Bollards come in different sizes shapes and fixed or just standing there. After the first attack on the World Trade Center, the Port Authority of New York and New Jersey had a challenge for designers the world over on designing effective and good looking bollards. Most of them ended up in a HUD book you can still find on line, and I still use constantly. Bollards are usually based on scientific knowledge, but quite a few are not. Being brought into evaluate bollards has made int apparent that some bollards have no design basis, other than they are heavy. Some where found to be more dangerous than not having them at all. One once hit by a car the size of a VW bug, basically turned into a rolling pin hitting anyone in its way.
from CTI Consulting http://ift.tt/2o7Aeh4