Análise da influência do pH da água, grau, umidade e forma de compactação no coeficiente de permeabilidade de um solo do município de Alegrete-RS

Abstract

The soil permeability is of great importance for various types of geotechnical engineering constructions, the earth dam is one of this construction that is most dependent on this parameter. In the west region of the state of Rio Grande do Sul, dams are found in abundance due to this region’s high dependence on agriculture, which demands a lot of water. In order to contribute to the construction of safer dams, this research aims to evaluate the influence of water pH, degree, water content and compaction method in a clayey-sand soil of the city of Alegrete-RS permeability. This soil was submitted to permeability tests, through rigid wall permeameters compactionmold type. A total number of 24 specimens, and under a range of water contents, compacted by dynamic and static method, were subjected to permeability test. Also, permeability tests are being performed by percolating water with three different fertilizers, the limestone, the urea, and the triple superphosphate, to evaluate the influence of water pH on permeability. In this search it was possible to verify the permeability change with the addition of compaction’s water content, where smaller permeability values were found for optimum to greater values of water content. Also, it was possible to observe differences in the permeability behavior between the two compaction methods. The permeability behavior verified, can be explained by the differences in the soil structure generated in clay soils by the different compaction method and water content. This can be observed by comparing samples with identical void ratios, but with different dry unit weight, and samples with identical void ratios and water content, but compacted through different methodologies, which presented distinct permeability coefficients. With the results obtained, simulations of dam models were performed. Where it was observed the possibility of using other water content settings, besides the optimum water content, with a good performance in relation to the flow.