Study of the spatial variability of soil properties using interpolation methods

Reliable geotechnical modeling is essential for safe foundation design, especially under sparse borehole data conditions common in urban construction. This study compares three spatial interpolation methods - Inverse Distance Weighting (IDW), ordinary Kriging, and Empirical Bayesian Kriging (EBK 3D) - for predicting key soil parameters (cohesion c, friction angle φ, and deformation modulus E) at a site in Astana, Kazakhstan. EBK 3D demonstrated superior performance in terms of spatial consistency and statistical stability. Specifically, EBK 3D yielded the lowest coefficients of variation: 0.167% for cohesion, 0.004% for friction angle, and 0.019% for deformation modulus. These results confirm EBK 3D’s suitability for accurate soil property estimation in data-limited and geologically complex environments.