The American Concrete Institute (ACI) has released a paper on experiments conducted to evaluate the acoustoelastic behaviour of concrete under uniaxial compression.
In the paper, Acoustoelastic Response of Concrete under Uniaxial Compression, third-order acoustoelastic parameters were experimentally determined for 14 specimens made with 10 different mixtures (nine concretes and one mortar). This was done using ultrasonic pulse velocity measurements of waves propagating perpendicularly to load direction.
In the second part of the study, acoustoelastic stress-strain relations, based on Murnaghan third-order parameters determined in the experiments, were used to model concrete behaviour and to evaluate changes in concrete elastic properties.
ACI says: “Results demonstrate the relevance of the acoustoelastic effect in concrete mechanical behavior and proves that concrete becomes anisotropic due to the acoustoelastic response (acoustoelasticinduced anisotropy).”
This paper was written by Carnot L. Nogueira and Kevin L. Rens.