Dynamic compression property of polyvinyl alcohol (PVA)/engineered fiber reinforced cementitious composite (ECC) with different length-diameter ratios

The dynamic compression properties of engineered fiber reinforced cementitious composite (PVA/ECC) with different length-diameter ratio and different polyvinyl alcohol (PVA) fiber contents by volume subjected to four different strain rates were investigated by using a 50 mm diameter split Hopkinson pressure bar (SHPB). The results show that PVA/ECC specimens with larger length-diameter ratio (l/D>1.0) are more prone to directional slip failure after impact compression damage. Furthermore, the length of plateau period of stress-strain curve is obviously shortened and the area surrounded by the curve is also significantly reduced. The dynamic peak stress, peak strain and impact toughness of PVA/ECC decrease significantly with the increase of length-diameter ratio, which reveals the existence of a certain size effect, and that the higher the strain rate or the smaller PVA fiber contents by volume is the more obvious the influence of length-diameter ratio will be. The strain rate effect of PVA/ECC specimens with larger length-diameter ratio may become not obvious, but the strengthening effect of PVA fiber become more obvious, which effect is the most significant on impact toughness.