重复荷载作用下高液限粘土路基永久变形特性分析

重复荷载作用下高液限粘土路基的永久变形对道路正常运行有较大影响。结合FALC3D软件,建立高液限粘土（路堤）及其水泥改良土（路床）的路基弹塑性本构模型,分析路基在不连续半正弦波荷载下产生的动力响应。分析结果表明：在重复荷载作用下土体的永久变形逐渐累积,随着加载次数增加,初始屈服面不断增大,最后趋近于最大加载面;在重复荷载作用下,土体变形在荷载作用初期变形较大,随着荷载重复次数的增加,变形速率逐渐减小;水泥改良后的高液限粘土路床具有抵抗变形能力。该研究对于高液限粘土地区的高速公路建设具有重要的理论意义和实际价值。

Permanent Deformation Characteristics of High Liquid Iimit Clay Subgrade Under Repeated Loads

The permanent deformation of the High liquid limit clay subgrade under repeated loading has a great influence on normal operation of road.The elastic-plastic constitutive model of subgrade was established by FLAC3D,which was consisted of high liquid limit clay（embankment part） and cement soil treatment（roadbed part）,to analyze the dynamic response of subgrade under the discontinuous semi-sinusoidal dynamic load.The Studies have shown that： Soil＇s permanent deformation will gradually be accumulated for the repeated load,the initial yielding surface increased to the maximum load surface.Under the repeated loading,the permanent deformation is obvious during the early cycles of loading.With the loading number increasing,the growing rate of soil deformation decreases.The dynamic strength of high liquid limit clay cement stabilization has a prominent increase.The studies have important theoretical and practical meanings for highway engineering.