PSI - Issue 58

Radovan Minich et al. / Procedia Structural Integrity 58 (2024) 80–86 R. Minich et al./ Structural Integrity Procedia 00 (2019) 000–000

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The methodology is very complex. The development of a new bodywork contains both computational and experimental activities: computer-aided design – multibody simulations – FEM calculations – laboratory static and fatigue tests – measurements of vehicle prototypes – fatigue life calculations, see Fig. 1. The methodology is now being further developed at the Regional Technological Institute, the research center of the Faculty of Mechanical Engineering at the University of West Bohemia in Pilsen. A detailed description of the procedure was described by Kepka et al. (2020).

Fig. 1. Schematic representation of the methodology.

Nomenclature S ai

load level of the block (stress spectrum) maximum load level in the block

S a,max

cumulative number of load cycles for load level S ai block size (number of rain-flow cycles) number of cycles to the limit fatigue stage; parameter defining the mean line S-N relationship shape exponent

H i H 0 N f C 0 ν

standard deviation of log N f

S d

number of standard deviations s below the mean S-N curve (S-N line)

inverse slope of the S-N curve (S-N line)

w