Loading...
Search for:
richards-equation
0.005 seconds
Numerical Model for Slope Stability Assessment with Considering Hydrological Processes & Vegetation Influences
, M.Sc. Thesis Sharif University of Technology ; Ashtiyani Attayi, Behzad (Supervisor)
Abstract
Landslides are one of the most serious natural hazards in terms of victims and economic impact. This instability not only causes direct loss and causality but also intensifies instability’s compensation because of casualty in major transportation systems such as highway networks and connection networks such as electrical wires. Iran with mountainous nature and seismically active areas provides potential for broad instability. Thus determining the treatment of slope in response of time and different condition has significant inportance. The essential analysis for controlling instability is analysis of the slope resistance which results safety factor. This analysis is for assessment of...
Comparison of finite difference schemes for water flow in unsaturated soils
, Article World Academy of Science, Engineering and Technology ; Volume 40 , 2009 , Pages 21-25 ; 2010376X (ISSN) ; Ataie Ashtiani, B ; Sharif University of Technology
2009
Abstract
Flow movement in unsaturated soil can be expressed by a partial differential equation, named Richards equation. The objective of this study is the finding of an appropriate implicit numerical solution for head based Richards equation. Some of the well known finite difference schemes (fully implicit, Crank Nicolson and Runge-Kutta) have been utilized in this study. In addition, the effects of different approximations of moisture capacity function, convergence criteria and time stepping methods were evaluated. Two different infiltration problems were solved to investigate the performance of different schemes. These problems include of vertical water flow in a wet and very dry soils. The...
A modeling platform for landslide stability: A hydrological approach
, Article Water (Switzerland) ; Volume 11, Issue 10 , 2019 ; 20734441 (ISSN) ; Ataie Ashtiani, B ; Sharif University of Technology
MDPI AG
2019
Abstract
Landslide events are among natural hazards with many fatalities and financial losses. Studies demonstrate that natural factors such as rainfall and human activities such as deforestation are important causes of triggering a landslide. In this study, an integrated two-dimensional slope stability model, SSHV-2D, is developed that considers various aspects of hydrological effects and vegetation impacts on the stability of slopes. The rainfall infiltration and water uptake of roots change the water content of the unsaturated zone. The temporal and spatial distribution of water content is estimated in the hydrological unit of the developed model. The vegetation unit of the model considers...