Abstract: The laterite soil is widely distributed in Southern Hunan region. The soil has some special properties, such as a high natural water content, large void ratio and strong structural properties, etc., and can be used as special subgrade filling. To obtain the dynamic resilient performance of the soil, the dynamic triaxial tests are carried out to investigate the influence of deviatoric stress, confining stress and volumetric stress on the dynamic resilient modulus. Results show that the dynamic resilient modulus increases with the increase of confining stress and compaction degree and decreases with the increase of deviatoric stress. The dynamic resilient modulus is greatly affected by the water content and reaches a maximum value near the optimum water content. Based on the stress dependence of dynamic resilient modulus revealed with experiments, three typical prediction models for stress dependent dynamic resilient modulus are adopted to perform a regression analysis for experimental data; and then the best prediction model is selected from them. It is found from an error analysis that the prediction model considering confining stress and deviatoric stress provides a higher determination coefficient. That is to say it is the best prediction model of the dynamic resilient modulus for laterite soil in Southern Hunan. The test results and the selected prediction model can provide a basis of experiment and theory for subgrade design of laterite soil in Southern Hunan.

Key words: laterite soil, dynamic resilient modulus, stress-dependence, prediction model, regression analysis