Prestressed Beam Stresses

Question:

Hi there,

I am carrying out a preliminary analysis of an integral bridge structure, and i would like to check the stresses in the prestressed TY beam.

As we are at preliminary stage I am only carrying out an equilibrium analysis - i have not modelled pile springs, this will be done at detailed design after the beam size and tendon layout has been confirmed. I have however modelled the construction stages.

When checking the results i am not obtaining stresses in the pre stressed beam, during either the construction stage, or post construction.

Having said this, as per the below, there is bending moment diagram is as expected, the PSB is under pure bending (for the pretension load case) and therefore stress.


Can you please advise what the issue is?

Thank you


Answer:

Hello,
Greetings.

Thanks for reaching us.
This is because the beam is composite beam. Beam stresses for composite section are displayed as part wise instead of total.
So, see the stresses as part 1 or part 2 in both construction stage and POST CS as shown below.



Creation date: 6/8/2021 1:56 PM      Updated: 6/8/2021 1:56 PM
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