Strength and deformation characteristics of engineered cementitious composite slabs with different polymer fibres

Abstract
This paper presents a study on the compressive and flexural strength of engineered cementitious composite (ECC) cubes and slabs, reinforced with various polymer fibres. The type of fibre, fibre content and aspect ratio were the parameters considered in this study. For all types of fibre, the compressive strength of the ECC decreased as the reinforcing index increased. For the ECC polypropylene fibre (PP) slabs, the first crack strength significantly decreased with an increase in the fibre content. For the ECC polyethylene fibre (PE) slabs, the first crack strength decreased as the reinforcing index increased. For the ECC PE slabs, the usage of PE 1600D fibres showed a substantial increase in flexural strength due to their higher tensile strength and E modulus. The ECC PP slabs behaved like plane concrete due to the zero value of flexural strength, which was attributed to the weak interfacial bonding with the cement matrix, low tensile strength and E modulus of the PP fibres. The highest ductility was observed for the ECC-PE slabs with the highest recorded deflection values; these values achieved many extended multiple cracks and an extensive area under the load–deflection curve indicating high energy absorption capacity.