Numerical Analysis On Stability Of Embankment Over Weak Soil Slope And Anti-slide Shovel Technology

As a cooperative project between China and Algeria,the North-South Expressway in Algeria shuttles through the steep mountains with many sloping embankments.Most of the sloping embankments are located in soft soil such as marl.The southwest of China is mountainous and the northwest of China is mostly on the Loess Plateau.The engineering geology and hydrogeology conditions of the whole western region are not good enough,so it is difficult to avoid the construction of embankments over weak soil slopes for highway construction.In North Africa,such as Algeria,the method of setting anti-slide shovel at the foot of embankment over weak soil slope is widely used.At present,there is a lack of systematic research on how the anti-slide shovel affects the deformation and stability of the embankment over weak soil slope.Therefore,it is of great significance to carry out the analysis of embankment over weak soil slope and the anti-slide shovel technology.Based on the treatment method of Algeria’s North-South Expressway,the embankment over weak soil slope with anti-slide shovel at the foot of the slope is analyzed in this paper.The deformation and stability of embankment model are analyzed by finite element software.The influence under various factors of weak layer on the anti-slide shovel measures is discussed,and the corresponding cooperative measures are put forward.Firstly,the yield process of embankment model under s elf-weight load is analyzed by strength reduction finite element method.The shape and position of circular slip surface are determined according to the dynamic change of plastic strain.The results show that the plastic zone passes through the foot of emb ankment slope without anti-sliding shovel.With the increase of the reduction coefficient,the plastic zone increases gradually and extends upward until the foot of the slope changes obviously.When the anti-slide shovel is installed,the plastic zone moves down to the bottom of the anti-slide shovel.With the increase of reduction coefficient,the plastic zone extends to the outside of the shovel,and the shovel rotates gradually until the plastic zone runs through the top of the weak layer and the shovel rotates obviously.Secondly,the deformation and stability of embankment with or without anti-slide shovel are compared.The influence of the deformation and stability of the embankment over weak soil slope under three characteristics of weak layer is summarized.The results show that the thickness of the weak layer,the elastic modulus of the weak layer and the gradient of the weak layer significantly affect the deformation of the slope embankment,especially the transverse deformation.Therefore,it is particularly important to control the horizontal deformation of the slope embankment.Under the same conditions,the anti-slide shovel can improve the stability factor of the embankment over weak soil slope.Different thickness,modulus of elasticity and slope rate of weak layer will affect the degree of improvement of stability factor.When the slope rate of the weak layer is too large,such as 1:2.5,the anti-slide shovel can not stabilize the foot of the slope.