Date of Award
Bachelor of Science (BS)
Dr. Scott F. Korom
This design investigates stabilization methods for a failing levee system using the method of slices. An assumed failure surface was drawn and divided into vertical slices, where the forces acting on each slice were analyzed. If the forces available to resist movement were greater than the forces driving movement, the slope was considered stable (Rahn 1996). A factor of safety was then calculated by dividing the forces resisting movement by the forces driving movement. A factor of safety of 0.987 was initially obtained, which meant failure at the toe of the embankment was occurring. With the addition of a 4 ft deep, light weight aggregate (LWA) fill, a factor of safety of 2.139 was obtained. However, a preferred factor of safety of 3-4 is considered appropriate when the failure of the structure could cause widespread flooding (Das 2002). This can be achieved by either the addition of more LWA to strengthen the underlying clay, or through the addition of sheet piles or a retaining wall, neither of which were looked at for this specific design.
It was also determined that further compaction of the fill material may be a solution to this problem, or the excavation of top sediments and replacement with LWA could be an alternative. The addition of LWA would lower the vertical and horizontal forces on the embankment, but the excavation of soil, and the compaction and addition of new fill may not be a cost effective choice.
Lammers, Heather N., "Levee Stabilization Design for Flood Control in East Grand Forks, Minnesota" (2007). Undergraduate Theses and Senior Projects. 93.