Just play a juggernaut. Tanks don't really work in LoL in less they do a ton of damage, which generally gets them nerfed if they do. At least as a juggernaut you can actually damage structures without anyone's help. I think Rammus is the only tank that can actually take turrets (on his own) without building a ton of damage and he's super situational as it is.
Building nothing but defensive items is more or less putting the game into your allies hands. You do no damage, especially not to structures, and you're still going to die fast.