Soil deposits along a significant part of the Brazilian coastline consist of plains with geotechnical profiles presenting a high water table level, low strength and high compressibility. With urban growth, areas where the thickness of the soft clay deposit can reach up to 40 m are becoming more and more occupied. In this scenario, reinforced embankments on piles have been increasingly used to stabilize embankments over soft soils. The presence of the reinforcement reduces the stresses transferred to the soft foundation and improves the efficacy of the transference of loads to the piles. Therefore, significant reductions in fill settlements and in lateral displacements of the soft soil can be obtained. However, the design of this type of work is still complex. Several researchers have studied this technique with the purpose of improving the understanding of the mechanical behavior of these embankments, either by means of in situ instrumentation, numerical analysis or laboratory tests on physical models. This paper investigates the effects of mechanical damages in the reinforcement on the performance of the system. Three different reinforcement types, including a geogrid and two geotextiles, were tested with varying values of tensile stiffness. A typical piled embankment section consisting of an instrumented fill layer subjected to surface surcharges of up to 40 kPa (200 kPa under prototype conditions) was simulated in the laboratory. Test measurements are presented and discussed. The results obtained show the levels of mechanical damage to the reinforcement and their influence on embankment performance.
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