| This article has been：Browse 1181Times Download 2998Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.2021325 |
|
| Flooding Analysis for Alluvial River Based on the Balance between Flood Control and Floodplain Development |
|
XUE Hai, LIU Zhen, LIU Mingxiao, et al
|
|
North China University of Water Resources and Electric Power,
Port Channel and Ocean Development Research Center, Zhengzhou 450046, China
|
| Abstract: |
| 【Background】Floodplain is the ecological cradle of alluvial rive to provide a buffer to flooding. Rivers naturally function to transport runoff and sediment, making the river have the double section characteristics of river trough and beach to meet the needs of water and sediment transportation in different periods. There are also villages in the floodplain of many rivers. There will inevitably be some contradictions between the needs of human activities (such as agricultural irrigation, transportation and social development) and river functions (ecology, flood and sediment transportation). If there is no scientific coordination between the two aspects, it will lead to mutual restriction affecting the ecological health of the river as well as the Sustainable high-quality development of the beach area society. It has become an important challenge for river managers to plan traffic routes in wide floodplain areas with less environmental impact. In order to implement the protection of river health in river project construction, the characteristics of alluvial river flood must be understood under the influence of human activity.【Objective】Taking advantage of the vast river floodplain to conduct the appropriate development and construction, it would be helpful to promote the high-quality development of the river basin. Learning more about the flood characteristics of alluvial rivers under the influence of human activities, and proposing a solution scheme to realize the coordination of floodplain engineering construction and river safety flood discharge, would contribute to practicing the protection of river health in constructing the river engineering.【Method】Taking a proposed eco-tourism greenway in the wide floodplain area of an alluvial river as an example, using the comprehensive research method involving historical evolution analysis, riverbed scouring-depositing prediction and hydrodynamic numerical simulation, the flood characteristics of the engineering reach, the law of river course evolution, the riverbed adjustment factors at the lower reaches of the reservoir were analyzed. The treatment model for predicting the riverbed boundary and the equivalent resistance of the river engineering were studied. By means of two-dimensional flood numerical simulation, the flood characteristics of the river section involved in the greenway and the influence of the route on the flow field during the flood discharge period were also analyzed.【Result】Firstly, the simulation shows the free swing of the mainstream is restricted by the regulation projects, and the river regime in flood period remains unchanged. Secondly, the proposed greenway is far away from the main channel and the routing is in parallel with the channel, which make the water blocking ratio of the flow area in the beach area less than 2.6%, and the local backwater caused by road construction limited to 0.058 m.【Conclusion】The arrangement of the proposed greenway is suggested to be routed along the river and located in high beach. Through scientific planning of routes and project layout, the impact of the project on the propagation of river floods can be minimized, and the coordinated relationship between the river flood discharge safety and the beach area development can be satisfied. |
| Key words: alluvial river; floodplain development; hydrodynamic simulation; flood discharging safety; water resistance ratio |
|
|
