I'm currently replacing the Wooden Privacy Fence that surrounds my property. For a span of about 30 feet, my fence runs over a city installed, concrete culvert box. Whoever originally installed the fence simply set shorter wooden posts on top of the cement. I need to know if there is a simple, durable way to support my fenceposts that will be on top of the 3" slab of concrete that is hollow underneath. My best guess is to drill holes through it and install rebar to re-inforce my fence posts and then insert the re-bar into pre-drilled holes in the post. If you have any better ideas, please send them my way.