With the track, bridge and its piers taken as an integrated system, the finite element
model to analyze the additional longitudinal forces in continuously welded rails (CWR) on bridges
was established. The distribution of additional longitudinal forces due to temperature and bridge flexure
and the influences of braking forces and the forces due to rail breaking were studied. The results by
simulation conform with the principle of CWR on bridges. A simulation program named BCWR is
presented, which can be applied to the design of CWR on supper-large bridges of high-speed
railways.