Robust Geotechnical Design of Drilled Shafts in Sand: New Design Perspective

This paper presents a new geotechnical design concept called robust geotechnical design (RGD). This new design methodology, seeking to achieve a certain level of design robustness in addition to meeting safety and cost requirements, is complementary to traditional design methods. Here a design is considered robust if the variation in the system response is insensitive to the variation in noise factors (mainly uncertain soil parameters). To aid in selection of the best design, a Pareto front that describes a tradeoff relationship between cost and robustness at a given safety level can be established using the RGD methodology. The new design methodology is illustrated with an example of drilled-shaft design for axial compression. The significance of the RGD methodology is demonstrated.