侧向地应力对深挖方红层软岩路基上拱的影响研究  

Study on the influence of initial lateral in-situ stress on heave in the deep excavated red bed soft rock subgrade

作　　者：张锐[1,2] 罗辉[1,3] 余雷 秦灵伟 张喜伟 吴高桥 ZHANG Rui;LUO Hui;YU Lei;QIN Lingwei;ZHANG Xiwei;WU Gaoqiao(School of Traffic and Transportation Engineering,Changsha University of Science and Technology,Changsha,Hunan 410114,China;State Key Laboratory of Green and Long Life Road Engineering in Extreme Environments,Changsha University of Science and Technology,Changsha,Hunan 410114,China;Hunan Zhonghe Geotechnical Engineering Co.,Ltd.,Changsha,Hunan 410003,China;China Railway Economic and Planning Research Institute,Beijing 100038,China)

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410114 [2]长沙理工大学极端环境绿色长寿道路工程全国重点试验室,湖南长沙410114 [3]湖南中核岩土工程有限责任公司,湖南长沙410003 [4]中国铁路经济规划研究院有限公司,北京100038

出　　处：《岩石力学与工程学报》2024年第10期2396-2404,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52278432);中国国家铁路集团有限公司科技研究开发计划项目(K2019G045)。

摘　　要：为揭示侧向地应力对红层软岩路基上拱变形的影响,提出相应的计算分析方法及参数获取方法。采用自研的可调控侧向应力的二维变形试验装置,开展不同侧向应力条件下的卸荷回弹试验和浸水湿化膨胀试验,研究侧向应力、加卸荷和湿化膨胀对红层软岩变形的影响,通过数值模拟探究深挖方红层软岩路基在侧向地应力影响下的上拱变形机制。研究结果表明:侧向地应力导致的上拱变形量占总变形量的65.8%~67.8%;相较于无侧向应力,有侧向应力条件下上拱变形量增加1.6~1.9倍;湿化膨胀产生的上拱变形量是侧向应力引起上拱变形量的0.5倍。上述因素对上拱变形量的影响大小依次为:开挖卸荷、侧向应力、湿化膨胀。而当侧压力系数增加到0.6以后,对上拱变形影响更为显著。研究表明侧向地应力是红层软岩路基上拱的重要原因之一,研究结果可为红层软岩路基上拱治理提供理论支撑或参考。A two-dimensional swelling system was developed in this study to investigate the effect of the lateral stress on the heave behavior of a natural red mudstone embankment under deep excavation.The heaving under a combination of stress path of vertical loading-unloading with the application of the lateral stress was examined in detail.Then,a comprehensive numerical simulation was conducted to characterize the heave of the deep-excavated embankment.Results indicates that the lateral stress is the main consequence of heaving,which accounts for 65.8%to 67.8% of the total heaving.The application of the lateral stress would result in around 1.6 to 1.9 times of the heave to the laterally unconfined case.On the other hand,the hydration-induced heaving becomes around 0.5 times to that caused by the lateral stress.Therefore,the factors affecting the heave emerge in the sequence of the lateral unloading,the magnitude of the lateral stress and the swelling induced by water immersion.The evident heaving of the embankment is seen when the lateral stress ratio is larger than 0.6.In addition,The results show that lateral in-situ stress is one of the important reasons for the heave of the red bed soft rock subgrade.The research results can provide theoretical support or reference for the treatment of the heave.

关 键 词：路基基础 高速铁路 红层软岩路基 侧向地应力 上拱变形 数值模拟 

分 类 号：TU47[建筑科学—结构工程]