Water Department, Shiraz University, Shiraz, Iran.
Environ Monit Assess. 2010 Dec;171(1-4):621-31. doi: 10.1007/s10661-010-1306-x. Epub 2010 Feb 20.
River bed scourings are a major environmental problem for fish and aquatic habitat resources. In this study, to prevent river bed and banks from scouring, different types of bed sills including convex, concave and linear patterns were installed in a movable channel bed in a laboratory flume. The bed sills were tested with nine different arrangements and under different flow conditions. To find the most effective bed sill pattern, the scouring depth was measured downstream of the bed sill for a long experimental duration. The scour depth was measured at the middle and at the end of each experimental test for different ratios of the arch radius to the channel width [r/w]. The experimental results indicated that the convex pattern with r/w=0.35 produced minimum bed scouring depth at the center line whereas the concave pattern with r/w=0.23 produced the minimum scour depth at the wall banks. Therefore, the convex pattern was the most effective configuration for prevention of scouring at the center line of the river while the concave pattern was very effective to prevent scouring at the river banks. These findings can be suggested to be used in practical applications.
河床冲刷是鱼类和水生栖息地资源的一个主要环境问题。在这项研究中，为了防止河床和河岸冲刷，在实验室水槽中的可移动河床中安装了不同类型的床槛，包括凸形、凹形和线性图案。对床槛进行了九种不同布置和不同水流条件下的测试。为了找到最有效的床槛图案，在床槛下游进行了长时间的冲刷深度测量实验。在每个实验测试的中间和末尾测量了冲刷深度，以不同的拱半径与通道宽度的比值[r/w]为标准。实验结果表明，在中心线处，r/w=0.35 的凸形图案产生的冲刷深度最小，而 r/w=0.23 的凹形图案在河岸处产生的冲刷深度最小。因此，凸形图案是防止河流中心线冲刷的最有效配置，而凹形图案则非常有效地防止河岸冲刷。这些发现可建议用于实际应用。
