The permeability test of sand with different contents of fines is performed by conventional permeameter

the effect of fines content on permeability coefficient of sand and its correlation with various characterized state parameters are discussed

in which the concept of inter-particle state parameter is employed. It is found that the permeability coefficient of silty sand decreases with the fines content increasing

when the fines content is less than 5%

the effect is very small

while in the range of 5%-10%

the permeability coefficient decreases with increase of fines content sharply

and tends to a relatively stable value under the condition of fines content more than the 25%. Base on the fitting analysis by five types of various characterized state parameters

it is shown that the present common empirical models can not predict the permeability coefficient of sand with different fines content simply and effectively. However the state parameter of void ratio of inter-fines can reflect the effect of fines content on the permeability coefficient of sand better; and its relation of void ratio of inter-fines and permeability coefficient is presented linear correlation in the semi-logarithm coordinates

it is indicated that the void ratio of inter-fines state parameter is suitable for describing the effect of fines content on the permeability coefficient of sand.