Load model 71

from Wikipedia, the free encyclopedia
Load model 71

The load model 71 is next SW / 0 and SW / 2 is the most common load model in the railway sector in Germany and Austria. A uniform load sometimes represents an unrealistic load pattern, but still serves a realistic dimensioning. An example of this is the load model 71 in railways, in which the wheel loads, which represent concentrated loads to a good approximation, are modeled as uniform loads. With this load model, the load envelope of all common loads with the associated wheel spacings is mapped to be on the safe side as a good approximation.

The load model 71 is identical to the load model UIC 71. The local increased loads are represented by the 4 individual loads; for loads over 6 m, the uniform load is a very good approximation, since the exact position of the individual forces is no longer so relevant. The loads are only to be applied if they have an unfavorable effect. When applying the load model 71, one must consider the offset from the plane, which, according to the standard, is composed of the positioning accuracy of the rails, the sinusoidal running of the carriage and the asymmetrical loading.

The load model 71 is deterministic , whereas the Eurocode is based on a semi-probabilistic security concept .

The load model 71 has to be verified with a factor of 1.21 for the verification of the serviceability and the load-bearing capacity in order to show the tendency of heavier trains, however this increase factor is not to be considered for the fatigue verification. (A factor of 1.21 would correspond to an increase of about two notch classes .)

Individual evidence

  1. ^ Lamine Bagayoko: Dynamics of Railway Bridges . In: Solid construction across the board . Springer, Berlin Heidelberg New York 2005, ISBN 3-540-22541-2 , pp. 83-88 , doi : 10.1007 / 3-540-26827-8_11 ( springer.com ).
  2. ^ Payload_ (construction) # Eisenbahnbr.C3.BCcken
  3. ^ H. Freystein: Developments and tendencies in railway bridge construction . In: test engineer . No. 38 , 2011 ( trb.org ).
  4. ^ Francesco Aigner, Helmut Brunner, Herbert Pardatscher: Railway bridges made of heavy steel plates . In: ÖIAZ . tape 145 , no. 3 . Austrian Association of Engineers and Architects, 2000, p. 108-113 ( amazonaws.com [PDF]).