Dynamic analysis of a footbridge subjected to human load

Resumo

The structural branch of engineering is constantly evolving, especially with regard to advances in
modeling with the use of improved software, with trends in optimized processes that aim to save time and money.
Constructive trends have led to the development of more resistant materials and the design of structures capable
of overcoming large spans, using structural elements with smaller sections, that is, thinner, lighter and more
flexible. At the same time, the vibration frequencies of these structures tend to become lower, becoming closer to
the dynamic excitations, subjecting themselves to oscillations that generate some human discomfort or cause a
feeling of insecurity. In this context, the main objective of this research is to verify the performance of a metallic
truss footbridge, subject to human loading and to analyze its natural frequencies and mode shapes. According to
the chosen structure, the dynamic action that will be applied and analyzed in this study was determined. For this,
human excitation was chosen. Newmark's Numerical Integration Method was used to find the system's response
to dynamic excitation. Finally, the developed algorithm was validated and the results analyzed, concluding that
the footbridge under study would meet the acceleration criteria, therefore, requiring no intervention.