The use of inorganic pigments in the production of colored geopolymer concrete.

The feasibility of coloring geopolymer concrete that uses slag as a binder was investigated in this work by employing inorganic pigments and examining the influence of the pigment on certain geopolymer concrete parameters. In geopolymer concrete, tests were carried out with the addition of two pigment types (cobalt blue and iron oxide red), at percent of 0, 2, 4, 6 and 0, 1, 2, 3 %, respectively, of the slag's weight. Values of slump, compressive strength, flexural strength, indirect tensile (splitting) test, permeability test and Fourier transform infrared spectroscopy (FTIR) test were obtained. It was found through the above tests that the optimum percentage of adding pigments is 1% for the red pigment and 2% for the blue pigment. It was concluded through the FTIR test that both pigments that were used in this research did not interact with the other components of the mixtures and did not affect the interaction of the components among themselves. [ABSTRACT FROM AUTHOR]