Paper by DARBOIS STOU CHARPENTIER from ISCR 5th 1986 Aachen Germany
Since 1974 some 1000 km of concrete safecy barriers of the New Jersey Cali£ornian type have been built in France, where these structures are known by the designations D.B.A., G.B.A. and L.B.A. These barriers, whether installed on the central reserve or along the outer edges of roads and motorways. are increasingly becoming a seandard feature. They provide extra safety by preventing all kinds of vehicles from leaving the road, so that there are fewer accidents more particularly involving light vehicles colliding with these structures at high speeds and low glancing angles, they make for better traffic flow by reducing the number of accidenes and they are very cose-effective because ehey need no maintenance. Slipforming machines have proved competitive in relation to other existing systems in terms of construction and cost. Some of these machines can achieve rates of progress of 1000 m of barrier constructed per day on some new road-building jobs.