Consolidation characteristics of silty soils

The amount of settlement of soil layers is determined by the compression parameters obtained from the consolidation experiments. Standard oedometer test is an experiment developed by Terzaghi for one dimensional consolidation of saturated clays. In this study, consolidation characteristics of silty soils have been investigated by means of oedometer experiments. In this study, compression parameters of silty soils with different clay ratios and preconsolidation values obtained by using different methods have been investigated. For this purpose, consolidation experiments have been carried out on the specimens prepared by adding clay at a certain ratio to the the silt sized grain samples extracted from the silty soil obtained from Adapazarı city. In this study, 8 mixtures with different silt and clay ratios have been prepared in the laboratory. The physical properties of these samples have been determined from the consistency limit values and grain distribution curves obtained using the Casagrande and cone penetration method and sedimentation experiments such as hydrometer and pipette analysis respectively. These samples were consolidated under 100 kPa stress which are then subjected to consolidation tests using the classic oedometer instrument. The pre-consolidation pressure values have been determined based on the obtained consolidation curves by employing 6 different methods. In addition to this, using the data obtained from the experiments, compression coefficient, consolidation coefficient, compression index and reloading index of each sample are calculated and the results obtained have been compared. Keywords: Silt, clay ratio, consolidation, odometer, pre-consolidation pressure, coefficient of consolidation, settlement coefficient, compression index, reloading index.