This report present a load effect analysis of 35 railway bridges on the iron ore lineMalmbanan. Many of these bridges were originally designed for 25 tonnes axle loador less and is currently the subject of an upgrade to 32.5 tonnes axle load. The mainaim of this study is to explore if the dynamic amplification factor can be decreasedfor the new trains at a speed of 70 km/h.Dynamic effects are often accounted for by a dynamic amplification factor of thestatic response. For real trains EN 1991-2 defines ϕ′ as a dynamic impact componentand ϕ′′ as additional dynamic effects from track irregularities.