Technological performance of acai natural fibre reinforced cement-based mortars

Acai (Euterpe oleracea Mart.) is a fruit from forests typical of South American countries, such as Brazil. The fruit is harvested from palm trees and later processed to produce several food and aesthetic products that bear considerable health benefits. The processing of acai generates substantial amounts of waste, such as natural fibres, which are generally disposed of in landfills. The objective of this work is to evaluate the technological performance of adding acai fibre (with additions of 1.5%, 3.0% and 5.0% relative to cement mass) in its natural condition and after surface treatment with NaOH in mortars based on cement and lime. Acai fibre was physically, chemically and microscopically characterised. The properties of consistency, water retention, incorporated air content, mechanical strength (compression and flexion), mass density (fresh and hardened state), capillary water absorption and durability (wetting and drying cycles) were analysed as well. Results show that acai fibres in additions of up to 3.0% relative to cement mass and properly treated with NaOH solution can be used as reinforcement mechanism for mortar applications.