Failure analysis of reinforced concrete elevated storage tanks

Assessing the condition of existing structures, with a particular focus on analysing the degradation level, is a complex issue for those responsible for maintenance and monitoring. Elevated storage tanks (water towers) are particularly prone to suffering obsolescence and degradation. As many of these structures are no longer in use and in a poor state of conservation, researchers and local administrators need new tools to achieve a complete overview of the tank condition on a regional scale with limited resources. This paper presents a large-scale structural degradation analysis on the specific structural typology of storage tanks. Firstly, the tanks performances and degradation level are analysed by using a multicriteria approach useful to include both qualitative and quantitative data in the analysis. Secondly, 32 case studies in Valencia (Spain) are investigated to demonstrate the method's potential. Thirdly, the results of the degradation analysis were used to identify the most frequent damage, the related causes and the structures in the worst conditions. Finally, the best maintenance and intervention strategies to extend the tanks’ remaining life and protect them from further damage are proposed.