Beam and Slab Bridge Design
Beam and Slab Bridge Design
(OP)
When I learnt prestressed beam design at college, the section properties (e.g. I value) of the girder don’t change with time or construction stage on which equations or inequalities for the estimations of prestress force and I value are formed.
However, the current problem is a beam and slab that concrete is poured on the top of the prestressed beams to form a “slab”. Thus, the section properties of the structure at “transfer” and “service” are different.
Could any bridge man tell me how I can estimate the required prestress force (and min Z values)????
However, the current problem is a beam and slab that concrete is poured on the top of the prestressed beams to form a “slab”. Thus, the section properties of the structure at “transfer” and “service” are different.
Could any bridge man tell me how I can estimate the required prestress force (and min Z values)????





RE: Beam and Slab Bridge Design
In college the problems are broken into little pieces for simplicity. Now you need to pull them altogether.
If you haven't thrown out your books refer to them for your work. Otherwise invest in a design aid from the post-tension institute or similar organization.
Regards,
![[pipe] pipe](https://www.tipmaster.com/images/pipe.gif)
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RE: Beam and Slab Bridge Design
RE: Beam and Slab Bridge Design
As with going through the design process, think of the problem from the beam side.
i.e. @ transfer, just the beam
@ deck pour, beam supports beam and deck
@ final, composite section carries live load
etc....
Good luck
RE: Beam and Slab Bridge Design
You will find design examples that explain how the superimposed slab interacts with the prestressed beam and how stresses are to be calculated for the intial and final conditions.
RE: Beam and Slab Bridge Design
Nice link
VOD
RE: Beam and Slab Bridge Design