Vibration Reduction Of Rayleigh Waves By Periodic Wave Barriers In Layered Single-phase Soil

Different from natural disasters such as earthquakes that bring accidental and direct damage to buildings and people’s life and property,environmental vibration brings less harm to people’s lives and livelihoods than ground shaking,but its effects are often longlasting and continuous,so how to isolate environmental vibration has become a hot research problem.Compared with body waves,because surface waves carry a lot of energy and decay is slower than body waves,the current research on how to effectively isolate surface waves has become a hot topic in environmental vibration reduction.Second,there are still some limitations on how to open the attenuation domain of surface waves in the low frequency bands.Therefore,this paper will study the vibration damping characteristics of periodic wave barrier to Rayleigh wave in layered single-phase soil,and identify the surface wave with the help of energy distribution parameter criterion,the main contents are as follows:(1)Based on the periodic structure theory,with the help of the PDE module in the finite element analysis software COMSOL,the complex frequency scattering analysis of the periodically filled trench,periodic wrapped pile and combined periodic wave barrier in the layered single-phase soil was carried out,and the attenuation domain of Rayleigh wave was calculated respectively.(2)On the basis of obtaining the complex frequency dispersion curve,the influence of the viscosity of rubber materials in the cyclic filling trench and the periodic wrapped pile barrier on the vibration damping characteristics of Rayleigh wave was analyzed.(3)The influence of the density and elastic modulus of the primary soil and the elastic modulus and density of rubber materials on the Rayleigh wave attenuation domain was studied from the perspective of physical parameters.From the perspective of geometric parameters,the effects of rubber layer thickness and periodic barrier spacing on the Rayleigh wave attenuation domain are considered.(4)The numerical analysis models of layered single-phase soil-periodic filling trench,layered single-phase soil-periodic wrapped pile and layered single-phase soilcombined periodic barrier were established,and the vibration damping characteristics of the wave barrier were analyzed from the perspectives of frequency domain and time domain.The results of this paper show that the use of the periodic filling trench and wrapped pile barriers composed of two materials,concrete and rubber,in layered single-phase soils can open a wider band gap and thus can effectively attenuate low-frequency Rayleigh waves;the viscosity of the rubber material has an attenuating effect mainly on Rayleigh waves outside the attenuation domain;the attenuation domain of the combined periodic wave barriers contains both part of the vibration isolation bands of the above two types of periodic barriers and the vibration isolation bands they do not cover,and can open a band gap at lower frequencies,with good vibration isolation effects.