The Study On The Model Of Flood Frequency Combination And Application To Engineering

"Design flood" means the flood of various design standards that are prescribed in the course of the planning, designing and construction of the hydraulic and hydroelectric engineering. The problem of analyzing, calculating and designing rationally of the design flood takes the first place. Since the establishment of our country, the design flood in standards and computational methods has gone through gradually from data addition of historic flood to frequency basic method, and experienced the developing course of introducing the probable maximum flood since 70s. As being influenced by the activities of human beings, the composition of region of design flood has been more and more taken notice of.This paper is to analyze and calculate the regularity of the composition of region in flood, on referring to the scientific study on Ju River and Zhang River. Zhang River Reservoir is composed by Guanyinsi and Jigongjian Reservoirs which are connected by free channel. It is concerned with two sources of coming-in flood and as far as preventing flood downstream is concerned with the composition of the flood of Ju River and the interval which are from the dam site of reservoir to two-entrance. The main investigative contents of this paper are as follows:Chapter One focuses on the present situation of studies on design flood at home and abroad, the contents of what this paper goes into and its significant meaning.Chapter Two gives the introduction of the general situation of basin, engineering and irrigation area of the Ju river and Zhang River Reservoirs, relating to the experimental reservoirs of State Flood Control and Drought Relief Headquarters.Chapter three , on the basis of principles of selected typical flood, is to select the course of typical flood and ascertain the design flood of Houziyan station, Zhang River Reservoir and Herong station and related intervals basing on the flood peak of Houziyan station and the information of its flood volume.Chapter four is to analyze and study the theory of flood frequency combination, and takes respectively the study of the methods of analyzing and calculating on built-up frequencyof the upstream, intervals of mutually independent and integrated parts.Chapter five is to talk about several methods of calculating on the composition of region of design flood. That is analyzing the composition of region of design flood on the consideration that the upstream and the downstream are of the same frequency and so are the upstream and the intervals.Chapter six, by way of selecting the 29 floods of Herong station, Yuan'an station, Zhang River Reservoir and the corresponding intervals and employing the theory of correlation analysis, is to analyze and calculate the regularity of composition of region of practical flood, and also by means of the methods of F-verification as well as T-verification to test the regression equation and correlation coefficient.Chapter seven is the conclusion and prospects into the future and makes explanation on the creative points of this paper and the main aspects that is to be studied in the following time.To ensure the safety of the reservoir and the downstream protected zone, it is essential to make studies on the composition of region of the flood, so that we can provide the basis of design for flood prevention, cross peak and safe dispatching.