Considering the effect of obstacles and semi-rigid boundary conditions on the dynamic response of the floor under random crowd-structure interaction.

More realistic results of the random crowd-structural interaction dynamic response calculations are crucial for structural vibration analysis and control. And ignoring interactions is considered a conservative approach. This paper analyzes the effect of obstacles and semi-rigid boundary conditions on the random crowd-structure interaction vibration of the floor. The social force model is used to simulate crowd walking randomly in the room, and simulation results are matched with the dynamic calculation of the floor, thus establishing the time-varying dynamic calculation model of crowd-structure interaction. The differential quadrature method and mode analysis method are used to solve the dynamic equations. In addition, the effect of crowd random walking in an environment with obstacles on the time-varying parameters and dynamic response of the floor is discussed. The results show: (a) With the random walking of pedestrians, the floor fundamental frequency first decreases and then increases compared with the no-load, while the change of damping ratio is the opposite. Furthermore, the variation of floor fundamental frequency and damping ratio is greater in the empty classroom (without obstacles) than in the discussion room layout (with obstacles) due to the obstacles. (b) Analyzing the variation of the acceleration response of the floor under the two layouts, it can be found that the installation of obstacles can improve the human-induced vibration of the floor. (c) The vibration problem of the floor can be effectively improved by changing the stiffness ratio in semi-rigid constraint, which provides another idea for the vibration control of the floor. [ABSTRACT FROM AUTHOR]