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Sciences Funding Project of Hunan Province","award":["21B0226"],"award-info":[{"award-number":["21B0226"]}]},{"name":"Natural Sciences Funding Project of Hunan Province","award":["01"],"award-info":[{"award-number":["01"]}]},{"name":"Excellent Youth Fund Project of Hunan Provincial Education Department","award":["U2268213"],"award-info":[{"award-number":["U2268213"]}]},{"name":"Excellent Youth Fund Project of Hunan Provincial Education Department","award":["42172322"],"award-info":[{"award-number":["42172322"]}]},{"name":"Excellent Youth Fund Project of Hunan Provincial Education Department","award":["42007419"],"award-info":[{"award-number":["42007419"]}]},{"name":"Excellent Youth Fund Project of Hunan Provincial Education Department","award":["2018YFC1505403"],"award-info":[{"award-number":["2018YFC1505403"]}]},{"name":"Excellent Youth Fund Project of Hunan Provincial Education Department","award":["2020JJ5981"],"award-info":[{"award-number":["2020JJ5981"]}]},{"name":"Excellent Youth 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Plan","award":["2020JJ5981"],"award-info":[{"award-number":["2020JJ5981"]}]},{"name":"China Railway Group Limited Technology Research and Development Plan","award":["21B0226"],"award-info":[{"award-number":["21B0226"]}]},{"name":"China Railway Group Limited Technology Research and Development Plan","award":["01"],"award-info":[{"award-number":["01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The precise identification of railway subgrade defects remains a significant challenge for the railway industry globally. Due to the limitations of individual monitoring techniques, comprehensive information on subgrade defects cannot be obtained. In fact, the presence of subgrade defects can significantly increase the risk of traffic accidents during high-speed train operations, which may affect the safety of train operations and economic development. The monitoring of subgrade health status is used as a pre-disaster planning method that is urgently required to avoid accidents and guide the maintenance strategy. Therefore, a novel \u201cintegrated\u201d holistic monitoring approach for subgrade structures is presented based on satellite remote sensing, a comprehensive inspection vehicle, and a ground-based testing technique. Additionally, the monitoring content is more clearly defined during the service life of the subgrade. The method is used to investigate the location, development trend, and the cause of subgrade defects on the Shanghai\u2013Nanjing high-speed railway. Some new viewpoints are put forward: First, the monitoring content for assessing the health status of the subgrade should encompass the foundation settlement, the track geometry status, and the monitoring of deformation and defects within the subgrade. Second, the mileage points K235 and K299 of the subgrade, as well as K236 and K237 of the bridge\u2013subgrade transition sections, are estimated to be locations with potential defects based on the differential InSAR and track quality index. Third, the result of settlement monitoring and ground-penetrating radar analysis illustrates that sections K235 +540 to +680 and K299 +680 to +750 are diagnosed as defect positions triggered by the rapid drop of water level and engineering activity, respectively. Fourth, the \u201cintegrated\u201d holistic monitoring technique for subgrade service status might be expected to be a promising method that can be useful in developing maintenance plans and implementing fault recovery for railway infrastructure.<\/jats:p>","DOI":"10.3390\/rs16111972","type":"journal-article","created":{"date-parts":[[2024,5,30]],"date-time":"2024-05-30T10:42:34Z","timestamp":1717065754000},"page":"1972","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["An Integrated Multisource and Multiscale Monitoring Technique for Assessing the Health Status of High-Speed Railway Subgrade"],"prefix":"10.3390","volume":"16","author":[{"given":"Yuanxingzi","family":"He","sequence":"first","affiliation":[{"name":"School of Civil Engineering, Central South University, 68 Shaoshan Road, Changsha 410075, China"},{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Central South University, Changsha 410075, China"}]},{"given":"Yongwei","family":"Li","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Central South University, 68 Shaoshan Road, Changsha 410075, China"},{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Central South University, Changsha 410075, China"}]},{"given":"Linrong","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Central South University, 68 Shaoshan Road, Changsha 410075, China"},{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Central South University, Changsha 410075, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,30]]},"reference":[{"key":"ref_1","unstructured":"National Railway Administration of the People\u2019s Republic of China (NRAPR) (2023, January 04). 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