Erosion and sedimentation patterns associated with restoration structures of bendway weirs

Roughness Effect of Submerged Groyne Fields with Varying Length, Groyne Distance, and Groyne Types

“…Möws and Koll [10] improved the groyne model ( Figure 1b) and investigated morphological and hydraulic effects on a single submerged groyne in a straight laboratory flume with a mobile bed. In contrast to common results e.g., [5,6,9], the main scour at the groyne head is not attached to the groyne, but located further downstream, which is related to the groyne shape. A similar scouring effect due to the groyne shape was observed by Bressan and Papanicolaou [4] for stream barbs up to a certain level of submergence and by Kadota et al [8] for permeable submerged groynes.…”

“…However, if simple structures, especially those with sharp edges, are used in morphodynamic studies, misleading conclusions may be drawn. For example, studies of morphological changes due to simplified models report distinct scouring at the head of the groynes, e.g., [6,9]. On the contrary, in mobile bed experiments carried out with more naturally shaped types of single submerged groynes, the main scour was observed downstream of the groyne head [4,8,10] and the stability of the structure was not compromised by a groyne head scour.…”

“…An overview of types and related studies is given by Radspinner et al [1] and, more recently, by Zaid [2]. Studies on ecological benefits e.g., [3], morphological effects e.g., [2,[4][5][6][7][8][9][10], and flow fields [7,[10][11][12][13][14][15] provide evidence of the structures' potential. Single structures are often used for ecological purposes only, i.e., to increase the variation of river morphology and flow diversity in river restoration projects e.g., [4,10].…”

“…For nature-orientated river training, arrangements of groynes are employed, e.g., [2,3,13]. Both single elements and groups of structures require design guidelines for the stability of the structure itself, e.g., [4][5][6]9], as well as for the specific purpose of implementation. For specific structure types, mainly stream barbs and bendway weirs, design guidelines were developed based on field experience, e.g., [16,17], numerical simulations, e.g., [11], and physical model tests, e.g., [11,13,18].…”

Hybrid Modeling for Solutions of Sediment Deposition in a Low-Land Reservoir with Multigate Sluice Structure

“…To counteract the undesired reservoir sedimentation, necessary measures are required. River training approaches are commonly used, which include construction of spur dikes [28][29][30], rock vanes, and bendway weirs [31,32], various types of revetments [33], and dredging [34]. Each approach has its advantages and limitations.…”