Living pergola

Has anyone tried a living pergola? We have an uncovered concrete patio on the back of our new house and I'm thinking to enrich the soil along the edge of it and then try espaliered fruit trees all around it with grape vines growing up the trees on one side and across to the other with some strings to train them. Any thoughts? Has anyone tried anything like this? I think if we enrich the soil enough on the side away from the patio that the fruit tree roots would grow that way more so they wouldn't rise up and break the concrete....thanks for any help!

Grape vines would be easy.

Yes, it's mostly the strength and longevity of the trees and how to grow the vines up them in a healthy way thay I'm concerned about...

So, someone has tried this? I am very interested in seeing if this will work. On our small lot this would help me get more bang for my space buck. Plus I think it would be really cool.

I have done this with trees but not with the addition of vines for the "roof".

We have four trees at the corners of our septic tank top which is exposed because of it sitting on bedrock.
The trees have been pruned so that there is an open area under the branches which we can use for shaded seating space or garden container storage space.
The first branches are 7 feet from this concrete surface and the branches now interlace to form a fairly good shade screen.
The tree roots have been pruned so as to not get into the tank surface but rather grow away from it, this was done the first time when the trees were planted.

The one thing that needs to be remembered when root pruning trees, each large root corresponds to a branch, cut off the big root, kill that branch.
I like to get a tree and do some initial root pruning then wait to see which branches have been affected by my pruning, this way I can make a tree map that tells which main root goes to which main branch.

Redhawk

Awesome, that's exactly what we are wanting to do, thanks redhawk!

Apple branches are flexible and the trees can be "pleached" (like espalier, but not planar--often to make tunnels; could be trained in to make a roof but you need at least temporary supports to do so).  Willows (less useful--mainly early pollen for bees, "tea" useful for rooting cuttings of other stuff, and lots of branches for basketry, wattle & daub construction, etc) are traditionally woven into sculptures and rooms.  A small/sparse-leaved vine might be compatible with trees, especially if you don't need full production from them, but in my experience grapes (and most woody lianas, really) are so dang heavy that they will "eat" your fruit trees.  Muscadines grow 20' per year and form thick trunks (4").  Frankly even our arbor failed by becoming a dense thicket.  As far as I am concerned, you don't mimic nature with vines (especially woody ones!)--you regiment them strictly by pruning (on some boring trellis) to keep everything airy and sunny enough, to maximize yields, and to forestall them from world conquest!  Have you considered beans, Apios americana, hops, or maypop (admittedly, these disappear over winter--that's half the point)?  

In the community garden here they have a walkway made out of apple trees. It has a metal structure underneath and it is very pretty.