ABSTRACT
Compression and ultrasonic pulse tests were carried out on high-toughness cementitious composites (HTCC) after dry-wet cycles. Special focus was centered on the stress-strain relation and the corresponding variation of wave velocity under different water immersion cycles. The results show that the initial P wave velocity and S wave velocity of HTCC was kept almost unchanged at the early stage of immersion. As the immersion period extended, P wave velocity during loading gradually exhibited a “compacting” characteristic. On the other hand, HTCC, at the early immersion stage, experienced a steep drop in S wave velocity during loading. However, the steep drop degree tended to be moderate with the immersion cycle, and the associated failure mode was gradually translated from a nonsteady state into a steady state. It turns out that the ultrasonic pulse method can effectively identify the compression damage and characterize the failure mode of HTCC.
