Durability indices of cracked slag-modified concrete under self-healing

• Published in: Sadhana (Bangalore) Vol. 48; no. 2
• Main Authors: Zeinali, Fereydoon, Rahmani, Hamid, Ahmadi, Jamal
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 03.06.2023
• Subjects: Engineering; slag-modified concrete; gap width; Self-healing; concrete durability
• ISSN: 0973-7677; 0973-7677
• DOI: 10.1007/s12046-023-02130-2

The present study investigated the durability indices of slag-modified concrete during the self-healing process. For this purpose, slag powder was substituted by 0, 15, 30, and 45% by weight of cement. Then, 28-day moist cured cylindrical specimens were prepared to investigate their autogenous self-healing ability. Two gaps with 100 and 200 microns were created in the specimens, and for re-curing, cracked specimens were exposed to tap water for another 28 days. RCPT, water passing, and electrical resistance tests were employed to evaluate the self-healing progress in the gaps and their durability indices. Moreover, XRD and SEM were utilized to achieve further information about the process of concrete self-healing. Results showed that the slag modified concretes can heal the wide gaps, and the self-healing ability improves by increasing slag substitution. Also, it is proposed that the durability of the self-healed slag modified concretes can be assumed more than that of the sound control concretes under chloride attack. Moreover, XRD and SEM observations revealed that a portion of portlandite was leaked into the curing water during the self-healing process.