Numerical Simulation Study Of Dam-Break Flood In Ma’anshan Reservoir

The Ma’anshan Reservoir in Yongshun County,the research object selected in this paper,was built in 1984 and completed and put into operation in 1989.During the operation,unsafe factors such as dam leakage,flooded factory buildings,and cracks in the dam piers have occurred.Now it provides a decision-making basis for Yongshun County’s defense against super-standard floods.Based on the MIKE model,the water flow movement of the Ma’anshan Reservoir dam failure is simulated,calculated and analyzed.The specific methods are as follows:use MIKE 11 combined with Dambreak module to establish a one-dimensional dam break model of Mengdong River,and calculate and obtain the flow process of the break;use MIKE21 to establish a two-dimensional hydrodynamic model from the dam of the Maanshan Reservoir to the Conch Hydropower Station,and obtain the dam break flood in Yongshun territory.Evolutionary flood characteristics;use arcgis to integrate Ma’anshan dam break flood with satellite maps,and finally draw a flood control transfer plan based on the inundation information of the dam break flood on the map.main conclusion:(1)Based on the existing hydrological data,the Pearson p-Ⅲ frequency fitting is carried out,and the typical flood hydrograph is scaled by using the same frequency control to obtain the inflow flood process of Ma’anshan reservoir with 50,100,200 and 500 year return periods.(2)Based on the engineering characteristics of the reservoir,seven different dam break conditions are proposed,and the maximum dam break flow and its change process under seven dam break conditions are calculated by MIKE 11 model.After the dam break,the flow of the breach quickly reaches the peak value,and then gradually decreases,and finally remains basically the same as the inflow flood.(3)From the seven dam break conditions,the flow processes of the four most unfavorable schemes are selected as the upper boundary of Mike21 model,and the dam break flood characteristics such as the maximum submerged depth,the maximum water level and flow of the dam break flood in Lianpeng,Ma’anshan,hajia village,shaoha Township,Yongshun County and other key residents along the way under different dam break conditions are obtained.(4)According to the calculation results of MIKE11 and Mike21 models,in order to ensure the safety of the lives and property of the downstream people,the emergency flood control transfer scheme and emergency response process procedure for the flooded area are formulated.