In order to better imitate the complex dynamic stress field resulting from traffic load, efforts have been made to imitate the vertical and horizontal normal stress coupling in circulation under traffic load. This study is based on triaxial GDS static and dynamic testing system. It is designed to explore the effect of main stress coefficient in circulation and main stress amplitude in circulation on the characteristics of accumulated deformation of saturated clay. And it is expected to create a model to predict the effect of main stress in circulation on the accumulated deformation of saturated clay. The test results reveal that on one hand, the main stress in circulation greatly speeds up the development of permanent principal strain; and on the other hand, with the increasing of main stress coeffi?cient in circulation, the permanent principal strain slows down in accumulating, which shows that main stress in circulation greatly prevents roadbed from sinking under traffic load.