Study On Failure Mode Of High Fill Slope With Reinforced Soil

This paper studies the Wushan Shennvfeng Airport,according to the survey report about the characteristics of the reinforced soil high fill slope in No.2 ditch of the Wushan Shennvfeng Airport,and the deformation observation data.Through the centrifugal model of reinforced soil fill slope,the deformation and earth pressure variation characteristics of reinforced fill body,grid strain variation characteristics and possible slope failure modes under natural working conditions are analyzed.Using the Cvisc rheological model in the FLAC3 D finite element software,the centrifugal model test of the reinforced slope under variable acceleration loading was numerically simulated,and the slope deformation,earth pressure distribution,and geogrid tensile force distribution after loading were analyzed.characteristics and failure modes of reinforced soil slopes,and the following conclusions are drawn:(1)The maximum displacement of the side slope is mainly concentrated in the range from 1/3 of the slope height to 2/3 of the slope height.When the slope is damaged,local damage occurs first in this range and extends to the inside;will produce a relatively strong deformation.During the loading process of the reinforced soil slope,the deformation of the slope is considered in three parts.From the top of the slope to 1/3 of the slope height from the top of the slope,the deformation is still mainly vertical settlement,with only a small amount of horizontal displacement,the horizontal and vertical displacements of the slope surface are small,and the original slope shape is basically maintained;from the 1/2 slope height from the top of the slope to the bottom of the slope,the slope surface deformation gradually becomes mainly horizontal displacement.Especially in the height of 2/3 of the slope from the top of the slope,there is obvious bulging phenomenon,which can be regarded as a trend or a harbinger of the pull-out failure of the reinforcement.Through the comparison of the three sets of experiments,it can be found that the slope deformation of the steep slope is larger than that of the gentle slope as a whole.(2)The lateral restraint effect of the reinforcement grid can reduce the horizontal displacement of the slope;the reinforcement enhances the overall performance of the soil.The concentration of soil shear stress is reduced,thereby improving the overall stability of the reinforced slope;the reinforcement complicates and Irr egularize s the morphological characteristics of the fracture surface,which is conducive to the exertion of shear resistance.(3)The failure modes of reinforced slope are summarized by analyzing the results of reinforced soil centrifugation experiment and numerical simulation.Including internal damage,that is,the failure surface through the reinforcement of the place;External damage,that is,the failure surface through the rear and below the reinforcement;Compound failure,that is,the failure face passes back through the reinforced soil.(4)The height of the reinforced slope at Wushan Airport is about 50 m,and the length of the reinforcement is 22-30 m.The reinforcement makes the potential rupture surface move backward and form a composite slip surface.The slope stability coefficient is increased from 1.24 to 1.70,and the increase range is the reduction of horizontal displacement is 26%,and the settlement of slope top is reduced by 8%.The effect of reinforcement on improving the overall stability of the slope is obvious.