The ANALYS module computes the linearized SSI problem solution for the required frequency Steps.

ANALYS performs the following computational steps:

  1. Forms the soil flexibility matrix
  2. Computes the soil impedance matrix at interaction nodes.
  3. Determines seismic load vector, including incoherency effects in considered
  4. Solves the equation system for each frequency step and obtains complex response transfer functions for each degree of freedom.

The solution output computed by the ANALYS module contains the complex transfer functions, which, depending on the option required are from the control motion to the final motions or from external loads to total displacements. In either case, the SSI Transfer Function results are stored files that are used by MOTION, RELDISP and STRESS for computing SSI responses.

It should be noted that the ANALYS module can run simultaneously multiple load cases in a single run without need for any restart. For coherent seismic SSI analysis, ANALYS can run simultaneously the all three X, Y and Z direction inputs. For incoherent seismic SSI analysis, ANALYS can run up to 50 simulations is a single run. For vibration analysis or external forces, ANALYS can run simultaneously up to 500 external forcing load cases. The number of simultaneous cases depends only on the SSI model size and RAM available in your workstation.