A case study on optimizing the geotechnical site investigation using Kriging method

Abstract

One of the major tasks in geotechnical investigation is the stratigraphy distribution and the physico-mechanical properties of strata encountered in the investigation area. In order to reduce the project risks associated with uncertainties in predicting the distribution of strata (in area and in depth), a geotechnical investigation plan is usually designed with as many as possible of the boreholes. And this, in turn, increases the investigation costs. On the contrary, the owner of the project is expected to gather as much information about the subsurface soils as possible at the lowest cost. To deal with this contradiction, geotechnical engineers not only mobilize their knowledge on the investigation area and their experiences in the field of geotechnical investigation but also should be supported by geostatistical tools, especially the interpolation method of Kriging. Based on the real data taken from a geotechnical investigation project in Saigon (Vietnam), this paper will introduce two geotechnical investigation plans: a) an actual investigation plan; b) an optimized investigation plan designed with the support of Kriging method. From these two plans, the ability of Kriging in optimization of geotechnical investigation will be evaluated.