VIBRATION ANALYSIS OF A STEEL FLOOR SYSTEM WITH DRY FLOORS: A NUMERICAL – EXPERIMENTAL STUDY

Resumo

One of the trends of contemporary architecture is the design of buildings with long spans and
increasingly slender structural elements. In addition, the use of dry floors has been common in
residential and commercial constructions. Thus, the structural design adopted for current buildings is
usually more susceptible to vibrations from human activities, since these structures have lower natural
frequencies. However, researches dealing with the study of vibrations in dry slab floors supported by
rolled or welded steel beams are scarce. For this reason, this project aimed to study the dynamic behavior
of a steel floor system with dry floors. A finite element (FE) numerical model was developed using
ANSYS 19.0 software to simulate this as-built floor system. This numerical model was adjusted and
validated by the first two natural frequencies of the structure obtained by an experimental modal
analysis. In this practical analysis, two accelerometers, an A/D converter and a portable computer were
used to acquire the signals in the time domain. With features and routines developed in MATLAB, these
signals are processed and transformed into the frequency domain by the FFT algorithm (Fast Fourier
Transform). It was observed that the deviation between the numerical and experimental results were
close enough to prove the reliability of the models developed.