It's too windy to grow runners here, but when we lived in Edinburgh, we built a 'woodhenge' for the beans on our allotment. Three stobs - one at each end of the row and one halfway - smacked well into the ground. Sturdy uprights bolted onto these, and more chunky wood nailed across the top. Then we either used bamboo as climbing poles, attached to the top rail, or string looped under the plants' rootballs (we always have started beans in 4" pots), then tied to the cross beam. The only time they came down was when some 'boisterous youths' ran through the whole place ripping up people's crops, smashing greenhouses, and hauling our stobs right out of the ground. Amazingly, few bean plants were broken and we were able to put the whole thing back up, and we continued to get a crop.
We have found that stinting on the sturdiness of your support structure is false economy. We left the woodhenge in the same place for years and left it for the next tenants too. OK we didn't benefit our other cops with nitrogen from the roots, but we did get reliable bean crops. Now our beans are in the tunnel and we grow them up canes attached to the crop bars.