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http://dx.doi.org/10.21729/ksds.2018.11.2.61

Analysis on the Scour Reduction Effect by Controlling Downflow  

Lee, Ho Jin (School of Civil Engineering. 208, E8-6, Chungbuk National University)
Oh, Hyoun Sik (School of Civil Engineering. 208, E8-6, Chungbuk National University)
Publication Information
Journal of Korean Society of Disaster and Security / v.11, no.2, 2018 , pp. 61-67 More about this Journal
Abstract
Scour protection methods can be categorized as two types: The first is to reduce the horseshoe and wake vortices which are the main reasons for local scour. Either small cylindrical structures or separated vertical deflectors can be placed in front of the pier or the horizontal deflector (or collar) can be attached to the pier like the spoiler to reduce the dynamics of vortical structures. The second is to employ the protection layer to keep the bed material in place, which is a common method with a merit of immediate effect by using block mat or tetrapod. This study examined the effect of scour reduction using the former method. The relationship between the reflector interval and reduction of scour was not clear. It is assumed that the width of the reflector is somewhat correlated with the reduction of the scour. As the KC numbers increases, the Effect of Scour reduction rate is shown to decrease. Also, Scour reduction rate showed a rapid change at $U_R=25$ or KC = 8.
Keywords
Deflector; Local scour; Scour reduction; Ursell number; KC number;
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