Last Updated July 21, 2017

# Details

## Formulation

SLOPE/W is formulated in terms of moment and force equilibrium factor of safety equations. For example, the Morgenstern-Price method satisfies both force and moment equilibrium. This general formulation makes it easy to compute the factor of safety for a variety of methods and to readily understand the relationships and differences among all the methods.

SLOPE/W can use finite element computed stresses from SIGMA/W or QUAKE/W to calculate a stability factor by computing both total shear resistance and mobilized shear stress along the entire slip surface. SLOPE/W then computes a local stability factor for each slice.

Probabilistic analysis can be performed by using normal distribution functions to vary soil properties and loading conditions. Using a Monte Carlo approach, SLOPE/W computes the probability of failure in addition to the conventional factor of safety.

## Features

• Limit equilibrium methods include Morgenstern-Price, GLE, Spencer, Bishop, Ordinary, Janbu and more.
• Soil strength models include Mohr-Coulomb, Spatial Mohr-Coulomb, Bilinear, Undrained (Phi=0), anisotropic strength, shear/normal function, and many types of strength functions.
• Specify many types of interslice shear-normal force functions.
• Pore-water pressure options include Ru coefficients, piezometric lines, pressure contours, a grid of values, spatial functions, or finite-element computed heads or pressures.
• Define potential slip surfaces by a grid of centers and radius lines, blocks of slip surface points, entry and exit ranges, fully specified shapes, or automatic.
• Use probabilistic soil properties, line loads and piezometric lines.
• Transient stability analyses
• And many more!

## Integration with Other Applications

### Use pore-water pressures from SEEP/W, SIGMA/W, QUAKE/W or VADOSE/W

Using finite-element computed pore-water pressures in SLOPE/W makes it possible to deal with highly irregular saturated/unsaturated conditions or transient pore-water pressure conditions in a stability analysis. For example, you can analyze changes in stability as the pore-water pressure changes with time.

### Use stresses from SIGMA/W, or QUAKE/W

Using finite element computed stresses in SLOPE/W allows you to conduct a stability analysis in addition to a static deformation or dynamic earthquake analysis. For example, you can compute the minimum factor of safety that will be reached during an earthquake, or you can find the resulting permanent deformation, if any, using a Newmark-type procedure.