Next Article in Journal
Enhancing the Fracture Toughness Properties by Introducing Anchored Nano-Architectures at the Metal–FRP Composite Interface
Previous Article in Journal
Bending, Free Vibration, and Buckling Analysis of Functionally Graded Porous Micro-Plates Using a General Third-Order Plate Theory
Article Menu

Export Article

Open AccessArticle

Monitoring the Self-healing of Concrete from the Ultrasonic Pulse Velocity

Department of Civil Construction, Federal University of Parana, Curitiba, PR 81530-000, Brazil
*
Author to whom correspondence should be addressed.
J. Compos. Sci. 2019, 3(1), 16; https://doi.org/10.3390/jcs3010016
Received: 28 December 2018 / Revised: 30 January 2019 / Accepted: 31 January 2019 / Published: 2 February 2019
(This article belongs to the Special Issue Self-Repairing Composites)
  |  
PDF [1000 KB, uploaded 2 February 2019]
  |  

Abstract

Concrete has the ability to naturally heal its cracks, in a process called self-healing. This article aimed to analyze the self-healing of concretes, evaluating the influence of fly ash and the age of occurrence of cracks. Concrete specimens were submitted to cracking at 7 and 28 days. Subsequently, the samples were exposed to 12 wetting and drying cycles in order to favor the self-healing process. The phenomenon was evaluated through the ultrasonic pulse velocity testing, performed weekly on the specimens from the molding stage until the end of all cycles. The concretes showed a decrease in ultrasonic pulse velocity at the time they were cracked. This is due to the greater difficulty in the propagation of ultrasonic waves in the voids formed during cracking. This drop was higher for concrete with fly ash. Also, the results show that the fly ash concretes presented a more expressive self-healing process when cracked at 28 days, which may be related to the presence of pozzolanic reactions and the presence of more anhydrous particles. The concretes without fly ash had self-healing when they were cracked at 7 days. This is explained by the high hydration rate characteristic of ordinary Portland cement. View Full-Text
Keywords: self-healing; ultrasonic pulse velocity; fly ash self-healing; ultrasonic pulse velocity; fly ash
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Camara, L.A.; Wons, M.; Esteves, I.C.; Medeiros-Junior, R.A. Monitoring the Self-healing of Concrete from the Ultrasonic Pulse Velocity. J. Compos. Sci. 2019, 3, 16.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
J. Compos. Sci. EISSN 2504-477X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top