Effect of Moisture Content and Scale on Fine-Grained Soil Compressibility

The majority of engineering problems is based on the analysis of soil properties determined from compression tests, from which the soil behaviour is mainly affected by the change in the initial moisture content, void ratio, scale and overburden stress. On the other hand, setbacks encountered are with the sample scale and the initial moisture content effects on engineering applications in field conditions. Accordingly, in this study, the effect of both the initial moisture content (ranging from 55% to 105%) and the sample scale on the compressibility parameters was investigated. The outcome showed that there is a positive correlation of 0.546 between the initial moisture content and the coefficient of consolidation (c(v)), and 0.162 and 0.026 with the compression index (c(c)) and the coefficient of volume of compressibility (m(v)) respectively. Also, c(c) with the sample scale has a negative correlation factor of 0.115 and -0.085 (for sample height and diameter respectively). This shows that as the sample height and/or diameter increases, c(c) has a tendency to decrease. It was similarly observed that mv fluctuates with an increase in the sample scale and pressure until a pressure of 220kPa +/- 3.7kPa, where the value decreases. Hence, there is no significant influence between cc and mv.