The fatigue airframes were tested to destruction and the Farnborough test rig was demolished. I did read that the foundations are still there. If you can read this thread on Concorde SST the replies are from a former Concorde team member. http://concordesst.yuku.com/reply/42643/static-fatigue-test-airframes#reply-42643
There are a few structural test specimens at the Brooklands Museum.
mmitch.