Need a book? Engineering books recommendations...
Return to index: [Subject] [Thread] [Date] [Author]
POST-TENSIONED: Calculating Friction Losses
[Subject Prev][Subject Next][Thread Prev][Thread Next]- To: seaint(--nospam--at)seaint.org
- Subject: POST-TENSIONED: Calculating Friction Losses
- From: Bill Polhemus <bill(--nospam--at)polhemus.cc>
- Date: Sat, 27 Nov 2004 18:07:52 -0600
I have never had occasion to calculate/estimate prestress losses due to Friction/Wobble/Anchor Seating, all of which are typically concerns for Post-Tensioned Concrete only. The governing equations are defined in ACI 318 Section 18.6.2. However, I'm not absolutely sure I "get" how to apply this. For example, my typical detail for PT slab design shows a tendon trajectory in the slab beams that is an "S-curve" specified to occur for a distance of two times the beam depth. Now, it seems to me that the "alpha" term in ACI 318 Eqs. 18-1 & 18-2 would "always" be Ninety Degrees in such a case. But that's a qualitative assessment on my part, because I'm not sure if I completely understand the definition of "alpha." So, I'm asking for some guidance from anyone out there who does--or has done--post-tensioned concrete design: How have you typically gone about computing the loss due to friction as defined in ACI 318 Sec. 18.6.2? [N.B. Sorry for the rambling missive. I very often find that I can't really phrase my question until I've stumbled around a bit, gathering my thoughts...] Happy Thanksgiving, Everyone. ******* ****** ******* ******** ******* ******* ******* *** * Read list FAQ at: http://www.seaint.org/list_FAQ.asp* * This email was sent to you via Structural Engineers * Association of Southern California (SEAOSC) server. To * subscribe (no fee) or UnSubscribe, please go to:
* * http://www.seaint.org/sealist1.asp ** Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you * send to the list is public domain and may be re-posted * without your permission. Make sure you visit our web * site at: http://www.seaint.org ******* ****** ****** ****** ******* ****** ****** ********
- Follow-Ups:
- Re: POST-TENSIONED: Calculating Friction Losses
- From: Scott Maxwell
- Re: POST-TENSIONED: Calculating Friction Losses
- Prev by Subject: RE: Post v. Column defined
- Next by Subject: Re: POST-TENSIONED: Calculating Friction Losses
- Previous by thread: Re: ON A LIGHTER NOTE
- Next by thread: Re: POST-TENSIONED: Calculating Friction Losses
- About this archive
- Messages sorted by: [Subject][Thread][Author][Date]