Connecting two beams that lie on top of each other

Hi all,

I’m trying to model a reciprocal frame in Karamba3D. Therefore, I need to model two beams, where one outer end rests on the middle of the second beam. This can the be connected via a notch or a bolt (as shown in the figure). How can I model such a connection?

image

I cannot model a node in the middle of the lower beam, since it is a continuous beam. If I add a joint in that beam, it splits the beam in two. First, I tried to model a small column between both beams and made it a beam-joint, with the joint in the lower beam having a very high stiffness (as if it is continuous) and the upper joint having a adjusted stiffness, but that doesn’t seem to work for me.

Could someone help me out?

1 Like

Hi, your method would be correct, but you can actually define a joint between those two elements, as well apply a different material to simulate the connection.

Hi Matthew,
Can I ask further on this question of jointing crossing elements? I’m trying to model a varying number vertical columns crossed by a varying number of horizontal rails. I’ve had to shatter the columns once the intersections have been found so that everything can be assembled as a load-sharing system. Are you suggesting that the beam-joint component would find the intersections automatically without intersecting and shattering if applied to the rails ends? I’m anticipating problems defining buckling lengths later down the line with these shattered pieces but I haven’t come to that point yet!

Steve Carney

Hi Steve, the Beam Joint component does not automatically define the joints for you, it only allows you to define any releases at a connection between two different elements - for example if its a pin connection rather than a rigid connection. You can also define a stiffness in the joint too with this component. You will still need to split all the elements to be able to calculate the model.