Spatial Interpolation of Geotechnical Properties Using EBK, IDW, and Kriging: A Case Study in Astana, Kazakhstan

This paper investigates the performance of interpolation methods for defining intermediate geotechnical soil properties, such as Empirical Bayesian Kriging (EBK), Inverse Distance Weighting (IDW), and ordinary Kriging. The interpolation results were visualized in the form of heatmaps, which allowed for the evaluation of the spatial variability of soil characteristics. The differences between the obtained values were also quantitatively analysed utilizing histograms. Borehole data from a construction site in Astana were processed in ArcGIS Pro using EBK, IDW, and Kriging methods to interpolate cohesion, friction angle, and deformation modulus between observation points. Results showed differences in value ranges and distribution patterns, with EBK providing smoother and more stable estimates in sparsely sampled transition zones, while also acknowledging the dependence on data density and interpolation assumptions.