Accession Number : ADA290618

Title :   Bank Stability Algorithm for Numerical Modeling of Channel Width Adjustment.

Descriptive Note : Interim rept. no. 3,

Corporate Author : NOTTINGHAM UNIV (UNITED KINGDOM) DEPT OF GEOGRAPHY

Personal Author(s) : Darby, Stephen E. ; Thorne, Colin R.

PDF Url : ADA290618

Report Date : JAN 1995

Pagination or Media Count : 81

Abstract : Existing numerical models of river channel morphology are seriously limited in their application by their inability to account for bank erosion and changing channel width. In this report, a new bank stability analysis is developed which combines the advantages of the Osman-Thorne-Darby analysis with the advantages of the Simon et al. (1991) analysis, with the aim being to improve the predictive ability of the mass-wasting algorithm and, therefore, the predictive ability of the numerical channel widening model. The new analysis is applicable to steep, cohesive, non-layered riverbanks which fail along planar failure surfaces. The analysis is developed for banks with profiles characteristic of natural, eroding riverbanks. Failure plane angles are calculated using a physically-based approach; additionally the failure plane is not constrained to pass through the toe of the bank. Pore water and hydrostatic confining pressure effects are included in the analysis. Using the procedure developed by Darby (1994), the new analysis also is capable of predicting the probability of mass failure, as well as the overall factor of safety with respect to mass failure.

Descriptors :   *MATHEMATICAL MODELS, *GEOMORPHOLOGY, *BANKS(WATERWAYS), PROBABILITY, NUMERICAL ANALYSIS, FAILURE, PLANAR STRUCTURES, PRESSURE, HYDROSTATICS, WIDTH, RIVERS, CHANNELS(WATERWAYS), GREAT BRITAIN, WATER EROSION.

Subject Categories : Hydrology, Limnology and Potamology

Distribution Statement : APPROVED FOR PUBLIC RELEASE