基于BBM模型的非饱和路堤变形机理与控制参数研究OA

Taking the new embankment project of Hangzhou Xixian Dyke as the research object,the deformation characteristics of unsaturated soil embankment during construction and operation periods were investigated.Firstly,a numerical model was established based on the Barcelona Basic Model(BBM)and the actual engineering section.Secondly,engineering conditions including initial compaction load,initial water content,and vehicle load during operation were set according to engineering practice,and multiple working condition combinations were constructed.Thirdly,according to the stress-yield curve relationship theory,the mechanical response of embankment soil layers under different working conditions was analyzed.Finally,the unfavorable working condition of"saturated embankment with vehicle load"was set.The stress-yield curve relationship and deformation characteristics of embankment soil layers under various working conditions were specifically analyzed.The control effects of each engineering condition on embankment deformation were clarified.The results show that initial compaction load has a significant effect on restraining the subsequent plastic deformation of the embankment.Increasing the initial compaction level can effectively reduce embankment deformation during the operation period.Compared with the optimum water content state,low initial water content weakens the initial compaction effect of the soil,resulting in a reduced ability to control embankment deformation during the operation.The wetting process significantly decreases the mechanical strength of the soil,making the critical vehicle load inducing embankment plastic deformation considerably lower than the initial compaction load.The bearing capacity of the embankment significantly decreases under wetting conditions.