Analysis of Bank Stability in the DEC (Demonstration Erosion Control) Watersheds, Mississippi
Abstract
Many bluff-line streams in Mississippi are experiencing serious instability as a result of channel degradation. Degradation lowers the bed of the channel, leading to undermining of bridges and other structures and the generation of heavy sediment loads that cause aggradation problems further downstream in the systems. Bed lowering also increases bank heights and angles, reducing bank stability with respect to mass failure under gravity. Eventually, as the bed lowers, the banks become unstable and collapse. The critical height and the mechanism of failure are functions of the bank geometry and the engineering properties of the bank materials. When the banks attain the critical height for mass failure a major geomorphic threshold is crossed and the thrust of channel instability switches from degradation to rapid widening. Channel stabilization in the Bluff-line streams is a major aim of the Demonstration Erosion Control (DEC) Project. In the DEC studies, it would be very useful to be able to predict the critical bank height as a function of the bank geometry and bank material properties. In this report bank stability analyses recently developed by Osman and Thorne are used to develop generalized bank stability charts that may be used to predict critical bank height.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 04, 1988
- Accession Number
- ADA196006
Entities
People
- Colin R. Thorne
Organizations
- Queen Mary University of London