PGsplice modeling question

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YL0101
PGsplice modeling question
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Hello, I'm new to PGSplice program and right now working on load rating for a bridge that was built in 1990. This bridge is 3-span bridge, each girder line consists of two prestressed concrete girders that were post-tentioned into continuous span. The abutments and 2 middle piers are skewed at 75 degree. My question is after I modeled the skewed abutment and piers, then ran the load rating, the program just closes automatically. I don't know what wrong with my model, is that because of the skewed angle or anything with my girder modeling? I also attached the PGSplice model for your reference. Thank you.

Attached is the PGsplice model for you to look at.

Rick Brice
PGsplice modeling question

Please post the actual PGSplice input file so we can determine the root cause of the issue

YL0101
Rick, thank you for your

Rick, thank you for your quick response. I modified my post with the actual PGSplice model attached.By the way, I still have some reinforcement to be added in the closure joint (in the design plan, there is no gap between two girders though), but didn't figure out how to do that yet.Thank you.

Rick Brice
PGsplice modeling question

The cause of the problem is the tendon definition. The tendon is longer than the girder.

Point 17 in the tendon profile is at 253.166 ft from the end of the girder, however, the girder is 253.067 ft long. The program is balking at 253.067 ft, so enter 253.066 ft. I'll look into why it isn't accepting 253.067 ft.

I'm not sure how you were able to get invalid input into the program. Perhaps you can share how you built up your model so we can detect this type of issue in the future. My guess is that you moved a pier or changed a pier connection geometry after defining the tendon. That would make the girder shorter and maybe the tendon geometry wasn't updated. Any insight you can provide would be greatly appreciated.

Rick Brice
PGsplice modeling question

An alternative for Point 17 in your tendon profile is to locate it at 100% of the girder length. That way it is always at the exact end of the girder.

YL0101
Thank you Rick! I adjusted

Thank you Rick! I adjusted the girder length to make sure the tendons are within the girders, and I can run the model now. I remember how I got the tendons longer than the girders, at the beginning I set up the girder length and tendons, and there was no skew at abutments and piers. Then later on I input the skew angle at each supports, which somehow resulted in the tendons length longer then the girder.

One more question, I'm not sure how to model the closure joint in the PGSplice. From the design plan there is not gap between the two girders, they were set against each other before post-tension, and a midspan diaphragm was cast afterward. However, seems like the model doesn't let me leave the closure joint at 0 inch, and I also need to input reinforcement at the joint. So could you give me some advice on that? Thank you!

Rick Brice
What you are describing is

What you are describing is basically a match-cast joint. PGSplice does not support such joints at this time. The best you can do is model a small closure joint with material properties that best approximate the real behavior of the structure. Real closure joints are wider than 0", hence the error message. Not sure how you have reinforcement at a joint where the ends of concrete segments are butted up against one another.

Thanks for the information about how the tendon length got messed up. We'll update the software to detect this problem in the future.

YL0101
Hi Rick, do you think I can

Hi Rick, do you think I can model the segment 1 and 2 into one whole segment for each girder line instead of modeling the closure joint? (since I'm not doing design and the final state is what I'm focus on).

Or do you think I can use PGsuper to do the load rating?

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