verification problem 1-009 RE: prestressing, bug?

[jiao]

In this problem, apparently the prestressing force at both ends is not self-equilibrated. There should be some reactions at the supports under this prestressing load case only.
Sap gives 0 reaction.
I think this is a bug.

 

[Diquan]

On both ends is the same force, so ONLY for the prestressing for is equilibrated, when you run the analysis you check the reactions for the prestress and of course is cero!

<Disply> <Show Forces/Stresses> <joints> now select case/combo name: "PRE" --> prestress and that gives cero.

Also open the example with Adobe Reader and you can see that Th=216k on both ends is the same, the location of the tendon is different but it doesn't matter because the force is only horizontal, if it was a fixed end of course is different because it causes moment on the ends, but this is only horizontal force