Assessment of the human comfort of floors based on the use of biodynamic models

Resumo

This research work aims to investigate the structural dynamic response of steel-concrete composite
floors from the point of view of human comfort, when subjected to human walking. This way, the investigated
structural model is related to a steel-concrete composite floor building which is composed of a hot-rolled framing
system, with a total area equal to 1300m2.The floor system is used for normal school occupancy and is supported
by steel-concrete composite columns with a ceiling height of 3.40m. The proposed numerical model, developed
for the steel-concrete composite floor building dynamic analysis, adopted the usual mesh refinement techniques
present in finite element method (FEM) simulations implemented in the ANSYS computational program. In this
numerical model, the steel-concrete composite floor girders were represented by three-dimensional beam elements,
where flexural and torsion effects are considered. On the other hand, the concrete slab was represented by shell
finite elements. Both materials (steel and concrete) have an elastic behavior. The complete interaction between the
concrete slab and steel beams was considered in the analysis, i.e., the numerical model coupled all the nodes
between the beams and slab, to prevent the occurrence of any slip. Regarding the structural behavior of the
connections present in the investigated structural model, the beam-to-beam connections and the beam-to-column
connections were considered as rigid joints. Having in mind to determine if the investigated floor framing system
satisfies the human comfort criterion for walking vibration, the dynamic structural response of the investigated
floor was analysed based on the peak accelerations and RMS values. A numerical study was made of the number
of people influence on the slab using a biodynamic model. Then, the modal and forced vibration analysis numerical
responses were compared to experimental responses. In addition, all numerical and experimental values were
determined and classified according to several human comfort criteria, considering situations of the current design
practice.