properly considered. The stress-strain relationship at various high strain rates from 60s−1 to 600s−1 was obtained. The strain rate and degree of consolidation effects on the compressive response of the consolidated clay were determined. The results show that the dynamic mechanical properties of clay in high pressure consolidation is sensitive to strain rate, and parameters like dynamic strength, failure strain and so on are significantly improved compared with unconsolidated clay which indicate that the initial stress history of the soil materials is also one of the most important factors that affect the dynamic mechanical response.