Abstract: The effect of the solution concentration on the shrinkage properties of the Kaolin soils are investigated in this paper. The shrinkage limit of a total of six (6) series of samples saturated with NaCl solution of various concentrations were laboratory tested for the shrinkage curves. The salt concentrations in the soil pores would increase with the decrease of the moisture contents. The threedimensional graphs among the moisture content, solution concentration in soil and void ration were plotted by the TableCurve 3D software. A function with three variables were statistically developed through the curve fitting. By using his function, the relationship between the void ratio and the moisture content under different salt concentrations were obtained and the sample shrinkage characteristics are able to be analyzed. The results indicate that, with the increase of the salt concentration in the soil, the shrinkage range increases. The coefficient of the shrinkage, axial, radial and volume strains are also increasing with the increase of the salt concentrations. However, the effect of salt concentration on the Kaolin soil is limited.

Key words: shrinkage tests;NaCl solutions, kaolin soils, shrinkage limit