On the dynamic analysis and design of pultruded GFRP I-beams

Resumo

Pultruded Glass Fiber Reinforced Polymer (pGFRP) members are increasingly used in civil engineering
applications, such as pedestrian bridges and floor systems. Published research indicates gaps in the analysis and
design of pGFRP profiles under dynamic loads. Due to their low modulus of elasticity (about 1/10 that of steel)
and lightweight, dynamic behavior is an essential aspect on the structural response of pGFRP members. This paper
presents results of numerical and analytical investigations on the structural dynamic behavior of pGFRP I-beams
through a parametric analysis that evaluates the influence of the useful height and cross-sections geometry in the
natural frequency variation. Numerical analysis has been carried out in the linear elastic field through Finite
Element Model to determine the modal shapes and related natural frequencies. For this analysis, the structural
elements made of a homogeneous material with elastic properties obtained experimentally are considered. The
results were discussed comparing the analytical predictions provided by different design approaches. Finally, the
analytical dynamic response of pGFRP I-beams was compared with those obtained for steel elements. Performed
investigation shows that pGFRP members are suitable for different human-induced vibrations applications.