Abstract: The dynamic triaxial test model was established aiming on the longterm dynamic deformation stability problems of the high speed railway subgrade that made of group A, B crushed stone fillers based on the shorttime indoor dynamic triaxial test and the working conditions of the high speed railway subgrade. The dynamic modulus and damping ratio test was conducted for the bed bottom and subgrade body of the group A, B crushed stone fillers. Then, we concluded that the compaction degree, confined pressure are the main influential factors of dynamic modulus and damping ratio. Finally, we established the correlation model of dynamic modulus, damping ratio and dynamic shear strain by considering the influence of compaction degree and the confined pressure. It is confirmed that the dynamic stressstrain relationships can be described using the modified HardinDrnevich model. This is of great significance for the indepth study of longterm dynamic deformation stability of high speed railway.

Key words: subgrade structure, group A, B crushed stone filler, dynamic triaxial test, dynamic constitutive model