High-strain rate compressive behavior of CFRP confined concrete: Large diameter SHPB tests

The behavior of a material under high-strain rate compression can be different from quasi-static one and can be determined by using the so-called Split-Hopkinson Pressure Bar (SHPB). The aim of this study is to investigate the high-strain rate compressive behavior of Carbon Fiber Reinforced Polymer (CFRP) confined concrete in comparison with unconfined concrete. A total of 112 specimens with a diameter of 150 mm were tested under quasi-static (with a length to diameter ratio of 0.5 and 2) and under high-strain rate axial compression (with a length to diameter ratio of 0.5 ) using a universal testing machine and a SHPB with a large diameter of 155 mm , respectively. The specimens were characterized by two different strength classes, namely C30 and C60, and by a different number of CFRP layers ranging from 0 (plain cylinder) to 3. Tests were executed up to a strain rate of 100 s - 1 . The measurements were validated by checking the consistency of the large diameter SHPB and by comparing the results of plain concrete with the data available in the literature. The results indicate that the strength of CFRP confined concrete is not significantly sensitive to strain rate effects.