Reinforced earth (RE) walls, a type of mechanically stabilized earth walls, are escribed in this paper as a composite system consisting of alternating layers of granular backfill and discrete steel reinforcements connected to precast concrete facing panels. This paper discusses the current procedures used for the design and construction of relatively flexible RE walls over marginally stable soils for roadway applications. Three case histories of RE walls constructed over very soft clays, organic deposits and/or compressible waste materials are provided, with particular emphasis on the technical and practical factors that influence the design of RE walls over marginal lands.
Technical features that make RE walls a viable alternative to rigid cast-in-place tructures for roadway applications are provided. The design of the facing panels, steel reinforcements, and backfill used in RE walls constructed over marginal soils is also discussed. Foundation improvement techniques that were used in the case histories to further reduce the risk of differential settlement due to the uncertainty in the predicted behavior of the material over time are also provided.
It is demonstrated that RE walls may be designed to accommodate large total and ifferential settlements. Typically, simple construction techniques such as the use of vertical joints and staged construction may be used to increase flexibility and stability of E walls. The paper concludes by providing a summary of the design and construction practices that will improve the aesthetics, cost, safety and durability of RE walls.