What ever speed she was doing, the parapet didn't fail the anchor did, and that's wrong. We design parpaets so the post fail before the anchors and the anchors before the bridge deck edge. You can see that the posts have come way afrom the deck taking coping stones with them, the problem with the detail that was on that bridge is that it's impossible to inspect the parapet anchorages because they're hidden by coping stones. It was an old detail that doesn't meet current standards. The thing is we don't do anything about it unless there's a sufficient risk for the parapet to score highly enough, and that's on trunk roads and motorways, county roads don't have to comply with anywhere near the standards that we have to deal with working on the trunk roads.
There are thousands of bridges with dodgy old details like that on all around the country, there simply aren't the funds to go and find them and fix them, and if we did, it'd be YOU LOT the public that'd be the first to complain because we've got road works on or bridges closed. We now have to jump through huge hoops to put traffic management on trunnk roads during the day, yes that means the bridge inspections that are carried out to pick up defects like this have to be done at night, in the dark, all because the public complain if they're delayed by 10 mins on their journey.
As well as the above it's quite possible to have defects with barriers that you aren't able to discover until they get hit or you come to do works to them. A while ago I found a box beam safety fence protecting a bridge edge that had been anchored into empty ducts within the bridge deck, It looked fine, it was only when we dug some trial holes that we found discovered a problem, it had been like it for over a decade.
The biggest cause of accidents on the roads is the loose nut behind the steering wheel.
