• XP/Vista/Win7/Win8 (32 and 64 bit)
  • 10 GB hard disk space
  • 2 GB memory (RAM)


  • Win7/Win8 (32 and 64 bit)
  • 20 GB hard disk space
  • 4 GB memory (RAM)

Underground Wedge Stability Analysis

version 4.0


Unwedge v3.0 Update History

Version 3.024 - May 29 2014

  1. Printing now includes end wedge data if they are turned on.

Version 3.023 - October 16 2013

  1. Can now export to excel from the combination analyzer. There is a button in the dialog.
  2. Can now export to excel (right-click menu) from the Chart View of the Tunnel Axis Plot.
  3. Can now plot Apex Height in the Tunnel Axis Plot.

Version 3.022 - October 8 2013

  1. Dips 6 support for importing joint sets.
  2. Google Chrome support was broken by a Chrome update. Reverting help to use IE.

Version 3.021 - September 20 2013

  1. Updated Help system to support Google Chrome and IE10.

Version 3.020 - November 19 2011

  1. Online Help would now launch in Internet Explorer if Google Chrome is the default browser. The online help does not properly work in Google Chrome.
  2. A rare bug would result in scaled wedges with huge volumes, much larger than the unscaled wedge.

Version 3.019 - March 1 2011

  1. Fixed a bug when scaling wedges.  By default when scaling wedges, Unwedge should determine the maximum volume wedge that meets the scaling criteria.  Under certain situations, this did not happen and a smaller wedge would be computed.

Version 3.018 - March 29 2010


Added Apex Angle as a method of sorting in the combination analyzer.

Version 3.017 - September 29 2009


Fixed the problem when using Copy to Clipboard from End Support Designer. The end wedges did not show up on the copied image. The only workaround was to use Print Screen or Export Image.

Version 3.016 - July 7 2009


Under rare circumstances the clipboard would be corrupted. Fixed.


Excel charting of multiple datasets would sometimes not work with Excel 2007.


Security system update to allow for educational updates and improve commercial network version.

Version 3.015


A new option has been added to set the water pressure to zero on the excavation surface for gravity water pressures. This is to model the zero water pressure condition at the tunnel face if drainage is allowed.

Version 3.014


Export image now works on Vista.

Version 3.013


Added warning when ratio of the excavation coordinates to the excavation dimensions is too large. Warning appears after adding an excavation boundary either manually or from a DXF.


Apex angle is now computed correctly according to the description in the help. It use to be the minimum of the angles between the 3 wedge edges, now it's the minumum internal angle between an edge and the opposite face.

Version 3.012


Swellex and Split-Set bolts now allow entry of a plate capacity.


Help Update.

Version 3.011


If a bolt excavation end point lay directly on an excavation vertex, then in some cases the bolt would not be included in the analysis.


Improved documentation for shorcrete shear strength and failure modes.


Lowered the default shotcrete shear strength to be more in line with Canadian codes for unreinforced concrete shear strength.

Version 3.010


New help system including new tutorials.

Version 3.009


If a horizontal plane intersects a horizontal tunnel at the first vertex, and was first in the plane order, negative values of volume and incorrect modes of failure would result.

Version 3.008


Now supports multiple HASPHL locks on the same USB hub

Version 3.007


The units for support pressure were displayed incorrectly as force units instead of the correct pressure units in both the infoviewer and the sidebar. Fixed.


New Hasp-HL hardlock support. Removed support for old beige hardlocks.

Version 3.006


Speed Improvements for the combination analyzer. Can now handle larger numbers of joint combinations. Hint: Turn of the calculation of end wedges in the project settings if you are not interested in end wedges. This greatly improves speed as well.

Version 3.005


If one of the joint planes making up a wedge was orthogonal to the plane of sliding, in shuch a way that there was no normal force on the plane but the wedge slides along the plane, cohesion on the plane was not being factored into the factor of safety. This resulted in factors of safety less than the true factor of safety. This is a rare case.


Dxf files with arcs using negative bulge factors would not be imported correctly.


Can now pan the perspective view.


Some very old files (from Unwedge for DOS version 1.x) would not
load properly (the unit system was not set properly, after the file load). Fixed.

Version 3.004


When calculating safety factors using stress analysis results, the program would overestimate the safety factor. The reason for this is in the fundamental formulation used that included shear stress as a driving force. This is wrong and has been removed. The program now closely matches Phase2 and UDEC numerical analysis results when looking at prismatic wedges (soon to be released!). It also matches analytical results presented in Brady and Brown "Rock Mecanics for Underground Mining" and papers published.


It was possible for bolts to unload a sliding plane to a point where contact was lost. This would result in a reduction in safety factor if cohesion on the sliding joint was used. The program has been updated so that contact is never lost, so cohesion always exists. As a result, increasing the bond strength or capacity will not result in a reduction in safety factor for this case.


Input data dialog restricted plunge to [0,90]. The allowable range is now
[-180,180] which is the same as the side bar.


Tunnel axis (optimization) plots would sometimes be blank for the "factor
of safety" plot if the "Wedges to Analyze" in the Tunnel Axis Plot Settings
was changed to a single wedge.


When using stress with joints that have different properties, the program might use the wrong set of properties on a joint plane.


On Windows XP, the scroll bars did work correctly for the list of possible variables, in the tunnel axis plot's "define user data equation" dialog.


The Barton-Bandis strength criterion has been updated to include the 70 degree maximum at low confining stresses (Barton and Choubey 1976). Phib has also been changed to Phir to better represent the current criterion. The help has been updated as well.

Version 3.003


The combination analyzer for support pressure was broken in version 3.002.

Version 3.002


For sliding wedges with stress, the weight was not being included in the driving force calculation.


Support for new Educational system. Also update dll's to latest microsoft versions.


Fix - the combination analyzer sometimes displayed values for "Required Support Pressure" that were too large. Only the values of "Required Support Pressure" in the combination analyzer dialog were affected. All other values in the dialog were correct, and the rest of the program was not affected. In all cases, the value that would be reported would be greater than (more conservative) or equal to the correct value.

Version 3.001


Release of Windows version of Unwedge.