Tensile properties of slag-based engineered cementitious composites with ground granulated blast-furnace slag

During the last decade, concrete technology has been undergoing rapid development, resulting in a new concept of engineered cementitious composite (ECC) to overcome the brittle behaviour of cement-based materials. ECC is one movement to fully incorporate waste material as an innovation in green material due to excellent toughness and energy absorption capacity, self-healing ability, fire performance, and remain durable under erosion environment. ECC exhibits a strain-hardening behaviour through the formation of micro cracking. This study is focusing on the tensile behaviour of the slag-based ECC. A total of five ECC mixes were designed with different cement to ground granulated blast-furnace slag (GGBS) ratio. Five samples of dog bone and three cylindrical for each mixture were prepared for direct tensile and compression tests. Compared to control samples, there are increments in compressive strength for samples contained 50-60% of GGBS and reductions in compressive strength for samples contained 70-80% of GGBS. The tensile strengths of ECC increase in the rate proportionally to the content of GGBS in ECC mixtures. The failure modes of the ECC cylinder samples including crushing under compressive load and few micro cracks are observed in ECC dog bones.