Abstract:To investigate the creep properties of loess in highfill foundation under conditions of high stress and different depth, the CU triaxial creep tests of loess at Yan'an airport are carried out under conditions of different confining pressure. The creep curves of multistep constant load and the equaltime stressstrain curves are obtained by using "Chen method". The results indicate that the creep properties of the loess are obviously influenced by stress level. The stressstrain presents linear properties under conditions of lower stress, and shows nonlinear creep properties under conditions of higher stress. Taking the confining pressure 600 kPa for example, an empirical creep model is proposed in which the stressstrain is described by exponential function and the straintime is described by hyperbolic function. The result shows that the model proposed and the empirical data are high in fitting degree, simple in formality, few in parameters and easy in achievement, can further reflect and predict the creep properties of the loess at Yan'an airport engineering compared with SinghMitchell and Mesri models.