Study On Flood Routing Characteristics Of Earth-rock Dam Break In Moutainous River

The mountainous river,restricted by terrain,is usually deep and winding,with obvious interval intersection phenomenon and complex boundary conditions in the process of dam break flood routing.As a result,floods in mountainous areas are often sudden and extremely strong,carrying rapidly and with great destructions.For the mountainous area is the natural base for dam construction,the loss will be unpredictable in the event of a dam break.Therefore,in order to prevent the occurrence of dam break accidents,it is very important to accurately grasp the evolution characteristics of dam break flood and reasonably calculate the evolution process of dam break flood,which can guide people to take effective measures in advance and reduce the flood disaster to the greatest extent.In view of this,HEC-RAS software is used in this paper to establish a numerical calculation model of dam-break flood.According to different river conditions and dam-break conditions,the evolution of dam-break flood is simulated and its influence on the evolution process of dam-break flood is analyzed.The main research contents and achievements are as follows:(1)Through the establishment of a simplified rectangular river model to simulate the flood evolution process after earth-rock dam failure,the influence of different river conditions and different breach conditions on the flood routing of dam-break is compared and analyzed,and the influence of different river conditions different breach conditions on the flood routing characteristic parameters is obtained.(2)Based on Gaodongzi Reservoir in Banan District of Chongqing,a two-dimensional model of dam-break flood routing of Gaodongzi Reservoir was established,and the influence of reservoir inflow flood and interval catchment on dam-break flood routing process under different frequencies is calculated and analyzed.(3)According to the calculation results,the most unfavorable scheme was analyzed,and the ArcGIS technology was used to show the evolution process of dam-break flood under the scheme,and a preliminary emergency transfer scheme was developed for the villages and towns along the downstream of the dam.(4)The calculation schemes are analyzed rationally,and the results show that the model is reasonable and scientific to a certain extent,and can better reflect the evolution of dam break flood.