Angie,
We talked a bit offline, but I'll repeat a few things for the group hoping it sparks some additional discussion.
Foothills has dealt with it a few times on a small scale. The most pronounced one involved post-tensioning in an upper deck overhang. I'd have to go back in our archives to remember the specifics of how we handled it, but you can see in the attached photo the PT heads exposed. I recall that we thought about a few things: (1) level of certainty that the grout installed into the duct was consistent enough to hold the post-tensioning and (2) what would happen if the PT bar released all of its energy at once. Anyway, we could discuss your specific application and see if there are any similarities.
Demo of post-tensioned structures is not very widespread as the technology isn't that old - not too many bridges/bridge components being demoed that have it. I don't think there are too many past projects to draw experience from.
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Reuben Zylstra P.E., M.ASCE
Principal Engineer / Partner
Foothills Bridge Co
Boulder CO
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Original Message:
Sent: 12-07-2023 07:42 AM
From: Angela Hunter
Subject: Pre-stressed and post-tensioned concrete pier demolition
Looking to connect with anyone that has experience in this! If you have any tips, methods, or engineering considerations for demolition of pre-stressed and post-tensioned concrete piers, feel free to post here or we can set up a time to meet and discuss. Thank you!
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Angela Hunter P.E., C.Eng, M.ASCE
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