Property Correlations and Statistical Variations in the Geotechnical Properties of (CH) Clay Soils

This study was focused on the correlations between the physical and mechanical properties and geostatistical analysis of the clay of high plasticity (CH) soil based on the experimental data and the data collected from various research studies. Four types of CH soil with liquid limit (LL) of 50, 62, 76 and 88% were collected from the field, tested, compared with the data from literature and qualified using hyperbolic model. X-ray diffraction analyses showed the major constituents of the CH soil with LL of 50% were calcium silicate (Ca₂SiO₄), aluminum silicate (Al₂SiO₅) and quartz (SiO₂) and the major constituents of the CH soil with LL of 88% were montmorillonite (Na, Ca) _0.33(Al, Mg) ₂(Si₄O₁₀) (OH)₂·nH₂O, kaolinite (Al₂Si₂O₅(OH)₄) and quartz (SiO₂). The index properties, compacted properties, free swelling and compressive strength of the CH soils were investigated and quantified with over 1000 data collected from the literature. Using the mean (μ), standard deviation (σ), variation (σ²) and coefficient of variation parameters of CH soils properties such as density (γ), index properties (LL and PL), compaction properties (OMC and γ_dmax), swelling index (FS), initial void ratio (e_o), compression index (Cc) and undrained shear strength (S_u) properties were also studied. Liquid limit of CH soils varied between 50 and 110% and plasticity index varied between 26 and 72%. The wet unit weight (γ_wet) for the CH soils varied from 1.30 to 2.19 g/cm³. Undrained shear strength (S_u) of CH soils were varied from 10 to 184 kPa and quantified very well as a function of liquid limit, plasticity index, moisture content and dry density using the experimental data and data collected from the literature.