PERMEABILITY AND PARAMETERS OF LANDSLIDE BODIES IN THREE GORGES RESERVOIR AREA

The permeability and permeability coefficient of landslide bodies are great importance to the calculation of the seepage and stability of the reservoir landslides. This paper analyses the test data of 1188 test pits(samples) from 396 landslides in the Three Gorges Reservoir Area. It gets the following conclusions:(1)According to provenance lithology of landslides in Three Gorges Reservoir Area, landslide bodies can be divided into dolomite and limestone, marlite, sand shale interbed. According to the composition structure, landslide bodies can be divided into the homogeneous fine-grained soil, soil containing gravel stone, soil clip gravel stone, crushed rock soil and fractured rock mass. (2)The permeability of landslide bodies is mainly medium and good. Moreover, it has certain regional distribution characteristics. The permeability of landslide bodies in Fengjie, Wuxi and Zhongxian is medium. And the permeability of landslide bodies in other districts is good. The permeability coefficient is positively correlated with the content of gravel stone of landslide body. The permeability of the fractured rock mass is lower than that of the crushed rock soil. (3)The average permeability coefficient of different components of landslide bodies are as follows. The permeability coefficient of homogeneous fine-grained soil is 1.28 m·d^-1. The soil containing gravel stone is 1.41 m·d^-1. The soil clip gravel stone is 2.56 m·d^-1. The crushed rock soil is 3.84 m·d^-1. And the fractured rock mass is 3.24 m·d^-1.