New safety barrier

Press, Volume CXII, Issue 32885, 7 April 1972, Page 6

New safety barrier

Rigid concrete median barriers are likely to become a familiar sight to New Zealand motorists using major urban express routes, says a report in the latest issue of the Road Research Unit’s newsletter. Referring to the danger on busy multi-lane roads of cars crossing into the opposing traffic stream, the newsletter says numerous forms of median barrier have been used throughout the world.

Rigid concrete barriers, in forms developed by General Motors and by the New Jersey state reading authority, are finding increasing popularity because of their effectiveness when there is only a narrow median strip, and because of their freedom from maintenance, the report says. But some of the public show initial resistance to the idea: “. . . possibly based on a natural fear of violent contact with an unbending object.” Such resistance had occurred in New Zealand where the New Jersey type

barrier had been used on the Auckland Southern Motorway and on the Hutt Road. The concrete barriers are designed to guide an out-of-control car into its own lane, while allowing the driver to retain some control and while keeping damage to a minimum as far as possible. On the Hutt Road, steel barriers had been suggested as an alternative to concrete, but concrete was chosen because of cost, maintenance, and the narrowness of the median strip. Overseas reports had shown the success of concrete barriers, the newsletter says. In New York, it had been found steel barriers and chain-link netting both needed considerable maintenance and had repair problems. When the barrier was hit, steel-beam barrier ends tended to spring free and stick out into traffic lanes, and link fencing tended to ball up, and also protrude into traffic lanes. In three years, however, a concrete barrier on a busy section of expressway had needed no replacements. The unique contoured face of the concrete stopped wheels from riding over the barrier, and redirected runaway vehicles into their own traffic lanes. The report also says that by varying the size of concrete barriers they can give some protection from headlight glare, and also serve as a safe platform on which lamp-posts can be mounted.