Residual service life prediction for bridges undergoing slow landslide-induced movements combining satellite radar interferometry and numerical collapse simulation.

• Novel prognostic method for bridge SHM based on InSAR analysis. • Applied Element Method to simulate the behaviour of bridges up to total collapse. • Combination of InSAR monitoring and numerical modelling. • Estimation of residual service life of bridges affected by slow deformation phenomena. • Application to the Albiano-Magra Bridge case study collapsed in 2020. This paper proposes an innovative approach for structural prognosis of bridges, that combines displacement information obtained by Synthetic Aperture Radar Interferometry (InSAR), applied to satellite data, with structural and collapse analysis performed through numerical modelling. The purpose of this multidisciplinary approach is to recognize potentially critical conditions and predict the time to failure of bridges affected by slow deformation phenomena, such as slow landslide-induced movements. The methodology involves advanced pre- and post-processing techniques for satellite SAR acquisitions, which allow tracking two-dimensional displacement evolution of multi-span bridges with properly defined error bounds, and uses numerical modelling to simulate damage propagation and structural behaviour up to total collapse. The effectiveness of the proposed synergy between remote displacement measurements and numerical collapse analysis is exemplified through the application to the Albiano-Magra Bridge in Italy, which collapsed on April 8th, 2020. The results have allowed to identify the triggering cause of the collapse and have provided an estimate of the residual service life of the bridge, with increasing reliability as the available satellite monitoring period gets longer. The work demonstrates that a combined analysis considering both satellite measurements and numerical modelling can improve the comprehension of the phenomena concerning the structural collapse due to slow deformations and its prevention. [ABSTRACT FROM AUTHOR]