We investigated the effects of a floating floor on heavy impact sound in the low-frequency range below 100 Hz with focus on the structural vibration. To verify the mechanism of amplifying the floor impact sound, field measurements were conducted before and after the installation of a floating floor while the other conditions were kept constant. Field tests were performed on five apartment units where the material properties of the resilient materials in the floating floors differed. Slab accelerations and sound pressure levels were measured simultaneously. The test results indicated that the low-frequency responses of slab acceleration and the corresponding heavy impact sounds were amplified in all apartment units after the installation of the floating floor, while high-frequency responses greater than 100 Hz were significantly reduced. The amplified responses were attributed to the interactions between the mortar plate (floating floor) and concrete slab, which were connected by a resilient material layer. The degree of amplification tended to increase as the loss factor of the resilient material decreased while the amplified frequency range was determined by the stiffness of the resilient material layer. The result was numerically verified using a simplified mass-spring model.

中文翻译：

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浮动地板系统动力特性及其对住宅重物撞击声的影响

我们研究了浮动地板对 100 Hz 以下低频范围内重撞击声的影响，重点是结构振动。为了验证地板撞击声的放大机制，在安装浮动地板之前和之后进行了现场测量，而其他条件保持不变。对五个公寓单元进行了现场测试，其中浮动地板中弹性材料的材料特性不同。同时测量板加速度和声压级。测试结果表明，安装浮动地板后，所有公寓单元的楼板加速度低频响应和相应的重撞击声均得到放大，而大于100 Hz的高频响应则显着降低。放大的响应归因于砂浆板（浮动地板）和混凝土板之间的相互作用，它们通过弹性材料层连接。随着弹性材料的损耗因子降低，放大程度趋于增加，而放大的频率范围由弹性材料层的刚度决定。使用简化的质量弹簧模型对结果进行了数值验证。