In situ safety barriers
There are a number of different profiles for cast in situ safety barriers, providing varying levels of containment. The choice of profile will depend on the location (e.g. in the median strip or to the side) and the likely traffic on the road. Wider profiles are available that serve the dual purpose of providing vehicle restraint and supporting lighting columns and/or traffic information signs. Concrete barriers are narrower than the conventional post and galvanised steel systems, leading to reduced land requirements. This is particularly important in the median strip between two carriageways where a single, double sided concrete barrier can replace two traditional barriers.
The barriers are constructed using fully automated machines (see Construction/In situ methods/Horizontal slipforming) that can form several hundred metres in a day. Though more expensive initially than conventional systems, they require very little if any maintenance and hence have a low whole life cost. Generally no repair to the barrier will be required after an impact, unlike the traditional ones that will require replacement.