The Elastic Mat and Plate Mat commands can be set to behave as compression only springs and include the influence area that each node has been subjected to in the ANL output file.

In order to allow Elastic Mat and Plate Mat commands to perform as compression only supports to model lift of support situations, the command has been enhanced with an additional parameter which can be set graphically from the command definition.

The Elastic Mat and Plate Mat commands are created from the Foundation sheet in the Supports dialog box.

The Supports dialog can be accessed from the General | Support page in the Modeling mode.

When the Compression Only option is set, then if after any of the cycles of analysis, the force at a node included in the command range (in the elastic mat range or used to define a plate in the plate mat range) is found to be tensile (i.e., negative reaction), then the load case is marked for a re-analysis with that support removed.

There is also a new option to include in the output file, the area that has been used in the calculation of the spring stiffness of each joint used when defining a Plate Mat or Elastic Mat command.