How to account for cable snap (cable loss) in a cable stayed bridge analysis using midas civil?

Creation date: 2/20/2019 1:43 PM    Updated: 4/21/2023 11:41 AM    boundary change assignment cable loss cable snap cable-stayed change general link

The question from the client is

 “Dear support, For cable stay bridges, please add the ability to check cable loss/replacement for multiple cable loss scenarios in one model.”











The client requestioned as:

 “Dear support,

We do not use time history method as we believe this is too complicated and error-prone for this analysis. We use the static analysis method specified in PTI DC45.I where you run the model without the lost/replaced cable to quantify the effects on the rest of the structure. See the PTI extract adjacent to this cell. We have tried to do it using construction staging; a cable can be deactivated to run the analysis, but then you cannot simply reactivate that element, because the locked in forces in the structure will change. So subsequent cables cannot be checked in the same model.”





The here is “Boundary Change Assignment” option in midas civil.




Creating a strong and a weak link between cable and deck




Now, using “Change general link” option in midas civil which change the link property to weak link from strong link.


Then we define the “Boundary Change Assignment” under “Analysis” tab and will assign the “Change general link” property to the Nodal-load load case (CLDF).


Now we can observe in the second picture the additional cable forces due to cable snap.


Thank You!


Files
TH.avi
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