Laboratory Test Study On Strength Evolutionary Rules Of The Evolution Of Lime-fly Ash Aeolian Soil Subgrade Under Complex Stress

With the development of the urbanization, the requirement of construction urban road isrising year by year. New or expanded urban road increased gradually, many technical problemsare encountered in the design and construction of urban roads. Seeking to meet the strength andstability requirements, but also to achieve reasonable economic roadbed filler, it has become animportant issue facing the engineering and technical personnel. The study purpose is improvedthe application effect of flyash improved aeolian soil subgrade to prevent roadbed unevensettlement and other diseases, reduce the project cost and provide references for similar projects.The article is taking the road engineering of sun temple farm logistics park in Bayan Nur asthe project background, the strength evolutionary rules of Aeolian soil and the evolution ofLime-fly ash aeolian soil are researched on theoretical analysis、laboratory experiment and finiteelement numerical calculation. The reinforcement effect is analyzed of the evolution of Lime-flyash aeolian soil.The basic physical and mechanical properties of aeolian soil are researched by laboratoryexperiment and statistical analysis. It shows the aeolian soil has big particles pore and perforedthat fine particles is difficult to adequately fill the pores, it needs improved soil to change theaeolian soil particle size gradation.The strength evolutionary rules of aeolian soil are analyzed by the true triaxial test. Theaeolian soil shear strength showed significant structural, but is still suit for the Mohr-Coulomblaw. The presence of front half portion structural is an important part of its shear strength, itsstructural gradually disappear by the load increasing.The strength evolutionary rules of the evolution of Lime-fly ash aeolian soil are analyzed bythe true triaxial test. The important factors of the shear strength are lime-soil ratio. The lime-soilratio is the overriding factor, such as cohesion and internal friction angle. the compactness of96%and corresponding porosity of11.4%is selected as lime-fly ash subgrade compactionstandard, the mixing ratio of lime incorporation is10%and the fly ash is40%，the best ratio oflime-soil is1:4:5, the optimum moisture content is18%.The stress and displacement fields the road engineering of sun temple farm logistics parkare analyzed by the finite element numerical calculation MIDAS/GTS. It shows that themaximum vertical displacement occurred at the foot of the slope combined the roadbed with old roadbed; The horizontal displacement of the subgrade is suppressed effectively by geotechnicalgrille in the widened roadbed. The scope of the roadbed plastic zone is reduced effectively by theevolution of Lime-fly ash and expected reinforcement effect.