抄録
In this paper, we investigated flow structure and bed deformation around a single spur dike downstream of a pile-group in an open channel. The purpose was to find out an optimum distance between pile-group and spur dike for reducing the local scour. For comparison, a single impermeable spur dike (conventional type) without the pile-group was also evaluated. A series of experiments under emerged flow and clear-water scour conditions were conducted. In the cases with an upstream pile-group, the local scour was faded with a noticeable decrease in the depth and amount of bed erosion. The scour depth and volume were decreased as the distance increased from zero to four times the spur dike length. Flow velocity near the nose of spur dike was higher in the conventional type spur dike. In the cases with a pile-group, flow near the spur dike became lower relative to the conventional case. But, in the main stream the flow increased as the pile-group and spur dike distance increased.
