General Modeling Tips

The following are general guidelines and tips that should be kept in mind for Slide groundwater analyses.

  1. In general, large contrast in permeability for two adjacent material cause numerical instability. The use of appropriate hydraulic permeability function solves some of these problems.  Refining the mesh may also help alleviate numerical issues.
  2. The “Simple” permeability function is only meant to give you reasonable results for the phreatic surface location for steady-state seepage analysis. For more realistic groundwater results you need to use actual permeability function or more sophisticated hydraulic conductivity functions such as the Van Genutchen or Gardiner models.
  3. The transient analysis requires an initial state of the pore water distribution in the model. The starting point is crucial for the stability and convergence of the solution.
  4. For the case of initial dry soil, the precision of the water content curve plays the major role that affects the solution. Therefore, a rough and preliminary model like the “Simple” function is not suitable for such analysis.
  5. The groundwater compute engine in Slide solves steady-state and/or transient seepage analysis as a standalone module without the need to do any slope stability analysis after.
  6. The FEA seepage analysis in Slide is very powerful and useful tool for analyzing seepage flow and discharge quantity. Lack of field data for any numerical analysis reduces its usefulness.  But, these tools can be used to explore what if scenarios and check several cases of interest. In seepage analysis, you might have some idea on water level at specific location at your site from standpipes or wells which will be a start-up location to specify the required boundary conditions for the model.