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This work presents the results of the thermomechanical evaluation of geopolymeric concrete fabricated from mining tailings, rice husk ash and fine sand. Ten types of geopolymeric concrete were studied and the relationship between the initial volumetric concentrations of the components in the mixtures and the maximum resistance in uniaxial compression under conditions of variable temperature (between ambient and 600 °C) was analyzed. The results revealed that increases in the concentration of mining tailings and fine sand lead to an increase in the value of the maximum mechanical resistance, in contrast, the increase in the concentration of rice husk ash led to a reduction in the value of the maximum mechanical resistance. Furthermore, increases in test temperature, up to 500 °C, led to systematic increases in maximum mechanical strength. Finally, the geopolymeric concretes presented a brittle-ductile transition between 500 and 600 °C showing only a ductile behavior when tested at 600 °C and only brittle up to test temperatures of 500 °C.

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Reinforced geopolymeric mortars were obtained by mixing mine tailing, fine sand, alpaca wool fibers ( in variable amounts) sodium hydroxide and potable water, it was possible to verify the effect of the addition of alpaca wool on the mechanical behavior in uniaxial compression of the mortars studied. The mechanical data found revealed a systematic decrease in the maximum stress as the volume of wool added in the mortar mixtures manufactured increased. On the other hand, a higher degree of deformation was verified in mixtures with a greater volume of added fibers, reaching deformation values of up to 5%. The maximum strength values were in the range of 4 to 21 MPa for samples with 8 and 0 Vol. % of added fibers, respectively. Among the microstructural characteristics of the mortars studied, a continuous binder phase corresponding to the geopolymer could be appreciated, with sand particles and wool fibers dispersed within the binder phase. The real density and average porosity of the reinforced mortars were 2.65 g/cm3 and 32%, respectively.

Geopolymeric mortars with volumetric fractions of 0.6:1:0.3 for a binder powder, fine sand and sodium hydroxide solution (12M), respectively; have been fabricated by mixing the solid materials and the subsequent addition of sodium hydroxide solution 12M to form a workable paste, to later be cured for 28 days at room temperature. The microstructures of the fabricated materials reveal the existence of two phases with notable difference, one continuous to the geopolymer binder phase and another discontinuous of fine sand particles agglutinated by the binder phase. Mechanical compression tests are performed at a constant compression rate of 0.05 mm/min and at temperatures ranged from room temperature to 500°C. The mechanical results are ranged from 19 and 69 MPa for all the materials studied. On the other hand, there was an increase in mechanical resistance up to test temperatures of 200°C and the progressive reduction of resistance at temperatures above 200°C, with a fragile-ductile transition zone between 400 and 500°C and completely ductile behavior from test temperatures of 500°C., 0 0 (201 MATEC Web of Conferences https://doi.org/10.