Estudo das condições geotécnicas de estradas rurais do município de Alegrete/RS

Abstract

This paper presents the study of utility and analysis of the geotechnical conditions applied to the primary coating layers of 4 unpaved rural roads, inserted in the municipality of Alegrete / RS. For this, initially a bibliographic research was carried out aiming to guide and to establish the methodology of the work. As part of the field activities was applied the Unpaved Highway Conservation Index (ICRNP), which allowed to evaluate the pathologies of the studied roads, quantifying and recording the appearance of the main defects that affect the trafficability of motor vehicles. After that, in the primary coating layers, the control of the apparent specific mass by the sand bottle method, the in-situ verification of their respective thicknesses and the collection of deformed soil samples were performed. In the laboratory, the collected samples were submitted to geotechnical characterization tests, compaction, expansion and California Bearing Ratio (CBR) tests. Using the results of experimental field and laboratory tests, three methods of sizing primary coating layers were applied. The roads studied were classified by the ICRNP as very poor, thus concluding that the lack of a good drainage system and proper cross section can cause serious durability problems and greater need for maintenance. In general, for the studied roads, the sizing methods showed that the primary coating layers have thicknesses below the suggested values. Finally, the study showed the need to use techniques that allow proper maintenance and sizing that can be applied to rural roads in the municipality of Alegrete / RS.