Abstract
Exerimental study was performed on flow pattern on alternate bars, including supercritical flow and subcritical flow, and its influence on bank erosion. It is shown that the flow patterns are classified into four patterns. Type A: flow with both of supercritical and subcritical flow which is directed to side wall due to sand bar effect. Type B: flow with both of supercritical and subcritical flow which is directed to downstream along the straight river. Type C: transision between type B and type D. Type D: flow with only subcritical flow. Characteristics of these four flow patterns were clarified by the flow field measurement. And it is concluded that bank erosion intensity is closely related to these flow patterns.
