2021 年 42 巻 1 号 p. 22-35
To develop a numerical method of determining the time and frequency characteristics of the external forces excited by various impact sources, the collision between the free-fall mass and the elastic platelike structure are modeled by the one-degree-of-freedom contact model structured on the discrete wave-based numerical analysis of bending vibration with the finite-difference time-domain (FDTD) method. Moreover, the calculated impact sounds were auralized and applied to the evaluation experiment of the subjective impression of loudness and annoyance. As the basic study, the excitation characteristics of generally used devices that is, the impact ball, bang machine, and tapping machine and human trotting are simulated and used for a numerical simulation targeting the prediction of the impact sound pressure levels inside a wall-type concrete structure. After that, the proposed method was applied to a subjective evaluation experiment of the loudness and annoyance influenced by a floor-impact sound on various types of floor slab. The results have shown that the loudness and annoyance induced by the floor-impact sound indicated a high correlation with the maximum A-weighted sound pressure level.