Evaluation of the accuracy of design methods for geosynthetic-reinforced piled embankments

Abstract

Geosynthetic reinforced piled embankments have been increasingly used as a solution to stabilize embankments on soft subgrades. Analytical methods have been commonly used in routine designs of such works and significant deviations between results can be obtained depending on the method considered. This paper investigates the accuracy of different analytical methods comparing their predictions with results of large scale tests. A section of piled embankment consisting of an instrumented fill layer subjected to varying values of surface surcharge was simulated in the laboratory. Four different reinforcement types were tested. The results of the tests are presented and discussed, and statistical analyses were carried out to assess the accuracy of each method with regard to pile efficacy, maximum fill settlement and reinforcement strain. The results showed that the identification of the most accurate and precise method depends on the statistical criterion used. However, in general, the methods based on the concentric arches theory, the modified British method (BS-8006) and the German method (EBGEO) were the ones that showed the best predictive capability.