This study numerically evaluated the combined effects of different controlling factors (i.e., wall height, stresses induced during backfill compaction, reinforcement stiffness, toe conditions, and facing stiffness) on the behavior of geosynthetic-reinforced soil (GRS) walls under working stress conditions. The results were compared with values predicted by different currently used methods. It was shown that toe resistance has a major effect on the prediction capability of those design methods. Parametric analyses have shown that the amount of tension in the reinforcement varies with restraint at the base of the block facing. For free-base conditions with a constant value for reinforcement stiffness, the tension in the reinforcements was the same irrespective of the facing stiffness and the wall height. For the fixed-base conditions, the amount of tension in the reinforcements and horizontal toe load varied as a function of the facing stiffness. Comparing individual measurements of reinforcement tension verified the significant effect that the toe restraint has on the amount of tension mobilized in the reinforcements at the bottom of the wall. The results showed that the amount of tension in the reinforcement is a function of the magnitude of the compaction-induced stress and the reinforcement stiffness. These results indicate that the compaction-induced stress does not significantly affect the magnitude of the horizontal toe load.

The paper presents the behaviour of two reinforced test embankments built on a normally consolidated soft clay deposit underlying a top sand layer. The embankments were constructed close to undrained conditions in about 60 days. The embankments were well instrumented, including measurements of tension forces in the reinforcement. The mobilised tension forces in the reinforcements were shown to increase with embankment height and larger values of tension forces were measured in the embankment built on a shallower clay layer. The critical failure surfaces obtained in limit equilibrium stability analyses were close to the observed field failure surfaces. These analyses used measured reinforcement forces and resulted in Bjerrum correction factors around μ = 0.60 for the two embankments. These analyses considered the measured reinforcement forces and three-dimensional effects. Consistent correlations were obtained between embankment loadings, factors of safety, measured reinforcement forces and inclinometer readings.

This paper evaluates the significance of basal reinforcement and the presence of the surface sand layer in the stability. This evaluation is carried out by means of field measurements and stability analyses of three test embankments on soft clay taken to failure. Two of the test embankments were reinforced and one was unreinforced. Stability analyses were carried out taking into account measured values of reinforcement tension forces during construction. The set of analyses have shown that the top sand layer was more important to the stability of the embankments than the basal reinforcement. The cases studied have also shown that the conventional design practice that assumes for the reinforcement a fixed tension contribution may lead to unrealistic higher factor of safety.