Effect of Contraction and Construction Joint Quality on the Static Performance of Concrete Arch Dams

The structural integrity of concrete arch dams is critical to ensuring their long-term stability and safety, particularly under seasonal thermal variations. In this study, the effect of contraction and construction joint quality on the static performance of concrete arch dam safety is evaluated. To achieve this, two different approaches are followed: the first approach focuses on global stability through the calculation of the shear strength reduction factor for certain structural joints, while the second approach assesses the local stress–deformation behavior after incorporating physical gaps into the specific joints. The proposed methodology is applied to the numerical model of a typical concrete arch dam. The results of the global safety evaluation reveal that, in the winter and summer scenarios, the joints in the upper half and middle third of the dam height, respectively, have the most significant influence on the dam stability. The local approach demonstrates that while one type of performance index might indicate acceptable performance, another could reveal underlying safety concerns. Both approaches aim to provide a comprehensive understanding of the dam’s structural integrity under varying conditions, supporting informed decision-making for maintenance and safety measures.