Topology optimization of periodic pile barriers and its application in vibration reduction for plane waves

Abstract

Periodic pile barriers, which are used to isolate ambient vibrations from traffic, are traditionally limited by their narrow attenuation zones (AZs) and simple unit structures. Based on an improved genetic algorithm combined with the finite element method, we optimized the topologies of periodic pile barriers to isolate plane waves and maximize the relative widths of AZs (RWAZs). Parameters influencing the RWAZs, i.e., the order of AZs and the elastic modulus and density of soil, were considered. The variation patterns of the optimized structures are presented for both the in-plane and out-of-plane modes. Thus, the influence of the distribution of materials on the RWAZ is revealed and novel unit structures to design periodic pile barriers for mid-frequency vibration isolation are proposed. Both two-dimensional and three-dimensional models were used to validate the screening effectiveness of the optimized pile barriers in the frequency domain.