Warning - This structure is disjointed - Staad Pro Connect

Question

Hello, 
 I am seeking help with connecting my base plates to my structure frame. I receive the warning " Warning - This structure is disjointed " and I believe it is because my plate and structure are not connected properly. How do I do so? I have been having issues with learning the connectivity of members. The file is attached below. 
 Underground Rescue Shelter - Option C R2 - per 1m area supports.STD

Abhisek M · Answer

You can use the multiple structure option as shown in below link to find out where the issue lies. 
 https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/58739/how-to-check-modelling-error-in-structure 
 Here, the model is having 3 independent structures. 
 
 The main reason is the lack of beam plate connectivity. If you have plates, beams/columns and beam ends in a same plane then you should match the beam ends with plate corner nodes. Here, this is not happening. So, you need to establish proper connectivity between beams/columns and plates.