Mechanical properties and self-healing mechanism of epoxy mortar

• Main Authors: Ariffin, Nur Farhayu, Hussin, Mohd. Warid, Mohd. Sam, Abdul Rahman, Han, Seung Lee, A. Khalid, Nur Hafizah, Abdul Shukor Lim, Hasanah, Samadi, Mostafa
• Format: Article
• Language: English
• Published: Penerbit UTM Press 2015
• Subjects: TA Engineering (General). Civil engineering (General)
• Online Access: http://eprints.utm.my/id/eprint/56092/1/MohdWaridHusin2015_MechanicalPropertiesandSelf-HealingMechanism.pdf; http://eprints.utm.my/id/eprint/56092/; http://dx.doi.org/10.11113/jt.v77.6306

Crack deformation in concrete start with hairline crack or micro-crack which can lead to major crack if not prevented. Crack can cause a major deterioration to the structure as liquid can penetrate inside and cause damage as a result; the durability of concrete will decrease. Self-healing concrete was introduced to automatically repair hairline crack or micro-crack without external intervention. Previous study had shown that by introducing bacteria into the concrete, the crack will heal itself. This paper presents the study on self-healing mortar by using epoxy resin without hardener as a self-healing agent. The self-healing process was evaluated using Ultrasonic Pulse Velocity measurements up to 180 days. Mortar specimens were prepared with mass ratio of 1:3 (cement: fine aggregate), water-cement ratio of 0.48 and 10% epoxy resin of cement content. All tested specimens were subjected to wet-dry curing; where compressive strength, flexural strength, and tensile splitting strength and self-healing mechanism were measured. The results obtained shows that, all strength properties of the self-healing epoxy mortar were significantly higher than the control sample and became constant at 10 % of epoxy resin content. Based on the pulse velocity measurements, after 60 days the cracks of the mortar healed automatically as a result of the reaction between the unhardened epoxy resin and hydroxyl ion from cement