ABSTRACT
Geosynthetic reinforced soil walls are now a mature technology for the solution of earth retaining wall problems. In the USA they have been demonstrated to be 50 percent of the cost of traditional concrete gravity structures. Conventional Rankine and Coulomb earth pressure theories and slope stability methods have been adopted in modified form to carry out the analysis and design of geosynthetic reinforced soil walls. These methods are limit equilibrium approaches that assume simplified failure mechanisms and employ either global factors of safety (AASHTO 2002, Elias et al. 2001, NCMA 1997) or partial factors (BS8006 1995, AASHTO 2007) to design against serviceability failure and/or collapse (i.e. limit states design). However, the operational performance of these structures (i.e. under working stress conditions) is controlled by deformation limits that cannot be accounted for explicitly using limit equilibrium-based methods. In addition, reinforced soil walls are complex systems typically involving a structural facing (such as concrete panels or stacked modular concrete blocks), soil backfill and horizontal layers of polymeric reinforcement. Limit equilibrium and semiempirical analysis approaches require simplifying assumptions regarding the mechanical properties of polymeric reinforcement products and the interaction between components of reinforced soil wall systems. As a result, these approaches provide very limited insight into the fundamental behavior of reinforced soil walls since failure mechanisms are assumed a priori.
