SEGURANÇA CONTRA O RISCO DE PIPING EM BARRAGENS DE TERRA ATRAVÉS DA DISTRIBUIÇÃO WEIBULL

Abstract

One of the relevant problems in Dam Safety is the phenomenon of internal erosion, piping. Understanding the characteristics that involve this phenomenon to analyze its probability of occurrence, collected the Annual Dam Safety Reports (RASB), from 2006 to 2019, evaluating the anomalies present in the massifs of 82 dams of the state of Ceará, so that it indicates a state of conservation related to the characteristics of the piping. The evolution of piping was analyzed, translated by the state of conservation, through a probabilistic model, to measure the risk of dam rupture in a predetermined time, using the Weibull distribution. The analysis considered, as important characteristics in the piping evolution, the age of the dam, the type of soil present in the massif, and the level of water in the reservoirs during the study period. The sample collected was stratified into three groups separated by age of the dam and one group for dams with a more critical state of conservation. Parameters applicable to the Weibull distribution were estimated using the Maximum Likelihood estimator, allowing to quantify the risk that the dams in Ceará have to develop the piping anomaly, accounting for 10 dams with a Piping Risk greater than 75%.