高速铁路路堤传递地基差异沉降特性及控制限值研究

为研究高速铁路地基差异沉降在路堤中的传递扩散特性,运用有限元方法,分析了路基在小变形条件下地基差异沉降与路基面不均匀变形的映射关系,并在得到土工离心模型试验校正的基础上,讨论了地基差异沉降模式、路堤高度等因素对路基面不均匀变形的影响规律.研究表明:地基差异沉降在路堤中的扩散程度随地基差异沉降渐变段长度与路堤高度比值的增大而减小,比值大于3~5以后,地基差异沉降与路基面不均匀变形具有良好的一致性;路基面不均匀变形与地基差异沉降呈正相关性,并随路堤高度、地基差异沉降渐变段长度的增加而减小;基于路基面不均匀变形限值提出了地基差异沉降控制标准,丰富了高速铁路路基沉降变形控制技术指标体系.

Analysis on conduction characteristics from embankment and control limits of foundation differential settlement for high speed railway

In order to find the differential settlement transfer and diffusion characteristics for high speed railway, with the help of finite element method, the mapping relationship of the differential settlement and inhomogeneous deformation of the subgrade surface is analyzed. On the basis of geotechnical centrifuge model test correction, discuss how the factors such as foundation differential settlement mode and embankment height affect the inhomogeneous deformation of the subgrade surface. The research show that, the proliferation degree of differential settlement decrease with the ratio of the gradient length of foundation differential settlement to the embankment height increase. When the ratio is greater than 3 to 5, the foundation differential settlement and the inhomogeneous deformation of subgrade surface have a good consistency. The inhomogeneous deformation of subgrade decreases with the embankment height and the gradient length of foundation differential settlement increase. Based on the uneven subgrade surface deformation limits, the foundation differential settlement control standard is put forward. It enriches the high speed railway embankment settlement deformation control technology index system.