Contribuição para a caracterização do subsolo do município de Toledo-PR para fins de geotecnia

Abstract

Studying the soil is a paramount part of a civil engineering project because it can influence the costs of foundations, as well as on their safety. Therefore, the Brazilian standards that deal with soil characterization were used to perform tests whose objective was to understand and classify the type of soil existing in the urban area of the Toledo-PR. Thus, through the trials and together with the analysis of other studies found in the literature, it was possible to identify this soil. It is a soil of the Latosol type, which has the highest incidence rate of the state of Paraná, being clayey, with fine contents higher than 70%, silt ranging from 10 to 20% and other granulometry in small proportions. The samples analyzed in the laboratory presented an average of 2.679 g/cm³ for the specific mass of the grains, with a standard deviation of 0.168 and ranging between 2.435 and 2.892 g/cm³. It is also a soil with liquidity limits between 52 and 61% for shallow soils and with significant dispersion for plasticity limits, from 28 to 51%, influencing the classification in relation to plasticity, however, in general all presented good workability and plasticity rates ranging from medium to high. In addition, a significant difference was observed between the samples of depth 14 and 15 meters. They were acquired from an SPT sampler in small quantities, approximately 500 g for each, and for this reason, for the Atterberg limits tests, the material of the specific mass of the grains was reused through kiln drying, which may have influenced the particles cohesion and consequently the results tests. Furthermore, the possible presence of organic matter was noted in the sample of 15 meters deep, which presented the lowest clay contents in the soil, 69.16%, the lowest specific mass, of 2.435 g/cm³ and also high values for the plasticity limit in relation to the liquidity limit, 86 and 100% respectively, consequently reducing the plasticity index to 14% and the soil classification for consistency and plasticity.