Caracterização e avaliação das propriedades geomecânicas para uso em pavimentação de agregados de rochas vulcânicas da porção central do Rio Grande do Sul

Abstract

The mineral resources have been widely used by man since its inception, among them are those employed in construction due to the enormous volumes that are demanded of this material and its low cost in relation to other minerals. The need to open roads for the free movement of man and his goods did it start to study the best way to build highways, where vehicles are the most used mode of transportation. At the beginning of those studies, the properties of the constituent materials of the pavement were not take into account due to lack of knowledge about its effect on the strength of the structure. After several researches, researchers concluded that the materials that make up the pavement influence its performance and durability. It is through tests that determine the properties of the materials as well as the knowledge of their origin of formation. This research reports the characterization and evaluation of the geomechanical properties of aggregates commonly used in road paving, collected in units of the central portion of Rio Grande do Sul, through physical and geomechanical tests. Thin slides were used to classify the materials into acidic, intermediate and basic rocks of the type rhyodacites, basaltic andesite, basalt and diabase. This classification allowed predicting the behavior of the aggregates for some of the parameters commonly analyzed in aggregates for road works, such as the physical indices and the adhesiveness where the acid rocks did not obtain satisfactory values for the CAP 50/70. From the studied parameters, the shape was evaluated under different methods from the most usual ones such as the use of the pachymeter and lamellarity plate, to the methods that have been improving this way of analyzing the particles of the aggregates as the use of AIMS software that allowed verifying texture characteristics surface of the particles. Regarding to the evaluation of the strength of the studied material, the crushing, abrasion and shock mass tests with the Treton apparatus performed for this research, obtained satisfactory results, in addition, when compared with each other, it was verified that results show a tendency of the influence of the form in the greater losses of mass. At the end of the study, the relationships between the parameters that presented the best correlation coefficient were analyzed.