<![CDATA[The structural stability and serviceability of transport infrastructure in mountainous regions are increasingly compromised by climate- and human-induced geohazards. Traditional ground-based geodetic monitoring methods, while reliable, are often limited by high costs, labor demands, and restricted spatial coverage. This study aims to develop a cost-effective monitoring framework integrating satellite remote sensing and numerical stability analysis to detect precursory slope movements in mountainous terrains. The study utilized 43 Sentinel-1 (S1) C-band SAR images acquired between January 10, 2022, and May 29, 2023. Using the Persistent Scatterer Interferometric SAR (PSInSAR) method, the research monitored a critical section of Kennon Road in Benguet, Philippines. The S1-PSInSAR analysis identified precursory instability beginning in March 2023, approximately two months before a major slope failure occurred on May 31, 2023, due to heavy rainfall from a super typhoon. The results indicate a maximum cumulative displacement of 34 mm along the radar line-of-sight. These findings were cross-validated using limit equilibrium analysis in Slide2 software, which yielded safety factors (FS) significantly below unity for all methods, confirming the inherent instability of the slope even under dry conditions. The study concludes that despite technical challenges such as dense vegetation and atmospheric interference in mountainous terrain, the integrated PSInSAR and numerical modeling approach provides a viable, near-real-time tool for enhancing the resilience of transport infrastructure networks in the Philippines.]]>
