A study on the deformability behavior of clayey lateritic soils through statistical and correlational analysis

This study investigated the mechanical behavior of tropical soils, specifically lateritic clays (LG’) compacted under intermediate energy, with a focus on the analysis on resilient modulus (RM) and permanent deformation (PD). A database was compiled including 20 Brazilian soils, comprising physical properties (maximum dry density, optimum moisture content, particle size distribution, and MCT classification indices) and mechanical properties data from repeated load triaxial tests. RM and PD regression parameters were evaluated for different stress states, adhering to Brazilian regulations. RM results showed high variability (mean: 351 MPa; CV: 42%), demonstrating a strong influence of deviatoric stress, which significantly reduced the elastic response with increasing stress levels. PD followed a log-normal distribution (mean: 0.635%; CV: 141%), with greater deformation correlating to elevated stress states. Pearson’s correlation revealed associations between RM and physical properties: positive with sand content and negative with clay content and optimum moisture content. Kruskal–Wallis tests confirmed RM’s significant dependence on geotechnical variables, whereas PD showed no statistically significant with these factors. These findings underscore the importance of integrated physical–mechanical characterization for predicting the structural performance of LG’ soils. Furthermore, they highlight PD’s high variability and the necessity for global analyses to achieve more representative estimates in mechanistic–empirical pavement design.