Upgrading and reconstruction of a collapsed embankment founded on salty soil

摘要

Failure of a local drainage lake embankment has caused a disaster and initiated a full-scale study to upgrade and reconstruct a new one. An extensive field geotechnical study was conducted along the failed embankment to investigate the cause of its failure. The field study showed the presence of a high percentage of salts mainly sodium chloride in the surface layers. Washing the present salts with time might have been one of the main factors that caused the embankment failure. The survey of the area nearby the drainage lake and the laboratory results showed that the local suitable construction materials are not sufficient to construct a homogenous embankment. Therefore, it was decided to construct a zoned embankment. The embankment consisted of an impermeable core, three transitional layers, a filter, and protected shoulders. The surface salty layer under the base of the embankment was replaced with a compacted silty clayey sand layer with a minimum thickness of 2.0m. A numerical study of the embankment was conducted to investigate the behavior of the suggested cross section under working conditions.