Analysis and interpretation of the structural behaviour of Daivões dam during the first filling of the reservoir

Abstract

This paper describes the main characteristics of Daivões dam and the construction period, presents the most relevant monitoring data and the structural behaviour interpretation of Daivões dam during the reservoir’s first filling, between October 2020 and March 2022. The safety control and the interpretation of the dam’s behaviour are based on: contraction joint movements, measured in jointmeters; planimetric (radial and tangential) displacements, measured through plumbline and geodetic methods; vertical displacements, measured through geometric levelling; rock mass foundation displacements, measured with rod extensometers; seepage and leakage measured through the drainage system; uplift pressure in the rock mass foundation, measured in piezometers; and temperatures and strains in the dam’s body measured with embedded electrical resistance devices. A three-dimensional finite element model was developed for the numerical simulation of the dam structural behaviour during the first filling of the reservoir. The hydrostatic load and the measured temperature in the dam’s body were considered in the model. The dam’s concrete delayed behaviour was assumed to be represented by the Bažant e Panula’s basic creep function, evaluated from laboratory tests.