Well, that was possibly the coolest thing I've watched on YouTube for a while.
How fast was that thing going? It just got pwnd!
And yeah, like Mad says, most bollards are designed to have some 'give' in them to soften the shock of the impact. If that truck were to hit a concrete bollard, tho, the concrete bollard would be knocked sideways and just bend the steel cabling holding it in. Chances are, that thing is solid steel all the way through.
A perfectly circular structure is probably the strongest possible structure. When you consider it's one cylinder of solid steel of about a foot thick, a truck ain't gonna even be noticed. Now, a tank would just bend it, or would simply ride over the top if you angled the treads right. Or, it could miss the bollard entirely and just smash right through the brick wall to the side
But then, who'd use a tank as a carbomb? You'd just fire the cannon.