NONLINEAR

ACS SASSI

The STRESS module computes requested stress, strain, and force time histories and peak values in the structural elements.

In addition to the output file STRESS produces also some specific files useful for postprocessing that contain structural element stress responses in each selected element, respectively, the computed TF (TFU), interpolated TF (TFI) and stress time histories (THS).

STRESS can also generate also compressed binary databases for the computed SSI response element output histories.

STESS may also combine the X, Y and Z input direction element component output histories from the three directional binary databases.

The STRESS module in addition to the above files also generates an important file that contains the maximum element stress components in the center of the elements (calculated by STRESS) for all elements.

If the STRESS post-processing restart option is used, then additional text frame files for postprocessing are generated. These files are used by the ACS SASSI UI module to create structural node stress contour plots, static (for a selected time or for maximum stress values) or animated. The STRESS post-processing handles SOLID and SHELL elements for 3D SSI models. If the SSI model contains both SOLID and SHELL elements, the frames include only average node stresses for the membrane stresses. For the SHELL elements only, separate frames are generated for the average node bending.

If the SSI model includes near-field soil elements that are adjacent to the foundation walls, then the soil pressure frames can be generated. In addition to the seismic soil pressures frames at each time step, a single frame with maximum soil pressures is also generated. The user can also create total soil pressure frames including the static bearing pressures plus the computed seismic pressures. The static pressure file is generated when the soil pressure frames are requested.

For the nonlinear SSI analysis option, STRESS is used together with HOUSE module to carry out the SSI iterations.

The COMB_XYZ_STRAIN module is companion to the STRESS module and combines the directional shear strains using SRSS for the three seismic input directions.

The element output frames at all time steps are also available generated by the STRESS module.