Dynamic Mechanical Properties of Self-Compacting Rubberized Concrete under High Strain Rates

Abstract

Self-compacting rubberized concrete (SCRC), as the primary material of road construction, is produced by adding rubber particles instead of sand to self-compacting concrete (SCC). Four kinds of concrete with different rubber contents (0%, 5%, 10%, and 15%) are tested in this study. The materials testing systems (MTS) and split Hopkinson pressure bar (SHPB) are employed to obtain quasi-static mechanical properties (compressive, splitting tensile, and bending) and dynamic mechanical properties at high strain rates (100–250 s−1). The results reveal that quasi-static mechanical strength decreases with the increase in rubber content. Compared with SCC, SCRC is dramatically high in ductility. With the increase of the strain rate, the dynamic compressive strength, peak toughness, specific energy absorption (SEA), and dynamic increase factors (DIF) all rise. The dynamic compressive strength decreases with the ascending of rubber content, while the toughness index, peak toughness, and SEA increase with the increasing rubber content. Exponential and linear fittings are utilized to help further understand the influence of strain rates. The craze-shear band-cavitation theory can also help well explain the transition strain rate of peak toughness curves. The failure modes under high strain rates are observed. The results reveal that SCRC exhibits a stronger sensitivity to rubber content and has better impact toughness than SCC.