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Geopolymeric mortars derived from residues of the Peruvian formal mining industry were manufactured and mechanically evaluated under normal conditions of temperature and atmosphere. The mechanical results found in geopolymeric mortars were compared with those found in conventional Portland cement mortars (control). The values of maximum uniaxial compressive strengths for geopolymeric mortars were between 15.5 and 31.5 MPa, finding the best results when considering a ratio binder:fine sand of 1:2, hardener solution molarity of 20M and a ratio hardener solution:binder of 0.6. The microstructure found for both types of mortars studied (control and geopolymeric) consisted of an interconnected continuous phase of binder (cement or geopolymerized mining tailings) and another discontinuous one of fine sand particles, located within the binder phase.

Reinforced Portland cement mortars were manufactured using a mixture of type I cement, fine sand, Ichu (in variable percentages) and water, it was possible to verify the influence of the addition of Ichu fibers on the mechanical response in uniaxial compression of the mortars studied. The mechanical results found revealed a systematic reduction of the maximum mechanical resistance by increasing the volume of Ichu fibers added in the studied mortar mixtures, on the other hand, a greater degree of deformation was evidenced in mortar mixtures with a greater quantity of Ichu fibers added, reaching deformation values of up to 10%. The maximum resistance values found were 0.4 to 3.6 MPa for samples with 16 and 4 Vol.% Of Ichu added, respectively. The microstructure of the mortars studied consisted of a continuous cement binder phase with sand particles and short Ichu fibers dispersed within the binder phase. The real density and average porosity of the mortars reinforced with Ichu was 2.59 g / cm3 and 41%, respectively.

Geopolymeric mortars were prepared from a mixture of calcined clay powders (from demolition bricks), demolition mortar and a 12 molar alkaline hardening solution of sodium hydroxide. The geopolymeric mortars were compared physically, microstructurally and mechanically with their Portland cement counterparts. The results revealed similar densities between both types of mortars (geopolymeric and ordinary Portland cement). The microstructure was also similar in both mortars, two phases can be clearly identified, the continuous binder phase and the phase of individual fine sand particles dispersed within the continuous cement phase. Regarding the mechanical data, it could be verified that the mixture with 80 Vol.% of fine sand, 10 Vol.% of calcined clay and 10 Vol.% of demolition mortar was the one that showed the best mechanical results, with an average mechanical resistance of 34.5 MPa. However, the highest average mechanical strength value for geopolymeric mortars is below the average mechanical strength value of ordinary Portland cement mortar (50 MPa).