Influence of damage on the stability of masonry arches.

This article focuses on the structural stability of historic masonry arches under horizontal loading, particularly examining how localized damage modeled as a reduction in thickness along the intrados affects their collapse behavior. Using a kinematic limit analysis approach grounded in Heyman's theory, the study conducts a parametric analysis across varying arch geometries and damage positions to identify critical locations that most reduce load-bearing capacity. Results indicate that arch thickness significantly influences structural performance, especially in flatter arches with low rise-to-span ratios, while damage near the springings and within the second kinematic block consistently leads to the greatest vulnerability. The proposed method offers a computationally efficient tool for heritage professionals to assess damage sensitivity and prioritize conservation efforts without the complexity of advanced numerical models.