THEORETICAL ANALYSIS OF
FATIGUE STRENGTH OF A DOUBLE-DECK BUS BODY USING FEM
Faculty
of Mechanical Engineering, Technical University of Istanbul
Gümüssuyu
80191, Istanbul, Turkey
Modern design techniques primarily consist of finite element analysis of
the vehicle body in a computational media. In this study, an actual double-deck
bus body of domestic production has been modeled in three-dimensions by means of
IDEAS program in order to calculate its fatigue strength. In other words, an
approximation algorithm has been developed to obtain service loads. The effects
of dynamic and static loads on the bus body have been calculated and included to
the FEM analysis. As a new approximation technique, during the service life of a
vehicle under dynamic loads (straight good road, straight bad road, cornering
bad road and singular obstacle road) arising from the road conditions as taking
into account, load spectrum has been constituted. In the design spectrum that
has been utilized in our calculations, considering the equivalence damage effect
rule, instead of using straight good road conditions, other fifty percent of
forces that have been mentioned above, accepted as hundred percent of dynamic
and static forces caused by bad road conditions acting on the bus body. As a
result of this study, the calculated results have been compared to the
theoretical and experimental data taken from literature review. It can be seen
that this approximation technique that we used in our calculations can be used
for this kind of fatigue analysis of vehicle components or bodies.