Characterization of multi-scale porosity in cement paste by advanced ultrasonic techniques

• Main Authors: Wonsiri Punurai, Jacek Jarzynski, Jianmin Qu, Jin Yeon Kim, Laurence J. Jacobs, Kimberly E. Kurtis
• Other Authors: Georgia Institute of Technology
• Format: Article
• Published: 2018
• Subjects: Engineering; Materials Science
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/24454
• Institution: Mahidol University

The effectiveness of advanced ultrasonic techniques to quantitatively characterize the capillary porosity and entrained air content in hardened cement paste is examined. Direct measurements of ultrasonic attenuation are used to measure the volume fraction and average size of entrained air voids and to assess variations in intrinsic porosity - as influenced by water-to-cement ratio (w/c) - in hardened cement paste samples. For the air entrained specimens, an inversion procedure based on a theoretical attenuation model is used to predict the average size and volume fraction of entrained air voids in each specimen, producing results in very good agreement with results obtained by standard petrographic methods and by gravimetric analysis. In addition, ultrasonic attenuation measurements are related to w/c to quantify the relationship between increasing porosity (with increasing w/c) and ultrasonic wave characteristics. © 2006 Elsevier Ltd. All rights reserved.