Utmattning av järnvägsbroar i armerad betong
Enligt eurokoder
Commissioned for this report is Ramboll, Bridge and Tunnel Unit in Stockholm. Theidea throughout the work has been to primarily help bridge designers compilingadvice and instructions on how fatigue verification for railway bridges in reinforcedconcrete shall be performed under the new rules, the Eurocodes.After the introduction of the Eurocodes in 2011 has major problems emerged amongdesigners around Sweden. In some areas, it differs in the calculation rules comparedwith rules from the Swedish Transport Administration and the National Board ofHousing, Building and Planning calculation. Fatigue verification is one area where thenew calculation rules are different from the past.A large part of the report has been to interpret and find the relevant information inthe Eurocodes concerning fatigue. When questions or doubts have surfaced, this hasbeen discussed with Elisabeth Helsing at the Swedish Transport Administration andbridge designers at Ramboll.The result is a report where the structure is organized in the way that the bridgedesigners can move from cover to cover and realize that fatigue verification in realityfollows the same order as the report's sections. The issues have been resolved andreported regularly through the report with complementary findings as a result.Some of the greatest advances in the report are the load combinations to be used forthe method for fatigue verification, how the dynamic factor and the magnificationfactor should be used and how the trainloads to be designed for each method forfatigue verification.