Modeling of Spatial Variability of Soil Property and Reliability Based Design of Piles

It is the essence of geotechnical design to obtain soil parameters for design that are different from a site to another. Therefore, soil investigations play very important role in geotechnical design. The modeling of the ground based on investigation results is called site characterization, and there are some new developments in this area based on statistical theories. In the new approach, the results are directly related to reliability based design of geotechnical structures, where the resulting uncertainties (e.g. ultimate bearing capacity of a pile, settlement of embankment etc.) related to soil variability and statistical estimations are quantified. This study covers the following contents: (1) Explain some basic statistical concepts and tools that are necessary to understand the statistical site characterization of ground for geotechnical design. (2) Introduce some statistical site characterization examples and describe the procedures to carry out the analysis. The examples include several sites where CPT tests were carried out extensively. (3) Based on the statistical site characterization, vertical bearing capacity of piles is evaluated to see the influence of soil variability and statistical estimation errors. (4) Summary, conclusions and possible future works will be suggested.