Design and fabrication of fibrous media to facilitate autogenous smart self-healing properties in cracked-cementitious structures using polyethylene glycol (PEG) and silicon dioxide nanoparticles

Abstract

A novel approach is introduced for smart of cracked cementitious structures using a fibrous media occupied by polyethylene glycol (PEG) and silicon dioxide (SiO2) nanoparticles. A series of fibrous media were designed and fabricated using different fiber types (polyethylene terephthalate (PET), hollow polyethylene terephthalate (HPET) and polypropylene (PP)), areal densities, thicknesses and porosities. The fibrous media was filled by PEG/SiO2 nanoparticles to perform further hydration and then healing the crack by capillary rise of water into the cracked paths. An analytical model was proposed to predict the minimum critical crack radius in cementitious structure to initiate smart release of nano-particles through fibrous media. The developed model calculates minimum crack radius based on properties of polymeric components and associate media’s porosity with capillary rise of nano-particles in accordance with Washburn’s equation. An artificial neural network (ANN) based on multilayer perceptron (MLP) was used to determine the most important parameter influencing self-healing efficiency. The self-healing efficiency of samples were also evaluated via ultrasonic test, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS) and X-Ray diffraction (XRD) analyses. CaCO3 formation and C-S-H growth deducted from FESEM image analysis and EDS/XRD results. The PET media showed more healing efficiency because of less crack radius. The areal density parameter was found to be the most effective parameter in reducing the capillary radius. The new proposed method is simple and applicable to promote hydration and crack filling of cement products such as canvas concrete.