Many composite beams combine material that has a good tensile strength with material that has a good compression strength (like concrete and rebar).
I was wondering if there has ever been a beam that used tension cables on the side in tension. It seems to me that this might be a cheaper solution than using I beams in certain cases, though it would be more involved construction since cabling pieces would be needed (like turnbuckles).
Could this ever be practical? It seems to me that it could be in very specific circumstances, but I'd like to hear from more knowledgable people because I feel like I'm overlooking something.