高铁路堤中改性膨胀土工程应用特性试验研究  

Experimental study on application characteristics of improved expansive soil in high-speed railway embankment

作　　者：李朝辉[1] 张柯宏 程谦恭[3,4] 王文瑞[4] 王艳涛[4] 吕波[4] 王晓瑞[4] 

机构地区：[1]中铁二院工程集团有限责任公司,四川成都610031 [2]中铁第一勘察设计院集团有限公司,陕西西安710000 [3]西南交通大学高速铁路运营安全空间信息技术国家地方联合工程实验室,四川成都610031 [4]西南交通大学土木工程学院,四川成都610031

出　　处：《铁道科学与工程学报》2017年第3期445-454,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(41530639;41372292)

摘　　要：用南宁高铁建设中常遇到的弱性膨胀土及水泥改性膨胀土作路堤填料,填筑1:1高铁路堤模型,依托自行设计的监测系统,对自然降雨蒸发条件下路堤内的含水率、温度、吸力与土压力4种特征参数的变化规律以及沉降变形量进行监测。研究结果表明:膨胀土路堤边坡大气急剧影响深度集中在0.5 m内,最大影响深度可达2~3 m;最大工后沉降量膨胀土路堤面约为5.7 mm,水泥改良土仅约2.5 mm,水泥改良膨胀土可用作高铁路堤建设填料;路堤边坡坡面侧向变形以收缩变形为主,呈现"上部大,下部小"的特点,相同位置处,膨胀土断面变形量大于改良土断面。A high speed railway embankment model equaling to prototype was built by using weak expansive soil and cement-treated expansive soil, which were taken from the high-speed railway construction in Nanning. Under natural rainfall and evaporation conditions, based on the self-designed monitoring system, the changing regularities of moisture content, temperature, suction and soil pressure in the embankment as well as the settlement deformation were monitored. The experiment results indicated： Expansive soil embankment slope atmosphere influence depth sharply concentrated within 0.5 m, the maximum influence depth could reach 2-3 m; the maximum settlement impact depth of the expansive soil embankment surface was about 4.5 mm, while the cement-treated soil was only about 2.5 mm, thus, cement-treated expansive soil can be used as a kind of high-railway embankment filling material. Furthermore, the lateral deformation of embankment slope was mainly shrinkage deformation, showing the characteristics of large on upper part and small in the lower part; and in the same position, the deformation of the expansive soil section was larger than that of the improved soil section.

关 键 词：膨胀土 改性膨胀土 高铁路堤 影响深度 变形量 

分 类 号：TU443[建筑科学—岩土工程]