## Infinite Slope v. 3.0 features

The graphical interface included in version 3.0.

**Included features**

The position of the free phreatic surface has a determinant role on the stability conditions, therefore it is very important to be able to control its depth

*Z*

*.*

*w*The polygon of forces for the slice is useful to control how the equilibrium evolves when changing a parameter.

While the user can evaluate the factor of safety

*F(Z)*for a generic slip surface (at depth

*Z*) often it is necessary to compare the obtained value to the minimum value of

*F*(at depth

*Z*

*crit*) called the

*Factor of safety*of the slope.

All main variables can be controlled in interactive mode in order to understand their influence with an immediate visual perception.

The presence of the bedrock at depth

*Z*

*bed*helps to give a lower bound to the depth of the failure surface, which makes the research of a critical depth

*Zcrit*more realistic.

All features included in version v. 3.0 are listed below:

- It is possible to input a project title.
- Input of weights can be assigned either via porosity
*n*and unit weight of solids*γs*or directly through*γsat*,*γ*and*γd*. - Unit weights of the soil are considered separately above and below the groundwater surface.
- Unit weight above groundwater surface can be given as dry, unsaturated, saturated.
- Depth
*Zw*of groundwater free surface is an independent variable. - The presence of the bedrock, at a depth
*Zbed*, helps to give a lower limit for the development of a failure surface, which makes more realistic the research of a critical depth zcrit (at which the factor of safety*F*is minimum). - The factor of safety
*F(Z)*can be calculated at any imposed potential slip surface at depth*Z*. - The Factor of Safety
*F*of the slope, which represent the minimum value corresponding to the critical slip surface (at depth*Zcrit*) is always calculated and displayed for safety reasons. - Back analyses of a failure conditions to determine
*φ'*or*c'*are available. - The visual approach helps to: better understand the influence of the parameters; explore quickly the possible solutions and interpretate the results.
- The graphical interface is improved and is continuosly updated with clear dimensions and indications.
- A sketch of the longitudinal section of the slope is shown and continuously updated.
- A sketch of the cross section of the slope is shown and continuously updated.
- The polygon of forces which verifies the equilibrium of the slice is continuosly displayed.
- Suggestions and warnings about input data and about the results are proposed.
- It is possible to change the minimum allowable value of the Factor of Safety.
- Forces, stresses and pore pressures calculated for the single slice of unitary width are displayed in a table.
- Mohr-Coulomb's failure criterion are implemented.
- A rigid-perfectly-plastic constitutive law is adopted.
- Both static condition and seismic (pseudo-static) force can be considered by the use of the horizontal and the vertical component.
- It is possible to design interventions as the use of drainage trenches or bored pile walls.
- Stability assessments for the current slope and for the final slope as designed are constantly updated.
- It is possible to save and open an analysis projects.
- An analysis report can be printed.
- A preferences dialog allows to personalize the program interface.

**Limits of application**

At the moment this version has the following limitations:

- The model is suitable to analyse stability conditions of slopes with direction of stratification parallel to the slope. In many cases of mudflows and in any case where the failure surface is expected or found planar and parallel to the slope. For slopes made of fine grained soils in deep homogeneous layers the used model is often not suitable to represent a correct interpretation of failure mechanisms (circular or not planar) and isn't able to give a reasonable factor of safety for the slope.
- Groundwater flow must be parallel to the ground surface or absent.
- Seismic forces are pseudostatic and no dynamic effects is taken into account.
- Unsaturated soil theory is not applied.
- Only drained failure conditions are considered.

**Download page**