Shear force diagram with incorrect values

[david.goncalvesR442Q]

I have in my model 2 beams supported by another. Each of the supported beams have approximatly 40 kN of reaction on the principal beam. The Shear force expected on the principal beam was to be about 80 kN, but it is showing less then 1 kN. 

I have modeled just those beams on a new file and the result was correct.

Can anyone tell me what is causing this?

[Rafacascudo]

Could you zip and attach the model?

[david.goncalvesR442Q]

I found the mistake, it was a rigid diaphragm configuration.