Modified, Reliability-Based Robust Geotechnical Design Method, in Accordance with Eurocode 7

In this paper a modification of the reliability-based robust geotechnical design (RGD) method is proposed. The intention of the proposed modifications is to simplify the method, make it less computationally expensive, and harmonise of the results with Eurocode 7. The complexity of the RGD method mainly stems from the calculation of the design's robustness measure, which is the feasibility robustness index (beta(beta)). Due to this fact, the replacing of the existing robustness measure with a generalised reliability index (beta) is considered. It was demonstrated that beta fits into the robustness concept, and is traditionally used as a construction reliability measure, making it intuitive and user friendly. It is proposed to conduct a sensitivity analysis using Soboli indices, with the aim of freezing the variables whose contribution to the system response variance is negligible, which will further simplify the method. By changing the robustness measure, the number of the required reliability analyses is significantly decreased. Further reduction is achieved by conducting analyses only for the designs chosen in the scope of the genetic algorithm. The original RGD method is used as an extension of traditional reliability-based design. By applying the proposed modifications, the RGD method can be used as an alternative to the classic and reliability-based design method.

Automated summary

This paper proposes modifications to the reliability-based robust geotechnical design method in order to simplify the approach, reduce computational costs, and align the results with Eurocode 7. By replacing the existing robustness measure with a generalised reliability index and conducting sensitivity analyses using Soboli indices, the required number of reliability analyses can be significantly decreased. Additionally, conducting analyses only for selected designs within the scope of the genetic algorithm further reduces computational burden.