Maxwell Damping: Systems undergoing dynamic loading, such as an earthquake or explosive blast, naturally dissipate vibrational energy over time. For a dynamic numerical analysis, some form of artificial damping needs to be applied so that the model reproduces such energy losses. FLAC2D includes Maxwell dynamic damping for time-domain seismic deformation analyses. FLAC2D models using Maxwell damping can be much faster, and as accurate, than those models using Rayleigh damping. With Maxwell damping, large, 2D site response and soil-structure interaction can be practical to analyze.
Multi-stepping: When large size or stiffness differences are present in a model, the dynamic multi-stepping option has been much improved. Depending on the model, this can result in much faster dynamic simulations.
Dynamic Input Wizard: This tool pre-processes input signals and outputs a table that can be imported for dynamic analyses. It can do frequency filtering and baseline correction using a variety of methods and export the resulting data.
Ramberg-Osgood Model: Added as one of several hysteretic damping calculations for dynamic modeling. The Ramberg-Osgood hysteretic model overcomes the shortcoming of overly large damping at large shear strains by other available hysteretic damping models in FLAC2D. Hysteretic damping may be preferred where: (1) designers and licensing authorities do not accept fully nonlinear simulations and (2) faster model run times are desired, as additional damping (e.g., Rayleigh) may not be necessary.
Westergaard Approximation: An applied boundary condition for fluid boundaries in a dynamic simulation.