Bridge approach is the controlling section along the highway route, at which the pavement may settle and fracture under the traffic load and environmental factors. Although the concept of embankment stiffness transition has been applied for the structure design at bridge approach, the effects of stiffness transition on the highway structure are still not obvious. Given that, in this paper, FEM simulations were used to systematically investigate the effects of stiffness transition of backfill embankment at bridge approach. The stiffness threshold of embankment at the back of abutment and the ideal transition pattern of embankment stiffness at bridge approach were put forward. The change rule of embankment stiffness for different backfill schemes was analyzed, and simulation results showed that hierarchical optimization was the best way to achieve the uniform transition of stiffness.

CICTP