Validating Railway Infrastructure Deformation Monitoring: A Comparative Analysis of Field Data and TerraSAR-X PS-InSAR Results

Abstract

Railway infrastructure maintenance faces a challenge posed by the laborious task of monitoring widespread deformation, which is critical for ensuring safety. This study utilized the Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) technique with high-resolution TerraSAR-X satellite images to measure and analyze deformation at the operating track. Tailored through parameter optimization to fit regional topography and validated against field measurements, PS-InSAR was applied across a 30km by 50km area over two years. The analysis demonstrated that PS-InSAR could efficiently generate high-accuracy time-series data, capable of detecting both the uplift and subsidence processes. It highlighted the importance of augmenting single-point subsidence values with comprehensive time-series analysis for a complete deformation assessment. The study concluded that PS-InSAR is an accurate and cost-effective tool for large-scale linear infrastructure monitoring, despite technological constraints such as radar imaging frequency and the lack of high-resolution sources. Considering these constraints, future research will prioritize developing an enhanced algorithm capable of analyzing both urban and suburban areas, accommodating varying numbers of point scatterers. © Korean Society of Civil Engineers 2024.