Modelling and analysis of time-dependent behaviour of historical masonry under high stress levels

Masonry which is subjected to high, sustained stress levels can suffer from long-term damage accumulations. This type of stress-induced damage interacts with other long-term phenomena, such as deterioration and fatigue. In this work, the time-dependent damage which is caused by elevated stress levels is analysed and modelled. A one-dimensional rheological model, which was calibrated on the results of an extensive experimental test campaign, is extended to a three-dimensional version. The time-dependent constitutive relations are implemented in a finite element code. The issues of triaxial stresses and mesh-dependency are addressed. In a first application, the model is used to simulate the long-term behaviour of a masonry tower. Secondly, the effects of time-dependent stress redistributions on the long-term stability of three-leaf masonry are investigated.