Seismic Reliability Analysis of Concrete Arch Dams Incorporating Different Valley Shapes: Using a Surrogate Model
Year: 2026
Type: article
Abstract: Concrete arch dams are widely constructed in regions featuring deep valleys and distinctive valley shapes because of their high efficiency and economical use of materials. However, the stability of these structures under earthquake loading requires accurate and comprehensive analyses. Accordingly, this study investigates the seismic reliability of these dams, focusing on the effect of different valley shapes on dam safety in terms of the reliability index (β). The research variables—including the slopes on the left and right sides of the valley, the position of the valley bottom and peak ground acceleration of earthquake have been utilized across various scenarios. In this study, a response-surface surrogate model (RSM) was used to generate explicit functions describing dam behavior, ABAQUS was used for finite element (FE) analysis of the models, and MATLAB coding was employed to implement the methods for estimating the probability of failure and the β index. In addition, the probabilistic seismic response of the dams under different valley-shape conditions was evaluated through implicit dynamic analysis using the Northridge, Friuli, and Trinidad earthquake records at different intensity levels. Examining four valley shapes (i.e., V-shaped, symmetric and asymmetric polygonal, and U-shaped) revealed that valley shape strongly affects stress distribution and seismic load-carrying capacity. Valley shape should therefore be considered a key factor in the design and seismic performance assessment of arch dams. The results also demonstrated that symmetric valleys provide the most suitable sites for arch-dam construction and identified valley-shape asymmetry as the most important factor increasing the probability of failure. Overall, this research represents an important step toward developing simulation-based and probabilistic approaches to the design of earthquake-resistant dams.
Institution: Islamic Azad University, Tehran
Language: English
Topic: Dam Engineering and Safety
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7225348421