【摘要】 为揭示拓宽路基荷载下管桩复合地基沉降变形特征及采用管桩处治技术缓解地基差异变形效果,开发土工构造物变形测试系统,升级传感器电测手段,建立与实际应力相符的离心试验模型,并借助有限元数值分析方法,系统研究了新老路基表层和管桩复合地基变形性状。研究结果表明:管桩处理能够快速控制软土地基的沉降,进而有效缓解拓宽新老路基的差异沉降;新老路基的沉降量对路堤高度的变化比较敏感,路堤填方高度变化会带来较大的地基沉降量的变化;路堤填方高度越小,管桩对于减少新老路堤变形的作用就越明显;在拓宽路基荷载的作用下,管桩复合地基最大沉降值位于拓宽荷载的形心垂线处。更多还原

【Abstract】 In order to reveal settlement deformation characteristics of the pipe pile composite foundation and the alleviate difference effect of deformation of pile foundation treatment technology under the embankment load,this paper developed the centrifugal field geotechnical structure deformation test system,upgraded the sensor measuring means,established the real stress correspond to the centrifuge model test,analyzed the pipe pile composite foundation deformation of the new and old subgrade based on the finite element numerical analysis method.The results show that the pipe pile processing can quickly control the settlement of soft soil foundation,so as to effectively alleviate the new and old subgrade differential settlement.The height of the embankment is more sensitive to the change of the height of embankment fill,the change can bring the larger settlement of foundation.The smaller the embankment fill height is,the more obvious the effect is.Under the widening embankment loads,the maxium settlement of pipe pile composite foundation occurs at the centroid vertical section of widening load value.更多还原