Effect of limestone addition on early-age properties of ultra high-performance concrete

In the present study, the effects of using limestone as partial replacement for cement on the early-age properties of ultra high-performance concrete cured at simulated cold and normal field conditions were investigated. Different particle sizes of limestone, ranging from nano (15–40 nm) up to 12 µm, were added at rates of 0, 5, 10 and 15% as partial volume replacement for cement. The results indicate that in very low water/cement ratio concrete mixtures, the incorporated micro-sized limestone acts mainly as an inert filler material, creating a denser microstructure and increasing the effective water/cement ratio. Although the mixtures incorporating micro-sized limestone exhibited mechanical properties that were comparable to or weaker than those of mixtures incorporating nano-sized calcium carbonate, they had similar or higher mechanical properties than those of the control mixture without limestone. Thus, environmentally friendly concrete can be produced using micro-limestone, by reducing the cement factor of ultra high-performance concrete while enhancing the mechanical properties

Effect of limestone addition on early-age properties of ultra high-performance concrete Journal Articles