在湍流中游泳的鱼
Low-level river crossings, including culverts, are important for delivering a range of valuable socioeconomic services, including transportation and hydrological control. These structures are also known to have negative impacts on freshwater river system morphology and ecology, including the blockage of upstream fish passage, particularly small-body-mass fish species. Given the enormous environmental problems created by road crossings, new hydraulic engineering guidelines are proposed for fish-friendly multi-cell box culvert designs. The focus of these guidelines is on smooth box culverts without appurtenance, with a novel approach based upon three basic concepts: (I) the culvert design is optimized for fish passage for small to medium water discharges, and for flood capacity for larger discharges, (II) low-velocity zones are provided along the wetted perimeter in the culvert barrel, and quantified in terms of a fraction of the wetted flow area where the local longitudinal velocity is less than a characteristic fish speed linked to swimming performances of targeted fish species, and (III) the culvert barrel is smooth, without any other form of boundary treatment and appurtenance. The present monograph develops a number of practical considerations, in particular relevant to box culvert operations for less-than-design discharges. It is argued that upstream fish passage capabilities would imply a revised approach to maintenance, in part linked to the targeted fish species.
中文| 2021 |第203页|国际标准图书编号：036754606X，0367465736| PDF | 18.0 mb低水位河流穿越，包括涵洞，对于提供一系列有价值的社会经济服务，包括交通和水文控制，非常重要。众所周知，这些结构对淡水河流系统的形态和生态也有负面影响，包括堵塞上游鱼类通道，特别是体型较小的鱼类。鉴于道路交叉口造成的巨大环境问题，为鱼类友好型多室箱涵设计提出了新的水利工程指南。这些指南的重点是无附属物的光滑箱涵，采用了一种基于三个基本概念的新方法：（I）涵洞设计针对中小型排水的鱼类通道和较大排水的洪水容量进行了优化，（II）涵洞洞身沿湿周设置了低速区，并根据局部纵向速度小于与目标鱼类游泳性能相关的特征鱼类速度的湿流面积的一部分进行了量化，以及（III）涵洞身是光滑的，没有任何其他形式的边界处理和附属物。本专著提出了一些实际考虑因素，特别是与低于设计流量的箱涵操作相关的考虑因素。有人认为，上游鱼类通道能力意味着需要修改维护方法，部分与目标鱼类有关。本站不对文件进行储存，仅提供文件链接，请自行下载，本站不对文件内容负责，请自行判断文件是否安全，如发现文件有侵权行为，请联系管理员删除。
Flux - Jinwoo Chong
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