Optimal design of wave barriers in dry and saturated poroelastic grounds using Covariance Matrix Adaptation Evolution Strategy

In this paper, Covariance Matrix Adaption Evolution Strategy (CMA-ES) is used to optimally design soft and hard wave barriers in half-space soil medium subjected to moving train loadings. Special focus is given to two-phase saturated porous medium of soil and the differences between the barrier characteristics in saturated and dry media are highlighted. Wave propagation caused by moving trains in saturated ground is modeled using Biot’s poroelastodynamic theory and time-domain finite element (FE) numerical simulations. The poroelastodynamic solution is then coupled to CMA-ES as the fitness function of the optimal design procedure. The obtained results show that the optimal barrier characteristics and amplitude reduction spectra (ARS) depend on the ground saturation as well as on the lading frequency and barrier material. It is observed that open trenches, as air-filled barriers, have a very good screening effect in both dry and saturated grounds and their optimal shape has a vertical rectangular configuration. On the other hand, hard barriers such as concrete, have less screening effects and their optimal shape takes slab-like pattern. The effectiveness of double trenches is also explored and it is found that optimal double barriers have better screening effect as compared to that of single barriers.