Robust Geotechnical Design of Piles Incorporating System Reliability

There is a trade-off between pile safety and cost, and a balance between the two factors is crucial. An important aspect of pile safety that is often overlooked is design robustness, which requires that the structural response is not sensitive to the variation of statistics of noise factors. This study proposes a framework for cone/piezocone penetration test-based robust geotechnical design (RGD) of piles that incorporates system reliability. The framework considers the robustness of the system reliability against various sources of uncertainty such as spatial variability, model imperfection, and measurement errors as well as multiobjective optimization of design robustness, safety, and cost. Three ultimate pile capacity (UPC) calculation methods are considered. A MATLAB GUI platform is developed to enhance the practical application of the RGD framework. Two examples are presented to illustrate this framework. The RGD results are less affected by UPC methods, which can avoid the deviation of design results caused by the selection of design methods. The results are also insensitive to variations in the coefficient of variations and distributions of noise factors while being cost-effective and safe.