Influence of Heterogeneous Arrangements of Reinforcements’ Length and Stiffness on the Deformation of Instrumented Geosynthetic-Reinforced Retaining Walls Constructed with Sustainable Locally Available Backfill Soils

Abstract

Sustainable solutions involving geosynthetic-reinforced soil walls have been achieved in projects that use locally available backfill materials and a reduced volume of geosynthetic reinforcements. Different arrangements of reinforcements can be adopted to reduce the volume of geosynthetics. This paper reports the deformation measurements taken from four instrumented geosynthetic-reinforced soil walls constructed with different arrangements of reinforcement layers including different lengths and tensile properties. The deformation of walls with rigid reinforcements at lower elevations and more flexible at upper portions of the wall height was compared to walls with a uniform distribution of reinforcement layers. Similarly, the effect of the nonuniformity of reinforcement lengths along the wall height was also evaluated. Relatively short reinforcements (L/H < 0.7) used at deeper reinforced layers were observed to overload the upper reinforcement layers resulting in mobilized loads higher than expected, resulting in increases of approximately 80% in the wall’s deformation. In contrast, the use of rigid reinforcements at lower layers led to a reduction in facing displacements of 50% at lower instrumented layers and of 60% at upper instrumented layers. The distribution pattern of facing displacements, reinforcement-mobilized loads and strains along the wall height was significantly affected by the adoption of heterogeneous reinforced layers.