Failure similarity of gravity dam under downstream contacting blast loading

Abstract

The analysis of the blast resistance and dynamic responses of gravity dams under extreme loading conditions is crucial in ensuring the safety of hydraulic engineering structures. Recent international conflicts have further emphasized the importance of research in this field. However, the lack of quantitative experimental studies and analysis methods for assessing prototype dam damage has posed significant challenges. To address this gap, experiments and numerical simulations on scaled concrete models were conducted, considering two equivalent detonation loads and four scaling ratios. Utilizing a non-dimensional approach, comprehensive comparisons of the dam's initial fracture locations, fracture paths, and extent of damage were performed, thus leading to the identification of consistent damage patterns and similarities between the different scaled models. The results demonstrated that the primary failure mode caused by the detonation loads on the downstream face was the overall fracture of the dam crest, with a slight downward shift in the initial crack position as the detonation load increased. Remarkably, the fracture paths exhibited satisfying similarities across the different scaling ratios. Furthermore, through further discussion on topics such as the initial fracture locations and the influence of reservoir water, both theoretical and practical insights were obtained for investigating the damage of prototype dams based on similarity laws.