Car Park Collapses in Ontario

In the UK we have issues with long term car park structural integrity. The number of collapses is small and so far no one has died but last winter several large structures were closed when structural weaknesses were identified which pointed to an imminent failure. Therefore I look on stories about car park structural failures with great interest. Sadly a young man died in Milwaukee in late June when a facing panel fell off a car park there. The main structure of the car park did not seem to be affected but initial reports suggest that the panel's fixings may be suspect. We had some issues with perimeter barrier safety in the UK and changed the rules. Some of the edge treatments that I have seen in the USA are frankly scary, but different strokes...

In Ontario a more spectacular failure occurred when the top deck of an underground parking structure collapsed, slightly injuring one man. It seems that the man, a painter, was working on the car park's ground level top deck and the collapse occurred when he drove a self powered "cherry picker" across the deck.

There are a number of issues with this failure. The top deck had had a layer of asphalt applied which could have overloaded the structure according to an engineer involved in the aftermath. However, the according to the same source the "cherry picker" weighed 10,000 kilograms which is nearly five times the weight of a Hummer and which might have had more than a little to do with the failure. Further one commentator has already questioned the design of the column/slab connection suggesting that this could be an inherent design weakness. I don't know but seems to me that we have an imperfectly understood structure which has been used, or abused beyond its capabilities with the inevitable result.

Perhaps it's past time when the business of designing and taking care of a car park structure requires a specialist and is too complex for generalists to deal with?