Abstract This paper presents a new geosynthetics isolator composed of stacked sandbags for buildings’ base-isolation method to improve human comfort under subway-induced environmental vibrations. The static and dynamic mechanical properties of the isolator are tested in a laboratory first. Then field experiments are performed with a full-scale building to investigate the effectiveness of the isolator. The results indicated that the bearing capacity is mainly influenced by the soft contact interfaces between different sandbags, and is sufficient for most low-rise and mid-rise buildings. Similar to some springs in a series, the soft contact interfaces make the vertical stiffness of the isolator low enough to isolate vibrations. The friction forces between sand particles are a benefit to dissipating energy, which increases the damping ratio to 14%. After the installation of geosynthetics isolators, the vertical vibration and secondary air-borne noise inside the building are effectively suppressed, and therefore the comfort for residents is enhanced. Further, there is no negative impact caused by automobile vibrations on the isolated building because the damping ratio of the isolator is high enough to resist resonant amplitudes. These results demonstrate that the isolator is feasible for buildings near subway transportation.

中文翻译：

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地铁竖向振动及二次空气传播噪声建筑物沙袋隔振器试验研究

摘要 本文提出了一种新型土工合成材料隔振器，由叠层沙袋组成，用于建筑物基础隔振方法，以提高地铁引起的环境振动下的人体舒适度。首先在实验室测试隔离器的静态和动态机械性能。然后在全尺寸建筑物上进行现场实验，以研究隔离器的有效性。结果表明，承载力主要受不同沙袋间软接触界面的影响，对于大多数中低层建筑来说已经足够了。与系列中的一些弹簧类似，软接触界面使隔离器的垂直刚度足够低以隔离振动。沙粒之间的摩擦力有利于耗散能量，使阻尼比增加到 14%。安装土工合成材料隔振器后，有效抑制了建筑物内部的垂直振动和二次空气传播噪声，提高了住户的舒适度。此外，由于隔离器的阻尼比足够高以抵抗共振振幅，因此不会因汽车振动对隔离建筑物造成负面影响。这些结果表明隔离器对于靠近地铁交通的建筑物是可行的。由于隔离器的阻尼比足够高，可以抵抗共振振幅，因此不会因汽车振动对隔离建筑物造成负面影响。这些结果表明隔离器对于靠近地铁交通的建筑物是可行的。由于隔离器的阻尼比足够高，可以抵抗共振振幅，因此不会因汽车振动对隔离建筑物造成负面影响。这些结果表明隔离器对于靠近地铁交通的建筑物是可行的。