Integrated GBInSAR and thermo-mechanical modeling for rock slope displacement analysis across geometrical complexities

Repeated thermal cycles influence rock slope evolution inducing stresses that can initiate and propagate fractures. Ground-Based Interferometric Synthetic Aperture Radar (GBInSAR) monitors the mechanical behavior and superficial displacement, including thermally-induced, useful for precursor displacements detection before landslide onset and collapse. A coupled thermo-mechanical Finite Element Method (FEM) is used to investigate thermal effects on rock slope stability to (i) understand how slope geometry influences heat flux and stress; (ii) assess thermo-mechanical parameter impact on the thermo-mechanical response; and (iii) simulate slope geometry and aspect effects on system response through different boundary temperature. Finally, simulated FEM superficial displacement maps are compared with GBInSAR measurements from two Italian Alps real sites. Results demonstrate that curvature and changes in slope inclination significantly concentrate temperature increments and associated stresses. Specific heat affects both temperature distribution and displacements, while Young's modulus and thermal expansion coefficients influence displacement and stress magnitudes. External temperatures controlled by slope aspect impact movement modes, producing torsional effects, especially for slender features. The numerical predictions and GBInSAR data comparison reveal a strong agreement in displacement distribution, validating the model's ability to capture observed deformation patterns. These findings highlight the role of thermal forcing in rock slope deformation and its sensitivity to geometric features and material properties. The results offer valuable insights for monitoring planning, by identifying thermally sensitive areas, for interpreting field data, isolating thermal contributions from total displacements; and for slope stability analysis, by providing a framework to assess thermo-mechanically induced stress and deformation under current and future climatic conditions.