Performance evaluation of the fresh and hardened properties of different PVA-ECC mixes: An experimental approach

This paper aims to investigate experimentally the effect of two different polyvinyl alcohol (PVA) fibres (REC15×8 and RF4000×30) on the mechanical and physical properties of different mixes of Engineered Cementitious Composites (ECC). An effort has been made to overcome the issue of the high cost of ECC without compromising its tensile properties. For this purpose, three different types of ECC mixes (with and without coarse aggregate) have been investigated for varying dosages of fibre contents by volume (0%, 0.5%, 1%, 1.5% and 2%). Slump, density, compression, flexure, split tensile and ductility tests are performed for fresh and hardened concrete/ECC specimens. It has been revealed through experimental results that the workability of all the mixes decreased with the increasing percentages of fibres, however, it remained within the allowable range of ASTM for fibre contents of up to 2%. It was further observed that the ductile behaviour of ECC was greatly compromised with the use of coarse aggregate in the mix, however, strain hardening and multiple-cracking properties were found to remain intact. Mechanical properties (compressive, tensile, flexural strengths) were found to increase with increasing fibre contents up to a maximum dosage of 1.5%. Beyond 1.5%, a slight decrease in the mechanical properties for almost all the mixes was observed, thus 1.5% fibre contents were revealed to be the optimum dosage.