2134/32283 Ana Blanco-Alvarez Ana Blanco-Alvarez Sergio Pialarissi-Cavalaro Sergio Pialarissi-Cavalaro Ignacio Segura Ignacio Segura Luis Segura-Castillo Luis Segura-Castillo Antonio Aguado Antonio Aguado Expansions with different origins in a concrete dam with bridge over spillway Loughborough University 2018 Gravity dam Expansions Alkali-silica reaction Delayed ettringite formation Modelling Built Environment and Design not elsewhere classified 2018-03-20 12:04:35 Journal contribution https://repository.lboro.ac.uk/articles/journal_contribution/Expansions_with_different_origins_in_a_concrete_dam_with_bridge_over_spillway/9447140 Concrete dams with expansions from different origins are rare and scarcely documented in the literature, therefore their study gains special interest. This study presents the case of a 62-year-old concrete dam with signs of deterioration due to expansive reactions. Several tests performed on the samples extracted from the dam such as X-ray diffraction, scanning electron microscope with energy dispersive spectroscopy mode and petrography suggest that the expansions are due to a delayed ettringite formation and a subsequent alkali-silica reaction. Thermal and mechanical models developed in the study support this diagnosis.