Changes to the lambda model for fatigue loads on steel railway bridges in Europe

article
For the fatigue design of steel railway bridges in Europe, the European standards EN 1991-2 and EN 1993-2 provide a factored Load Model ’71, called the lambda model. The stress range in the fatigue detail of study should be determined with this model. Engineers can easily verify their structural design for fatigue by com paring this stress range to the fatigue reference strength of the detail. This paper compares the load effect caused by the lambda model with the load effect of actual trains measured with ‘Weigh In Motion’ systems during 7 years at 81 lo cations in the rail network of The Netherlands. Locations with heavy loads are se lected and their load effects in terms of stress ranges and fatigue damage are de termined for various influence lines, including one, two and three span beams with spans ranging between 1 and 150 m. The design (i.e. elastic section modulus) is optimized such that the calculated fatigue damage using the damage accumulation rule of Palmgren Miner equals 1 for a 100 years design life for these locations. This elastic section modulus is compared to the elastic section modulus obtained by de signing according to the lambda model.
TNO Identifier
991810
Source
CE/Papers, 6(3/4), pp. 2534-2539.
Pages
2534-2539