Analysis and interpretation of the structural behavior of Covão do Meio dam, affected by concrete swelling, considering concrete visco-elasticity and cracking

Abstract

This paper presents an updating of the analysis and interpretation of the structural behavior of Covão do Meio dam (in Portugal) which concrete is affected by an ongoing swelling process. The simulation of dam’s behavior over time is based on mathematical modelling, considering a three-dimensional representation of the structure and of its rock mass foundation, solved by the finite element method. All relevant actions are considered, namely the dead weight of the materials, the hydrostatic pressure on the upstream face, the temperature changes in the dam’s body and the concrete expansions of internal origin. The computing of the swelling action considers the influence of the temperature and of the stress fields. The structural model considers the concrete viscoelastic behavior and the cracking phenomena. The main monitoring quantities and the corresponding numerical results, including the cracking patterns, show a good agreement, attesting the adequacy of the models used to simulate dam’s behavior over time.