Mystery Joist/floorboard structure

Was ripping up some board in a new converted loft and spotted this:



Excuse my bad attempt but never had a phone with me to take a pic. Basically under the floorboard is like a V shaped support of some sort which span the length of the room. Not sure why it was there or what it was holding up as I never dug much deeper to find out. All I knew was that it was annoying as it was getting in the way of my new pipe run!

I know its a long shot but does anyone know what this could possibly be?

Cheers

neds - what's it made of, steel or timber?

were they standard joists? It looks a bit like a thing i've seen used in conjunction with I-beams before.

Sorry they were made from timber, I don't think they were or didn't look very joist like. Really baffling!

Cheers!