Emergency Repair of CSAH 42 Landslide

摘要

During high river levels in the Spring of 2003, a portion of a slope along the Mississippi riverbank abutting CSAH 42 in Wright County, Minnesota failed. The landslide area comprised approximately 260 lineal feet of roadway/riverbank, extended approximately 5 ft into the existing pavement and was approximately 50 ft above existing river levels. A geotechnical investigation, temporary arrest of the slope failure and emergency repair of the riverbank was requested by the Wright County Highway Department. The geotechnical investigation involved a soil boring program, a topographical survey, and a research of Mississippi River flood data. The cause of the failure was first investigated. A geosynthetic reinforced repair design combined sheet pile and benway weir flow diversion, riprap cover in the floodplain and a cellular confinement system over a 1H:1V reinforced slope. Special permits were acquired through the Minnesota Department of Natural Resources, US Army Corps of Engineers and Wright County. Within 2 months the project was evaluated, designed and plans/specifications prepared. Construction began in September, 2003. The road was closed, a detour implemented and the failure scarp removed. The construction progressed ahead of schedule and the reinforced slope was completed up through the placement of the bituminous base in early November, 2003. The final wear bituminous pavement was completed in Spring 2004. The work was paid for through a State Aid Emergency Disaster Fund.