Durability and mechanical characteristics of self healing fiber reinforced concrete

The durability of concrete structures is a critical aspect of sustainable infrastructure, and the incorporation of self-healing mechanisms has gained significant attention in recent years. This study presents a comprehensive study on the durability of self-healing concrete using a combination of crystalline admixture and fly ash as a mineral admixture and nylon fibers. The research focuses on the effectiveness of crystalline admixtures in promoting autonomous crack healing in concrete, while fly ash enhances the overall durability characteristics whereas nylon fibers to enhance the tensile characteristics of concrete. Studies on selfhealing of concrete have been done for M70 grade but the current research is focussing the study on M25 to check the efficiency of the crystalline admixture on lower grades of concrete. In the present investigation, the healing properties of cracked concrete varying is analyzed by varying the nylon fibers in o.5 %, 1%, 1.5%, keeping the optimum fly ash percentage as 15%, and using 1.1% crystalline admixture. The mechanical properties of the healed concrete are determined before crack formation and after crack healing. Furthermore, the research examines the influence of fly ash as a mineral admixture on the durability aspects of self-healing concrete by performing various tests such as acid resistance test and alkali resistance test. The inclusion of a 1.1% crystalline admixture, 15% fly ash, and 0.5% nylon fibers in concrete has shown significant benefits in terms of regaining compressive strength and split tensile strength. After a healing period of 28 days, the material’s compressive strength improved by 63.78%, while the split tensile strength increased by 62.57% when compared to the control mix. And also when immersed in acid and alkali solutions the same mix showed minimal weight loss and percentage of strength loss.