During the last decades, the need for safer bridges has led to high level aseismatic design of bridges including the use of base isolation bearings. This study numerically evaluates the effectiveness of a promising base isolation bearing, the Friction Pendulum System (FPS), used to improve the seismic performance of highway bridges under strong earthquakes. Nonlinear dynamic analysis and parametric studies are conducted with three-dimensional viaduct models subjected to near-fault earthquakes. The results show that FPS supports can effectively reduce the seismic response at the piers of both straight and curved viaducts. However, curved viaducts subjected to extreme earthquakes may suffer from damage at the expansion joint. In such cases, the seismic performance can be improved by installing unseating prevention cable restrainers as well as changing the bearing arrangement of FPS.