Risk Analysis On Flood Discharge Concerning The Uncertainty Of Flood Hydrograph

In this paper, those uncertain factors affecting the flood discharge are discussed, especially the uncertainty of flood hydrograph. In the past years, people generally considered that the effect of the uncertainty of the flood hydrograph is not the main reason that result in the flood discharge risk and even ignore its effect. In the paper, this factor is take into account during analyzing and calculating flood discharge risk. A flood peak cut coefficient () is proposed to measure the affection of the flood hydrograph for the risk calculating of the flood discharge. Through the test of hypothesis it is proved that the probability distribution of is extreme-â…  type while a project in Xinjiang is took for an example of the flood discharge risk calculation. By Monte-Carlo Method the flood discharge risk is calculated with consideration of the uncertainty of flood hydrograph, and the result is compared with that without consideration of the uncertainty of flood hydrograph. It is clear that the flood discharge risk is lower when the uncertainty of flood hydrograph is considered. So the uncertainty of flood hydrograph is really a important factor which contributes to the risk of flood discharge. For practical usage, C programs are written for dealing with so much data.