Not really - there's one "beach" that I know of:
ANDERSON ROAD CAMPGROUND. But by beach they mean that the rocks are small enough and the shoreline is shallow enough that you can walk into the water.
Long Hunter and Suggs Creek both have swimming areas roped off like a "beach" but I don't know what they're like. I would think there's something up at Nashville Shores too - but I'm not sure how "sandy" any of them might be.
I think there's only one private dock on the whole lake.
That said: you can tie up / anchor off most of the islands and camp. Poole Knobs Island and Rivers Bend Island shallow up enough that you can walk from the boat to the dry shore, but are deep enough that you can not worry about the hull bottoming out at anchor / tied off to a tree or two.