Piping Input menu: Environment > Include Structural Input Files 
Import Model toolbar: Include structural files
Includes an existing structural model into the current piping job. The structural model must have been built and successfully error checked in the Structural Steel Modeler. You can include the names of up to 20 different structural models. The software plots and analyzes included structural models with the piping model.
Piping systems are usually tied to structural steel models by using restraints with connecting nodes. There must not be node number conflicts between structural and piping models. After you define a restraint with a connecting node between the pipe and structure, CAESAR II knows where to place the structure in the resulting preprocessor plot. If no connection between the pipe and the structure is given, the structure is plotted starting from the origin of the piping system. In this case, the resulting plot may not meet your expectations.
Include Structural Files Dialog
File Name
Defines a file to include in the current job. You can type the file name if it is in the same folder as the current piping model file or click Browse to find a file located in any folder.
The software maintains the file location relative to the current job folder. This
is important to remember if you archive or move the current job file.
Add
Adds the file in the File Name field to the list of files to include.
Replace
Replaces the selected file on the list with the file in the File Name field.
Delete
Deletes the selected file from the list.
Browse
Displays a standard Windows Open dialog, where you can select a structural model file to include in the current piping job.
OK
Closes the dialog and process files on the list. The files remain on the list. You can remove the structural files from the current job by removing them from the list.
Cancel
Closes the dialog and cancels all additions and changes made to the list.