Author(s): M. Sc. Civil Engineer Zivko Gencel
Linked Author(s): Zivko Gencel
Keywords: Mountains river regulation works; Deflector type protection structure; Slightly curved partly cylindrical surface on the bank slope; Wildlife habitat zones
Abstract: The mountains river regulation works (concave bank protection) should be adaptable to bottom erosion as much as resistant to the abrasion effects of floods heavily charged by sediments in suspension and by bed load. The problem solution complicates more when the watercourse bottom width is of limited size and/or when the longitudinal bottom slope is to high. Generally, in such circumstances and considering alluvial environment, the breakwater structures should be replaced by continuous bank protection equipped with deep foundations which results the most expensive alternative. The article offers preliminary arguments about a specific kind of solution analyzed by means of physical and mathematical hydraulic model research with satisfying results. This new structure consists of short rock deflector linings which creates slightly curved, partly cylindrical surface on the bank slope, being the radius of its curvature much smaller than the one of the river curve. These structures could be placed at regular distances along the concave bank to be protected in very similar way as if they were breakwater structures. In front of each of them the bottom is covered by apron (rip-rap) adaptable to the river bottom general erosion. The main advantage of this structure is it′s adaptability to the strong bottom erosion as well as to the abrasion without excessive invasion of the bed width. Downstream of these structures and close to the bank to be protected are formed zones of shadow – vorticity with flow velocities low enough as to guarantee bank stability. Therefore they can be considered also as suitable for corresponding wildlife habitat.
Year: 2009