Title: Effect of Mineral Additions on The Self-Healing Ability of Cementitious Materials

Author(s): Carol Namnoum, Benoît Hilloulin,Maxime Robira, Frédéric Grondin, Ahmed Loukili

Publication: Symposium Paper

Volume: 349

Issue:

Appears on pages(s): 1-14

Keywords: Autogenous self-healing, ground granulated blast furnace slag, metakaolin, mechanical properties, SEM/EDX, TGA, XRD

DOI: 10.14359/51732734

Date: 4/22/2021

Abstract:

The production of cement by calcination of limestone releases large amounts of carbon dioxide. Development of concrete quality lead to optimize the sustainability and maintenance phases of concrete structures, so, using supplementary cementitious materials (SCM) is one of the methods adapted to reduce the environmental impact of cement production. In addition, self-healing of concrete appears as a process to considerably improve the durability of a damaged structure [1]. As revealed by most analyses, mineral additions can be used to improve the autogenous healing ability of cementitious materials [2].

In this study, the influence of using a combination of SCMs, such as ground granulated blast furnace slag and metakaolin, on the mechanism of autogenous crack healing was assessed in ternary formula. Self-healing evolution was characterised by means of mechanical tests carried out on notched mortar samples with different substitution ratios. The mechanical recovery was investigated after the healing period. Moreover, the micro-chemical structure of the healing products was determined using various techniques (TGA, SEM/EDS and XRD). The primary results showed that using metakaolin and ground granulated blast furnace slag together greatly improve the healing efficiency.