Analysis of the Vibration Isolation Performance of Layered Periodic Wave Impeding Blocks in Unsaturated Soil

Abstract

Wave impeding blocks (WIBs) are vibration isolation structures embedded within the foundation to mitigate environmental vibrations and have been increasingly applied in practical engineering in recent years. However, current research on WIBs generally assumes foundations to be single-phase elastic soil or saturated soil. Given the increasing complexity of actual environmental vibrations, traditional homogeneous WIBs struggle to meet the demands of complex vibration isolation. Therefore, this paper introduces the concept of periodicity into the design of WIBs and investigates the vibration isolation performance of layered periodic WIBs in unsaturated soil foundations based on the theory of unsaturated porous media. To accommodate the vibration isolation requirements of source frequencies, the WIB is optimized through orthogonal experiments, and key significant factors affecting the band gap range of the periodic WIB is analyzed. The results indicate that the layered periodic WIB, designed through orthogonal experiments, broadens the frequency range of vibration reduction compared to a homogeneous WIB. The periodic WIB effectively isolates medium and low-frequency vibrations in unsaturated soil foundations under load. The thickness and elastic modulus of the single cell are significant factors affecting the lower bound frequency and upper bound frequency of the layered periodic WIB. Additionally, the vibration isolation effect of the periodic WIB is regulated by embedded depth and saturation degree.