Effects of strain rate on mechanical behavior of modeled recycled aggregate concrete under uniaxial compression

摘要

This paper reports the experimental study of strain-rate effects on the mechanical behavior of modeled recycled aggregate concrete (MRAC) under uniaxial compressive loading with strain rates ranging from 10-5/s to 10-1/s. The failure pattern, peak stress, peak strain and elastic modulus of MRAC are analyzed to assess the strain-rate sensitivity. Different types of MRAC specimens are tested to investigate the effects of quasi-static strength and modeled recycled coarse aggregate (MRCA) replacement ratio on the strain-rate sensitivity of MRAC. With the increase of strain rate, the peak stress and elastic modulus increase while the peak strain shows no clear trend. The effects of strain rate on low strength MRAC are more significant than that of high strength MRAC. As the strain rate increases, cracks grew more rapidly and there were always several main cracks running through the MRAC specimens at a high strain rate, resulting in fewer cracks than under quasi-static loading.