The Analysis of Non‐stress Effects on Historical Stone Bridge Structures (Monitoring, Theoretical Analysis, Maintenance)

Due to non‐stress cyclic effects of temperature and moisture, stone bridge structures are subjected to deformations, a gradual growth of permanent deformations, crack development and subsequent disintegration of the stone masonry of bridge vaults. A theoretical analysis of the stress‐state and deformations of the stone bridge structure caused by non‐stress effects and the in‐situ monitoring of deformation changes of the breast walls and the bridge vaults of the historic structure of Charles Bridge (from the mid‐14th century) manifested a response and a growth in permanent deformations and disintegration of the stone bridge structure due to the effects of temperature and moisture. The behaviour of the bridge structure is significantly affected by the interaction of the vault bridge structure with the bridge body filler when exposed to the above‐mentioned non‐stress effects. Special attention must be paid to the spacing effect of filling layers on the stone bridge structure. When repairing historical stone bridge structures, the rehabilitation methods commonly used increase the total rigidity of the stone bridge structure and thus its sensitivity to non‐stress effects caused by changes in temperature.