Improved ultrasonic wave reflection technique to monitor the setting of cement-based materials

A test setup using the ultrasonic wave reflection technique is used to monitor the hydration process of early-age cement-based materials throughout their setting and hardening. The focus of the investigation presented here is the monitoring of the stiffening behavior of cement pastes. Specimens are produced and kept under constant curing conditions. Immediately after placing the cement paste the data collection starts and continues throughout the setting process. The obtained ultrasonic data are correlated to mechanical and chemical properties of the specimens. The results illustrate that the applied experimental wave reflection technique is suitable to monitor the stiffening of cement pastes accurately. (c) 2005 Elsevier Ltd. All rights reserved.