Seismic Characteristics of a Geotextile Tube-Reinforced Embankment and Shallow Foundations Laid on Liquefiable Soil

The ground in Saemangeum has a high water level and is mostly composed of silty soil and sand, which makes it susceptible to liquefaction and seepage effects. To investigate the seismic response of a geotextile tube-reinforced embankment and shallow foundations laid on a liquefiable soil, a simple spring type shaking table apparatus was developed. The variation in the response acceleration and shear stress-strain relationship were investigated, and the effect of soil improvement and reinforcement were explored, wherein one of the shallow foundations was laid on a coarse sand layer and reinforced by a polyester geotextile. The results showed that the main cause of damage to the embankment was seepage-induced liquefaction. Excessive surface accelerations were observed in the embankment soil due to lateral spreading, indicating the importance of analyzing the liquefaction potential of soils not only at the site area but also near embankments. Lastly, the inclusion of geotextile reinforcement and soil improvement only resulted in the slight reduction of shallow foundation settlement.