I ran the study in your files and received an error that the model was unstable. I went through a quick stability diagnosis in a duplicate of your study like this:
1. Go into the study 'Properties'
Turn on 'Use soft springs to stabilize model'
Turn off 'Compute free body forces'
Turn off 'Large displacement mode'
2. Suppress all loads and apply only gravity
3. Mesh/Run the study
4. When the solver stops due to large displacements and prompts to put the study into 'Large Displacement mode' declined this offer. The solver will dump what results it has so far
5. Inspect the displacement plot in the results to find the unrestrained body
The results showed one body was not attached to the rest:
You will want to add an explicit bonded contact set to this solid body to attach it onto the rest of the beam bodies. The Global Contact Bonded definition is, in your case, not able to automatically recognize that you need this. Once you have done that it will probably be stable enough to apply your desired loading onto.
Also, if you want to see other methods for diagnosing unstable studies in Simulation check out this document (GoEngineer - Simulation: Unstable Study Diagnostics) or this video (GoEngineer - Simulation: Common Errors in Simulation).