Two-Dimensional Experimental and Analytical Investigations of Load Distribution on Piled Embankments

Soil arching occurs when differential movement develops. In geosynthetic-reinforced pile-supported embankments, soil arching occurs when the geosynthetic deflects in the area between the piles. Due to the soil arching, a relatively large part of the load (A) is transferred towards the piles directly, which reduces the residual load part (B) exerted on the geosynthetic reinforcement between the piles. This paper presents the results of experiments in a two-dimensional test set-up with analogical soil. The results of the experiments are analysed using analytical calculations. The set-up of tests was designed in a way that it was especially suitable for measuring these two load parts A and B separately. In this research, it was assumed that the subsoil between the piles was so soft that support of subsoil (load part C) is zero. Comparison of analytical calculations and tests just before rupture of the reinforcement showed that the fill height strongly affects the soil arching. For high fills, the vertical load concentrates on the reinforcement closer to the beams, effectively a more or less inverse-triangular load distribution. For relatively thin embankments, the load resembles more a uniform or triangular load distribution. The inverse-triangular load distribution in the higher embankments results in a steeper slope of the reinforcement at the edge of the beam. This makes the reinforcement more effective, so that more load can be transferred through the same reinforcement without rupture.