全风化花岗岩路基改扩建差异沉降处治分析

Analysis on Differential Settlement Treatment of Reconstruction and Extension of Fully Weathered Granite Subgrade

为研究不良地质下的路基改扩建工程差异沉降处治问题,以莲株高速改扩建工程为背景,考虑路基内部湿度场变化,并利用有限元软件ABAQUS分别建立不同处治方法下的全风化花岗岩区软土地段的拓宽路基有限元模型,结合位移云图及沉降变形曲线,分析在不同路基拼接技术处治下新老路基、新老地基、路面表面的沉降与侧向变形状况,探讨路基拓宽差异沉降分布。研究表明:拓宽路基沉降集中在施工期及工后1 a内;开挖台阶、铺设土工格栅以及对软土地基进行打桩加固处理能有效减小改扩建路基沉降且控制侧向变形和差异沉降。

In order to study the differential settlement treatment of subgrade reconstruction and expansion project under bad geology,taking the high-speed reconstruction and expansion project of Lianzhu as the background,considering the change of humidity field inside the subgrade,and using the finite element software ABAQUS to establish the softening of the fully weathered granite area under different treatment methods.The finite element model of the widened roadbed of the land section,combined with the displacement cloud map and the settlement deformation curve,analyzes the settlement and lateral deformation of the new and old roadbed,the new and old foundation and the pavement surface under different roadbed splicing techniques,and explores the differential settlement of the roadbed of the reconstruction and expansion project.law.The research shows that the settlement of the roadbed is concentrated in the construction period and within 1a after the construction;the excavation steps,the laying of the geogrid and the piling reinforcement treatment of the soft soil foundation can effectively reduce the settlement of the subgrade and control the lateral deformation and differential settlement.