## 4 Conclusions  
This study, conducted within the context of the geotextile bag revetment project along Xinjiang's Tarim River, systematically investigates both the microstructural characteristics and macroscopic performance of geotextile bags in practical engineering applications. By implementing a slurry coating protection method and subjecting optimized samples to accelerated aging tests, the protective efficacy was thoroughly validated. The principal findings are as follows:  
(1) Microscopic examination using electron microscopy coupled with mechanical strength testing revealed that sediment deposition significantly enhances both fiber integrity and the mechanical properties of geotextile bags employed in the Tarim River water conveyance embankment. Building upon this discovery, a manual slurry coating protection method was developed. Subsequent adhesion tests demonstrated that a clay-based slurry exhibits superior bonding performance with geotextile bags compared to alternative compositions.  
(2) When targeting the two primary aging factors, UV radiation and temperature, the experimental results confirmed that the slurry coating serves as an effective light barrier while substantially reducing heat transfer under simulated high-temperature conditions, exhibiting remarkable thermal insulation properties.  
(3) Comprehensive analysis employing range analysis, variance analysis, and projection pursuit regression (PPR) for thermal insulation performance evaluation established the following parameter significance hierarchy: slurry thickness > geotextile thickness > clay content. The PPR-derived predictive model (Equation (5)) enables the accurate estimation of thermal insulation performance under untested parameter combinations.  
(4) The performance validation of optimally slurry-coated samples through accelerated aging tests and electron microscopy observations yielded significant results: the coating treatment markedly improved geotextile strength retention rates, effectively mitigating performance degradation in both UV-exposed and high-temperature environments. Microscopic analysis conclusively verified the slurry layer's protective effect on fiber microstructure preservation.  
T.C.: software, validation, formal analysis, investigation, writing--original draft preparation; X.L.: conceptualization, methodology, writing--review and editing, supervision, funding acquisition; Y.Q.: conceptualization, writing--review and editing, supervision; H.W.: validation, investigation, writing--review and editing; supervision. All authors have read and agreed to the published version of the manuscript.  
Xinjiang Uygur Autonomous Region Natural Science Foundation General Project: \"Research on the Stability Characteristics and Protection Mechanism of Bottom Soil Bags for Fen Xi Sha River Embankment Engineering\" (2022D01A183); Financial support provided by the research project \"Xinjiang Key Laboratory of Water Conservancy Engineering Safety and Control\" for graduate students in 2022 (ZDSYS-YS-2022-05).  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
We sincerely thank the Xinjiang Uygur Autonomous Region Natural Science Foundation General Project: \"Research on the Stability Characteristics and Protection Mechanism of Bottom Soil Bags for Fen Xi Sha River Embankment Engineering\" (2022D01A183); Financial support provided by the research project \"Xinjiang Key Laboratory of Water Conservancy Engineering Safety and Water Disaster Prevention and Control\" for graduate students in 2022 (ZDSYS-YS-2022-05).  
Conflicts of Interest: The authors have no relevant financial or non-financial interests to disclose.