Ultrasonic wave attenuation as a tool for estimating frost action on limestone rocks

Observations about the evolution of damage to limestone during freeze/thaw cycles using ultrasonic methods (involving wave velocity and attenuation) help understand the physical mechanisms which give rise to damage under frost action. The ultrasonic methods commonly applied rely on theoretical models of frost propagation in porous media and are based on thermodynamic considerations and on capillarity theory. Under the necessary conditions of rock damage formation, i.e. high degrees of saturation and negative temperatures, the geometry of the porous network constitutes the dominant factor which determines the nature of the resulting damages. This parameter controls the degree of saturation of materials both in structural work and under natural conditions. The degree of saturation is among the major factors which aggravate frost degradation of limestone at temperatures below 0 degreesC. Data supplied by the recordings of ultrasonic wave attenuation in limestone during freeze/thaw cycles help characterise and identify, the different types of damage.