Influência do teor de cinza volante na reologia de argamassa de assentamento: fabricado com reciclagem de resíduos

Abstract

The mortars may be considered as a set of solid suspended particles (aggregate), water and binders (cement slurry). Thus, rheological behavior during cure can be influenced by factors such as particle size, composition and content of corporate water. This study investigated the rheological properties of six mortars, depending on the content of fly ash as a pozzolanic activity material, partial replacement of cement. This type of cement used as an aggregate base construction of the residue (RCC) which was characterized by diffraction and fluorescence X- rays. Were formulated for the mortars with addition of rheological tests residue construction (RCC) in proportions of 95, 90, 85, 80, 75 and 70% fly ash (CV) 0, 5, 10, 15, 20 and 25 % to 5 % of ordinary Portland Cement (PC - II and 32), and in each sample was incorporated 35 % water. We used the model VT 550 viscometer with sensor type coaxial cylinders SV1 - Haake temperature of 28 ºC. To evaluate the curing time of the material has scheduled a constant shear rate 53.4 s-1 for 1h and 45 min, with rated torque at intervals of 15min. For the development of flow curves and hysteresis curves, we used the shear rate between 0 and 600 s-1 in the time interval of 120 s. The results showed that the incorporation of fly ash is the main factor for increased torque on the curing time of mortar and behavior change reópetico for thixotropic, the traits analyzed. The experimental data of the proposed formulations are adjusted to the rheological model of Herschel - Bulkley.