THE IMPACT OF THE DIAMETER TO HEIGHT RATIO ON THE COMPRESSIBILITY PARAMETERS OF SATURATED FINE-GRAINED SOILS

Abstract

Compressibility parameters of fine-grained soils are mainly influenced by soil mineralogy, moisture content and soil diameter to height ratio (D/H). The British and American standards suggested that to obtain accurate engineering properties; it is necessary to use D/H ratio of 4 and 2.5 respectively to eliminate friction between the soil and the structure. In the current study, various D/H ratios were adopted ranging from 0.5 to 11. The D/H ratios effect on some compressibility parameters such as coefficient of consolidation (c v), compression index (c c) and coefficient of volume compressibility (m v) were analysed. Additionally, the impact of the D/H ratio on the acquire c v values were also presented where three methods were used namely: Casagrande, Taylor and Inflection method. The scaling effects based on c v ratio [c v (√t) / c v (log t)] from Oedometer tests using different D/H ratios are also presented. The results showed that Taylor's method is the most appropriate way to achieve an accurate c v and an increase in pressure leads to a reduction in c c and a gradual decrease in m v. The validation of the experimental results on a finite element software package PLAXIS was completed.