I like you build because no one does it like this...... well except you and me. and MAN IS IT PRO! i would recommend a malady instead of your ionic spark, or maybe both, it is like 500 gold cheaper does similar damage to single targets it works really well with the ult and helps your team tear through champs as you focus them down (if you are running with an ap team mate). all in all i like it though. good job!

He is naturally tanky, with his passive and good beefy stats, as well as having some CC to throw around. He used to be absolutely insane with tank items before the frenzy nerf.
Besides, Everyone EXPECTS tank-bear. This is still good, as well as being tank-y but having much more damage and flexibility, such as the ability to gank, fast jungle clearing(free exp and gold with little time wasted if your just passing through) Significant damage from both types(magic and phys).
All in all I see this as a very versitile build that throws around TONS of damage

just writing for first comment ^^
i don't really understand why u made an AD from him, since he benefits more from tank items, but it's not a bad build.