Settlements of Existing and Widened Embankments over Soft Soils

Abstract

Increased traffic volume has made it urgent to improve highway capacities by widening the existing embankments in south-eastern coastal areas of China. Adding a new embankment adjacent to the existing embankment will result in additional settlement within the existing embankment. And also, differential settlement will occur between the existing and widened embankment over soft soils. Excessive settlement and/or excessive differential settlement may cause longitudinal cracks, drop-off on the road surface, even local or global instability. A numerical analysis was conducted to investigate the influence of the thickness of soft soils on the development of settlements of the existing and widened embankment. The effect of widening time on the settlements was also discussed. The results indicate that the thicker the soft soils, the more time needed for the existing embankment to reach its final settlements. It is also found that there exists a most appropriate widening time for minimizing the additional settlements of the existing embankment on soft soils with a given thickness.