Soil-buried wave barriers for vibration control of structures subjected to vertically incident shear waves

Traditionally, the effects of seismic forces on structures have been mitigated by installing supplemental energy dissipation systems. In this paper, a new approach is explored for the mitigation of earthquake-induced vibrations by obstructing the entrance of seismic energy to the structure through the insertion of some concrete wave barriers within the soil domain. To do so, genetic algorithm (GA) based adaptive optimization methodology is utilized that is capable of finding the efficient layout of the concrete barriers in a manipulated soil zone around the structure. The optimization methodology is coupled with finite element (FE) method for analyzing the complex wave propagation phenomenon in the medium. To investigate the effect of frequency, three single-degree-of-freedom (SDOF) structures with the natural frequencies of 1, 2, and 3 Hz are subjected to the time history ground motions with the predominant frequencies up to 8 Hz. The optimization analyses are performed in the frequency domain, and the efficiency of the obtained solutions is examined by applying time history ground motions in the time domain. The results show that the performance of the buried wave barriers is a complex function of the wave barriers layout, natural frequency of the structure, and the frequency content of the loading. It is observed that some optimal layouts of limited volume can attenuate the elastic demands of the structures to the extent of 30-80%.