Uso dos elementos finitos e discretos na modelagem do comportamento drenado de uma areia aluvionar: um estudo comparativo.

Abstract

For stress-strain analysis of geotechnical problems, several software programs are usually used, with their various constitutive models, most of them based on the finite element method (FEM), considering the soil as a continuous medium. However, it is known that soils are formed by particles and when a stress is applied, this stress is transmitted particle by particle and consequently, when subjected to external loads, they present a complex behavior, which can be better visualized at the micro scale. Thus, the use of the discrete element method (DEM) can be an alternative to predict soil behavior in a broader and more realistic way. However, because it is a relatively new method, its implementation and performance evaluation should be compared to classical methods, which are already well established and present adequate results. Knowing this, the present work aims to determine the drained behavior of an alluvial sand, through experimental studies and numerical simulation of triaxial tests. The numerical modeling was done employing the finite element method, using the software Sigma/W and OPTUM G2 and through the discrete elements, in the C programming language. Through the results obtained, a comparative analysis was performed and a discussion of the advantages and limitations of each method in representing the behavior of soils when subjected to triaxial tests. In general, it was found that the samples tested through the numerical methods presented results similar to those observed in the laboratory, within their limitations. In the case of DEM, there is the high computational cost and for FEM, the constitutive models available in the commercial programs used.