Bolt Group Tool Tension Calculation

Question

In RAM Connection Standalone v13 update 3 (13.03.00.33), how is the Bolt Group tool calculating the tension per bolt? It looks like the program is using case I for eccentricity normal to the plane of the faying surface from part 7 of AISC 360, however when I have multiple bolt columns (n), the program is comparing the maximum force from the force diagram (n*rt) with the strength of a single bolt.

Seth Guthrie · Accepted Answer

For out-of-plane analysis we are following the Eccentricity Normal to the Plane of the Faying Surface procedure. AISC360 15th Edition page 7-10. 
 Where we found the equilibrium/neutral axis using a bisection method.

Seth Guthrie · Answer

If you click on the Analysis Method and show the help you will get some details. Copied below: 
 
 Analysis method 
 
 Option that allows to define the analysis method to determine the bolt group capacity when subjected to eccentric loads.

Elastic Method
 The elastic method uses basic mechanics and superposition to estimate the shear stress in each bolt. The load is considered at the center of gravity of the bolt group and a moment added to account for the eccentricity. The stresses for each case are then determined and vectorially added together. 
 
 Instantaneous Center Method
 The instantaneous center method considers that the translational and rotational events occur simultaneously about an instantaneous center of rotation that is located near a line that is perpendicular to the applied force and passes near the original center of gravity of the bolt group. The method also accounts for the ductility of the bolt group and the potential for load redistribution.

Seth Guthrie · Answer

I'll double check with the developers, but this is what the Limcon manual indicated and the Ram Connection methods are similar. 
 Out of Plane Bending 
 Out-of-plane moments on bolt groups are always analyzed using a plastic method in which all tension bolts are assumed to resist the ultimate bolt tension. Using the Ref. 6 method with the neutral axis at the bolt group centroid there can be only one non-zero out-of-plane moment. Behavior is not defined for biaxial out-of-plane bending.