Challenges faced in design construction of 12 m high geosynthetic reinforced soil slope repair in urban setting

摘要

The first geogrid reinforced soil structures in North and South America were built in southern Ontario, Canada in the early 1980s. These first structures were steep slopes, typically built at 45°, with a vegetated face. Since then, the design and construction techniques have evolved due to many innovations and refinements. In the City of Mississauga, Ontario, a recently designed and constructed geogrid reinforced soil slope utilized many of these innovations and refinements. The repair of this 12 m high slope failure along 100 m of the Etobicoke Creek presented many geometric and geotechnical challenges that required some unique and powerful solutions. Some of these challenges were due to the urban setting. At the top of the slope sits a residential townhouse development. Underground utilities sit in the rear yards beyond the shoulder of the slope with sanitary sewer pipes running beyond the toe of the slope in the floodplain below. In order to protect the safety and integrity of the townhouses, the underground utilities and the sewers, the slope failure had to be repaired in a timely and economical manner while blending in with the natural ravine environment. This case study will describe how these challenges were addressed during the design and construction of this geogrid reinforced soil slope repair in an urban setting.