Mechanical properties of high-strength steel-polyvinyl alcohol hybrid fibre engineered cementitious composites

With the advancement of material technology, the use of high-strength and high-performance materials in the construction industry is gaining popularity. Steel-polyvinyl alcohol (steel-PVA) hybrid fibre engineered cementitious composites (ECC) is one of such high-performance class of construction materials whose mechanical properties are not well studied in the literature especially in high-strength matrix. Therefore, in this paper, the mechanical properties of four different grades of high-strength steel-PVA ECC are experimentally investigated. ECC with nominal compressive strengths from 60 to 100 MPa are developed. Their mechanical properties including compressive and tensile stress-strain behaviour, elastic modulus and toughness are studied with particular focus on high-strength matrix. Test results show that the developed steel-PVA ECC could achieve good tensile (~0.8%) and compressive (~0.5%) ductility for general structural applications. Simple empirical relationships to predict the elastic modulus and tensile strength of the developed steel-PVA ECC as a function of their compressive strength are suggested. Moreover, an analytical model to generate a complete compressive stress-strain curve of the high-strength steel-PVA ECC is proposed and verified against the experimental results. The proposed stress-strain model would present a useful reference for non-linear analysis of structural elements utilising steel-PVA ECC.