Effects of paste thickness on coated aggregates on properties of concrete

The effect of paste thickness on coated aggregates on properties of concrete and the feasibility of using Fuller densified mixture design algorithm to design mixtures of concretes were investigated. There are 9 concrete mixtures with 3 various water-binder ratio (m_w/m_b=0.28, 0.32, 0.40) and 3 various paste thickness on coated aggregates (t=10, 20, 30 μm) designed by Fuller densified mixture design algorithm. Test results show that the new algorithm is on the basis of the aggregate skeleton designed by Fuller's curve and the paste amount estimated by the surface area of aggregate can be adopted to design traditional concrete, even self-consolidating concrete with high workability. The thicker the paste on coated aggregates, the more the paste amount. Although the concrete with thicker paste on coated aggregates has higher compressive strength at early age, after 56 days the concrete with thinner paste on coated aggregates will have higher compressive strength and better durability.