Assessing subsidence-induced damage on heritage: an integrated remote sensing and structural modelling approach

Cultural heritage sites all over the world are increasingly threatened by regional-scale subsidence. Addressing this issue necessitates a deep understanding of how ground settlements impact structural integrity. Traditional approaches, primarily reliant on in-situ investigations, are not only costly but also constrained by their installation in anticipated vulnerable structures. Recent advances in satellite technologies, historically used in geophysical studies of natural phenomena like glaciers and earthquakes, have shown potential in detecting structural deformations. In particular, Interferometric Synthetic Aperture Radar (InSAR) techniques have the capability to measure ground subsidence and building displacements with millimetric precision, they are independent from weather and light conditions, and can provide frequent, weekly updates over extensive areas. Furthermore, the availability of historical data enables retrospective monitoring, eliminating the requirement for pre-installed in-situ monitoring systems. Nevertheless, the interpretation of InSAR data in isolation falls short without correlating it to structural damage. This study aimed to bridge the existing gap by integrating InSAR monitoring with Finite Element Method (FEM) modelling, specifically applied to a historic church in Poland affected by mining-induced ground settlements. The objective was to predict the structural damage over time caused by subsidence at this heritage site. InSAR data for a reference region, including the area around the church, was acquired and processed using Multi-Temporal InSAR techniques. This was complemented by regional-scale interpolation to address data gaps near the church. These displacement measurements were then incorporated into a computational model of the church, to estimate the level of structural damage. The FEM model, informed by InSAR-derived displacements, was used to assess the impact of various factors on the church's structural response. These factors included settlement profiles and soil-structure interaction characteristics. Through the proposed integration, we aimed to gain critical insights into the resilience of cultural heritage sites and develop novel, practical tools for analysing structures at risk.