Um estudo de pressões intersticiais da Barragem de Corumana

Abstract

Pore pressures are fundamental to the stability of earth dams, being intrinsically linked to critical phenomena such as internal erosion, piping, and slope instability. The absence of effective monitoring severely limits the ability to detect early-stage failure mechanisms, thereby compromising the implementation of preventive measures. Given the strategic importance of the Corumana Dam in water resource management in Mozambique, this study was conducted to deepen the understanding of risks associated with pore pressures and propose measures to enhance the structural safety and functionality of the dam. To achieve this objective, piezometric data were collected and analyzed to investigate underground seepage conditions, hydraulic gradients in the dam’s foundation, the influence of factors such as reservoir levels on pore pressures along the dam, and slope stability under different operational scenarios. The results showed that 70% of the piezometers exhibited a strong correlation with reservoir levels, with pressures exceeding expectations recorded at PTA 18. The maximum hydraulic gradients remained within safe limits, no anomalies were detected in seepage flow rates, and the slope stability factors exceeded the minimum recommended values. However, the current monitoring system, characterized by low reading frequency and lack of automation, hinders the early detection of potential failure indicators.