Deformation Monitoring and Analysis of Mountainous Cutand Fill Airport Construction Considering Topographic andGeomorphological Features: A Case Study of Weining Caohai Airport

Abstract

The rapid expansion of aviation infrastructure has intensified requirements for mountainous airport construction, where engineering activities involving extensive fill embankments and deep excavations induce significant surface deformation that jeopardizes operational safety. Conventional geodetic techniques (e.g., GPS networks and leveling surveys) present limitations in spatiotemporal resolution for large-area, high-precision deformation monitoring requirements. This study investigates surface displacement at Guizhou Weining Caohai Airport through an enhanced time-series InSAR methodology incorporating topographic and geomorphological characteristics. We employ multi-source remote sensing data including ascending/descending orbit SAR acquisitions from China’s Land Exploration Satellite-1 (LT-1) mission (2023-2025) and Sentinel-2 optical imagery. Our methodological innovations include: 1) Optimized homogeneous pixel identification criteria through integration of a priori topographic parameters (slope gradient, aspect orientation) and land
cover classification; 2) Enhanced phase reliability through weighted confidence interval estimation coupled with maximum likelihood phase optimization, significantly improving measurement accuracy in complex terrain; 3) Development of a slope-aspect-constrained 2D deformation decomposition model leveraging multi-orbit SAR geometries to resolve vertical and characteristic horizontal displacement components. The experimental results validate the technical efficacy of the improved InSAR framework for mountainous airport monitoring, establishing a scientific foundation for infrastructure safety management and geohazard mitigation strategies.