Cost-Effective Mix Design for Ultra-High Strength Concrete Up to 170 MPa

Ultra-high strength concrete (UHSC) have received increasing research attention due to its superior performance. However, many of the existing UHSC mixes may require special curing methods such as heat or pressure. In addition, some mixes contain unusual materials, such as silica sand and ground quartz in order to improve the inner structure of the concrete. Therefore, they seem to be uneconomic due to the high cost of manufacture as well as complexity, which is making UHSC out of reach for most constructions in practice. As a solution for these issues, the present work proposes three concrete mix designs with grades of 130, 150 and 170 MPa. The mixtures are designed for manufacturing cost-cutting and advancing the practicality of UHSC by using normal raw materials (including cement, fly ash, silica fume, natural sand and basalt aggregate) and simple curing condition with ambient temperature. Moreover, the proposed mixes are also compared with existing mixes of recent researches in terms of superplasticizers dosage and the presence of specially graded aggregates to demonstrate their advancement.