In this study, the hardening process of ultra high performance concrete (UHPC) was monitored non-destructively using a single embedded sensor system. The propagating characteristics of guided waves obtained from the sensing system were analyzed to estimate the setting time and the
strength development of UHPC. Since the boundary conditions of the embedded sensor system continuously change during the hardening process of concrete materials, the hardening process can be monitored based on the measured characteristics of the propagating waves. To understand the variations in wave propagation, the modes for the guided waves were decomposed. The strength development of UHPC, with and without short-fiber reinforcement, was estimated using the variation of patterns of the decomposed wave modes. Based on the proposed methodology, which measures the propagation and variation of the guided waves, it is possible to estimate the time of phase transition and the strength development of UHPC.
Kim, S. B., & Sohn, H. (2006) Baseline-Free Crack Detection in Steel Structures using Lamb Waves and PZT Polarity, Journal of Earthquake Engineering Society of Korea, 10, 79–91.
Rose, J. L. (2014) Ultrasonic guided waved in solid media. New York: Cambridge University Press.