Dead Loading in X-Direction

[Anonymous]

I created a pedestrian truss bridge in Robot with 76 HSS members. Upon analyzing the dead load case, I wanted to check that the summation of the forces in each direction (x,y,z) would be equal to (0,0, *selfweight value*). However, on adding all of the Fx, Fy, and Fz values for the members from Robot, I found that the resulting loads were (8.04kips, -0.1kips, 0.05 kips). This does not make sense, unless the gravity axis is switched such that the x and z axes are reversed. Could you please help? I cannot find a solution to this problem! 

The wind load case has forces predominantly in the z direction too, which is why I think the axes may be reversed somehow, contrary to intuition...

[Rafacascudo · Accepted solution]

You are looking at bar forces tables whick show bar internal forces on local coordinate system.

Instead , check the reactions table , and you will see that everything is correct.