Análise da percolação de água na barragem de terra do Realejo – CE

Abstract

This study aims to analyze water seepage in the earth dam of the Realejo district, located in the municipality of Crateús-CE, to assess potential areas at risk of internal erosion (piping) and the adequacy of the existing drainage system. For this purpose, numerical simulations were performed using the finite element method (FEM) with the SEEP/W software from GeoSlope. The analyzed dam is of the homogeneous type, predominantly composed of silty clay, and features a drainage system consisting of an inclined filter, drainage blanket, and toe drain. The results showed that, in the absence of these elements, the seepage rate in the dam body reaches 4.1 × 10⁻⁴ m³/s, indicating a high risk of uncontrolled percolation and potential erosive processes that could compromise the dam's structural stability. With the presence of the filters, the seepage rate was reduced to 1.39 × 10⁻⁵ m³/s, representing an approximate 96.5% reduction, confirming the efficiency of the drainage system in mitigating risks. In addition to the current configuration, alternative arrangements with different filter placements were tested, with the combination of a vertical filter, drainage blanket, and toe drain yielding the best results.With the testing of alternative filter sets, it was identified that the system currently implemented in the reservoir is the most efficient. Based on the results obtained, it is concluded that seepage analysis is essential to ensure reservoir safety, prevent structural failures, and mitigate environmental impacts. The use of computational tools, such as SEEP/W, proved to be crucial in understanding water flow behavior and aiding decision-making for the maintenance and improvement of local hydraulic structures.