非洲黑棉土高速路基病害数值仿真及处治对策分析

Analysis on Numerical Simulation and Treatment Strategy of African Black Cotton Soil High-speed Road Subgrade Disease

文章以内罗毕东环路黑棉土地段路基为研究对象,通过建立高速路基病害分析有限元模型,充分分析病害产生的影响因素,并提出了黑棉土路基病害处治对策。研究发现,随着蒸发的持续,路堤土体结构变形逐渐增加,进而引起土体结构内最大主应力随之逐渐增大;随着换填材料渗透系数的减小,最大主应力峰值逐渐增加;当使用弱膨胀土直接填筑时,可使用弱膨胀土填筑下路堤;考虑对中、强膨胀潜势黑棉土进行物理处治,主要进行包边处治和土工膜处治。

This paper takes the subgrade on black cotton soil section of Nairobi East Ring Road as the research object.By establishing thefinite element model for high-speed road subgrade disease analysis,the influencing factors of disease are fully analyzed,and the treatment strategies of black cotton soil subgrade disease are put forward.Research has found that with the continuous evaporation,the deformation of embankment soil structure increases gradually,which leads to the gradual increase of the maximum principal stress in the soil structure;with the decrease of the permeability coefficient of the replacement materials,the peak value of the maximum principal stress gradually increases;when weak expansive soil is used to fill the embankment directly,the weak expansive soil can be used to fill the lower embankment;the physical measures should be considered to treat black cotton soil with medium and strong expansive potential,mainly including hemming treatment and geomembrane treatment.