Equivalent force in a cross-section

[jfymsam86]

Hi
I applied a cyclic displacement to tip of beam. Now I’m going to find the equivalent Force at this section. By RF, I can find each node force. But for total Force, if I calculate the summation Force of all nodes, regarding to cyclic loading (displacement) and compress and tension in the cross section, the loads are negative and positive, and they almost will neuter each other.

So can I use coupling or tie for 1 node of cross-section before analyze?
Continuum or kinematic?
What about tie?

or summation is true??????

Thanks beforehand.