Numerical modelling of wave barrier in 2D unbounded medium using Explicit/Implicit multi-time step co-simulation

Co-simulation strategies using both Abaqus/Explicit and Abaqus/Implicit are investigated for analysing wave barrier in 2D unbounded soil domain. The Co-simulation is based on the coupling GC method, allowing for coupling different finite element codes with different time integrators and time-scales depending on the partitions of the domain. Absorbing Layers using Increasing Damping (ALID), based on Rayleigh damping, are considered at the boundary to model the semi-infinite medium. The proposed absorbing region is called Hybrid (different time integrators) Asynchronous (different time steps) Absorbing Layers using Increasing Damping (HA-ALID). First, HA-ALID turns out to be more accurate than non- reflective conditions available in Abaqus/Explicit. Second, the time steps for the solid barrier and the HA-ALID are not restrained by the CFL condition imposed by the explicit partition for stability reasons. Third, the critical time step in the domain of interest remains unaffected by the choice of damping characteristics in the HA-ALID, contrary to the case of a full explicit computation. Because of its good accuracy and ability to be realized using only FE Abaqus package, without a third-party software component, this strategy provides a wide range of applications in soil-structure interaction problems.