Santos Júnior, Olavo Francisco dosAraújo, Plenyo Nahen Gonzaga2022-11-172022-11-172022-08-31ARAÚJO, Plenyo Nahen Gonzaga. Modelo constitutivo NorSand aplicado à areia de duna de Natal. Orientador: Olavo Francisco dos Santos Júnior. 2022. 99f. Dissertação (Mestrado em Engenharia Civil) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2022.https://repositorio.ufrn.br/handle/123456789/49790The study of soil behavior is essential for successful disaster prevention and mitigation, as mass movements may occur in catastrophic proportions, leading to many failures, deaths, and significant financial losses. A flow slide occurred in Natal, Brazil, and raised the demand for evaluating the Natal dune sand's behavior regarding the susceptibility to static liquefaction. For this purpose, a numerical investigation was performed through a constitutive modeling approach. The present work aims to evaluate the performance of the NorSand model by assessing the Natal dune sand behavior under different conditions of drainage and state. NorSand is a model based on Critical State Soil Mechanics, using the state parameter as a reference for the model properties. The model parameters were obtained by 16 triaxial compression tests, varying pressure, state, and drainage conditions. The validation of the model was accomplished by comparison between laboratory tests and numerical simulations. A parametric analysis of undrained tests was carried out in order to fit the numerical curves to this drainage condition. The void ratio of loose sands was also varied. In addition, triaxial tests were simulated on samples subjected to intermediate stresses. Moreover, numerical simulations with confining pressure p´ = 100 kPa in contractive samples were confronted with the MohrCoulomb response. The model calibration showed a satisfactory response in comparison to the real lab tests. The parametric analysis evaluated the influence of some model properties in undrained conditions. The stress-dilatancy and hardening properties indicated a large influence on curves. The void ratio variation on loose samples showed the development of static liquefaction until the soil presented total strength loss. Simulations with intermediate stresses showed the expected behavior to these stress conditions, and confirmed the validation of the model. In addition, the comparison between NorSand and Mohr-Coulomb models presented the sophistication of an elastoplastic model regarding simpler theories when submitted to the same conditions. In drained conditions, the stress-strain curve indicates a similar ending behavior between both models, but the similarities are restrained to this curve. In undrained conditions, the Morh-Coulomb model shows unrealistic outcomes regarding static liquefaction.Acesso AbertoEngenharia civilModelo NorsandAreiaModelo elastoplásticoEstado críticomasterThesisCNPQ::ENGENHARIAS::ENGENHARIA CIVIL