Effects of type and duration of pigment milling on mechanical and colorimetric properties of colored self compacting mortars (CSCM)

Abstract

The mechanical properties of colored mortars and concretes are almost always susceptible to decrease due to presence of pigments; on this basis it is important to use appropriate colorants. Usually, inorganic pigments are used as consistent colorants for concretes but they create dirty, limited and sometimes pale colors even at high pigment contents. In this research, TiO2 and FeO(OH) pigments were used to produce white and yellow colored self-compacting mortars (C-SCMs), respectively. Dry and wet milling processes at different durations were used to grind the pigments and achieve deeper colors. The effects of pigment milling type and duration on mechanical properties and appearance of SCMs were investigated. Results indicated that pigment fineness significantly influenced SCMs compressive and flexural strengths. Wet-ground pigments presented higher compressive (i.e 10%) and flexural strength (i.e 5%) than dry milled pigments. Both dry and wet milling processes improved saturation (i.e. C*) of the produced colors in SCM samples but neither of them could boost the color intensity (i.e. L*).