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Geopolymers are a class of inorganic synthetic materials that in recent years have received extensive interest of the scientific community, mainly due to the variety of applications in which they can be used. The synthesis of these materials is based on a chemical process called geopolymerization, which consists of the alkaline activation of amorphous alumina and silica oxides present in many natural raw materials and industrial solid waste. Therefore, the present work proposes the use of inorganic mining residues (mine tailings) from gold mining in the southern region of Peru, for the manufacture of geopolymeric concrete. The first part of the research focused on the physical, structural and microstructural characterization of the raw material (fine sand and mining tailings), then the volumetric matrix of mixtures for five types of geopolymer concrete was determined. Cylindrical samples of 20 mm diameter and 40 mm high geopolymeric concrete were manufactured, at the same time conventional Portland cement concrete was manufactured for comparison purposes. All materials were mechanically characterized by uniaxial compression tests at variable temperatures (from room temperature to 600 ºC), and they were also microstructurally characterized before and after mechanical tests. The main microstructural mechanisms responsible for the fracture and plastic deformation of geopolymeric and conventional Portland cement concretes have been determined.

Geopolymeric materials have recently been considered a revolutionary class of materials, due to the diversity of applications where they can be used, this derived from their good mechanical resistance, thermochemical stability and good fire resistance. From 1970 to the present, a notable increase has been observed in the number of scientific publications dealing with the synthesis and applications of geopolymeric materials with industrial application. Several publications have reported geopolymers as alternative materials to Portland cement, which will allow having a green construction industry in the coming years. The elaboration of geopolymeric materials is relatively simple, beginning with the identification of a source rich in amorphous aluminosilicates and a hardening compound (mainly alkaline in nature) which are properly mixed until a homogeneous and workable paste is obtained, then can harden at room temperature and acquire good mechanical resistance in a few hours. On the other hand, mining in Peru is one of the most important industries due to its contribution to the economic development of the country. However, mining is also one of the industries with the greatest negative impact on the environment, mainly due to the enormous amount of inorganic waste that it generates and which is currently accumulated without any prospect of recycling or reuse. Therefore, this research was conducted to elaborate concretes from mining tailings and to evaluate their mechanical behavior in creep (between 500 and 600 ºC). The results obtained allow us to propose the use of mining tailings for the elaboration of geopolymeric thermal barriers that work in conditions of intermediate temperatures, up to 600 ºC.

Geopolymers are a class of inorganic synthetic materials that in recent years have received extensive interest of the scientific community, mainly due to the variety of applications in which they can be used. The synthesis of these materials is based on a chemical process called geopolymerization, which consists of the alkaline activation of amorphous alumina and silica oxides present in many natural raw materials and industrial solid waste. Therefore, the present work proposes the use of inorganic mining residues (mine tailings) from gold mining in the southern region of Peru, for the manufacture of geopolymeric concrete. The first part of the research focused on the physical, structural and microstructural characterization of the raw material (fine sand and mining tailings), then the volumetric matrix of mixtures for five types of geopolymer concrete was determined. Cylindrical samples of 20 mm diameter and 40 mm high geopolymeric concrete were manufactured, at the same time conventional Portland cement concrete was manufactured for comparison purposes. All materials were mechanically characterized by uniaxial compression tests at variable temperatures (from room temperature to 600 ºC), and they were also microstructurally characterized before and after mechanical tests. The main microstructural mechanisms responsible for the fracture and plastic deformation of geopolymeric and conventional Portland cement concretes have been determined.