are they A frames?

I still don't know what to call a unit comprising of 2 playing cards, each supporting the other... but anyway, here is evidence that I undertook the task of building a line of said structures across the stair in the main building at eca. It appears to be easier to do on the stone of the stair rather than the plastic of my studio desk. It fell down a few times but this is the point where I ran out of cards...

It seems that I'm a playing card short of a full deck... no wise cracks thank you.
I'm questioning how interesting this is... Maybe I'll try bringing in loads of playing cards, start at the end of a corridor and see how far I can get? I don't know whether there is a lot to lose in this work. Maybe it's not interesting enough...