Design and Construction of a High Soil-Reinforced Segmental Retaining Wall Using Cohesive Backfill

Abstract

The GlenEagles SRW wall is a 500 m long reinforced-earth structure, with a maximum height of 10.5 m and an average height of 7.5 m. Preliminary design was in strict accordance with conventional design principles (i.e., NCMA guidelines). The preliminary design was deemed overly expensive, and hence a literature review was conducted to identify research on design innovations that could be implemented to reduce the cost. It was found that the knowledge of the mechanics of reinforced-earth SRW behaviour has advanced significantly since the NCMA guidelines were formulated, and that the conventional design methods as presented in the NCMA and FHWA Design Manuals are in some areas overly conservative. The objective of this paper is to identify certain design guidelines that can be safely relaxed, leading to a more economical design. The paper describes the early design of the wall, the design innovations, and the construction of the wall. It also discusses various issues encountered before, during and after construction that had an important impact on quality and cost.