I am trying to analyze the steel structure frame which has 4 layers. I am trying to do it in 3D view and having trouble creating layers beneath the layers since the nodes and beams are inter-crossing with each other. I also tried transferring Revit drawing into staad pro but it is creating extra structure members. What is the most efficient way to model the 3D steel frames in staad pro?
I'm not quite sure what you are asking. If you are modeling 4 frames that are parallel and offset then modeling one, then using the copy and paste command with an offset seems best, but there are several ways to accomplish the same thing.
Regarding the Revit - ISM - STAAD.pro workflow, be sure to limit you selection set in Revit to just the primary structural members before exporting to ISM for best results. Some other suggestions related to the node tolerances are here: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/7199/modeling-and-node-generation-best-practices
Its has 4 layers(stories) and 7 bays.Its not parallel since there is arch in the middle span with trusses.
I saw the images you sent me. It's a complicated enough geometry that importing data does seem like a good idea. The images you sent appear like a 3D wire-frame already. Can that be converted into 3D wire-frame .dxf format? If so, that's probably the most expedient way to get the skeleton geometry defined.
See also: communities.bentley.com/.../dxf-drawing-is-not-imported-correctly-into-staad-pro
I have converted to .dxf format from Revit but some of the structure member are missing and also the units are off. When i was starting the new project in STAAD Pro I choose the feet. However, it showing me in inches and in Revit it has been used as feet too.
Thank you
You can change the units int he dxf file itself before importing, or in STAAD you can scale the STAAD.pro model. Here's one way: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/16969/magnifying-or-scaling-down-a-model