【摘要】 针对兰州西至中川机场城际铁路沿线分布着大量饱和黄土，由于天然承载力低，无法满足工程建设要求这一问题。依据复合地基理论，提出用水泥土搅拌桩加固饱和黄土地基。通过FLAC3D软件建立，进行承载特性分析。根据数值模拟结果，分析各级荷载作用下桩顶沉降量，绘制荷载—沉降曲线，确定单桩竖向极限承载力为210kN及承载力特征值为105kN，并与现场试验段实测值进行对比，曲线较为接近，即数值模拟能够较好的反映现场真实情况。同时，分析了桩身轴应力、桩侧摩阻力在桩顶各级荷载作用下沿深度的变化情况；最后，分析了桩端阻力和桩侧摩阻力对上部荷载的分担比例。数值模拟的结论，为类似工程的设计研究有一定借鉴作用。更多还原

【Abstract】 A large amount of saturated loess is distributed along the Lanzhou West to Zhongchuan Airport Intercity railway, in which the natural carrying capacity is low and cannot meet the requirements of engineering construction.Based on the theory of composite foundation, the soil-cement pile is proposed for strengthening the saturated loess foundation. FLAC3D software is employed to analyze the bearing characteristics. According to the numerical simulation results, pile top settlement under different levels of loads is analyzed, in which, we obtain the load-settlement curve; the vertical ultimate bearing capacity of single pile is determined to be 210kN and the characteristic value of bearing capacity is 105kN. Compared with the measured value in the field test section, the results from numerical simulation could better reflect the real situation on site. At the same time, the changes of pile axial stress and pile lateral friction along the depth under the load of pile top are analyzed. Finally, the proportion of pile tip resistance and pile side friction to the upper load is analyzed. The conclusion of numerical simulation may provide the reference in the design and research of similar engineering projects.更多还原