Análise Probabilística de Aterro sobre Solos Moles

Patrícia Rodrigues Falcão; Diego de Freitas  Fagundes; Antônio Marcos de Lima  Alves

doi:10.14295/vetor.v30i1.12905

Authors

Patrícia Rodrigues Falcão Escola de Engenharia, Universidade Federal do Rio Grande
Diego de Freitas Fagundes Programa de Pós-Graduação em Engenharia Oceânica, Universidade Federal do Rio Grande
Antônio Marcos de Lima Alves Escola de Engenharia, Universidade Federal do Rio Grande

DOI:

https://doi.org/10.14295/vetor.v30i1.12905

Keywords:

Soft soil, Deterministic Methods, Probabilistic Methods, Failure Probability

Abstract

No model correctly predicts a given system's reality, so that the engineering calculations have uncertainties, which may cause several kinds of errors. The constructions on soft clay deposits present a high difficulty due to such soil's high compressibility and low resistance. The geotechnical designs of embankments on soft soils are traditionally analyzed using a global safety factor obtained through deterministic methods, not incorporating the calculation's inherent uncertainties. On the other hand, the probabilistic approach makes it possible to quantify the uncertainties arising from the parameters' variability and the more comprehensive assessment of the expected safety level for the work through the probability of failure. In this way, it is possible to untie the idea that high safety factor values always guarantee safer projects. In this context, this study aims to compare the solutions obtained by the Probabilistic Methods of Rosenblueth, Monte Carlo, Latin Hypercube, and First Order Second Moment (FOSM), in addition to evaluating the results by means of a deterministic approach using the methods of Bishop Simplified, Janbu Simplified, Spencer and Morgenstern & Price. Stability analyses were performed using the Slide v.6 computational tool. The analyses show the importance of introducing the coefficient of variation in the parameters since the uncertainty directly affects the level of performance expected for the work.

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