I am modeling a PT floor slab. I am wondering if the prestressing force in the tendon input is considered in RAM as the initial prestressing force or the effective prestressing force after all the losses.
Also, how much percentage loss in prestressing force RAM takes into consideration. Is there a way to look at it in the output so that I can compensate for that force while I apply the force in my input?
This depends on whether you model jacks or not. See: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/2060/ram-concept-tendons-faq Tendon forces shown on screen are final, effective values.
Thanks much, Seth.
I have modeled jacks in all the jacking ends. I have "strands per tendon e.g. 6S" as my input in the tendons instead of prestressing forces. Do I need to increase the number of strands in my input in tendon plans by the percentage of losses to incorporate for the losses i.e. do I need to increase the 6S to 7.5S if the assumed losses are 25%?
This depends on how great the losses and what the desired force is. For illustration, say you have 6 strands and the program calculates a force of 150 kips after losses in one segment (that's 25 kips/strand, it might be more or less in other segments depending on friction, etc). If you were counting on 27 kips per strand, 162 kips for 6, then you would need to go back and increase the number of strands to 7 (or 6.5 if you are OK with fractional strands) to achieve the desired force.