عنوان مقاله [English]
Beach-bound plates are used to control the erosion of the walls of rivers and beaches. The nose of the plates has always been subject to scour due to the flow contact with the structure. Different factors are effective in reducing the scour. Recent research has shown that coastal and beach-bound triangular slotted panels have played an important role in reducing the scour around the nose. In this study, in order to investigate the effect of the angle, the triangular slab (slit area = 10% of the effective surface area of the plate) was used at different angles of (23, 30, 40 and 60 degrees) in arched flume. Experiments were conducted under different hydraulic conditions (landing numbers 287/0, 304/0 and 322/0). The results showed that the maximum scour depth at the 23 and 40-degree angles was the lowest and the highest, respectively. The maximum stacking height is proportional to the maximum scour depth. By increasing of the angle of the plates up to 40 degrees, the maximum scour depth is farther away from the outer curve and drops sharply at an angle of 60 degrees.
One of the issues in river engineering is erosion in the walls of rivers and coasts, due to the direct connection of the flow with the wall. The pattern of velocity distribution in the arc indicates the concentration of areas with maximum velocity in the lower arch and in the vicinity of the outer wall. Spoons are considered as protective structures that are used to reduce the erosion and improve the stabilization of the riverside wall. But, on the other hand, the location of the spillway in the flow path and the direct impact of the flow on the structure leads to local scouring around the nose of the spillway and, as a result, will eventually destroy the structure. It is noteworthy that the coastal triangular board of the modified state of the protective structures (in terms of appearance, degree of submergence, There is a gap in the page) for A. Judd minimum depth of scour around the nose page. . In a study by Boyan et al. (2010), in a single-seater survey of coastal triangles, the effective method for restoring river banks is to install these panels at low angles (20 and 30 degrees) and in the coastline. Therefore, due to the limited research done on the beach-bound plates, in a leading research with the installation of single-skeletal triangles attached to the coast at different angles, the angles of their placement on the topography of the bed in the 90-degree arc have been studied.