Expansive soil embankment stability and geogrid treatment effect analysis with strength zoning method

n the whole expansive soil embankment,there exist different strength zones due to different water content and dry densitiy caused by the construction course,atmosphere and rainfall.Soil strength in the surface zones usually be strongly attenuated by the alternately wetting and drying,expanding and shrinking.But this condition usually is ignored in the embankment stability analysis.Strength zoning method takes the climate and weather into consideration.Based on the strength zoning method,expansive soil embankment stability and geogrid treatment effect analysis results show that the expansive soil embankment will easily slide in superficial layer if the embankment is constructed by full expansive soils.Stability will increase if the embankment be constructed by lime modified expansive soil,but the emergency capecity is insufficient and the incipient fault is also existence.Superficial stability will increase evidently while the resistance to overturning only increase a little if embankment being treated by geogrid,incipient fault has been effectually reduced or eradicated.All of these show the superiority of the strength zoning method for expansive soil embankment stability analysis.