Half of which cars? Half of the posited 10,000 daily? Are you supposing that the bollards are installed in the middle of the carriageway, and painted the same colour as tarmac, and fitted with robotic machine-guns?
Bollards are not like trees. If you hit a tree in a car, the tree will not move. The tree will not fall over. TFA has some pictures of ancient cast-iron bollards, but those are only suitable for use with low-speed traffic in residential neighbourhoods. Modern bollards are made to have some 'give', as evidenced by the number of bollards I see that have indeed been knocked down. I have never seen a tree knocked down as the result of being hit by a motor-car.
Half the cars… that hit the bollards. In my example I said suppose 2 cars per month veer off the road in that stretch.
Of course this is supposition and made-up numbers. And yes I was assuming immovable bollards. If they’re supposed to be there to keep pedestrians from harm, a bollard that lets a car push them 2 feet are an even more pointless waste of money than I was picturing.
Half of which cars? Half of the posited 10,000 daily? Are you supposing that the bollards are installed in the middle of the carriageway, and painted the same colour as tarmac, and fitted with robotic machine-guns?
Bollards are not like trees. If you hit a tree in a car, the tree will not move. The tree will not fall over. TFA has some pictures of ancient cast-iron bollards, but those are only suitable for use with low-speed traffic in residential neighbourhoods. Modern bollards are made to have some 'give', as evidenced by the number of bollards I see that have indeed been knocked down. I have never seen a tree knocked down as the result of being hit by a motor-car.