Hi. I create compostie beam. I draw cross-section with stage.
At stage 10. I want the concrete beam have web only.
At stage 20. I want add flange of concrete beam.
I draw Prestress System too
The cross-section axial stress at stage 10 - 19 is correct (The concrete beam have web only)
But when the stage 20 - 30. The cross-section axial stress is incorrect. Like this
Can you help me, what did i do wrong?