Avaliação de diferentes metodologias para reconstrução da curva de compressão oedométrica

• Autor(a) principal: Amaya, Leidi Viviana Pérez
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/11640
• topic: Engenharia civil; Solos argilosos, Compactação dos solos; Soft Clay; Curve; Oedometric Compression; Recreation; Engenharia civil; Solos argilosos, Compactação dos solos; Argila mole; curva; compressão oedométrica; reconstrução; CNPQ::ENGENHARIAS::ENGENHARIA CIVIL

The oedometric compression curve obtained from a soft clay test specimen with moderate sensitivity and plasticity, usually presents some specific characteristics that allows to use it to determine some parameters, such the compressibility rates, which are used to estimate the settlements induced by a given request. However, it is not always possible to identify these characteristics in every soft clays, especially when there is a considerable variation in the curve when the samples or even the same specimens present some degree of remolding. It is known that in soft clay soils it is very difficult to control the effects of the remolding and the disturbance of the samples, thus studies have been developed to take advantage of the results obtained from laboratory tests for the recreating the oedometric compression curve. From the studies already performed, it is known that the curve subjected to the effects of remolding and the curve considered intact tend to join in a range of values of the void ratio, and also that the decompression range does not present considerable changes when the disturbed sample is remolded. Based on these evidences and considering an equation that represents the behavior in an intact compression curve, it was analyzed the applicability of several methodologies for recreating the oedometric compression curve. In order to apply the equation that represents the intact compression range, it is necessary to have two or more stress points that guarantee the interception of the two curves, thus making it possible to solve the system of equations that arise. The present dissertation aims to present several cases recreating the oedometric compression curve, taking advantage of previously mentioned considerations, based on a mathematical development. For this purpose, considering that the intact and deformed curves are joint in the intercept, at this point the derivative that would be the same for both curves. Then, equalizing both expressions generates a new equation, which requires only two stress points. It is also considered a new proposal for estimating the preconsolidation pressure to obtain another stress point to perform the adjustment between the remolded and intact curves. Thus, considering that the recompression section is considered parallel to the decompression section, the oedomometric compression curve is recreated. In the present work, we evaluate the proposal considering the results from several laboratory tests on different soft clay deposits in Brazil.