Dynamic mechanical behavior of geomaterials has been widely observed in tunneling, oil and gas extraction, and blasting in civil and mining applications. It is important to understand how much energy is necessary to break or fail geomaterials to optimize the design of blasting patterns, oil and gas extractions, demolition, military defense, etc. However, there is little understanding for quantifying the required energy to break geomaterials under dynamic loading. More importantly, as typical geomaterials tend to hydrate, it is necessary to understand how much energy will be needed to break the structures under water saturation. Thus, in this study, we analyzed the consumed energy used to deform geomaterials using a split Hopkinson pressure bar (SHPB), enabling to measure stress and strain responses of geomaterials under dynamic loading condition of high strain rate (102–104/sec). Two different saturation levels (dry vs. fully saturation) in two sandstone samples having different pore sizes were tested under dynamic loading conditions. Our results demonstrate that dynamic mechanical strength (maximum stress) is greater in the dry geomaterials when compared with the saturated samples, and Young’s modulus (or maximum strain) can be a useful parameter to examine porosity effects between dry and saturated geomaterials on dynamic mechanical properties.
Dynamic tensile strength enhancement of concrete in split Hopkinson pressure bar test
