Global assessment of concrete specimens subjected to freeze-thaw damage

Abstract

Freeze-thaw damage is one of the main deleterious processes of concrete in cold climates. This study intends to detect the ongoing freeze-thaw (FT) deterioration in concrete specimens through the use of the global assessment combining the results of the mechanical and microscopic evaluation, pressure tension (PT) and compressive strength test as well as the Damage Rating Index (DRI), respectively. Concrete specimens displaying two w/c ratios (i.e., 0.65 and 0.45) were cast and subjected to FT cycles (i.e., 1, 5, 10, 20 and 30) and later the mechanical and microscopic assessments were conducted. Results show that PT and DRI are effective and reliable techniques to evaluate the condition of FT-affected concrete displaying various microstructures, since the PT test captures the damage at a very early stage of FT deterioration and DRI could identify important distress features at various stages of FT-affected concrete. Ultimately, the diagnostic nature of the PT test has been validated through the use of DRI.