Análise do uso de resíduos da construção civil como substituinte parcial do aglomerante em argamassa de revestimento.

Abstract

Civil construction plays a very important role for the economic and social development of the country. However, it is responsible for the extraction of natural resources from non-renewable sources for the production of building materials and for the high generation of waste from losses during the construction process. In order to reduce the environmental impacts generated by civil construction in recent years, there has been growing concern about the final disposal of waste generated by the sector. The incorporation of them as raw material for the production of mortars is an alternative for minimizing impacts on the environment. Thus, this research aimed to evaluate the potentiality of the use of the predominantly cementitious fraction of two civil construction residues (CMR) as a partial substitute for cement in coating mortars, considering their physical and mechanical performance. The waste was collected in two different locations in the city of Pelotas/RS, the first coming from the demolition of an industrial building in the central region (RCD), and the second, coming from a cementitious artifacts factory (RIPM) located in the northern part of the city. For the experiment, the reference trait was in the proportions of 1:2:8 (cement, lime and sand) and the substitutions of cement by residue were performed at the levels of 5, 10 and 15%. Mortars were evaluated for mechanical performance (axial compressive strength, tensile strength in diametric compression, tensile strength in flexion) and physical (water absorption by capillarity, immersion absorption and void indices). The statistical analysis demonstrated the feasibility of replacing the cement by ripm with replacement levels of up to 15%, since they provide the manufacture of sustainable coating mortars, with mechanical and physical performance equivalent to the reference trait at the age of 28 days. In the RCD, the content of 5% presented mechanical resistance proportional to the reference trait at 28 days and the other traits required a longer period to achieve the same performance of the ref trait. In relation to the physical parameters the best performance was recorded by the content of 10% of the RCD.