Study On The Engineering Geological Features And Precaution Measures Of Landslide On Expansive Soil In AnKang Basin

Expansive soil is a kind of especial clay with high deformability. Absorbing water, it will swell, and when dehumidifying, it will shrink. Many geologic hazards, such as landslide, occur in the expansive soil area. In Ankang basin area, the expansive soil distributes widely and results in enormous economic loss.Based on several geologic engineering surveying reports for expansive soil landslide, abundant soil engineering experiments and correlative datum, by synthesis analysis, this thesis found out the causation that causes the expansive landslide hazards, and obtained the mechanism, features and regularity of them. The conclusions also offer the different engineering constructs corresponding references.There is some particular regularity for the mechanics condition, genetic type, and slide mechanism of the expansive soil landslides in Ankang basin area, as follows:The expansive soil landslides always represent polygenic traction slides. The primary reason is that there is a close inherent relation between the swell-shrinking property and the intension property; The expansive soil landslides also present shallow layer and macrostructure features; The slide bed is grading; The expansive soil landslides take on timeliness and agminate distributing; The expansive soil landslides also have creep deformation features.There are both intrinsic and extrinsic factors for the expansive soil landslide, such as: the genetic type, the soil mass structure and soil texture of the expansive soil slope, the terrain and land features, the effects of ground water and surface water, the weather conditions, and the engineering activities of human.The mechanism of the expansive soil landslide is that in the expansive soil mass, there are varieties of week structural planes that constitute the underlying continuous gliding planes and slide belts. At rainy season, because the precipitation continually infiltrate into the expansive soil mass and hoard up at the gliding planes and slide belts consisted of week structural planes, the water content tends to saturation, witch lead to that the hydrophilic clay minerals absorb water and begin to swell and soften. The coherence and mechanical strength depressed. When affected by the exterior loads and other factors, the expansive soil body produced skid force. Then the landslide comes into being.Only if begin with the geological engineering views and using the synthesis analysis method,...