Feasibility Using Electric Arc Furnace Dust as Cementing Material in High Performance Concrete

摘要

High performance concrete (HPC) is a specialized type of concrete that has been designed to be more durable and stronger than conventional concrete, thus became popular due to its superior mechanical and durability properties. Use of supplementary cementing materials such as fly ash, silica fume, and EAFD is often mandatory in the production of high-strength concrete. The effect of EAFD on the fresh and hardened properties of high performance mortar (HPM) mixtures prepared using different water-to-cementious materials (w/cm) ratios were investigated. A comparative study between EAFD and two well-known supplementary cementitious materials at different replacement levels of 0, 5, 10, 15 and 20% at w/cm ratios of 0.4 and 0.3 was carried out. The results showed that the setting times of mixtures incorporating up to 20 % EAFD were in the normal range and similar to those of controls, SF and FA mixtures. At any w/cm ratio, the EAFD can be used up to 15% replacement level and at this replacement level, the compressive strength is between the FA and SF contents. Furthermore, the 20% EAFD give lower electric charge values than the control mixture, and it is better than FA mixtures. Tests on selected high-performance concrete (HPC) mixes confirmed the results from HPM mixtures. Use of 10% EAFD as a cement replacement in HPC show there are similar setting times to HPC mixes with 10% SF and 20% FA. The compressive strength of EAFD mix was slightly lower than those of SF and FA mixes but exceeded that of controls.