改扩建软土路基的变形分析与控制对策

Deformation analysis and control technique of the roadbed reconstruction and extension for soft soil

摘要: 针对典型公路的改扩建工程,通过现场原位试验对比研究了新老路基地基土体的差异性,老路基土体力学性质整体好于新路基,但这种差异主要表现在浅部一定深度范围内,且随老路堤高度增加而增大,超过这一深度范围后,新老路基土体力学性质差异不大。借助数值预测方法,分析了拓宽路基在运营期的沉降变形和可能引起的路面病害。结果表明:未经处理的软土地基会引起路基较大的工后变形,同时带动老路基产生固结沉降,影响新修路基的稳定性;而新老路基土刚度差异较大时,易导致新老路基产生过大的差异沉降。防治工程病害的关键在于提高路基的整体强度和稳定性以及新老路基的变形协调控制。

Abstract: For a typical project of roadbed reconstruction and extension,performances of the soil in widening and existing road foundation were compared by some in-situ tests.It is found that mechanical properties of the soil in original road foundation as a whole are better than those in the widening road foundation.However,the differences are mainly at a certain depth,and enlarge with increase in the existing roadbed height.Beyond the range of the depth,the feature disappears.Analysis of widening roadbed