Assessment of Uncertainties in Soil Parameters Using Finite Element Coupling Technique

Abstract

Uncertainties are unavoidable in geotechnical engineering design. Quantifying uncertainties and the related risks are very important in the overall design. For problems involving complex soil-structure interactions, using a fixed partial or global safety factor may lead to unrealistic failure or conservative design. The probabilistic analysis could be used as a basis for handling various types of uncertainties. The reliability analysis for complex structures requires a coupling between two models. A finite element model (FEM) to evaluate the limit state function (LSF) and a reliability model to deal with the random variables and reliability methods. Since the coupling between FEM and reliability methods is considered a new field, there is a need to use a hybrid technique for coupling. In the present paper, a developed technique for coupling between PLAXIS 2D v20 and Probabilistic tool-kit (PTK) is illustrated and checked throughout verification examples. The main goal is to present an “easy to use” reliability analysis technique to identify the probability of failure, the reliability index, and the influence factors for complex geotechnical structures. The results show that the developed coupling technique has a good reliability analysis result compared with the previous studies and it can be used to optimize the current design procedure for geotechnical structures.

Keywords

• reliability analysis
• form
• uncertainty