FATEVAS
 

Description:

 FATEVAS is a program for fatigue sizing according to a design code. As an alternative the static sizing according to a design code can be performed. The sizing is based on results from FE analysis of structures, welded or non-welded. The evaluation is done according to the sizing rules of a selected design code. Presently the program can be used with the following design codes: BSK99 (Swedish National Board of Housing, Building and Planning), BS7608 (British Standard, Fatigue design and assessment of steel structures), Eurocode3 (by EU/CEN Comite Europeen de Normalisation) or Plåthandboken (by the Swedish steel company SSAB).

The utilization factor and the fatigue damage ratio are calculated for each load case and for every element (part of a weld or part of non-welded structure) picked, by the user, to be evaluated in the structure under scrutiny. To calculate the fatigue utilization factor and the fatigue damage ratio the following data are considered.

  • Fatigue class (FAT) to apply parallel and normal, Cp and Cv respectively, for the welds
  • Given throat measure, a, for fillet welds
  • Stresses transformed to hold for the local weld geometry
  • The number of load cycles
  • Given ratio for intermittent welds
  • Optionally user defined fatigue resistance Wöhler S-N curve, by default S= FAT class and N = 5×106
The fatigue evaluation can be done on a per load case basis, or for several load cases treated as a sequence in time, thus giving rise to a load spectrum in terms of ranges and mean values :
  • For a load spectrum the accumulated damage is calculated according to the Palmgen-Miner summation rule
  • For a spectrum a utilization factor for stress can optionally be calculated
The ease and flexibility in using FATEVAS rely on the following factors:
  • The choice of design code, the definition of weld layout and fatigue data, etc. is all done as a pure postprocessing task
  • Fast: large structures are analysed in seconds
  • Interfaces with the FE programs: NASTRAN, PERMAS, neutral format
  • Interfaces with the post processors: MEDINA, PATRAN, neutral format
Several alternatives can easily be tried out and the sizing work is very efficient.

 
Ingenjörsdata AB
Box 368
SE - 201 23 Malmö
Telefon Sverige: +46-708 58 92 88
Telefon Kina: +86-152 518 939 38
E-post:stefan.brandt@idab.se
ITECC Idab Technical Engineering Calculation Consultants (Nanjing) Ltd
Room 1134,Building 1
Wanda Plaza Dongfang
No.58,Yunjin Road
Jianye District
Nanjing China