Over-wet Loess Subgrade Deformation Characteristics And Disposal Technology Research

In recent years,the speed of the western loess region road network construction was improved after implementing the western development strategy in China.More technologies were required in the construction of collapsible loess roadbed for a large area of the loess area highway construction.As for the construction of highway loess roadbed,the loess roadbed distress gradually appeared,especially over-wet loess subgrades caused.Therefore,it has a certain guiding significance to analyze physical and mechanical properties of over-wet loess in the existing experimental conditions,construct reasonable over-wet loess constitutive model,then use it to simulate over-wet loess subgrade degeneration characteristics.In this research,loess collapsibility laterals confined compression test and double curve test for over-wet were done to analyze the influence of moisture content and compaction on loess deformation characteristics.Then elastoplastic constitutive model,which considered degree of compaction and moisture content change,was putted forward based the influence and Drucker Prager model provided by ABAQUS.After these,the finite element simulation was done to calculate the deformation,displacement and other parameters in over over-wet loess subgrade.The deformation and displacement characters were analyzed based on the results of finite element simulation.The results of loess collapsibility laterals confined compression test showed that loess compression feature was improved with decreasing of compaction.And the results of double curve test showed that collapsibility were decreased with the increasing of moisture content.The results of finite element simulation showed that the vertical deformation and displacement were increased with the improvement of compaction or decreasing of moisture content.Stresses of loess subgrade were decreased by drainage facilities.Inhomogeneous deformations were decreased by the reinforce for highway foundation.Sand cushion showed little influence on inhomogeneous deformations in subgrades.