Effectiveness of wave interferometry in monitoring strength and stiffness development of early-age concrete

Abstract

With the aim of developing a nondestructive technique for monitoring the progression of the strength and stiffness of early-age concrete, this research investigated the effectiveness of wave interferometry in such applications. Lab-scale concrete specimens with a water/cement ratio of 0.45 were cast and subjected to water or air curing. The microstructural evolution of early-age concrete along the curing process was characterized by employing ultrasonic and mechanical parameters. The wave interferometry results showed that the relative velocity change had a gradual increase of 8.9% and 5.2% from 1 to 28 days of curing in water- and air-cured samples, respectively. Accordingly, the relative velocity change exhibited a strong correlation with the compressive strength as well as the modulus of elasticity. In addition, wave interferometry sensitively differentiated the effects of the two curing methods.