Prediction of scour depth at bridge abutment in compound channels

Document Type : Original Article

Authors

Abstract
Bridge failures due to scour at bridge abutments have clarified the importance of scour depth prediction. Most of bridge abutments are located in the floodplain. Also, one of the common cases in a floodplain is vegetation. Velocity and shear stress distribution in compound channels are not uniform and the obtained results from rectangular channels cannot be used for compound channels. In this study, based on experimental observations, dimensional analyses and multivariable non-linear regression, a dimensionless relationship for prediction of scour depth at vertical wall abutment terminating in the vegetated floodplain of a compound channel is suggested. The results indicated a good agreement between the experimental observations and predicted values by suggested relationship. For suggested relationship, coefficient of determination (R2) was 0.94 and root mean square error was obtained 0.79 centimeters.

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  • Receive Date 06 April 2012
  • Revise Date 17 July 2012
  • Accept Date 17 August 2012