Abstract
In this paper, the effect of wave direction on local scour at rectangular columns was investigated. Local
scour depth around rectangular column is variable in association with the shape of column and angle of column
oriented to the direction of waves. In general, the point of maximum scour depth occurred at the comer of the
column when column width oriented 90 to the wave direction. At another angle of orientation, the point of
maximum scour depth tended to move to the cross-sectional comer perpendicular to the wave direction. As a
result, it shows clearly that the effect of wave direction on scour depth was variable in association with the
shape of column, referred to column thickness, and also the angle of orientation. The orientation factor, Kθ
which accounts for the effect of wave direction in the scour depth equation, was examined. In conclusion, the
effect of wave direction should be considered as a factor for estimating scour depth of artificial reef.
