Groyne

About: Groyne is a research topic. Over the lifetime, 397 publications have been published within this topic receiving 4549 citations. The topic is also known as: groin & Breakwater.

Flow Details near River Groynes: Experimental Investigation

Abstract: Experiments have been carried out in a fixed-bed flume for a schematized straight river reach with groynes on one side to study the dynamics of the flow near groynes. The flume had a geometrical scale of 1:40, based on typical dimensions of the Dutch River Waal. Both emergent and submerged groynes were studied. The measurements demonstrate the differences in the nature of the turbulence between submerged and emerged groynes stages; and provide insight into the flow pattern in the vicinity of groynes, the shape and the extent of the mixing layer at different flow stages, and the dynamic behavior of the velocity along the mixing layer between the main channel and the groyne fields. A parameterization of the turbulence characteristics of the flow near groynes is presented. Large-scale velocity fluctuations are found in all test cases, with timescales that vary with the flow stage. The large-scale u and v velocity fluctuations are in phase in the center of the mixing layer and out of phase for the points on the boundaries of the mixing layer.

Erosion near groyne-like structures

Abstract: This paper presents the results of an exploratory study on the development of clear-water scour near a simple groyne-like structure. The growth of the maximum depth of scour with time has been found to be similar. Further, the characteristics of the scour hole in the end state have also been found to be similar. Some simple correlations have also been developed for predicting the maximum depth of clear-water scour in the end state for a narrow range of the relative width parameter.

Habitat modification in a dynamic environment : The influence of a small artificial groyne on macrofaunal assemblages of a sandy beach

Abstract: Coastal armouring is the primary method used to combat beach erosion worldwide, and its use is likely to increase in response to accelerated coastal retreat and erosion caused by rising sea levels and storms. Yet, the ecological effects of coastal armouring structures are poorly understood, particularly for macrobenthic communities. We therefore quantified the effects of a small perpendicular groyne on the physical characteristics of a sandy beach and documented the consequences for the structure of macrobenthic communities on the beach intersected by the groyne. The groyne altered the dynamics of the physical environment, creating depositional conditions on one side of the structure, while causing some erosion on the opposite side. Changes in physical properties translated into marked spatial variations in macrofaunal diversity, abundance and species composition: ecological effects were strongest within 15 m of the groyne wall. Given that coastal armouring will become more widespread, environmentally sustainable beach management will need to encompass the ecological consequences of altering beach habitats via structural engineering interventions.