Expanding the Use of Fly Ash as an Admixture in Concrete in Vietnam

Abstract

To bolster the drive for economic and social development in Vietnam, 31 coal-fired power plants were constructed to meet the demand for electricity. According to a survey by the Ministry of Natural Resources and Environment, approximately 20.5 million tons of coal ash will be generated in 2020. A part of the generated coal ash was recycled as landfill; however, the rest lies unused or discarded, causing serious environmental pollution. Since fly ash (FA) forms a major component of coal ash, it is necessary to establish methods for the safe, continuous, and effective use of FA. This study compared the Vietnamese National Standards with the Japanese Industrial Standards from the perspective of using FA as an admixture in concrete. Japanese FA was used in the experiments. Consequently, by using suitable amounts of chemical admixtures and adjusting the ratio of FA as a cement replacement and as a fine aggregate replacement, structural concrete can be manufactured, and the required quality can be assured.