Ultra-high-performance concrete with local high unburned carbon fly ash

Ultra-high-performance concrete (UHPC) is a kind of high-tech cementitious material with superb mechanical and durability properties compared to other types concrete. However, due the high content cement silica fume used, cost environmental impact UHPC considerably higher than conventional For this reason, several efforts around world have been made develop greener less expensive local pozzolans. This study aimed design produce using fly ash available in Colombia. A numerical optimization, based on Design Experiments (DoE) multi-objective criteria, was performed obtain mixture proper flow highest compressive strength, while simultaneously having minimum cement. The results showed that, despite low quality ashes Colombia, strength values 150 MPa without any heat treatment can be achieved.