Risk Assessment of Cultural Heritage Buildings using InSAR Monitoring

Cultural heritage assets represent core aspects of history, tradition, culture, emotions and values of a society. Due to their unique nature, they require preservation approaches that respect their identity while addressing challenges such as the occurrence of natural disasters, urbanization, and socio-economic changes. In particular, ground deformations can compromise the structural integrity of cultural heritage buildings. This study proposes a framework to integrate the ground displacement values derived from Interferometric Synthetic Aperture Radar (InSAR) into a finite element model of a cultural heritage building, enabling a quantitative link between ground motion and structural response which has been largely overlooked in previous studies. The approach is demonstrated through application to the Riga Central Market (RCM) in Latvia. InSAR analyses were performed for the period 2016 to 2025 using a combination of Small Baseline Subset (SBAS) and Persistent Scatterer Interferometry (PSI) techniques to capture both stable and distributed reflectors. The resulting displacement data were incorporated into a finite element model of the RCM building as prescribed deformations. The results indicate significant ground movement in the RCM building, particularly subsidence in the north-eastern periphery and uplift in the south-eastern corners, consistent with the recorded history of ground movement in Riga related to construction processes and tectonic movements. The proposed framework demonstrates the potential of integrating InSARderived ground displacement data with finite element analysis to support early warnings of settlement-induced cracks in heritage buildings. This approach could be further developed to form the basis of a digital twin for continuous monitoring and predictive maintenance of the RCM.

Keywords: InSAR, Finite Element Model, Ground Displacement, Structural Analysis, Risk Assessment, Small Baseline Subset, Persistent Scatterer Interferometry, Crack Widths, Damage States.