Self-healing characterization of UHPFRCC with crystalline admixture: Experimental assessment via multi-test/multi-parameter approach

Within the framework of Research Project ReSHEALience, new advanced Ultra High-Performance Fibre-Reinforced Cement Composites with enhanced durability, hereafter denoted as High Durability Concretes, are under investigation to characterize their tensile behaviour and durability performance in aggressive conditions, devoting particular attention phenomenon self-healing. Three different mixes scrutiny, based on combination cement (CEM I or CEM III), slag, small aggregates (sand a maximum size 2 mm), steel metallic-alloy amorphous fibre. Self-healing capability has been investigated environment (namely, immersion geothermal water) via 3 test setups: (1) water permeability pre-cracked concrete disks, (2) 4-Point Bending Test – 4PBT 100 × 500mm3 prismatic beam specimens (3) 25 thin beams. In case beams, self-healing assessed visual inspection cracks trough digital microscope mechanical re-loading, so investigate both crack-sealing recovery. The results this assessment aim at providing starting point for data base finalized defining design approach explicitly taking into account evaluation structural durability. particular, it observed adoption strain-hardening composites significantly promotes phenomenon, thanks smeared cracking region consequent low values crack opening. proved be very effective already after 1 month curing.