Hrvatske vode, Vol. 27 No. 107, 2019.
Professional paper
Arch-shaped sills
Goran Gjetvaj
; Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
Antonija Cikojević
; Faculty of Civil Engineering, University of Zagreb, Zagreb, Croatia
Filip Ferenčak
; Hidrokonzalt projektiranje, d.o.o., Zagreb, Croatia
Josip Husajina
; Elektroprojekt, d.o.o., Zagreb, Croatia
Abstract
Sills are often constructed as part of the regulation of natural watercourses to reduce hydraulic erosion that causes riverbed deepening and thus also the lowering of surface and ground water levels. Riprap sills constructed vertically in relation to the direction of the water flow are aesthetically acceptable; however, they tend to collapse in high discharge conditions. The experiences with sill collapses on the Sava River at Zagreb and Ljubljana initiated research geared at finding a layout sill shape that is more resilient to hydraulic erosion. The paper presents a stability-related comparison between straight and arch-shaped riprap sills. The measurements were conducted on the constructed physical models with a primary goal to assess the impact of a layout sill shape on the stability. During the comparison between the two sill types (straight and arch-shaped), in the same hydraulic conditions, the number of particles washed away and the time needed for structure collapse were measured. The paper analyses the dominant forces affecting the particles and the impact of particle adhesion for arch-shaped sills.
Keywords
bed sill; arch-shaped; watercourse
Hrčak ID:
219892
URI
Publication date:
8.4.2019.
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