Title: Natural Fibres As Promoters Of Autogeneous Healing In HPFRCCS: Results From On-Going Brazil-Italy Cooperation

Author(s): Liberato Ferrara; Saulo R. Ferreira; Visar Krelani; Marco della Torre; Flavio Silva and Romildo D. Toledo Filho

Publication: Symposium Paper

Volume: 305

Issue:

Appears on pages(s): 11.1-11.10

Keywords: self healing, HPFRCCs, natural fibers, deflection hardening/softening, delayed hydration, carbonation, DTGA

DOI: 10.14359/51688571

Date: 9/1/2015

Abstract:
Natural fibres are a waste product of food and agriculture industry to which a great potential of use as dispersed reinforcement in cementitious composites has been recognized, making them a valuable source of income for developping communities and countries, where they are abundant and can be harvested with minor investments. A further value to the use of natural fibres in cementitious composite as promoters and facilitators of self healing has been recently confirmed by preliminary investigations. Thanks to their microstructure, natural fibres are able to create a porous network through which the moisture can be distributed throughout the cementitious matrix and activate the delayed hydration reactions which, together with carbonation ones, can be responsible of the autogeneous healing of cracks. The authors have undertaken a comprehensive experimental programme to investigate the efficacy of different types of natural fibres, when used in combination with industrial fibres (steel), to promote and enhance the self healing reactions in HPFRCCs. Influence of environmental conditions has also been studied. The effects of self healing on the recovery of flexural performance has been quantified; healed cracks and effects of healing on fiber matrix bond have been visualized through optical digital microscopy.