, Qujing Urban Expansive Soil Identification And Classification

Expansive soil is a special field in modern engineering geology and soil mechanics, it is a special field kind of clay, different from loess, laterite, soft soil, frozen soil and common clay. Expansive soil is composed of a great deal of strong hydrophilic clay minerals, such as montmorillonite and illite, it has much character, such as expansive construction, many cracks, strong expansive and contraction, intensity decadence. Expansive soil causes people's great attention on figure, specialization of engineering geology character, and it makes great destroy to engineering building.According to the distribution of expansive soil in Qujing urban is very wide, it has typicality, and makes certain endanger, author research judgment and classification of expansive soil in Qujing urban by combine with the project of "Qujing city environment geological survey". This paper is on the basis of researching the cause of formation and distribution of expansive soil in Qujing urban, laboratory experiments have been done on representative samples from Qujing urban, and analyze the experimental data. We use comprehensive discrimination to expansive soil by outdoor geology and physiognomy characteristic, destroy characteristic of building and experimental index. According to the special index and outdoor geology character of expansive soil in Qujing urban , it is divided in strongly, center and the weak expansive soil. It is suggested taking explode-expand stakes to deal with expansive soil foundation by character of expansive soil and the local actual project.