Controling Local Scouring Around Bridge Pier using Nano-Structured Materials

Document Type : Research Paper

Authors

Assoc. Prof., Dept. of Water Eng., Faculty of Soil and Water Engin., Gorgan Univ. of Agric. Sciences and Natural Resources, Iran

Abstract

Local scour is one of the main drivers of instability and failure of bridge piers. Therefore, in addition to the stability issue, the scour depth reduction is also important. Numerous solutions have been presented for scour depth reduction. In this study, a new idea environmentally-friendly and non-structural approach has been introduced for bridge pier scour depth reduction. Nano-structured materials are waterproof, they can be used for scouring reduction in alluvial beds. For achievement of research aims, the bed sediment around the bridge pier was mixed with some nano-structured material called nanoclay. The experiments were carried out in a laboratory flume under steady conditions on a cylindrical bridge pier. The obtained results showed that, the highest scour depth reduction percentage (58.3%) occurred for the largest flow discharge (16 L s-1) by a large difference compared to other values of flow discharge. In this case, the scour depth was decreased from 60mm to 25mm due to presence of nano-structured material. The lowest percentage of scour depth reduction was nearly 41.6 for the minimum flow discharge (4 L s-1).

Keywords


 
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