Dynamic mechanical behavior and damage properties of SHCC under high strain rate loading

Abstract

Dynamic mechanical behaviors of strain-hardening cementitious composites (SHCC), considering the influence of strain rates, were investigated using split Hopkinson pressure bar (SHPB). Full-field strain evolution and cracking behavior of SHCC under high strain rate loading were investigated using high-speed digital image correlation (DIC) technology. Additionally, the damage properties of SHCC induced by high strain rate loading were analyzed using X-CT images and SEM observation. The results show that dynamic peak stress, strain, energy absorption capacity and dynamic increase factor (DIF) of SHCC are increased with the increase of strain rate. Full-field strain evolution of SHCC during the SHPB test demonstrates that the expansion in the vertical is larger than compression in the lateral under high strain rate loading. According to the X-CT images, dynamic load with a relatively higher strain rate will induce more fine cracks, and the number of cracks inside the specimen is more than on the surface. Moreover, plastic deformation of PVA fibers occurs under high strain rate loading based on SEM observation.