Optimization of Geotechnical parameters using Taguchi’s design of experiment (DOE), RSM and desirability function

The use of finite element analyses in the design of geotechnical problems is mainly related to the choice of mechanical characteristics (parameters) of soil. Therefore, the optimization of these parameters is considered as the most important step in geotechnics. The main objective of this work is to identify the mechanical parameters based on Mohr–Coulomb model, by conducting pressuremeter tests on synthetic clayey soil, using Taguchi’s experimental design method. The Taguchi L16 orthogonal array is widely adopted as a modeling support for the simulation of the pressuremeter test, using the finite element software Plaxis. Then, a statistical treatment of the obtained results is carried out based on the concept of the analysis of variance and the development of a mathematical model based on the response surface methodology, in order to identify the significant factors of the model and their interactions. Finally, the optimal values of factors might be chosen using result analysis of Taguchi’s experimental design method, combined with the desirability function approach. This study has shown that the proposed approach is an efficient and effective tool for the identification of soil parameters.