Cheia de projeto: equacionando os períodos de retorno obtidos de cheia de projeto com hietogramas sintéticos a cheia de projeto obtido de chuvas observadas

• Autor(a) principal: Chimene, Catine António
• Data de Publicação: 2019
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/40446
• topic: Recursos hídricos; Hidrologia; Modelagem chuva-vazão; Precipitação (Meteorologia); Design storm; Design flood; Synthetic hyetograph; Observed hyetograph; Return period

In order to reach the objectives outlined, the return periods (RTs) of the floods obtained from precipitations observed at five-minute intervals in a historical series of 30 years collected at the meteorological station of the Center for Agricultural Sciences of the Federal University of Ceará at Campus do Pici, in Fortaleza-CE, with return periods (TR) calculated from the project floods associated to several usual synthetic grassroots for the New Sites Water catchment area. As in its origin, the rural watersheds do not have fluviometric stations, the flows are obtained from rainfall-flow models (HEC-HMS), which is adequate for each study area. Thus, the annual maximum daily rains were extracted and the flows corresponding to each series were generated later. The observed rains and flows generated rainfall and project flows where they were analyzed statistically and evaluated with Anderson-Darling adhesion tests to choose the best fit distribution functions. Rainfall and project flows were determined in different return periods (1000, 500, 200, 100 and 50 years) using the Gumbel and Log-Normal probability functions respectively for the catchment area and the reservoir respectively. The project rains were used in the standardization of different forms of rainfall distribution (different synthetic hietograms) through which the project flows were generated and compared to the other project flows obtained from the probabilistic models in the observed hietograms. All of them with projects obtained from synthetic hietograms underestimated and consequently the calculated return period. With this it was demonstrated that the standardization of rainfall in different forms of rainfall distribution was not feasible and applicable to the design of hydraulic works over 50 years of return period. In addition, the bias correction factor was calculated in all forms of rainfall, which showed the possibility of having an equality of the design flows and consequently the return periods, but with the corrected design rain in each form of rainfall distribution ( Empirical, Delayed Blocks, Alternate Blocks, Uniform with Concentration Time, Advanced Blocks and Uniform 24h). The damping of the floods presented a differentiated sequence as to the order of magnitude of their peak flows before the hydrographic basin. The results are valid for small hydrographic basins with a rainfall regime similar to that of the northern coast of Ceará and the equation of the return period presented desirable results for time under 50 years.