Ramp/Bridge Interface in Railway Prestressed Concrete Bridge

The purpose of this paper is to study the factors that contribute to the dynamic behavior of railway ramp/bridge interfaces. A nonlinear, 100‐ton, freight car vehicle model (gross weight 131.5 tons) and a 50‐ft (15.24‐m) long, ballasted prestressed concrete railway bridge were used to determine the approach of the ramp/bridge interface that creates the least dynamic response. The track irregularities on the approach of the ramp/bridge interface and the bridge were generated from power spectral density functions for Federal Railroad Administration (FRA) Class 4 track (maximum speed 60 mph). Impact percentages in the bridge due to a two 100‐ton freight car train operating at 50 mph (80.45 km/h) were calculated. The influences of ramp length and vertical track stiffness in the ramp/bridge interface were studied.