Dynamic Response of Deccan Trap Basalt under Hopkinson Bar Test

The Deccan trap is a large igneous rock province located on the Deccan plateau of west-central India. There are several important structures located on Deccan trap basalt like Koyna dam hydropower project, Konkan railways, Katraj twin tunnels to name a few. In order to safeguard the structures from dynamic loading arising from manmade or natural disastrous circumstances, it becomes necessary to characterize the dynamic behavior of rocks. In the present work, experimental studies have been performed to determine the dynamic stress-strain behavior of Deccan trap basalt rock as the same is not yet available in literature. The rock samples have been collected from various regions spread along the Western Ghats in Maharashtra. Tests have been performed to determine the physical and static mechanical properties. The dynamic tests have been carried out using 20 mm diameter split Hopkinson pressure bar (SHPB) at different strain-rates. From the analysis of results, the dynamic stress-strain response of the rocks, force equilibrium and dependence of dynamic strength on the strain rate have been examined for the first time.