AN EMBANKMENT FAILURE ON SOFT FISSURED CLAY

Construction at the Genesee Power Project near Edmonton required 13 m high approach fills on soft clay for a roadway overpass structure. During construction, the north approach fill failed at a height of about 12 m. An investigation of the failure was carried out and a monitoring program instigated for further fill construction and piling for the overpass structure. Monitoring data for construction after the failure are presented and discussed. The effective stress path/yield envelope approach was used to assess the data. An empirical performance criterion for the site was developed for the overpass structure based on the observed deformation rates and computed factors of safety.