Gantry beam on laced built up column


I'm designing some built-up columns using equal angle sections and I'm getting some results. Pls can someone check my model if this is correct. I've used the slave-master command to connect the I-beam onto the built-up column. Is this correct as I'm not sure of the results? See below part of my file and some snippets from my CAD model on some of the connections. I look forward to your suggestions. 


Built-Up Columns and Gantry Beam.STD