Accurate modelling of the non-linear response of historical masonry bridges under traffic and environmental actions is a complex task, mainly due to masonry anisotropy and its interaction with backfill material. Furthermore, the difficulty in obtaining realistic material parameters for the different bridge components and vital information on internal features may render such undertaking even more challenging. This paper presents a detailed investigation of a five-span masonry railway viaduct located in northern Portugal. Multiple non-destructive tests (NDTs), including sonic, ultrasonic, and GPR tests, have been performed to obtain critical geometrical and mechanical parameters of the masonry parts and backfill of the viaduct. Moreover, environmental vibration tests have been carried out to evaluate the fundamental frequencies and vibration modes of the analysed structure. Subsequently, the test results have been employed to achieve a consistent and objective calibration of the main parameters of a detailed 3D finite element model of the viaduct, which adopts a refined anisotropic macroscale masonry material description. The developed 3D model has been employed to perform a series of non-linear static and dynamic simulations to predict the bridge response under moderate to strong earthquakes. The proposed methodology can be applied to a wide range of historical masonry bridges for improved assessment and to address the design of potential retrofitting solutions.
Acknowledgments
The authors gratefully acknowledge support from the Marie Skłodowska-Curie Individual fellowship under Grant Agreement 846061 (Project Title: Realistic Assessment of Historical Masonry Bridges under Extreme Environmental Actions, “RAMBEA”, https://cordis.europa.eu/project/id/846061. The support from “Infraestruturas de Portugal” is kindly acknowledged. This work was partly funded by FCT/MCTES under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), reference UIDB/04029/2020.
