On the hydraulic and environmental functions of flood defense woods.

防洪林的水力与环境功能研究.

基本信息

批准号：
07455197
负责人：
FUKUOKA Shoji
金额：
$ 5.12万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455197/
关键词：
flood defense woods meandering phase sift groin cut flood control flood channel main channel 蛇行流路洪水流水面変動河床変動

项目摘要

The flood defense woods were planted and has been preserved because the house and the field along the riverside are defended from the flood damage. Recently, because the tree clusters in the river channel cause the resistance of flows, The flood defense woods was deforested for the flood control. To maintain an excellent river environment, the effect on the leaving method and the flood control of the woods was examined. The effect of the trees changes depending on the arrangement of the tree clusters to the shape of the river channel, depth on the flood channel, and the velocity of the flow in the main channel. The bed topography of river changes due to the flow which is influenced by flood defense woods. A plane structure of the flow between a flood channel and the main channel was clarified in this research. The exchange of the current is caused between the flood channel and the main channel in a compound meandering channel. In addition, flood flow are controlled by the flood control woods along river bank. A numerical model by which such flow fields were able to be explained enough was developed. It was shown to be able to analyze the flow of the compound meandering channel seen in the actual river by using this model. If the flood defense woods are deforested, high velocity is caused in that part. As a result, it has been understood that the flood control woods around damaged part may be lost due to flow if the part where were damaged is covered by a bank protection made of blocks. On the other hand, when a part of the flood defense woods was deforested, the flow velocity of the rive bank neighborhood is decreased and the secondary current in the outer bank are weaken. It is shown that there is a necessity for evaluating the value of the flood defense woods overall including such an effect of the flood control in the future.

洪水防御林被种植并保留了，因为河滨沿岸的房屋和田野免受洪水的损害。最近，由于河道中的树簇引起了流动的阻力，因此防洪林被森林防卫进行了洪水控制。为了维持良好的河流环境，检查了对离开方法和森林防洪的影响。树木的效果根据树簇的排列而变化，取决于河道的形状，洪水通道上的深度以及主通道中流动的速度。河床的形态变化是由于洪水防御林影响的流动而变化。在这项研究中，阐明了洪水通道和主要通道之间流动的平面结构。电流的交换是在复合蜿蜒通道中洪水通道和主通道之间引起的。此外，洪水流由河岸沿河的防洪林控制。一个数值模型可以通过该模型来解释这种流场。事实证明，它能够通过使用该模型来分析实际河中看到的化合物蜿蜒通道的流动。如果防洪林被森林砍伐，那部分就会造成高速。结果，据了解，如果被损坏的部分覆盖在损坏的零件被块制成的银行保护覆盖的零件覆盖的情况下，可能会因流量而丢失洪水控制木材。另一方面，当洪水防御森林的一部分被砍伐森林时，Rive Bank社区的流速下降，外岸的次级电流减弱。结果表明，有必要评估整体防洪林的价值，包括未来洪水控制的影响。