If you can do it I think it would look good with a simple finger joint between the legs and the uprights.
Ye olde auctioneer(e) decided he was fed up of this particular lot - it was supposed to be a bench, nobody would buy it as a potential bench, so he sold it for sick squid as firewood. While my mum has an excellent wood burner and will happily burn almost anything, this could be more useful to me as, well, a bench.
But, how to do it? The easiest thing seems to be four or six (two on the inside, one on the outside) metal angle brackets, pilot holes, wang in 1 1/2" or 2" no 10 posi heads. Maybe a length of steel bar across the bottom of the uprights?
Quick and somewhat boring? What else can I do? There are tools in the garage, routers chisels etc, but not a lot of wood skill.
Recommend me some ideas, please 2013-06-09 11.24.14_800x600_FIXED.jpg2013-06-09 11.24.03_800x600_FIXED.jpg
15 degree angle on the ends of the short bits, dowel the joint with some 10 or 12mm steel barglue it and use some 8 x 150 SS lag screws to tie it together, heavy sand to clean it up, coat of oil/varnish /stain for looks.
The two pieces of oak that are tucked away under the slabs, look pretty knot free. Assuming that they are aprox 600mm long x 200mm x 150mm and are in sound condition, it could be worth finding someone local to you to rip them down to 600mm x 200mm x 50mm pieces. You then have scope to turn them into more than just a bench.
The second larger piece would be worth just planning and sanding it up a bit, then sell it as reclaimed oak. You might turn it into £50.00 for minimal work, and with that £50.00 you could then look at ex catering stainless benches on Ebay.
edit..sorry I have misunderstood you. I'm now guessing that you meant bench to sit on. I stupidly just thought work bench I'll leave the post as is, but to add that if you want to turn the wood into a bench to sit on, why over complicate it.. Just dig a hole and concrete the two short pieces into the ground, then just rest the other piece on top. I have three in the garden like that, none are screwed together, and none have ever moved off position. Having said about not screwing them down, it is only out of laziness on my part that they have not been done.