Author(s): S. Amin Masoudzadeh; M. Mohsen Toufigh; Hessamy Azdani
Linked Author(s):
Keywords: Unsaturated flow; Effective stress; Infiltration; Groundwater level
Abstract: Infiltration to the soil take place in two ways, artificial recharge and natural events that both directly influence on the groundwater level, pore pressure calculation and flow analysis. Groundwater level is almost on the depth and flow of water must cross an unsaturated soil so what is governing on these problems is unsaturated flow equations. In addition, when water flows to the soil, the groundwater level will rise and pore water pressure increases. We know the theory of Terzaghi indicates that with increasing in pore pressure, the effective stress will decreases. But it has been understood from review in result of site investigation in Kerman (city of Iran) that somewhere the level of groundwater is getting up, otherwise what we expect form Terzaghi’s theory, the land have been settled in case the stresses with two recently explanation are strongly decrease. On its way through unsaturated soil, downward flow of water inserts some forces to the soil whereas they should be considered. There are something else that make the problem more complicated, With adding water, the hydraulic conductivity, total stresses and saturation degree have always changes and taking them to the conversation needs to solve coupled problem that it might be more difficult with analytical solutions. In this paper we want to consider what else would have effect on the stresses such as infiltration rate and hydraulic conductivity in downward unsaturated flow. And with a review in Bishop theory, presented solution for pore water pressures and some simplification that have not strong effect, we will try to calculate these inserted forces to the soil. As a result, with conservation of all these things, the real effective stresses will be calculated that sometimes they might be more than what we expect.
Year: 2016