Geotechnical characteristics correlations for fine-grained soils

Compressibility and shear strength are the principal geotechnical engineering properties of soils, which control the stability of a soil mass under structural loads. Therefore, it is always required to be measured before the design of the foundation of any structure. Evaluation of shear strength and compressibility characteristics are time consuming and laborious. Hence, there is a necessity for prediction of those characteristics with the help of correlating them with index properties, initial void ratio, natural moisture content, field densities of soils, which can be determined easily. In this paper, a study is conducted on two sets; two and three geotechnical natural properties together for Barika, Arbat and Hwana fine-grained soils in Sulaimani Governorate, Iraq. In addition, new empirical relationships with single and multiple dependent variables were developed with better estimation capability. The best relationship was observed between plasticity index as a function of liquid limit with correlation coefficient (R) and RMSE equal to 0.874 and 2.18 respectively. Whereas, there was no significant relationship between coefficient of compressibility (compression index, Cc) and consistency properties was noticed.