Finite Element Investigation on Patterns of Soil Arching in a Geosynthetics-Reinforced Piled Embankment

The shape of soil arch is a key parameter in modern design of piled embankment. Design guidelines for piled embankment in the Netherlands, Germany, and the United Kingdom have been updated in 2011 to consider the improved understanding of the arching mechanism. Recently in Korea a national research project on the design code of the geosynthetic-reinforced piled embankment is being conducted. As part of the project, a series of finite element simulations have been performed. Numerical study mainly focuses on the visualization of soil arch under various different parametric conditions. By taking the local extremes in the vertical distributions of the vertical stress obtained from numerical simulations, the shapes and sizes of the soil arch zone were estimated. Numerical results show that the size of the dome-shaped soil arch zone remains constant in variation of the cohesion and friction angle of the fill material. However, the stiffness of the soft material between piles has a significant influence on the height of the soil arch zone. For the sufficient low stiffness of the soft material, the height of the dome-shaped soil arch zone is approximately 42% total embankment height.