Two-Dimensional Random Field of Mechanical Soil Properties

In situ tests were performed and samples were taken from a uniform layer of clay used as a material for the production of bricks. The shear resistance was measured, using Geonor Inspection Vane Tester H-60, in a quadratic mesh of 961 test points in the horizontal plane, spaced at 15 cm. Vane resistance tests were also performed in the laboratory on 76 undisturbed samples, on which the constrained modulus in consolidometers was determined. The aim of the research was to find the parameters of the 2D random field of shear strength and the correlation of this field with that of constrained modulus. The strong correlation obtained eventually enabled estimating the autocorrelation function of the constrained modulus describing the elastic behavior of the soil. A simple estimation procedure is proposed, enabling curve fitting of different isotropic and anisotropic correlation functions. Additionally, some statistical analyses of data were performed, including regression and time series analysis. The problem of the local and global variabilities of soil properties and their ramifications is also considered.