Study On Settlement Law Of Peaty Soil Foundation Under Embankment

In recent years,with the increasing scale of highway construction in China,it is inevitable to pass through some special foundations,such as peaty soil foundation.Peaty soil has large pores and extremely high water content,resulting in great compressibility and secondary consolidation deformation.Therefore,the embankment settlement after embankment filling on the peat soil foundation,especially after construction,is very large,which has a great impact on the project.Therefore,the settlement characteristics of peat soil need to be further studied.In view of this,this paper relies on the national natural fund project "study on consolidation mechanism and settlement calculation method of peat soil foundation under embankment",and studies on consolidation and settlement characteristics of peaty soil under embankment by means of laboratory test and numerical simulation.1.One-dimensional consolidation test was carried out on undisturbed samples of peat soil in Yunnan province.The variation law of consolidation coefficient,compressibility coefficient,compression index and secondary consolidation coefficient of peat soil was analyzed.2.The numerical analysis model of peat soil foundation under embankment load was established by using PLAXIS,a large general finite element software,to analyze the deformation characteristics of peat soil foundation under embankment load,and the comparison with the monitoring results verified the applicability of the creep model of soft soil.3.The physical and mechanical parameters of peaty soil in different parts of China were summarized,and the failure mode of peaty soil foundation was studied through the numerical calculation of the shear strain and plastic zone expansion in the finite element model,and the difference between the failure mode of peaty soil foundation and silty soil foundation under the action of embankment load was discussed.4.The completion time of main consolidation,the proportion of total settlement and secondary consolidation settlement of peat soil foundation were calculated by finite element method,and the influence of organic matter content on the settlement of peat soil foundation was analyzed.5.Based on the method of multiple linear regression,SPSS software is used to study the influence of soil parameters on the settlement of peat soil foundation under embankment.The influential factors on the settlement of peat soil foundation under embankment are put forward and the corresponding empirical formula is obtained.