Estimativa de recalques de sapatas apoiadas em solos arenosos : uma abordagem probabilística

• Autor(a) principal: Bungenstab, Felipe Carvalho
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/3948
• topic: Sandy soils; foundations; settlement of structures; probabilities; Solos arenosos; fundações; recalque de estruturas; probabilidades; Engenharia Civil; Solos arenosos; Fundações (Engenharia); Recalque de estruturas; Confiabilidade (Engenharia); Probabilidades; 624

This research discuss about probabilistic settlement analysis of footings in sands, focusing on the load curve (estimated settlements). For this purpose, three methodologies that take the First Order Second Moment (FOSM), Second Order Second Moment (SOSM) and Monte Carlo Simulation (MCS) methods for calculating mean and variance of the estimated settlements using the equation proposed by Schmertmann (1970) are discussed. The resistance variability curve (limit settlements) is assumed to be constant for some specific values. The deformability modulus (ESi) is considered varying according to the division of the soil into sub-layers and it is analyzed as the only independent random variable in process. As an example of the application of these methodologies, an unreal simplified case work in state of Espirito Santo, Brazil, on the use of compaction piles of sand and gravel, driven by Franki-type equipment, for densifying marine sandy soil, is discussed and evaluated. Results of the simulations indicate that there is significant similarity between SOSM and MCS methods and that the FOSM method underestimates the results due to the non-consideration of the high orders terms in Taylor expansion series. It has been also observed that the depth which the major variance contribution occurs is dependent of the ESi values in the layer analyzed, with strong influence of the IZ distribution factor, from Schmertmann (1970). The proposed probabilistic analyses may contribute to the knowing of the uncertainty in settlement estimations that can lead to more safety geotechnical design.