Maximum outer-bank velocity reduction for vane-dike fields installed in channel bends
Date
2011
Authors
Scurlock, S. Michael, author
Cox, Amanda L., author
Thornton, Christopher I., author
Baird, Drew C., author
Colorado State University, publisher
Journal Title
Journal ISSN
Volume Title
Abstract
Hydraulic conditions associated with channel bends in meandering rivers include secondary, helical currents, mass shift of flow to the outside of the bend, and increased erosion along the outer streambank. Such outer-bank erosion may result in undesired plan-form migration of the stream course, placing valuable land holdings or infrastructure in jeopardy. A type of instream transverse rock structure, the vane dike, has been installed in field scenarios to mitigate problematic hydraulics associated with migrating river bends. Flows around vanes and similar structures have been modeled extensively in the past, both physically and numerically, yet, guidelines optimizing key state parameters for the installation of vane dikes in series are still unrealized and application of previous results are generally site specific. Emphasizing the stabilization of the upper reaches of the Middle Rio Grande River below Cochiti Dam, two scaled channel bends were physically modeled with installed vane-dike fields. Structure plan form angle, vertical angle, spacing, and length were altered between testing configurations and comprehensive data collection was performed. The reduction of the outer-bank velocity magnitude was quantified and non-dimensionalized for each tested vane-dike configuration. An approach predicting the outer-bank velocity reduction was developed for collected laboratory data, which approximates vane-dike field velocities for both channel bends with a coefficient of determination of 0.841.
Description
2011 annual AGU hydrology days was held at Colorado State University on March 21 - March 23, 2011.
Includes bibliographical references.
Includes bibliographical references.