Proposition of a road profile in sine shape to study fatigue life of vehicle suspension components
Luciano de P. Rodrigues1; Rita de Cássia Silva1; Alessandro B. de S. Oliveira1
1 Automotive Engineering, University of Brasília, UnB Gama College
doi:10.20906/CPS/COB-2015-1877
Resumo
It is expected that paved surfaces to develop ruts with time. However even newly paved surfaces can present great roughness caused by inadequate paving process, for example. The interaction between suspension and road generates dynamic forces, which affect both the suspension and the pavement roughness. Vehicles can experience a broad spectrum of vibrations when travelling in roads and, the roughness of a road surface may be described by longitudinal profiles. The international roughness index - IRI represents a numerical scale for pavement roughness. In this work, IRI will be determined to an experimental road profile obtained from the CARSIM® software. An equivalent sinusoidal road profile will be proposed in a manner that its IRI is as near as possible of the experimental road profile. The amplitude and frequency in the sine function is established to provide this equivalence. Then a fatigue analysis is carried out using this sine-shaped profile to determine the SN curve to the control arms of a front Double "A" suspension. Preliminary results indicate that the methodology leads to a good agreement between the SN curves. Sine-shaped road profiles are simpler to reproduce in experimental tests and numerical analyses in order to study fatigue life.
Palavras-chave: Fatigue Analysis; Vehicle Suspension; IRI; Sine-Shaped Road; road profile