Development of design criteria for increasing the discharge capacity in concrete dams using spillways with highly-converging chutes.

The ALCON project pursues the definition of general criteria for the design of spillways with highly-converging chutes. These spillways, located over the body of concrete dams, are characterised for having much more width at the crest of the dam than at the entrance of the stilling basin, and for counting with a pair of converging chutes or channels that consequently conduct the water over the dam face. This configuration permits an important increase in the discharge capacity, which is a topic of interest in the most recent dam safety guidelines.

Regarding the generation of hydroelectric energy, this typology allows the maximization of the reservoir storage capacity (increase of the maximum operation level) as a consequence of the reduction in the hydraulic head over the spillway crest that this typology permits for any given design flood.

This project combines physical and numerical models, which interact in a feedback process. Initially, computational models support the design of the hydraulic model and ease to the fixation of a test campaign. Once started, the tests serve as the reference for the calibration and optimization of the numerical models. When the numerical method is calibrated and validated, it is used to provide a generalisation of the results, as they permit much more dense measuring and the introduction of more variations in the problem parameters. The final objective is the establishment of design criteria for the project of this kind of spillways.



This R&D project has been funded by: