Effect of Soft Soil Model Parameters on Soil Behavior

Soft soils such as clays have a high porosity and demonstrate a high compressibility compared to other type soils. In oedometer testing, normally consolidated clays behave up to ten times softer than normally consolidated sands [1]. Clay soils have very low permeability which is highly important to govern consolidation rate. In this study, first task has been to investigate the primary consolidation behaviour of soft clay by using a large-scale laboratory oedometer test. The reconstituted specimen of kaolin clay was used to represent the soft clay. The kaolin powder was mixed at a water content of about 1.5 times the liquid limit and has been consolidated by the axial stress of 30kPa. Secondly, the effect of the soil parameters obtained from standard laboratory tests on soft clay behaviour was researched with numerical finite element analysis computations in Plaxis 2D. Soft Soil material model was utilized during the finite element computations and input parameters were calculated from standard laboratory tests. The simulations demonstrate that it is very important to determine appropriate model parameters for modelling soft soil behaviour