Anyone familiar with prestressed concrete design?

[bonkers325]

I'm taking a prestressed concrete design class and have almost no clue whats going on. Should I kill myself now? Or will ATOT come to my aid? You decide.

 

[Dubb]

uh, how about a specific question so maybe we can help?

prestressed can be stupid easy or quite hard, depening on how mean the prof wants to be.

 

[FoBoT]

are you going to be an architect? civil engineer?

 

[bonkers325]

Originally posted by: Dubb
uh, how about a specific question so maybe we can help?

prestressed can be stupid easy or quite hard, depening on how mean the prof wants to be.

its early-semester stuff... the prof said "this is the fundamental stuff you need to know" except i dont know jack.

part A) I'm trying to find the transfer forces in the pretensioned tendons when Fo=0.75fpu. I have the section properties (assuming a constant flange thickness, not a tapered flange thickness). I'm supposed to find initial prestressing force and the eccentricty for full utilization of ACI Code transfer allowable stresses, assuming straight strands.

part B) Then I am to do the same for strands that are draped 10ft from each side at mid-span.

part C) Then assume the losses make Fe=0.8Fi and solve for Ws for parts A and B.

and then there are a few more parts... i've read the prof's handouts and the book (Prestressed Concrete: A fundamental approach) and i think i've gotten parts A and B correct, but cannot figure out what to do for Part C (I dont even know what Ws is...)

 

[mercanucaribe]

I clicked on the thread thinking it was like those prestressed jeans, and someone pours motor oil and antifreeze on the concrete, cracks it, and makes holes in it, then sells it for twice what it's worth.

 

[hypn0tik]

Civil engineering eh? Fun stuff.