Computational Structural Stability Analysis of Gravity Dams Using Franc-2d

Abstract

This paper assesses the structural safety and sliding stability of a concrete gravity dam through a fracture mechanics–based methodology integrated with probabilistic analysis. A 47-meter-high dam model is developed using FRANC-2D, applying Linear Elastic Fracture Mechanics (LEFM) and quarter-point elements to simulate crack initiation and propagation under varying reservoir levels. Mode I and Mode II stress intensity factors (K_I and K_II​) are computed to determine thresholds for unstable crack growth. To incorporate the inherent uncertainties in material properties and external loads, a probabilistic framework is implemented. Key parameters such as cohesion, internal friction angle, and applied loads are modelled as random variables. Monte Carlo simulations are conducted to estimate the probability of dam failure. Results indicate that fracture behavior is highly sensitive to changes in both loading and material characteristics, highlighting the importance of probabilistic tools in dam safety evaluations. This integrated approach enhances the accuracy of long-term performance predictions and supports informed maintenance and risk mitigation strategies.