Pretensioned beam design and analysis

SOFiSTiK Teddy
1

Hello
Can anyone point me in the direction of designing a pretensioned beam in SOFiSTiK?

I cannot seem to find any tutorial on pretensioned short beams, with strands that dont have curvature. It all seems focused on prestressed bridge girders with large spans.

2

- you have to define a special prestressing system without friction and slip, tendon area should match the duct area

  • in command CS ICS2 should be zero, this means immediate bond
  • if you wish you can define a force transition length too (see example)
  • in CSM the prestress stage should be before the self-weight activation of the element, this required for the correct stress calculation
  • prestress loss due to elastic shortening of concrete is automatically treated. In the example is directly modeled with a spring. If you deactivate the definition of the group of the spring in CSM you get the same results

precast.dat (1.5 KB)

3

Hello @TomazSabec

Thank you, this is very helpful.

So if tendon area matches the duct area, automatically i have no friction/slip, or should i take any other precautions to make sure this is the case?

4

In tendon definition the friction should be defined as 0.

image

5

Thanks, that helped a lot!