Description
As a final task for the life-extension program of the Embalse N.P.P. located in Córdoba, Argentina, the pre-stressed concrete Containment Structure (CS) has been subjected to a full-scale pressure-leak test after more than 30 years of service. The test was carried out at the start of the summer season, after completion of a general overhaul of main functional components; the CS had previously been inspected, and successfully passed a first evaluation before the implementation of its life extension process. This paper is concerned with the analysis of the structural response of the CS to internal pressure and comparison with test results. The purpose of the paper is focused on assessing the structural response of the CS through the measured displacements and strains caused by the prescribed pressurization sequence. Special attention is given to thermal changes caused by exposure to sun radiation and daily temperature changes over the course of almost one month duration of the test sequence. A numerical model of the CS developed for a preliminary assessment of the design requirements imposed on the CS was also used in order to filter out the associated uncontrolled thermal strains and displacements that occur simultaneously with those associated with the changes in the internal pressure. The numerical model was first used to evaluate the expected stresses and compliance with design requirements during the test, and was later used to calculate the thermally induced strains and displacements that occur during the pressure test in order to assess the displacements directly associated to the increase in internal pressure.
