MINIMAL CONTACT SURFACE BETWEEN TO BEAMS

Hi

I am a beginner in Karamba and was wondering if maybe anyone could help me??

I am trying to see what is the minimal contact surface in between 2 beams that have the same cross section but are  not aligned.

However, since the central axis of the beams is not continuous, it is a set of lines that are not connected I don't know how to set the lines to convert them into beams.

Or if a should set the upper face of the lower beam as a support to the upper beam?

Here is the file..

Thanks!