Temperature changes may cause irregular soil uplift or thawing settlements in frozen soil areas, potentially affecting the safe operation of High-Speed Railways (HSR). Analyzing and predicting these deformation characteristics is thus critical. However, the conventional forecasting and analysis techniques rarely considered factors such as dynamic parameter variations, uncertainties, and measurement errors, which hinder accurate regional scale forecasting. To bridge this gap, this paper introduces a novel time-series coupling method, which integrates post-processing deformation from Interferometric Synthetic Aperture Radar (InSAR) with a frost heave model (FHM), facilitated by the ensemble Kalman filter (EnKF) assimilation algorithm. We obtained deformation observations along the HSR using Persistent Scatterer InSAR (PS-InSAR) technology in combination with time series post-processing techniques. Considering the causative factors for deformation, we structured the FHM. By integrating FHM with observational data using the EnKF algorithm achieved an efficient upgrade of the posterior distribution of model parameters. This integration significantly improves the predictive accuracy, it facilitates an efficient update to the posterior distribution of model parameters, leading to enhanced prediction accuracy of our model. Our experimental results indicate that the effectiveness of this approach, with observational data assimilation into FHM reducing the average Root Mean Square Error (RMSE) to a mere 0.247 mm. Concurrently, both the Normalized Reduction Error Index (NER) and the Assimilation Efficiency Factor (EFF) values surpassed 0.60 and 0.84 respectively. These underlines signify a successful update of our model parameters, which in turn elevates the accuracy of future deformation predictions, thereby promising safer railway operations.
多年冻土是青藏高原主要的,也是关键的土壤类型。其发生、发展对青藏高原生态、水文等都有重要的影响。自出现合成孔径雷达干涉技术(Interferometric Synthetic Aperture Radar,In SAR)以来,对多年冻土区土壤冻融的研究就出现了一种新的手段,利用该方法可以有效探测近地表土壤的冻融状态。本文首先介绍了多年来各国的星载合成孔径雷达(SAR),然后阐述了该方法的理论基础,最后对差分干涉合成孔径雷达技术(D-In SAR)、小基线子集方法(Small Baseline Subset Approach,SBAS-DIn SAR)和永久散射体技术(Permanent Scatterers,PS)都做出了描述。综上所述,利用适合的SAR数据和有效的In SAR方法研究青藏高原冻土区的冻融状况,可以为今后的科学研究提供范围广、类型多样、精度高的基础数据。