Retaining Wall Failure
Victor, Montana
Project included both horizontal and
vertical movement of an 8-foot vertical cantilever retaining wall
constructed upon a fill-slope. Orion Engineering interviewed
contractors involved with original construction, developed
cross-sections, provided foundation soils evaluation, and conducted
preliminary slope stability analysis and settlement
calculations. Determined that all noted distress was due to improper
soils compaction of fill material prior to placement of the retaining
wall. The noted distress agreed reasonably to that calculated, for
both horizontal and vertical components of settlement. Provided expert
witness deposition testimony.
Foundation Failure
Polson, Montana
The project included damage to an existing
residential home newly constructed upon a steep slope on the east
Shore of Flathead Lake. The foundation had failed in two places; the
home had literally broken in half. Subgrade conditions consisted on
fine-grained sediments with evidence of water seepage/piping. During
site reconnaissance, we noted a tension crack within the
hillside. Following slope stability computer modeling, we determined
that the existing slope had become unstable following excavation for
the homesite, and was triggered by a sharp rise in the phreatic
groundwater surface during spring runoff. Recommended remedial
efforts included installation of tension anchors and water drainage
systems.
