How does the bracing stiffness conversion work for steel composite girder model? Can we directly apply the 0.65 factor to stiffness of the member based on AASHTO code?


Stiffness of section can be updated in stiffness scale factor under properties tabs.


Thanks for the information. But what I want to know is not the input. My question is, 

With the cross frame model in Midas using wizard, how is the "entire" cross frame convert to stiffness? AASHTO is for converting cross frame with a single line of equivalent beam elements, thus, one can use the 0.65 reduction. But in Midas, cross frame is input as truss member and tie to top and bottom of girder, I am wondering on how is this apply?

Midas wizard applies the cross frame as truss member and tie top and bottom member as stated and are designed as truss members. So, complete model for cross beam is used. Model is not using single beam method approach here, thus we need not to update the equivalent stiffness. 
But if the bracing are defined as single beam then, we can update the value of stiffness accordingly as defined earlier.
Creation date: 5/31/2021 5:16 PM      Updated: 9/8/2023 12:34 PM
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