/diy/ - Do It Yourself

I have two pieces like in the picture.

And the bottom i need to connect the two piece to form a solid static joint. (so the result will be as if they were glued together)

Is this possible without glue? Is there some simple joint i can model to achieve this?

I can (doesn't have to be) even be only one way joint, where you can join them together but not take them apart-
You know, something where i just click them together like lego