高海拔山区加筋陡坡路堤长期监测与稳定性分析研究

Long-Term Monitoring and Stability Analysis of Geogrid-Reinforced Steep Slopes in High-Altitude Mountainous Areas

摘要: 为评估新疆高海拔山区土工格栅加筋陡坡路堤在季节性冻融与强蒸发环境下的长期服役性能，本研究依托G0711高速公路工程加筋陡坡路段，通过布设柔性位移计、土压力盒及温湿传感器，对典型断面开展为期一年的原位监测(2023年8月~2024年7月)。监测内容涵盖温度场时空演化、湿度分布规律、土压力重分布及土工格栅应变响应。结果表明：温度场呈现水平方向显著梯度及垂向衰减特征，随着向加筋土陡坡内部沿深，温度滞后性逐渐明显；湿度场受蒸发作用主导，坡表干燥化剧烈，长期无雨导致水分单向迁移，内部湿度缓冲能力有限；土压力在近坡面区域因沉降变形与土拱效应显著低于内部，非冻胀区土压力冬季降低而雨季因密实度增加上升；格栅应变呈现“冬增夏减”循环特性，近坡面应变高于内部。监测高海拔山区加筋土陡坡可为在寒区道路边坡设计提供理论和应用参考。

Abstract: To evaluate the long-term service performance of geogrid-reinforced steep embankment slopes in high-altitude mountainous areas of Xinjiang under seasonal freeze-thaw cycles and intense evaporation conditions, this study, based on a steep reinforced slope section of the G0711 Expressway project, conducted one year of in-situ monitoring (August 2023 - July 2024) on a typical cross-section. Flexible displacement gauges, earth pressure cells, and temperature-humidity sensors were deployed. Monitoring encompassed the spatiotemporal evolution of the temperature field, humidity distribution patterns, earth pressure redistribution, and geogrid strain response. The results indicate: (1) The temperature field exhibits significant horizontal gradients and vertical attenuation characteristics; temperature hysteresis becomes increasingly pronounced with depth into the reinforced slope. (2) The humidity field is dominated by evaporation, with severe desiccation occurring on the slope surface. Prolonged drought conditions lead to unidirectional moisture migration, while the internal moisture buffering capacity is limited. (3) Earth pressure near the slope face is significantly lower than that in the interior due to settlement deformation and soil arching effects. In non-frost heave zones, earth pressure decreases in winter but increases during the rainy season due to enhanced compaction. (4) Geogrid strain exhibits a cyclic pattern of “winter increase and summer decrease,” with strain near the slope face being higher than in the interior. The monitoring of reinforced steep slopes in high-altitude mountainous areas provides theoretical and practical references for the design of road embankments in cold regions.