Numerical Investigation of Subgrade Reaction Coefficient in Sand Soils of Bandar Abbas City

The soil-foundation interaction is one of the most important issues in geotechnical engineering that deals with studying the soil behavior subjected to the side loading. Winkler’s model is the first and simplest method for consideration of the soilfoundation interaction. It is vitally important to determine the coefficient of subgrade reaction of the soil. Since several methods have been provided to estimate the coefficient of subgrade reaction up to now, this research is conducted to choose a ground characteristic in Bandar Abbas (IRAN). To do so, the obtained results from the proposed experimental formulas are compared with corresponding values of the behavioral models to determine the coefficient of subgrade reaction. In addition finite element analysis is performed using Plaxis software. The result of this paper shows that the finite element method is more compatible than Biot's method. Results also showed an increasing footing diameter which leads to the decrease of the Ks. This fact is because of an increasing load area which concluded to the increasing of the settlement. It is found that with increasing each of the strength parameters of the soil (c, ∅) can be expected an effect on increasing the subgrade reaction; although this increase depends on footing diameter. Also, in sand soils, the cohesion of the soil is more effective on the increase of the subgrade reaction coefficient than the internal friction angle.