Slope stability evaluation is one of our specialties. Slopes can become unstable due to precipitation, loss of soil strength, loss of toe support or earthquake forces. Some slopes need special attention due to their geometry or soil strength. For examples silty soils and 1.5:1 slope gradient.

We start with geotechnical evaluation in the field and augment it with laboratory testing.  Then we use in house and commercial slope stability software to analyze the existing slope factor of safety.  We are looking for Static factor of safety for the slope that exceeds 1.50 and for seismic slope stability factor of safety that exceeds 1.10. Based on these results, we come up with slope repair options. Approx. 20% of the slopes we analyze are stable but may need proper ongoing maintenance.

Pipe and Board Slope Pic ASCENDING SLOPE failed slope2   

The principal engineer occasionally teaches seminars in earth retention and slope repair.

In the past we have the following repair methods:

  • Geogrid reinforcement with keyway & subdrain system
  • Soil-Cement mix and 93% compaction & subdrain system
  • Helical pile tieback anchors with grade beam & subdrain system
  • Tieback anchors with grade beam & subdrain system
  • Terraced retaining walls on shallow foundation system
  • Terraced retaining walls on drilled piers & grade beams
  • Soil nail wall system

The solution depends on your slope geometry, soil material, and structures at crest and slope toe. Because one firm does the geotechnical and Repair plans, the solution is more economical. We use in house software & verify it with secondary slope stability program.


Slope repair Slope repair

static slope stability SF