Post Tensioned beam & bonded steel 1

[tw]

Is the bottom bar of the bonded beam steel of post-tensioned beams required to be hooked at column end support? In most PTI details I've seen, they show bottom & top bars to be hooked but I would like to eliminate some congestion.

 

[JAE]

I'm not certain here...so do some research, but I think the bottom steel needs to be detailed in accorcance with the Structural Integrity sections of Chapter 7 of the ACI 318 code. Also, if you use your beams in a lateral resisting frame, you may have conditions with bottom steel in tension at the supports, where you'd need to develop them properly - just like negative top steel would need to be.

 

[blake989]

According to the PCI handbook, there are some alternatives for anchorage at the support. Such as positively attaching(welding) bars to anchorage plates or transverse anchorage bars. The other alternatives shown do not seem to alleviate congestion. The purpose of these details is for end bearing. They outline some potential failure planes that certain amounts of steel should cross. I'm citing a fifth edition PCI. Top steel I'm not sure about, and PCI does not address.