and Water Engineering > Modeling
Software > Slope
Stability Software > XSTABL
XSTABL v5 -- An Integrated Slope Stability Analysis Program
for Personal Computers
Description of XSTABL
XSTABL provides an integrated environment for performing slope stability
analyses on an IBM personal computer, or compatible, running MS-DOS. The
program provides an intuitive user friendly interface and the analytical
philosophy behind the popular slope stability program STABL, which was
developed at Purdue University.
The Generalized Limit Equilibrium (GLE) method has been implemented in
XSTABL. This method allows factors of safety to be calculated for force
and moment equilibrium or for force equilibrium only, using different
interslice force angle distributions.
With this approach, the user can readily calculate the factor of safety
according to Spencer's, Morgenstern-Price, or one of the methods
proposed by the Corps of Engineers.
If an analysis requires a search for the most critical failure surface,
the simplified Bishop and Janbu methods of analysis are selected due to
their relative ease of use.
The program may be used to either search for the most critical circular,
noncircular, or block-shaped surface, or alternatively, to analyze a
single circular or non-circular surface.
The critical surface is identified by automatically generating and
analyzing failure surfaces between defined initiation/termination ranges
or by connecting points randomly located within search boxes specified
by the user.
This aproach minimizes the required input parameters and can be
effectively used to confine the surface generation within a narrow,
The soil strength along the failure surface may be described as either
conventional (i.e., C, ø), undrained or non-linear Mohr
can be either isotropic or anisotropic. The undrained strengths are
assigned as a function of the vertical effective stress.
For effective stress analysis, pore water pressure may be simulated by
- A piezometric surface;
- Multiple phreatic surfaces;
- Pore water pressure grid;
- Constant pore pressure;
- Pore pressure parameter ru.
[Adapted from XSTABL v5 brochure, 6/1/94]
The USFS has a site license for use of the XSTABL software. We may use
it for official USFS work only. Contractors may use a Forest Service copy
of XSTABL for work on official FS projects, but must surrender
to the Forest Service all copies of the software at the completion of
If you are using XSTABL and have not notified our office, please let us know,
so we can more easily keep Forest Service XSTABL users aware of new versions.
To get a copy of XSTABL:
Contact the Regional Engineer at the Regional Office. He or she
will have been supplied a copy of XSTABL and several manuals for
distribution within the region. Those in Forest Service Research
should contact a nearby Regional Office for a copy.
Then, please notify
that you have a copy, so that we can let you know of updates to XSTABL,
or other important issues, and
read our hints on using XSTABL
under current Forest Service machines.
If XSTABL is not available to you through these channels, you can
download the software
over the Forest Service Intranet.
This site is accessible only to Forest Service computers.
We can not supply XSTABL for non-Forest Service use.
It is available commercially from the developer:
Dr. Sunil Sharma
Interactive Software Designs, Inc.
For more information on XSTABL, select one of the following: