FEM analysis of high airport embankment with horizontal drains

摘要

A fill of Noto Airport has been constructed rapidly to a height of 55 m, and its filling material is high water content clay. Geotextile horizontal drain is installed in the fill to accelerate consolidation. To seek reasonable method to simulate the behavior of a fill with horizontal drains, an elasto-visco-plastic FEM is applied in this paper. The result of the simulation agreed well with observed deformation and monitored stress, but horizontal deformation of the fill body measured is much smaller than estimated by FEM. It probably implies that the reinforcing effect due to friction between the soil and the geotexitile is generated in the field, but is not well-modeled in the analysis. Some trial FEM calculations are carried out for various hypothetical cases of field conditions such as filling speed and permeability of filling material. It is shown that the FEM capable of adapting complicated conditions at a given site enables rational design for embedding horizontal geotextile drains.