Matrix cracking repair and filling using active and passive modes for smart timed release of chemicals from fibers into cement matrices

Abstract

Concrete and cement permeability (due to cracking and porosity) and brittleness can be addressed by the incorporation of chemicals in fibers, which are later released. This changes the material matrix properties just in time to prevent and repair damage. The conventional method to reduce cracking is fiber reinforcing and permeability is reduced by sealants and waterproofers or creation of a tighter microstructure of fewer, smaller pores. Our research combines the fibers and sealants together for internal timed release of chemicals from hollow fibers. This research specifically concerns the repair or healing of cracks and filling of voids in cementitious matrices by the internal release of repair chemicals from inside fibers into the hardened matrix. Two active and one passive mode of activation are studied.