Sustainable Engineered Cementitious Composite using Natural Sisal and Coir Fibers

Abstract

Engineered Cementitious Concrete (ECC) or bendable concrete is a high-performance concrete (HPC) with high ductility characteristic. Generally, it has been used to strengthen or retrofit existing structures to increase structural resilience against extreme loadings such as earthquakes or blasts. The constituent materials of ECC are fine aggregates, cement, supplementary cementitious composite (silica fume, fly ash, etc.), superplasticizer, water, and the use of fibers up to 2% volume fraction. With the use of fibers and the elimination of coarse aggregate, ECC has deflection-hardening in bending and exhibits fiber-bridging by multiple cracking. However, the development of ECC has so far been limited to using only synthetic and inorganic fibers, which are scarce yet expensive in Indonesia. As Indonesia boasts the second highest level of biodiversity in the world as the source of natural fibers, in this research, the natural fibers are used to replace synthetic and inorganic fibers in making ECC more sustainable, low cost yet locally available. Not only did the natural fibers are locally available at affordable prices, but the fibers also have distinctive characteristics of sustainable materials with high tensile strength and significant elongation. From the experiments, one may be concluded that natural fibers of sisal and coir can improve the ECC flexural strength up to 39.5% of the non-fiber mix. This highlights its ability to replace synthetic and inorganic fibers in ECC mixture.