Analysis of the effect of regional lateral inflow on the flood peak of the Three Gorges Reservoir  

作　　者：WANG BaiWei TIAN FuQiang HU HePing 

机构地区：[1]State Key Laboratory of Hydroscience and Engineering,Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Science China(Technological Sciences)》2011年第4期914-923,共10页中国科学（技术科学英文版）

基　　金：supported by the National Basic Research Program of China ("115" Program) (Grant No. 2008BAB29B09);the National Natural Science Foundation of China (Grant No. 50823005)

摘　　要：The Three Gorges Region(TGR),located at the lower reach of the Upper Yangtze River Basin(UYRB) in China,suffers from heavy rainstorm frequently.The runoff generated from TGR composes an important part of the total flood at the famous Three Gorges Reservoir(TGRe).During the severe flood period in 1954,for example,the water from TGR accounted for up to 13.2% of the 30-days maximum flood volume of the UYRB.Considering the short and steep tributaries with rapid concentration,the regional lateral inflow(RLI) may induce more serious effect on the flood peak of the TGRe than the volume.However,hydrological data of the sparse gauge stations is too insufficient to evaluate the effect of RLI.This paper studied the impact by analyzing 880 flood events during 1956-2000.By comparing the observed hydrograph and simulated hydrograph with HEC-RAS software regarding no RLI,the effect of RLI on flood peak value and timing properties was identified and quantified.The variability of this effect among floods of different magnitudes was also analyzed.To evaluate the analysis uncertainty associated with the parameter of roughness coefficient,four sets of roughness coefficients from different research groups were employed in this study.The results showed that RLI contributes discharge of 3524 m3/s to flood peaks of the TGRe on average,with the contribution ratio of 15.9%.RLI contributes 12000 m3/s to the flood peaks larger than 50000 m3/s on average,with 25000 m3/s as its upper bound,while the contribution ratio can reach up to 50%,with an average of 20%.The variability of this effect is great among different events.Statistical analysis showed that to larger flood peak of the TGRe,RLI contributes more discharge with higher variability,and the contribution ratio and its variability are slightly larger,and events with higher contribution ratio occur more frequently.RLI can reshape the hydrograph,leading to earlier appearance of flood peak.This effect and its variability increase with the contribution ratio.This study has revealed that RLI

关 键 词：regional lateral inflow flood peak flood peak time HEC-RAS the Three Gorges 

分 类 号：TV145[水利工程—水力学及河流动力学] TU991.35[建筑科学—市政工程]