Eco-friendly modified engineered cementitious composites: a study on mechanical, durability and microstructure characteristics

Abstract

This research examined the development of modified engineered cementitious composites (MECC) using manufactured sand (M-sand) and a high content of raw agricultural by-products, such as bagasse ash (BA) and rice husk ash (RHA), instead of conventional silica sand and fly ash. Fourteen different types of MECC mixtures were developed using raw BA and RHA blended with M-sand to reduce the cost of MECC. The fresh and hardened properties of all mixtures were examined using various types of testing methods. In addition, microstructure analysis were conducted for both the control and optimal mixtures to identify the bonding of fibres in cementitious composites. The correlation between conventional and MECC was also evaluated based on the hardened properties and cost analysis. The results revealed that workability steadily dwindled with increasing percentages of BA and RHA, from 10 to 55. Optimal mechanical properties were attained with the incorporation of BA and RHA at 10% cement replacement. In contrast, 30% BA and 40% RHA exhibited maximum impact strength compared to the respective control mixes. Similarly, ECC with 20% BA and RHA exhibited optimal durability properties. Moreover, compared to conventional ECC, the cost of the newly developed MECC was slightly lesser due to the incorporation of agricultural by-products and M-sand.