Self-healing assessment and variability in plain and recycled tyre fiber reinforced concrete based on tensile splitting test

Abstract

This research investigates the objectivity of current methodologies to assess self-healing ability in Fiber Reinforced Concrete (FRC) when compared to a traditional Reference Concrete (REF). FRC was obtained by partially substituting of natural aggregates with Electric Arc Furnace Slag (EAFS) and Fly Ash (FA), and Recycled Tyre Steel Fibers (RTSF) were incorporated in order to maximize the incorporation of non-biodegradable waste. Self-healing was evaluated by measuring the water permeability and by visual inspection of cracks, with both a digital microscope and the use of a Linear Variable Differential Transducers (LVDTs) during the tensile splitting test. The results of this assessment are intended to provide improvements in self-healing assessment methodologies based on cracking imaging and the water permeability test. The composition of the FRC_EAFS concrete, with a maximum EAFS and FA content of 70% and 10%, respectively, had lower compressive and tensile splitting strength compared to the REF concrete, which was compensated by the improved ductility and energy absorption capacity under compressive loading. Permeability recovery was only accomplished by REF mixture.