Estudio de morteros adicionados con Dióxido de Titanio frente al ataque de sulfatos

Abstract

An investigation is presented with the purpose of evaluating the behavior of mortars added with titanium dioxide against the attack of chemical agents and in this particular case that generated by sodium sulfate. The preparation of mortar mixtures added with TiO2 in the rutile phase was carried out, in percentages of 0%, 2%, 3%, 4%, 5% and 6% with relation to the weight of cement. The components of the mortar were characterized, in addition, properties such as fluidity, compression resistance, change in length and expansion, absorption rate, unit mass, porosity, variation in volume and weight, determination of pH and study by means of a microscope were evaluated. electronic sweep. The addition of titanium dioxide increased the fluidity of the mixtures by up to 16%. Additions in percentages less than 5% met the design compressive strength, however, it was not superior to the mixture without addition. Under conditions of chemical aggression, the mixture with the addition of 2% recorded the smallest decrease in resistance. For the addition of By 2%, the secondary absorption rate and porosity were decreased and there was less variation in volume and weight. All test specimens were highly affected after 13 weeks of sulfate exposure. The SEM exploration allowed us to observe the formation of ettringite, gypsum and thaumasite products without evidencing a significant contribution of titanium dioxide to the sulfate attack.