Hello, I am new to STAAD and have ran into an issue when checking a model. The model was initially checking for ACI 360-10 so I went to the STAAD Editor and changed the code check command to 2016. This changed the utilization ratio drastically on most of the channels in the design, but it did not effect most of the other sections. In the steel design tab on the critical beam (Beam 20), STAAD shows that the Utilization Ratio went from 0.979 (2010) to 0.65 (2016) changing the critical Code from H1-1b to F2.2.
I am using STAAD CONNECT Edition V22 Update 4
If you have any advice or help that would be greatly appreciated. Thank you!
STAAD HELP.STD
We are investigating some issues with the Cw calculation for channels when designed as per the AISC 360-16 code. Due to a glitch, the software is using a higher value for Cw and that is causing the capacity to be overestimated and the utilization the ratio to go down. We are going to get this addressed in the upcoming release which is coming out in the next couple of months. For now specifically for channels, I would suggest going with the ratio that the AISC 360-10 is reporting.
Thank you Sye, this helps a lot!
The following wiki is now posted with a couple of suggested workaround
https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/50641/staad-pro-is-considering-incorrect-cw-values-in-some-situations-leading-to-incorrect-ltb-capacity-calculations-when-designing-per-aisc-360-16