Non-destructive evaluation of the effects of exposure environment in mortars using non-linear ultrasonic measurements

• Published in: Developments in the built environment 2023-04, Vol.14, p.100142, Article 100142
• Main Authors: Ortega, José Marcos, Miró, Marina, Ibáñez-Gosálvez, Javier, Tenza-Abril, Antonio José
• Format: Article
• Language: English
• Subjects: Microstructure; Non-destructive characterization; Non-linear ultrasonic test; Non-optimum condition; Real environment
• ISSN: 2666-1659; 2666-1659
• DOI: 10.1016/j.dibe.2023.100142

The development of non-destructive techniques has currently a high interest, such as those based on non-linear ultrasonic measurements. In this work it has been assessed the possible application of non-linear ultrasonic measurements for getting information related to the microstructure and properties of Portland cement mortars exposed to real and non-optimum environments. The pore structure was studied using mercury intrusion porosimetry and differential thermal analyses. Mechanical strengths and linear ultrasonic pulse velocity were determined. Regarding non-linear ultrasonic measurements, the results of parameters R and DIFA were analyzed. The tests were performed at 28 and 250 days. At later ages, a loss of microstructure refinement and a worsening of mechanical performance of the mortars were observed. The results of non-linear ultrasonic parameters R and DIFA overall agreed with those obtained for the microstructural and mechanical characterization performed. In particular, an adequate correlation between parameter DIFA and the pore size distributions was observed. •Real and non-optimum environments produced a loss of pore structure refinement.•ParaMeters R and DIFA agree with microstructure and mechanical characterization.•There is an adequate correlation between parameter DIFA and pore size distributions.•NLU measurements are useful for studying the microstructure in real environments.•NLU parameters improved the information provided by classical linear UPV.