The Erodibility Index Method: An overview

The paper presents an overview of Annandale’s Erodibility Index Method by using a conceptual model to explain the elements of rock scour and summarizing the methodology used to quantify the relative magnitude of the erosive power of water and the relative ability of earth material to resist scour. The scour threshold relating the erosive power of water and the scour resistance of earth material is shown and the method that is used to calculate the extent of scour when using the Erodibility Index Method is explained in a conceptual manner. An approach to quantify of the relative ability of rock to resist scour is detailed in a companion paper to this volume ( Annandale 2002b ) as is the approach to quantify scour extent ( Annandale 2002c ).