Simulations of human-induced floor vibrations considering walking overlap

Floor vibration induced by human activities has become an important concern to both designers and developers, especially for modern structures designed with larger spans and lower weights. However, there is currently no systematic approach in codes of practices to assessing floor vibration, and the load models induced by human walking are usually oversimplified by ignoring overlapping between successive footfalls. This paper addresses those shortcomings by conducting a series of finite element simulations of three slabs with different thicknesses subjected to dynamic loads induced by human walking activities. A total of six load models ranging from the most realistic to the most simplified were used for the simulations. The simulation results show that the overlapping time between successive footfalls has a significant impact on human-induced vibration for floors with thicknesses of 100–200 mm. The results also indicate that the critical walking frequency should be shifted to a higher value than the resonant frequency, to allow for the human-induced load increasing with walking frequency.