Comparação das vazões de projeto pelo método racional e método tempo área para bacias urbanas do município de Goiânia – Go

Abstract

The inefficiency of some devices and undersizing urban drainage accurately reflect the lack of studies, regarding the design flows resulting from rainfall. This work results from a comparative analysis of two methods for determining the flow of design in urban and rural basins. The study was carried out on three basins in the city of Goiânia ‐ GO with different values of drainage area (Ruivinho, Mingau e da Cruz). With data from the physical characteristics of the basin was used a simulation method that yielded the design rainfall for different return periods for sections outfall. We then employed the rational methods and time‐area to determine the design flow. The values found for the rational method have not varied for the basins in question, one can say that the difference was insignificant. This study demonstrates that the rational method tends to overestimate the flows of the project and should not be used for basins exceeding 1 km2 for not considering the translation in the basin and the way of it.