The containment capability of post and rail parapets depends, inter alia, on the post spacing. To provide quantitative data on this behaviour, the increased containment obtained by halving the post spacing has been measured in dynamic tests using 5 tonne coaches impacting the parapet at 30 deg. It was found that an aluminium p1 parapet with 3 m post spacing did not contain a coach which struck it with the same severity as the p1 car impact. When the post spacing of the aluminium parapet was halved to 1.5 m it withstood a 2 x p1 impact from a coach, equivalent to the impact of a 20 tonne vehicle at 58 km/h and 15 deg. Halving the post spacing of a steel p1 parapet from 3.66 m to 1.83 m increased its containment capability from 1.6 x p1 impact to 3.2 x p1 impact, a high level of containment equivalent to the impact of a 20 tonne vehicle at 61 km/h and 15 deg. (Author/publisher)
Samenvatting