Abstract: Based on the combination of observed data analysis and physical model experiment,the cumulative impact of river construction projects on flood control was studied by discussion on the Shiyezhou reach in the Yangtze River.The data of river water level in nearly two decades were used to analyse the changes of different periods with the same observatory station and same flow discharge.The result of observed data analysis is similar to the one of physical model experiment,and their quantitive results about the ...