Characteristics of controlled low-strength materials incorporating cement kiln dust

Abstract

This paper presents a study that focuses on evaluating the feasibility of incorporating cement kiln dust (CKD) in the development of controlled low-strength materials (CLSM). A preliminary study (phase I) was conducted (based on fresh and strength properties) to understand the behaviour of 12 selected CLSM mixtures where CKD and cement content varied from 4% to 45% and from 2% to 4% of total mass, respectively. Subsequently, four best CLSM mixes were selected for a detailed study (phase II), which investigated fresh and hardened properties, addressed durability issues, and made recommendations for suitable mix designs for field applications. The research suggests that CLSM with acceptable properties can be developed using moderate volumes of CKD (up to 15% by mass). A combination of 2% cement and 10% CKD or 15% CKD and no cement can provide a mix that satisfies the requirements of a CLSM. Sustainable development in the cement industry can be partly achieved by producing CKD-based CLSM, as it consumes cogenerated products from the cement manufacturing process.Key words: cement kiln dust, controlled low-strength material, mix design, fresh–mechanical properties, durability.