01551363

Component

Characterization of scour due to free fall of water during storm surge is important for transportation related structures. The roads and streets behind levees are the most typical structures, which are vulnerable to storm surge. A sustained storm surge overtopping a floodwall or weir can cause scour of landside embankment soils, which can compromise embankment stability. Presence of wave action also contributes to scour progression and loss of lateral support. As lateral support is reduced, the overloaded retaining structure can start tilting and exacerbating the instability. Scour depth and stresses due to vertical flow are dependent on shear stresses induced by the plunging water or vertical jet, height of the wall, storm surge and wave heights, depth of the plunge pool on the landside of the retaining structure or a floodwall, and erosion rate of the levee soils. This paper focuses on estimating scour depth and hydraulic stresses imposed by overtopping due to a sustained storm surge. The analysis results are compared to observed scour depths on the landside of floodwalls after Hurricane Katrina along the Inner Harbor Navigation Channel (IHNC). The findings show that for transportation structures which are prone to water free fall during storms, it is important to consider impinging effect of water on soil supporting transportation structures.

This paper was sponsored by TRB committee AFP40 Physicochemical and Biological Processes in Soils.

01550057

15-1196

English

11p

2015

Transportation Research Board 94th Annual Meeting

Digital/other

Figures; Photos; References

Erosion; Floods; Free fall; Levees; Scour; Storm surges

Hurricane Katrina, 2005

Inner Harbor Navigation Canal (New Orleans)

Bridges and other structures; Geotechnology; Highways; Hydraulics and Hydrology; I42: Soil Mechanics

Transportation Research Board Annual Meeting 2015 Paper #15-1196

TRIS, TRB, ATRI

Dec 30 2014 12:28PM