Reinforced soil highway slopes are an economical alternative to conventional grade separations within limited rights-of-way, such asflattened slopes, selected-fill embankments, or vertical retaining walls. Reinforced soil slopes are applied in six main areas of highway construction: steepened slopes, surficial reinforcement, compoundslopes for road widening, repair of landslides, embankments over soft foundations, and vertical slopes or walls. Critical applications with a design life of 50 to 75 years and, therefore, grid geosynthetic reinforcement, are emphasized. Those applications are defined andillustrated and their relative economics are reviewed. Steepened embankment slopes are examined n detail. Economics are presented and compared with alternatives. Design of steepened slopes is reviewed with emphasis on stability analysis procedures and appurtenant features. Also, long-term reinforcement material property requirements andspecification writing are evaluated. Brief case histories are presented to illustrate applicability, aesthetics, and construction of reinforced soil slopes in highway works, showing that reinforced soil slopes are a proven method of construction having broad applicability in highway construction. It is concluded that highway planners androute layout engineers should consider the reinforced soil slope alternative(s) when faced with grade separations that must fit within limited rights-of-way. This paper appears in transportation researchrecord no. 1288, Geotechnical engineering 1990.
Samenvatting